Refrigeration system with pressure exchanger and controllable elements

Abstract

The system comprises a pressure exchanger (PX) configured to receive a first fluid, receive a second fluid, and exchange pressure between the first and second fluids. The system further comprises a heat exchanger configured to receive the second fluid from the PX via a first inlet, receive a third fluid via a second inlet, and exchange heat between the second and third fluids. The system further comprises a first compressor configured to receive the third fluid from the first heat exchanger.

Description

[[Technical Field]]

[0001] The present disclosure relates to system control, and more particularly to control of refrigeration and heat pump systems including a pressure exchanger. [[Background Art]]

[0002] Systems use fluids at different pressures. Systems use pumps and / or compressors to increase the pressure of the fluid. Much of the energy usage of a fluid treatment system can be consumed by the pumps and / or compressors that increase the fluid pressure.

[0003] The present disclosure is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings. [[Brief Description of the Drawings]]

[0004] [Figure 1A] FIG. 1A is a schematic diagram of a fluid treatment system including a hydraulic energy transfer system according to some embodiments. [Figure 1B] FIG. 1B is a schematic diagram of a fluid treatment system including a hydraulic energy transfer system according to some embodiments. [Figure 2A] FIG. 2A is an exploded perspective view of a pressure exchanger (PX) according to some embodiments. [Figure 2B] FIG. 2B is an exploded perspective view of a pressure exchanger (PX) according to some embodiments. [Figure 2C] FIG. 2C is an exploded perspective view of a pressure exchanger (PX) according to some embodiments. [Figure 2D] FIG. 2D is an exploded perspective view of a pressure exchanger (PX) according to some embodiments. [Figure 2E] FIG. 2E is an exploded perspective view of a pressure exchanger (PX) according to some embodiments. [Figure 3A] FIG. 3A is a schematic diagram of a fluid treatment system including a PX and a heat exchanger for exchanging heat between flows of working fluid according to some embodiments. [Figure 3B] Figure 3B is a schematic diagram of a fluid processing system including a pressure exchanger and a low-pressure valve according to several embodiments. [Figure 3C] Figure 3C is a schematic diagram of a fluid processing system including a supercooler and a superheater according to several embodiments. [Figure 4A] Figure 4A is a schematic diagram of a fluid processing system, according to several embodiments, which includes a PX, an auxiliary gas cooler, and various controllers and other components for providing control of the fluid processing system. [Figure 4B] Figure 4B is a schematic diagram of a fluid processing system including sensors and a controller according to several embodiments. [Figure 5A] Figure 5A is a flowchart of a method for providing control of a fluid processing system according to several embodiments. [Figure 5B] Figure 5B is a flowchart of a method for providing control of a refrigeration system according to several embodiments. [Figure 6] Figure 6 is a block diagram showing a computer system according to a specific embodiment. [Modes for carrying out the invention]

[0005] Embodiments described herein relate to architectures of refrigeration and / or heat pump systems including pressure exchangers, and control of such systems. For example, architectures may include refrigeration systems, heat pump systems, pressure exchanger systems, fluid handling systems including pressure exchangers, heat transfer systems, control systems for carbon dioxide (CO2) refrigeration systems integrated with rotary pressure exchangers, and control units for such systems. In particular, system architectures and associated control modules for controlling, maintaining, regulating, etc., the operation of a system including one or more pressure exchangers will be described.

[0006] A system may use fluids at different pressures. One fluid supply to the system may be at a lower pressure, while one or more parts of the system operate at higher pressures. A system may include a closed loop where different fluid pressures are maintained in different parts of the loop. These systems may include refrigeration systems, heat pump systems, energy generation systems, fluid transport systems, and so on. Pumps or compressors may be used to increase the fluid pressure in such systems.

[0007] Conventionally, heat transfer systems (e.g., refrigeration systems, heat pump systems, reversible heat pump systems, or similar) use pumps or compressors to increase the pressure of a fluid (e.g., refrigeration fluids such as carbon dioxide (CO2), R-744, R-134a, hydrocarbons, hydrofluorocarbons (HFCs), hydrochlorofluorocarbons (HCFCs), ammonia (NH3), refrigerant mixtures, R-407A, R-404A, etc.). Conventionally, a separate pump or compressor mechanically coupled to a motor is used to increase the fluid pressure in any part of the system, including increasing the fluid pressure. Pumps and compressors, especially those operating with large pressure differences (e.g., those causing a large pressure increase in the fluid), require a great deal of energy. Therefore, conventional systems expend a great deal of energy increasing the fluid pressure (via pumps or compressors driven by motors). In addition, conventional heat transfer systems reduce the fluid pressure through expansion valves and / or heat exchangers (e.g., condensers and / or evaporators, etc.). Conventional systems inefficiently increase and decrease fluid pressure. This is wasteful in terms of the energy used to operate conventional systems (for example, the energy used to repeatedly increase the pressure of a refrigerating fluid to cause an increase or decrease in ambient temperature).

[0008] The systems, apparatus, and methods of this disclosure enable the operation and control of a system (e.g., a fluid processing system, a heat transfer system, a refrigeration system, a heat pump system, a cooling system, a heating system, etc.) that includes one or more pressure exchangers (PXs). In the system, the PX may be configured to exchange pressure between a first fluid (e.g., a high-pressure portion of a refrigeration fluid or working fluid in a refrigeration cycle) and a second fluid (e.g., a low-pressure portion of a refrigeration fluid in a refrigeration cycle). The PX may receive the first fluid (e.g., a high-pressure portion of the refrigeration fluid) through a first inlet (e.g., a high-pressure inlet) and receive the second fluid (e.g., a low-pressure portion of the refrigeration fluid) through a second inlet (e.g., a low-pressure inlet). When entering the PX, the first fluid may be at a higher pressure than the second fluid. The PX may exchange pressure between the first fluid and the second fluid. The first fluid may exit the PX through a first outlet (e.g., a low-pressure outlet), and the second fluid may exit the PX through a second outlet (e.g., a high-pressure outlet). When the second fluid flows out of the PX, it may be at a higher pressure than the first fluid (for example, pressure may have been exchanged between the first and second fluids).

[0009] In some systems, fluids may be pumped, compressed, have their pressure increased, or similarly, in various parts of the fluid processing system. For example, a main compressor (or set of compressors) may work to increase the pressure of a low-pressure fluid to a high-pressure fluid, and other compressors or boosters may be used to provide auxiliary pressure regulation in other parts of the fluid processing system. In some embodiments, one or more adjustments to the fluid flow path may be introduced to reduce the number of pumps or compressors required, for example, by using a PX to perform compression that was conventionally performed by a booster pump. Furthermore, a PX may be used to reduce the pressure of the working fluid in various parts of the fluid processing system, for example, by replacing one or more expansion valves while using the lost pressure to pressurize other fluid flows.

[0010] In some embodiments, a heat transfer system (e.g., a refrigeration system, a heat pump system, etc.) may target controlled operating conditions. For example, a refrigeration system may target a specific temperature in a refrigerated zone (e.g., for the safe storage of perishable goods such as food, pharmaceuticals, or materials for scientific or research purposes), a heat pump system may target a comfortable indoor temperature in a home, a system may target the rate of heat exchange between the system and the environment, and one or more parts of the system may target operating temperature, pressure, fluid density, or similar parameters. The operating parameters for maintaining the target conditions may depend on many factors, such as ambient temperature, the mass, type, and initial temperature of the material in the temperature-controlled area, and the frequency of material and / or energy exchange between the control area and the surrounding environment.

[0011] In some embodiments, the PX may be operable within a range of operating speeds. For example, a rotary PX may be operable at various rotational speeds, and a reciprocating PX may be operable at various cycle frequencies, etc. The PX may be coupled to a motor. The motor may be configured to control the operating speed of the PX. The operating speed of the PX may affect the fluid flow rate, fluid pressure, etc., in various parts of the fluid processing system. In some embodiments, the motor may drive the PX. For example, if the goal is to increase the flow rate through the PX, the motor may increase the operating speed of the PX. In some embodiments, the motor may play a role in suppressing the PX. For example, if the goal is to decrease the flow rate through the PX, the motor may suppress the motion of the PX to maintain the desired flow rate. A controller may be operationally coupled to the motor of the PX. The controller may receive data collected from one or more parts of the fluid processing system, such as pressure data indicating the fluid pressure associated with (e.g., inside and out of) a condenser in the fluid processing system, flow rate data indicating the flow rate through a part of the fluid processing system, or similar data. The controller may generate a control signal for the motor based on received data indicating one or more operating conditions of the fluid processing system. The motor may be configured to adjust the operating speed of the PX based on that control signal.

[0012] In some embodiments, the operating speed of the PX may be used to maintain one or more conditions of the fluid system. For example, the PX speed may be selected to maintain a target fluid pressure in components upstream of the PX. The PX speed may further affect other conditions of the system, but the influence of the PX speed on multiple conditions and components of the system may make it at least partially uncontrollable. Additional control methods may be used to maintain one or more target conditions of the fluid system that may be further affected by the operating speed of the PX.

[0013] In some embodiments, the fluid system may include one or more control valves that can be opened or closed to enable a target fluid flow rate, a target upstream fluid pressure, a target downstream fluid pressure, or the like. The control valves may be coupled to the high-pressure outlet of the PX and included in the fluid system. For example, fluid may flow out of the high-pressure outlet of the PX, pass through an auxiliary gas cooler, and be supplied to the control valve. The control valves may have an adjustable opening that is adjusted based on one or more inputs to maintain target conditions of the fluid system. The opening of the control valves may be adjusted to maintain a target travel distance of the PX.

[0014] The travel distance is a measure of the inflow or outflow of fluid into or out of the duct of the PX. For example, fluid may flow into the duct from a first inlet and exchange pressure with a second fluid that flows into the duct from an inlet located on the opposite side of the duct. The fluid can then be removed through an outlet located on the same side from which it entered after the pressure exchange. The travel distance is a measure of how far the first fluid flows into the duct before receding and returning to the outlet. The travel distance indicates the volumetric flow rate through the PX and is based, for example, on the rotational speed of the PX, the number of ducts in the PX, and the total volume of the ducts in the PX. The two inlets of the PX may each have an associated travel distance. For example, during operation, the PX may operate with a first low-pressure travel distance associated with the movement of fluid supplied to the low-pressure inlet of the PX and a second high-pressure travel distance associated with the movement of fluid supplied to the high-pressure inlet of the PX. The target travel distance may be selected based on the target volumetric flow rate through PX, target energy efficiency, target pressure exchange efficiency, target mixing ratio of the first and second fluids, or similar factors.

[0015] The travel distance of one or more PXs can be adjusted and / or maintained by adjusting the operation of components of the fluid transmission system, including the PX. For example, the low-pressure inlet travel distance (e.g., the volume of fluid supplied to the low-pressure inlet of the PX relative to the working volume of the PX) can be maintained by adjusting the opening of a control valve coupled to the high-pressure outlet of the PX. The working volume of the PX depends on the operating speed of the PX. For example, in a rotary PX, as the rotational speed increases, the number of PX ducts utilized within a given time increases. The control valve may be configured to be controlled based on the PX speed to maintain a target low-pressure inlet travel distance within the PX. Furthermore, when setting the opening of the control valve, additional signals such as the overall system load (e.g., the total fluid flow rate through the system), the temperature in one or more gas coolers, and the temperature of the fluid in one or more parts of the fluid handling system may be considered.

[0016] In some embodiments, the fluid system may include one or more heat exchangers, for example, to exchange heat between fluids at different locations in the fluid treatment system. For example, the fluid treatment system may include a heat exchanger for cooling the main fluid flow from the main gas cooler. A portion of the fluid provided by the gas cooler may be supplied to a cooling fluid channel of the heat exchanger to cool a main portion of the fluid. The proportion of fluid supplied to each fluid channel may be determined by a control valve. A target cooling condition is monitored, and the proportion of fluid supplied to a primary channel or a secondary channel of the heat exchanger may be adjusted to achieve the target cooling condition, for example, to achieve a target supercooling degree of the main fluid supplied to the heat exchanger. In another example, the fluid treatment system may include a heat exchanger for exchanging heat between high-pressure fluid flowing out from a high-pressure outlet of a PX and another fluid, such as a fluid supplied to one or more compressors of the fluid treatment system. Such a configuration may increase the proportion of liquid in a receiver coupled to the high-pressure outlet of the PX (for example, it may reduce the pumping requirement for compressing flash gas and improve the efficiency of the system), and may increase the temperature of the fluid supplied to one or more compressors (for example, for a compressor that may be damaged if liquid is supplied to the compressor suction portion, it may protect the compressor from damage). Such a heat exchanger may provide superheating (for example, additional heat exceeding the heat required for vaporization) for the fluid supplied to one or more compressors.

[0017] In some embodiments, the superheating heat exchanger may obtain fluid from the high-pressure outlet of the PX, and exchange heat in the fluid with the fluid supplied to the compressor of the system. In a first example, the superheater may be coupled to the fluid supplied to an inlet of a main compressor, for example, all working fluid supplied to the main compressor may be heated by the superheater. In some embodiments, only a certain combination of flow paths may pass through the superheater, for example, any combination of outputs from one or more evaporators including flash gas, medium-temperature evaporators and low-temperature evaporators (before or after any additional compressors) may pass through the superheater.

[0018] In some embodiments, the fluid processing system may include a control valve associated with a fluid flow path from the high-pressure outlet of the PX to the receiver. This flow path may include one or more components for lowering the temperature of the fluid, such as an auxiliary gas cooler, a heat exchanger (e.g., the superheated heat exchanger described above), or similar. A control valve associated with an auxiliary gas cooler may be opened to determine the amount of fluid passing through the auxiliary gas cooler, for example, to determine the distance traveled by the PX. A control valve associated with this flow path may be opened by an amount based on the opening of other valves in the flow path, and may be a control valve configured to determine, for example, the proportion of fluid supplied to the secondary channels of the heat exchanger in the fluid processing system. A control valve associated with this flow path may be opened to allow a flow rate through the control valve that matches the flow rate through other valves controlled based on other criteria of the fluid processing system. A control valve associated with this flow path may be operated based on an indication of the mass flow rate of the fluid, which may include a measured flow rate, a flow rate derived from the fluid characteristics and the operating speed of one or more components (e.g., a low-pressure booster associated with a low-pressure inlet, the operating speed of the PX, etc.), and flow rate equivalence based on the characteristics of the fluid at various locations in the fluid processing system.

[0019] In some embodiments, the fluid treatment system may include a mechanism for adjusting heat transfer efficiency of one or more heat exchangers, condensers, gas coolers, etc. For example, an auxiliary gas cooler may comprise or be associated with one or more fans for increasing heat transfer from the gas cooler to the vicinity thereof (e.g., the surrounding environment). Activation and / or operation of a device for adjusting heat transfer efficiency (e.g., adjusting the fan speed of an auxiliary gas cooler) may be based on the temperature of fluid discharged by the gas cooler. In some embodiments, operations may be performed to achieve and / or maintain a target temperature of the fluid discharged by the auxiliary gas cooler. The target temperature may be based on the ambient temperature; for example, the target temperature of the fluid after passing through the gas cooler may be within a target temperature range of the ambient temperature, for example, within 5 degrees Celsius of the ambient temperature. The target temperature may be based on the temperature of fluid at other locations in the fluid treatment system, for example, the temperature of fluid discharged by the main gas cooler. Additional architectures, sensors, processing devices, etc. may be used to maintain the target or optimal conditions of the fluid discharged by the main gas cooler, and fewer sensors or other architectures may be used to match the fluid discharged by the auxiliary gas cooler to the fluid discharged by the main gas cooler.

[0020] In some embodiments, the control of the proportion of fluid supplied to the primary and secondary channels of the heat exchanger may be based on the conditions of the receiver, either alternatively or additionally to other conditions. For example, the subcooling supplied to the main fluid flow in the heat exchanger may reduce the amount of flash gas accumulating in the receiver, for example, by lowering the temperature of the fluid supplied to the receiver. In some embodiments, a flash gas valve may be used to allow flash gas from the receiver to be directed to other components of the fluid processing system, such as a main compressor. The degree of subcooling of the heat exchanger may be controlled based on reducing flash gas in the receiver (for example, by adjusting the proportion of fluid supplied to the primary and secondary channels of the heat exchanger). The degree of subcooling of the heat exchanger may also be controlled based on sensor readings and / or control signals supplied to a flash gas valve, which may further be based on flash gas in the receiver. In some embodiments, such a subcooled heat exchanger may receive the fluid output from a gas cooler or the fluid output from the subcooled heat exchanger as input to a secondary channel (for example, a channel containing a fluid that absorbs heat from the fluid in the primary channel).

[0021] In some embodiments, a pressure difference can be maintained between the receiver and the low-pressure subsystem of the PX (e.g., a low-pressure inlet and a low-pressure outlet). A control valve may be installed between the low-pressure outlet of the PX and the receiver. The controller may receive an indication of the pressure difference and provide a control signal to the control valve to adjust its operation, for example, to achieve a target pressure difference.

[0022] A system including a control valve for maintaining the pressure difference between the PX's low-pressure subsystem and the receiver may be combined with a system including a subcooler (the subcooler may have a second channel coupled to receive the fluid either before or after it flows through the subcooler's primary channel), a system including a low-pressure booster, a system including an auxiliary gas cooler, a system including a superheater, and so on. Combinations of these features may be included, for example, to tailor the system's characteristics for a target application.

[0023] The systems, apparatus, and methods of this disclosure offer advantages over conventional solutions. The systems of this disclosure can reduce energy consumption compared to, for example, conventional systems that do not include PX. For example, by using PX in the heat transfer system of this disclosure, the energy stored as pressure can be recovered and reintroduced into the system, thereby reducing the operating cost of the heat transfer system. This reduction in energy cost may allow for lower compressor rotation speeds and power consumption, or it may be possible to use a less expensive, smaller, and / or lower-power compressor in the system.

[0024] The various controllers used in the system are for maintaining target conditions and can increase the energy efficiency of the system, for example, by minimizing the work performed by the compressor to maintain the target temperature of the refrigeration zone associated with the fluid processing system. Energy efficiency can be improved, for example, by maximizing the pressure transfer from the first fluid to the second fluid via the PX (for example, by adjusting the fluid flow rate, fluid pressure, PX operating speed, etc.).

[0025] The systems of this disclosure can reduce the complexity of the fluid handling system by reducing the number of pumps (e.g., boosters) included in the system. For example, in the architecture of this disclosure, it may be possible to reduce one or more pumps or compressors so that the PX can perform some pressurizing and compression operations that would be performed by boosters in other architectures. Reducing the number of pumps or compressors can reduce the equipment cost of the system, reduce the number of parts to be serviced, and reduce the number of fault points to reduce system downtime or corrective or preventive maintenance. Specifically, some aspects of this disclosure include a subcooler, which may be used in architectures that do not include a low-pressure booster coupled to the low-pressure inlet of the PX.

[0026] Aspects of this disclosure may improve the efficiency of a fluid handling system by reducing the pumping requirements imposed on the system. For example, the supply flow provided to the receiver may contain a higher proportion of liquid in the architecture of this disclosure than in conventional systems. A higher liquid-phase proportion may reduce the requirement to compress the flash gas to perform heat transfer operations, thereby improving the efficiency of the system. By supplying the hot fluid from the high-pressure outlet of the PX to a superheater, auxiliary gas cooler, or other component, and reducing the temperature of the fluid before it is supplied to the receiver, the receiver may contain a higher mass proportion of liquid than in conventional architectures.

[0027] The system of this disclosure can reduce wear on components (e.g., pumps, compressors) compared to conventional systems. The introduction of PX can reduce the pumping load on one or more pumps / compressors, for example, by reducing the target pressure difference that the compressor must achieve. One or more controllers (e.g., control systems) can improve the operation of the pumps and compressors by enabling operation at a target pumping speed, which is, for example, a pumping speed (e.g., minimum allowable pumping speed) selected to protect one or more components of the system while meeting the target system output (e.g., maintaining the target temperature of the heat transfer system).

[0028] The systems of this disclosure can protect one or more components from damage. For example, the compressor of the system is sensitive to the phase of the substance supplied to the compressor (e.g., it may be configured to compress a gas and may be damaged if a liquid is supplied). A superheater may raise the temperature of the fluid supplied to one or more compressors of the system. The superheater may receive a hot fluid from the high-pressure outlet of a PX. This hot fluid may be supplied to the superheater to exchange heat with the fluid supplied to the compressor. In this case, the liquid may be less likely to be supplied to the compressor, and for example, the compressor may be protected from damaging input conditions. In other embodiments, a controller of the system may adjust one or more operating parameters of the system (e.g., fluid flow rate, pumping rate, operating speed of the PX, control valve opening, etc.) to maintain the supply of gas to the compressor (e.g., by maintaining a target superheat value for the gas). The systems of this disclosure can increase flexibility in the selection of components for a fluid handling system. For example, one or more controllers (e.g., control systems) may be operationally coupled and work together to maintain one or more operating conditions. For example, a system may include multiple controllers (e.g., control systems) operationally coupled to multiple components (e.g., configured to facilitate adjustment of one or more operating parameters of those components). Multiple control signals may be generated to achieve one or more target tasks. For example, the temperature of a region associated with a heat transfer system may be maintained, and the pump load may be kept within a target range. By utilizing multiple controllers in the system, such goals can be achieved, and / or the user may be able to use a wider selection of components in the system (e.g., a system in which the pump pressure can be maintained within a range under a variety of operating conditions may include pumps with a smaller manufacturer-recommended operating pressure range).

[0029] The system of this disclosure may enable control of one or more components of a fluid processing system while reducing the complexity of sensors and / or controls compared to some conventional architectures. An auxiliary high-pressure valve may be coupled between the high-pressure outlet and receiver of a PX and included in the architecture (e.g., for regulating fluid flow through an auxiliary gas cooler, regulating fluid flow through a superheater, etc.). Control of the auxiliary high-pressure valve may be based on the fluid characteristics provided to the valve, the fluid characteristics provided to the low-pressure inlet of the PX, or similar. In some cases, the operating speed of a component (e.g., the operating speed of the PX, the operating speed of a low-pressure booster, or similar) may be used to determine the fluid characteristics and the opening of the auxiliary high-pressure valve. In some cases, the opening of a different valve (e.g., the opening of a valve that determines fluid flow through a subcooler) may be used to determine the opening of the auxiliary high-pressure valve, for example, when the fluid conditions in the subcooler are comparable to the fluid conditions in the auxiliary high-pressure valve. In some embodiments, measurements from one or more flowmeters may be used to determine the opening of the auxiliary high-pressure valve. In some embodiments, existing sensors (e.g., for other purposes) on the PX subsystem of the refrigeration system (e.g., the parent rack) may be utilized, for example, temperature sensors and PX velocity measurements in a gas cooler may be used to determine the opening of an auxiliary high-pressure valve. In some embodiments (e.g., embodiments including a superheater heat exchanger), fluid temperature and PX velocity at the compressor inlet may be used to determine the opening of an auxiliary high-pressure valve.

[0030] While some embodiments of this disclosure are described in relation to pressure exchangers, energy recovery devices, and hydraulic energy transfer systems, this disclosure is also applicable to other systems and devices (e.g., non-isobaric pressure exchangers, non-rotating components, non-rotating pressure exchangers, systems without pressure exchangers, etc.).

[0031] While some embodiments of this disclosure are described in relation to pressure exchange between fluids used in fracing systems, desalination systems, heat pump systems, and / or refrigeration systems, this disclosure is also applicable to other types of systems. Fluids may refer to liquids, gases, transcritical fluids, supercritical fluids, subcritical fluids, and / or combinations thereof.

[0032] In some aspects of the present disclosure, the system comprises a pressure exchanger (PX) configured to receive a first fluid, receive a second fluid, and exchange pressure between the first and second fluids. The system further comprises a first heat exchanger configured to receive a second fluid from the PX via a first inlet, receive a third fluid via a second inlet, and exchange heat between the second and third fluids. The system further comprises a first compressor configured to receive a third fluid from the first heat exchanger.

[0033] In some aspects of the present disclosure, the method includes obtaining a characteristic representation of the working fluid of a refrigeration system supplied to the low-pressure inlet of a PX using a processing device. The method further includes generating a first control signal based on the characteristic representation of the working fluid at the low-pressure inlet of the PX. The method further includes providing the control signal to a high-pressure control valve fluidly communicating between the high-pressure outlet of the PX and a receiver. The high-pressure control valve is configured to adjust its operation based on the first control signal.

[0034] In some aspects of the present disclosure, the method includes obtaining, by a processing device, a representation of the pressure difference between a receiver of a refrigeration system and a low-pressure subsystem of a PX of the refrigeration system. The method further includes generating a first control signal based on the representation of the pressure difference. The method further includes providing the first control signal to a control valve, which is in fluid communication with the low-pressure outlet of the PX and the receiver. The control valve is configured to adjust its operation based on the first control signal.

[0035] Figure 1A illustrates a schematic diagram of a fluid processing system 100A (e.g., a heat transfer system, a refrigeration system) including a hydraulic energy transfer system 110 according to a specific embodiment.

[0036] In some embodiments, the hydraulic energy transfer system 110 may include a pressure exchanger (e.g., PX). The hydraulic energy transfer system 110 (e.g., PX, a set of components including PX, etc.) receives low-pressure (LP)in fluid 120 from the LPin system 122 (e.g., via a low-pressure inlet). The hydraulic energy transfer system 110 also receives high-pressure (HP)in fluid 130 from the HPin system 132 (e.g., via a high-pressure inlet). The hydraulic energy transfer system 110 (e.g., PX) exchanges pressure between the HPin fluid 130 and the LPin fluid 120, providing LPout fluid 140 to the LPout system 142 (e.g., via a low-pressure outlet) and also providing HPout fluid 150 to the HPout system 152 (e.g., via a high-pressure outlet). The fluid processing system 100A includes a protection and control component 182, for example, the architecture is designed to include one or more components for improved operation and control compared to other PX fluid processing systems, for example, compared to other PX heat transfer systems or refrigeration systems. The protection and control component 182 may include one or more additional heat exchangers, for example, one or more additional heat exchangers for providing superheat to the working fluid supplied to the compressor of the fluid processing system 100A. The protection and control component 182 may include an auxiliary high-pressure valve and an associated control architecture. The protection and control component 182 may include a valve for maintaining the pressure difference between the low-pressure subsystem of the PX and the receiver of the fluid processing system 100A.

[0037] The controller may regulate the flow rate and / or conditions of the HPin fluid 130 and the LPout fluid 140 by one or more flow valves, pumps, motors, fans, and / or compressors (not shown). The controller may be configured to perform various operations (e.g., of controllable components included in the fluid processing system 100A). The controller may be configured to trigger the operation of one or more valves. The controller may be configured to trigger adjustments to the operating speed of one or more components. The controller may trigger other operations of controllable components of the fluid processing system 100A. The controller may actuate one or more valves. The controller may start, stop, or regulate the operation of one or more pumps. The controller may start, stop, or regulate the operation of components that regulate heat transfer between the working fluid and the fluid processing system 100A. For example, the controller may start a fan that increases heat transfer from the working fluid to the ambient environment via one or more gas coolers.

[0038] In some embodiments, the hydraulic energy transfer system 110 includes a PX that exchanges pressure between the HPin fluid 130 and the LPin fluid 120. In some embodiments, the PX may be substantially or partially isobaric (e.g., an isobaric pressure exchanger (IPX)). The PX may be a device that transfers fluid pressure between the HPin fluid 130 and the LPin fluid 120, and its efficiency (e.g., substantially isobaric pressure transfer efficiency) may be greater than or equal to about 50%, 60%, 70%, 80%, or 90% (e.g., without using centrifugal technology). High pressure (e.g., HPin fluid 130, HPout fluid 150) refers to a pressure greater than low pressure (e.g., LPin fluid 120, LPout fluid 140). In some cases, the LPin fluid 120 in the PX is pressurized and flows out of the PX at high pressure (e.g., HPout fluid 150 at a higher pressure than the LPin fluid 120), while the HPin fluid 130 is at least partially depressurized and flows out of the PX at low pressure (e.g., LPout fluid 140 at a lower pressure than the HPin fluid 130). The PX can operate in such a way that the HPin fluid 130 directly applies a pressurizing force to the LPin fluid 120, with or without a fluid separator between the fluids. Examples of fluid separators that may be used with the PX include, but are not limited to, pistons, bladders, and diaphragms.

[0039] In some embodiments, the PX may be a rotary device. For example, a rotary PX like the one manufactured by Energy Recovery Inc. in San Leandro, California, may not have any separate valves at all. This is because substantial valve action is achieved within the device through the relative motion of the rotor with respect to the end cover. In some embodiments, the rotary PX may operate using an internal piston to separate fluids and transmit pressure while minimizing mixing of the inlet fluid flow. In some embodiments, the rotary PX operates without an internal piston between the fluids.

[0040] In some embodiments, the PX may be a reciprocating device. A reciprocating PX may include a piston that moves back and forth within a cylinder to transfer pressure between fluid flows. For example, a reciprocating PX may include one or more pressure exchange chambers. Each pressure exchange chamber may include a piston. A high-pressure first fluid may flow into one side of the pressure exchange chamber and transfer energy (e.g., via the displacement of the piston) to a low-pressure second fluid on the opposite side of the pressure exchange chamber. The low-pressure first fluid can then be discharged from the pressure exchange chamber, while the high-pressure second fluid can be used for the operation of the fluid processing system (e.g., for desalination, fracing, refrigeration, heat transfer, or similar applications). The low-pressure second fluid can then fill the second side of the pressure exchange chamber, after which the high-pressure first fluid can be introduced into the first side of the pressure exchange chamber and transfer energy to the other part of the second fluid. A reciprocating device may comprise multiple pressure exchange chambers and operate in a cycle to achieve a substantially continuous flow of a high-pressure second fluid from the device.

[0041] In some embodiments, PX may be a hydraulic turbocharger. A hydraulic turbocharger PX may introduce a high-pressure first fluid into a chamber containing a first impeller. The high-pressure first fluid can rotate the impeller by energy transfer from the first fluid to the impeller. The first impeller is coupled to a shaft, which may also be coupled to a second impeller in a separate chamber. The rotation of the first impeller may cause the rotation of the second impeller. The second impeller may come into contact with a low-pressure second fluid. The rotation of the impeller may transfer energy to the second fluid (for example, by increasing the pressure of the second fluid).

[0042] In this disclosure, any or more PXs may be used, for example, rotary PXs, reciprocating PXs, hydraulic turbocharger PXs, or any combination thereof. Furthermore, the PXs may be placed on skids separate from the other components of the fluid handling system 100A (for example, in situations where PXs are added to an existing fluid handling system). For example, a PX may be fixed to a structure that is movable from one location to another. A PX may be coupled to a system constructed on-site (for example, the piping of a system). The structure to which a PX is fixed may be referred to as a “skid.”

[0043] In some embodiments, the motor 160 may be coupled to a hydraulic energy transfer system 110 (e.g., to a PX). In some embodiments, the motor 160 controls the speed of the rotor of the hydraulic energy transfer system 110 (e.g., to increase the pressure of the HPout fluid 150, or to decrease the pressure of the HPout fluid 150). In some embodiments, the motor 160 generates energy based on pressure exchange in the hydraulic energy transfer system 110 (e.g., to act as a generator). For example, a pressure difference (e.g., the difference between the pressure of the LPin fluid 120 and the pressure of the HPin fluid 130) can drive the rotation of a rotary PX, and the motor 160 can introduce resistance to its rotation to decelerate the rotation and generate electricity. Alternatively, the motor may operate to decelerate the PX without generating electricity.

[0044] The hydraulic energy transfer system 110 may include a hydraulic turbocharger or hydraulic pressure exchanger, such as a rotary PX. The PX may include one or more chambers and / or channels (e.g., 1 to 100 channels) to facilitate pressure transfer between a first fluid and a second fluid (e.g., a gas, liquid, multiphase fluid, supercritical fluid, etc.).

[0045] In some embodiments, the hydraulic energy transfer system 110 can transfer energy (e.g., pressure) between two fluids that are substantially different in composition, phase, or similar respects. For example, the PX of the hydraulic energy transfer system 110 can transfer pressure between a first fluid (e.g., a pressure exchange fluid, such as a first-phase fluid like a liquid or supercritical fluid, a propane-free fluid, a substantially propane-free fluid, a low-viscosity fluid, a fluid in which a specific chemical is below a predetermined threshold amount, etc.) and a second fluid, which may be in a different phase, have a higher viscosity (e.g., be high viscosity), contain a specific chemical (e.g., a corrosive chemical) above a predetermined threshold amount, and / or contain solid particles (e.g., a fracking fluid including sand, propane, powder, fragments, ceramics, etc.). By transferring energy from one type of fluid to another, expensive components such as pumps can sometimes be protected from contact with fluids that could be harmful to them (e.g., highly viscous, corrosive, or abrasive fluids, or fluids in phases that the components are not designed to process).

[0046] In some embodiments, the hydraulic energy transfer system 110 can transfer energy (e.g., pressure) between two fluids having substantially similar compositions. For example, in some conventional systems, the waste flow of the system may contain a high-pressure fluid. The hydraulic energy transfer system 110 can accept this high-pressure waste flow as a high-pressure input (e.g., HPin fluid 130) and transfer energy from that flow to a low-pressure working flow (e.g., LPin fluid 120). In some systems, for example in a closed-loop refrigeration system, energy can be recovered from the high-pressure portion of the fluid flow, reducing the requirements for pumps and / or compressors for that flow.

[0047] In some embodiments, the LPin system 122 receives gas from the LPout system 142. In many embodiments, the LPin system 122 receives fluid from a receiver (e.g., a flush tank). This receiver may receive the LPout fluid 140 discharged from the hydraulic energy transfer system 110.

[0048] The fluid processing system 100A further includes a control module. The control module may include one or more controllers. The control module may be configured to perform any of the methods shown in Figures 5A to 5E. The controllers of the control module may receive data (e.g., measurement data) from sensors associated with the fluid processing system 100A. The controllers may be configured to generate control signals based on operating parameters (e.g., thresholds, specified operating ranges, target parameter values, etc.) and / or data received from sensors. The controllers may include a single device that performs one or more control tasks, a separate device for each control task (e.g., each controllable component of the fluid processing system 100A), a plurality of devices, each performing multiple functions, etc. For example, the operation of each controller may be performed by a separate device, or the operation of all controllers may be performed by a single device, or a combination of individual and integrated devices may be employed. The components of a control module may include general-purpose computing devices, personal computers (PCs), laptops, mobile phones, tablet computers, netbooks, microcontrollers, custom-designed controllers (e.g., hardware, circuits, etc.), proportional-integral-derivative (PID) controllers (e.g., ternary controllers), web appliances, or any other device capable of executing a set of commands (whether periodic or not) that specify the actions the device should perform. A control module may include multiple controllers that operate independently (e.g., no input between one controller and another, measurement data from one sensor is not provided to multiple controllers, etc.). A control module may include multiple controllers that operate in conjunction with each other. For example, target adjustment of the operating parameters of the fluid processing system 110A (e.g., those reported by one or more sensors in the system) may include adjustment of the operation of one or more components of the system by one or more controllers of the control module.

[0049] The fluid processing system 100A may further include one or more sensors that provide sensor data associated with the fluid in the fluid processing system 100A (e.g., flow rate data, pressure data, velocity data, etc.). The controller of the fluid processing system 100A may control one or more flow rates of the fluid processing system 100A, the operation of one or more components of the fluid processing system 100A (e.g., the operation of the motor 160, the operation of one or more pumps, etc.), or similar based on the sensor data. In some embodiments, the controller may actuate one or more flow valves based on the received sensor data.

[0050] The hydraulic energy transfer system 110 can be used in various types of systems, such as fracing systems, desalination systems, refrigeration systems (e.g., Figure 1B), heat pump systems, slurry pump systems, industrial fluid systems, waste fluid systems, and fluid transport systems.

[0051] The controller of the control module may provide control signals to interdependent components of the fluid processing system 100A. For example, the controller may provide a control signal to the motor 160 to control the operating speed of the hydraulic energy transfer system 110. The operating speed of the hydraulic energy transfer system 110 may further affect conditions at other locations in the fluid processing system 100A. Other components, such as valves and pumps, may be operated to control conditions of the fluid processing system 100A that are affected by the operating speed of the hydraulic energy transfer system 110. The controller may provide signals to various controllable components included in the fluid processing system 100A. Various components of the subsystems of the fluid processing system 100A may be controlled by signals provided by the controller based on the operating speed of the hydraulic energy transfer system 110.

[0052] Figure 1B illustrates a schematic diagram of a fluid processing system 100B, including a hydraulic energy transfer system 110, according to a particular embodiment. The fluid processing system 100B may be, for example, a heat transfer system, a refrigeration system, or a heat pump system. The fluid processing system 100B may be configured to cool and / or heat an environment (e.g., an indoor space, a refrigeration device, a freezer, etc.). In some embodiments, the fluid processing system 100B may include more or fewer components, the same or different routing configurations, and / or similar configurations than those shown in Figure 1B. Features in Figure 1B that have the same reference numerals as those in Figure 1A may have similar characteristics, functions, and / or structures as those in Figure 1A.

[0053] In some embodiments, the components of the fluid processing system 100B may be configured to eliminate one or more lift devices for increasing pressure in relation to one or more of the LPin system 122 or HPout system 152. HPin fluid 130 may be supplied from the HPin system 132 (including, for example, a condenser 138, a gas cooler, a heat exchanger, etc.) to the hydraulic energy transfer system 110. The hydraulic energy transfer system 110 (e.g., PX) may exchange pressure between the LPin fluid 120 and the HPin fluid 130, supply HPout fluid 150 to the HPout system 152 (e.g., any high-pressure lift device, a high-pressure fluid pump, a high-pressure compressor, etc.), and supply LPout fluid 140 to the LPout system 142 (e.g., an evaporator 144, a heat exchanger, etc.). In some embodiments, the components of the fluid processing system 100B may be configured to eliminate high-pressure lift devices, for example, in some architectures, high-pressure lift devices are optional components. The LPout system 142 (e.g., evaporator 144) may supply fluid to the compressor 178 and / or optionally to the low-pressure lift device. The evaporator 144 may supply fluid to the compressor 178 and / or optionally to the low-pressure lift device. In some embodiments, other components may supply fluid to the low-pressure lift device, evaporator 144, etc. For example, the LPout fluid 140 may be supplied to the receiver of the flash tank. The liquid discharged from the flash tank may be supplied to the evaporator 144. In some embodiments, additional valves, lines, piping, fluid passages, etc., may supply fluid to different devices in different orders and / or combinations. The condenser 138 may receive fluid from the compressor 178. The controller may control one or more components of the fluid handling system 100B, including the motor 160 and various other controllable components.

[0054] The fluid processing system 100B may be a closed system. The LPin fluid 120, HPin fluid 130, LPout fluid 140, and HPout fluid 150 may all be fluids (e.g., refrigerant, the same fluid) that circulate within the fluid processing system 100B.

[0055] The fluid processing system 100B may further include one or more sensors configured to provide sensor data associated with the system. For example, a sensor may report the properties of the fluid at various stages of the system (e.g., various components of the system), namely temperature, pressure, flow rate, density, etc. A sensor may also measure properties related to the function of the fluid processing system 100B. For example, a refrigeration system may include one or more temperature sensors that report the temperature of the area to be refrigerated. A sensor may also measure properties that affect the operation of the fluid processing system 100B. For example, a heat transfer system intended to heat an area associated with a condenser 138 may measure the temperature near the evaporator 144, and may use the temperature measurement near the evaporator 144 to adjust one or more operating parameters of the fluid processing system 100B, for example, to achieve a target output (e.g., temperature), to improve operating efficiency, or for similar purposes.

[0056] The protective component 133 may be configured to be incorporated into either the architecture shown in Figures 3A-3C or the method shown in Figures 5A-5B. The controller of the fluid processing system 100B may receive sensor data from the sensor (e.g., raw sensor data, pre-processed sensor data, averaged sensor data, data as the difference of measured values ​​from a target value / threshold, etc.). The controller of the fluid processing system 100B may be configured to generate one or more control signals based on the input sensor data. The control signals may facilitate the operation of the tunable components of the fluid processing system 100B.

[0057] The fluid processing system 100B may include one or more valves with variable openings. For example, the fluid flow rate may be changed by adjusting the opening of the valves. The valves may be electronically adjustable, for example, an electronic expansion valve (EEV). The valves may be configured to adjust their opening (e.g., a percentage value of the opening) based on a control signal received from a control module coupled to one or more components of the fluid processing system 100B. The fluid processing system 100B may include one or more pumps, compressors, or similar devices. The pumps and compressors may be configured to have variable operating speeds (e.g., motor operating speed, pumping speed, etc.). The pumps and compressors may be configured to adjust their operating speeds based on control signals received from a control module. The fluid processing system 100B may include a motor 160 coupled to the PX of the hydraulic energy transfer system 110. The motor 160 may be configured to adjust the operating speed of the PX based on a signal received from a control module. For example, motor 160 can operate as a generator by converting the rotational energy of PX into electrical energy.

[0058] Figures 2A-2E are exploded perspective views of a rotary PX40 (e.g., a rotary pressure exchanger, a rotary liquid piston compressor (LPC)) according to a particular embodiment. Some of the features of one or more of Figures 2A-2E may have similar characteristics, functions, and / or structures to one or more of the features of Figures 1A-1B.

[0059] The PX40 may be configured to transmit pressure and / or work between a first fluid (e.g., refrigerant, supercritical carbon dioxide, HPin fluid 130) and a second fluid (e.g., refrigerant, superheated vaporized carbon dioxide, LPin fluid 120) with minimal fluid mixing. The rotary PX40 may include a generally cylindrical body 42, which includes a sleeve 44 (e.g., rotor sleeve) and a rotor 46. The rotary PX40 may also include two end caps 48 and 50, which include manifolds 52 and 54, respectively. Manifold 52 includes its respective inlet port 56 and outlet port 58, while manifold 54 includes its respective inlet port 60 and outlet port 62. During operation, these inlet ports 56, 60 allow the first and second fluids to flow into the rotary PX40 and exchange pressure, while the outlet ports 58, 62 allow the first and second fluids to subsequently flow out of the rotary PX40. During operation, the inlet port 56 receives a high-pressure first fluid (e.g., HPin fluid 130) discharged from the condenser, and after pressure exchange, the outlet port 58 may be used to route the low-pressure first fluid (e.g., LPout fluid 140) flowing out from the rotary PX40 to a receiver (e.g., a flash tank) configured to receive the first fluid from the PX40. The receiver may form a chamber configured to separate the fluid into gas and liquid. Similarly, the inlet port 60 may be used to receive a low-pressure second fluid (e.g., low-pressure slurry fluid, LPin fluid 120) from a booster configured to receive the gaseous portion from the receiver and increase the pressure of the gas, and the outlet port 62 may be used to route a high-pressure second fluid (e.g., high-pressure slurry fluid, HPout fluid 150) from the rotary PX40. The end caps 48 and 50 each include end covers 64 and 66 (e.g., end plates) located within the respective manifolds 52 and 54, which enable fluid sealing contact with the rotor 46.

[0060] The ports of the PX are in fluid communication with a fluid system, which includes a fluid processing architecture 92. The fluid processing architecture 92 includes several components for performing operations, regulating fluid conditions, providing system control, etc., such as the components described in relation to Figures 1A-1B. The fluid processing architecture 92 may include protective and control components 182, which may include one or more components that enable the removal or bypass of one or more pumps or compressors in the fluid processing architecture 92. For example, components such as a heat exchanger and / or receiver may enable the removal of one or more booster pumps compared to other PX fluid systems. Further discussion of architectures including one or more protective and other controllable components can be found in relation to Figures 3A-3C and 4A-4B.

[0061] One or more components of the PX40, such as the rotor 46, end cover 64 and / or end cover 66, may be made of a wear-resistant material (e.g., carbides, cemented carbide, silicon carbide, tungsten carbide, etc.) having a hardness higher than a predetermined threshold (e.g., Vickers hardness of at least 1000, 1250, 1500, 1750, 2000, or 2250). For example, tungsten carbide may have higher durability and improved wear resistance to abrasive fluids compared to other materials such as alumina ceramics. One or more components of the PX40, such as the rotor 46, end cover 64 and / or end cover 66, and / or other sealing surfaces of the PX40 may be provided with inserts. In some embodiments, the insert may be made of a wear-resistant material (e.g., carbides, cemented carbides, silicon carbides, tungsten carbides, etc.) having a hardness higher than a predetermined threshold (e.g., Vickers hardness of at least 1000, 1250, 1500, 1750, 2000, 2250 or higher) in order to improve wear resistance.

[0062] The rotor 46 is cylindrical and may be housed within a sleeve 44, thereby allowing the rotor 46 to rotate around an axis 68. The rotor 46 has a plurality of channels 70 (e.g., ducts, rotor ducts) that penetrate substantially longitudinally through the rotor 46, and openings 72 and 74 (e.g., rotor ports) may be symmetrically arranged at each end around the longitudinal axis 68. The openings 72 and 74 of the rotor 46 are arranged to communicate fluidly with inlet apertures 76 and outlet apertures 78 (e.g., end cover inlet ports and end cover outlet ports) and 80 and 82 (e.g., end cover inlet ports and end cover outlet ports) of the end covers 64 and 66, in such a manner that the channels 70 are exposed to high-pressure and low-pressure fluids during rotation. As shown in the figure, the inlet apertures 76 and outlet apertures 78, 80 and 82 may be designed in the shape of an arc or a part of a circle (e.g., C-shape).

[0063] The operating speed of the PX40 may be used to control the degree of mixing between the first fluid and the second fluid within the rotary PX40, which can be used to improve the operability of the fluid processing system (e.g., fluid processing system 100A-B in Figure 1A-1B). For example, by changing the volumetric flow rate of the first and / or second fluids flowing into the rotary PX40, the operator (e.g., system operator, plant operator) can control the amount of fluid mixing within the PX40. Furthermore, by changing the rotational speed of the rotor 46 (e.g., via a motor), the operator can also control the mixing. Three features of the rotary PX40 that affect the mixing are (1) the aspect ratio of the rotor channel 70, (2) the exposure time between the first and second fluids, and (3) the creation of a barrier (e.g., fluid barrier, piston, interface) between the first and second fluids within the rotor channel 70. Firstly, because the rotor channel 70 (e.g., a duct) is generally long and narrow, the flow within the rotating PX40 is stabilized. Furthermore, the first and second fluids may move through the channel 70 in a plug flow manner, minimizing axial mixing. Secondly, in certain embodiments, the speed of the rotor 46 reduces contact between the first and second fluids. For example, the speed of the rotor 46 (e.g., a rotor speed of about 1200 revolutions per minute (RPM)) may reduce the contact time between the first and second fluids to less than about 0.15 seconds, 0.10 seconds, or 0.05 seconds. Thirdly, the rotor channel 70 (e.g., a small portion of the rotor channel 70) is used to exchange pressure between the first and second fluids. In some embodiments, a certain amount of fluid remains in the channel 70 as a barrier between the first and second fluids. Any such mechanism may limit mixing within the rotating PX40. Furthermore, in some embodiments, the rotary PX40 may be designed to operate using all or part of an internal piston, or other barriers, to isolate the first fluid from the second fluid while allowing pressure transmission.

[0064] In some embodiments, the operating speed of PX can be set (for example, to target the characteristics listed above, or other characteristics of interest to the fluid system). The characteristics of the fluid system may be affected by the rotational speed of PX40. The control module receives an indication of the operating speed of PX40 (for example, from a sensor, from a control signal for the controller of PX40, etc.) and may generate control signals for the controllable components of the fluid processing architecture 92 based on the operating speed of PX40.

[0065] Figures 2B to 2E are exploded views of one embodiment of the rotary PX40, showing the sequence of positions of a single rotor channel 70 within the rotor 46 when the channel 70 rotates in a complete cycle. Note that Figures 2B to 2E are simplified diagrams of the rotary PX40, showing one rotor channel 70, and the channel 70 is shown as having a circular cross-sectional shape. In other embodiments, the rotary PX40 may comprise multiple channels 70 having the same or different cross-sectional shapes (e.g., circular, elliptical, square, rectangular, polygonal, etc.). For this reason, Figures 2B to 2E are simplified for illustrative purposes, and other embodiments of the rotary PX40 may have configurations different from those shown in Figures 2A to 2E. As will be described in detail below, the rotary PX40 facilitates pressure exchange between a first fluid and a second fluid (e.g., a particulate-free fluid and a slurry fluid, a high-pressure refrigerant and a low-pressure refrigerant, etc.) by allowing the first fluid and the second fluid to come into contact with each other for a short time within the rotor 46. In some embodiments, PX facilitates pressure exchange between the first and second fluids by allowing the first and second fluids to come into contact on opposite sides of a barrier (e.g., a reciprocating barrier, a piston; not shown). In some embodiments, this exchange occurs at a rate that limits the mixing of the first and second fluids. The velocity of the pressure wave passing through the rotor channel 70 (as soon as the channel is exposed to the aperture 76), the fluid diffusion velocity, and the rotational speed of the rotor 46 determine whether, and to what extent, mixing occurs.

[0066] Figures 2B-2E include a protective and control component 182 as part of a fluid system that is fluid-communicated to one or more outlets of PX40. The protective and control component 182 may allow for the removal of one or more pumps or compressors (e.g., low-pressure boosters and / or high-pressure boosters) from the fluid handling system, as described in relation to Figure 1A.

[0067] The controllable components of the fluid processing system coupled to PX, shown in Figures 2B-2E, may provide control signals according to one of the methods shown in Figures 5A-5B. Figures 2B-2E illustrate the various stages of operation of PX40. The operation of PX40 may be controlled by a control module. For example, the control module may be operationally coupled to the motor of PX. The control module may transmit one or more control signals to the motor. The motor may adjust the operation of PX40, for example, by adjusting the rotational speed of PX40. The control module may be operationally coupled to other components of the fluid processing system that affect the operation of PX40. For example, one or more compressors supplying fluid to PX40 may be controlled by the control module, one or more valves supplying fluid to PX40 may be controlled by the control module, and one or more valves coupled to the outlet of PX40 may be controlled by the control module. These components may include the controllable components described in relation to the architecture of Figures 3A-3C. These controllable components may be associated with control via the methods described in conjunction with Figures 5A-5B.

[0068] Figure 2B is an exploded perspective view of one embodiment of a rotary PX40 (e.g., rotary LPC) according to a particular embodiment. In Figure 2B, the channel opening 72 is in a first position. In the first position, the channel opening 72 is in fluid communication with the aperture 78 of the end cover 64 and, consequently, with the manifold 52, while the opposite channel opening 74 is in fluid communication with the aperture 82 of the end cover 66, and from there extends to the manifold 54. The rotor 46 may rotate in the clockwise direction indicated by the arrow 84. During operation, a low-pressure second fluid 86 (e.g., a low-pressure slurry fluid) flows through the end cover 66 into the channel 70, where it comes into contact with the first fluid 88 at the dynamic fluid interface 90. The second fluid 86 then pushes the first fluid 88 out of the channel 70 through the end cover 64 and out of the rotary PX40. However, due to the short contact time, mixing between the second fluid 86 (e.g., a slurry fluid) and the first fluid 88 (e.g., a particle-free fluid) is minimal. In some embodiments, the low-pressure second fluid 86 contacts a first side of a barrier (e.g., a piston; not shown) located within the channel 70, and the barrier contacts the first fluid 88 (e.g., on the opposite side of the barrier). The second fluid 86 drives the barrier, pushing the first fluid 88 out of the channel 70. In such embodiments, mixing between the second fluid 86 and the first fluid 88 is negligible.

[0069] Figure 2C is an exploded perspective view of one embodiment of a rotary PX40 (e.g., rotary LPC) according to a particular embodiment. In Figure 2C, the channel 70 is rotated clockwise in an arc of approximately 90 degrees. In this position, the opening 74 (e.g., the outlet) is not in fluid communication with the apertures 80 and 82 of the end cover 66, and the opening 72 is not in fluid communication with the apertures 76 and 78 of the end cover 64. Therefore, the low-pressure second fluid 86 is temporarily contained within the channel 70.

[0070] Figure 2D is an exploded perspective view of one embodiment of a rotary PX40 (e.g., rotary LPC) according to a specific embodiment. In Figure 2D, the channel 70 is rotated in an arc of approximately 60 degrees from the position shown in Figure 2B. The opening 74 here is in fluid communication with the aperture 80 of the end cover 66, and the opening 72 of the channel 70 here is in fluid communication with the aperture 76 of the end cover 64. At this position, a high-pressure first fluid 88 flows in, pressurizing a low-pressure second fluid 86, and pushing the second fluid 86 out of the rotor channel 70 through the aperture 80.

[0071] Figure 2E is an exploded perspective view of one embodiment of a rotary PX40 (e.g., rotary LPC) according to a particular embodiment. In Figure 2E, the channel 70 has rotated in an arc of approximately 270 degrees from the position shown in Figure 2B. At this position, the opening 74 is no longer in fluid communication with the apertures 80 and 82 of the end cover 66, and the opening 72 is no longer in fluid communication with the apertures 76 and 78 of the end cover 64. As a result, the first fluid 88 is no longer pressurized and is temporarily held in the channel 70 until the rotor 46 rotates another 90 degrees and the cycle is restarted.

[0072] Figures 3A-3C and 4A-4B are schematic diagrams of fluid processing systems 300A-300C and 400A-400B, including PX, according to a particular embodiment. Some features in one or more of Figures 3A-3C may have similar characteristics, functions, and / or structures to features in one or more of Figures 1A-1B and / or Figures 2A-2E (e.g., features with similar names and / or reference numerals). A system in one or more of Figures 3A-3C may be used to perform one or more of the methods in Figures 5A-5B. Some features in one or more of Figures 3A-3C may have similar characteristics, properties, functions, and / or structures to features in one or more of Figures 4A-4B. A system in one or more of Figures 4A-4B may be used to perform one or more of the methods in Figures 5A-5B.

[0073] Figures 3A-3C and 4A-4B show various fluid processing system architectures (fluid processing systems 300A-300C and 400A-400B) and various controllers according to specific embodiments. The shown architectures are exemplary and, for example, highlight the operation of the controllers in the fluid processing system. Any controllers shown in Figures 4A-4B may be included in any combination in any architectural design of a fluid processing system. For example, a controller performing an operation like controller 490 in Figure 4A may be included in another architecture not shown (e.g., fluid processing system 300C in Figure 3C), and a controller performing an operation like controller 492 controlling a valve in Figure 4B may be included in an architecture similar to that shown in Figure 3A. A fluid processing system including any controller shown herein (e.g., any controller that modulates the operation of components of a fluid processing and / or energy transfer system, including PX, based on sensor data from the system), either alone or in any combination, is within the scope of this disclosure. Controllers can be separate components (for example, each controller can be a separate device), or they can be combined components (for example, the operation of two or more controllers is performed by the same device or control system), and so on. Controllers can provide control signals in response to various inputs, for example, in response to sensor data provided to the controller. Controllers may also provide control signals to adjust the characteristics of a fluid processing system, for example, to adjust the value of one or more conditions of the fluid processing system so that the condition value satisfies one or more threshold conditions.

[0074] In some embodiments, the devices of the fluid processing systems 300A-300C and 400A-400B shown in Figures 3A-3C and 4A-4B may communicate via wired connections. In some embodiments, the devices of these fluid processing systems may communicate wirelessly. In some embodiments, the devices shown in Figures 4A-4B may communicate via a network. For example, the controllers in Figures 4A-4B may receive sensor data via a network and transmit control signals via the same network. In some embodiments, the devices of the fluid processing systems 400A-400B shown in Figures 4A-4B may communicate via one or more wired networks. In some embodiments, the devices of the fluid processing systems 400A-400B shown in Figures 4A-4B may communicate via one or more wireless networks (e.g., personal area network, wireless local area network, etc.). In some embodiments, the devices of the fluid processing systems 400A-400B may communicate partially via wired networks and partially via wireless networks.

[0075] In some embodiments, the controller of the fluid processing system 400A-400B may be a PID controller. The controller of the fluid processing system 400A-400B may calculate an error value (e.g., the difference between a target setpoint and a measured value). The controller of the fluid processing system 400A-400B may apply corrections based on the proportional, integral, and derivative terms of the error value (e.g., generate a control signal). For example, the proportional term may be based on the difference between the setpoint and the measured value, the integral term may be based on the value of the error term in the past integrated over time, and the derivative term may be based on a prediction of the future trend of the error term based on the rate of change of the current error term. In some embodiments, the controller of the fluid processing system 400A-400B may be a computing device. The controller of the fluid processing system 400A-400B may be implemented as software (e.g., executed by a general-purpose computing device), hardware, or a combination of hardware and software. In some embodiments, the operation of the controller of the fluid processing system 400A-400B may include receiving one or more adjustable setpoints, parameters, etc. For example, the controller's response (e.g., the magnitude of the output signal, the value of the adjustment command included in the control signal, etc.) may be variable in strength (e.g., for a given difference between a measured value and a target value for a particular measurement characteristic, the controller may have a range of possible output values, one of which may correspond to one or more setpoints and / or parameters of the controller). In some embodiments, the controller may have a corresponding lookup table, and for a given input (e.g., the difference between a setpoint and a measured value), the controller may generate an output according to the table. In some embodiments, the controller may perform calculations involving adjustable parameters (e.g., user-adjustable parameters, adjustable setpoints, etc.), and in response to the input, the controller may generate an output based on the input. In some embodiments, the controller's parameters and / or setpoints may be selected / adjusted by the user. In some embodiments, the controller's parameters and / or setpoints may be adjusted, for example, by the controller itself, the associated computing device, or the computer implementation method.

[0076] In some embodiments, the performance of the controller can be tracked (e.g., measured and stored over time). If the controller causes overshoot beyond a threshold (e.g., a percentage of the difference between an initial value and a target value that exceeds a threshold for the frequency and / or intensity of overshoot) (e.g., if a component of the fluid processing system overcompensates in response to receiving a control signal from the controller, causing the measured characteristic value to pass the target value before settling within the threshold range of the target value), the sensitivity of the controller (e.g., the strength of the response to measured values ​​different from the target characteristic value) can be reduced. For example, the controller may generate a control signal in response to receiving a measured value different from the setpoint (e.g., the difference between the setpoint and the measured value exceeds a threshold). Subsequently, the controller may receive a different measured value in the opposite direction to the setpoint (e.g., if the control signal was intended to compensate for a measured value lower than the setpoint, but a subsequent measured value is higher than the setpoint). The responsiveness of the controller (e.g., parameters in calculations that determine the strength of the output in response to an input such as the difference between the setpoint and the measured value, or table entries that determine the severity of the action commanded in the control signal based on the input from the sensor) can be adjusted to reduce the possibility of overshoot in future operation. Adjustments to the controller setpoint can be global, for example, by updating parameters or tables so that all future control signals are generated in accordance with that update. Adjustments to the controller setpoint may not be applied globally, for example, one or more lookup table values ​​may be adjusted while others are not (e.g., lookup table values ​​associated with a range of differences between the setpoint and the measured value may be adjusted, or lookup table values ​​associated with one or more differences in a range of measured values ​​may be adjusted), or parameters used in certain situations may be updated (e.g., a list of parameters may apply for different measured values, different setpoints, or different values ​​of the difference between the measured value and the setpoint), and so on.

[0077] Similarly, if the controller's sensitivity is insufficient (for example, if a characteristic value in the system takes longer than desired to reach a value within the threshold of the target value), the controller's response may be increased. For example, the controller may receive a measurement that differs from the setpoint (for example, the controller is configured to receive a pressure measurement from a pressure gauge and may receive a measurement that differs from the set pressure value by at least a threshold amount). The controller may generate a control signal in response to receiving such a measurement (for example, the controller may generate a control signal to open a valve to regulate the pressure in the pressure gauge). The controller may then receive a measurement indicating that the pressure has not reached the setpoint (for example, if the action taken by the valve in response to the control signal was insufficient to reduce the difference between the setpoint and the measurement to below a threshold). One or more setpoints / parameters of the controller may be adjusted to increase the controller's response to input (for example, increasing the output signal generated based on an input signal of a given strength, or increasing the strength of a command included in the control signal associated with a given difference between the setpoint and the measurement).

[0078] In some embodiments, determining the controller's sensitivity and / or response (e.g., output strength or updates to parameters or setpoints defining the strength) can be performed by a machine learning model. The machine learning model may be trained with inputs including target characteristic values, measured characteristic values, controller responses (e.g., control signals), and / or the results of actions taken by system components based on commands received by the controller. Once trained, the machine learning model may be configured to take measured characteristic values ​​and target values ​​as inputs and generate outputs indicating appropriate actions (e.g., control signals) that one or more components of the fluid processing system should take. For example, the machine learning model may be provided with historical data as training data. The machine learning model may be provided with one or more historical characteristic values ​​associated with the characteristics to be corrected in the fluid processing system (e.g., one or more setpoints and one or more measurements generated before and after system components act according to controller commands) as training inputs. The machine learning model may further be provided with historical characteristic values ​​after adjustments have been made to correct the measured characteristic values ​​(e.g., one or more measurements taken after control signals have been generated for one or more components of the system). The machine learning model may be provided with one or more historical control signals (or data indicating such control signals) as target outputs. Once trained, a machine learning model can take current characteristic values ​​(e.g., one or more setting values, one or more measured values, etc.) as input and generate a control signal (or data associated with a control signal) as output that predicts bringing one or more measured characteristic values ​​within a threshold difference of one or more setting values.

[0079] Fluid processing systems 300A-300C and 400A-400B may be heat transfer systems. Fluid processing systems 300A-300C and 400A-400B may be refrigeration systems. Fluid processing systems 300A-300C and 400A-400B may be heat pump systems. Fluid processing systems 300A-300C and 400A-400B may be reversible heat pump systems. Reversible heat pump systems may include components not shown in Figures 3A-3C, such as reversing valves (e.g., four-way valves for reversing flow). Reversible heat pump systems may reverse the direction of refrigerant fluid flow in one or more parts of the fluid processing system, for example, the flow through condensers and / or evaporators (e.g., outdoor heat exchange units and / or indoor heat exchange units) may be reversed. A reversible heat pump system may not reverse the direction of flow in one or more parts of the fluid processing system; for example, the flow through a compressor or pump may not be reversed. A reversible heat pump system may include, for example, additional flow channels, additional valves, etc., that are used when the flow is reversed. Additional components and flow channels associated with a reversible heat pump system are not shown in Figures 3A-3C, but a reversible heat pump system including such components is within the scope of this disclosure.

[0080] Figure 3A is a schematic diagram of a fluid processing system 300A, according to several embodiments, which includes a PX310 and a subcooler 315 and a superheater 311, which are heat exchangers that exchange heat between the working fluid flow. The fluid processing system 300A may be configured to control various components of the system based on sensor data received from sensors of the system. The fluid processing system 300A may be configured to determine the opening of one or more valves, at least in part, based on the operating speed of the PX310. The fluid processing system 300A may be configured to determine the opening of one or more valves, based on measured conditions of the fluid processing system 300A. The control of the architecture relating to this disclosure will be described in more detail with reference to Figures 4A-4B.

[0081] PX310 can be a rotary pressure exchanger. In some embodiments, PX310 is an isobaric or substantially isobaric pressure exchanger. PX310 may be configured to exchange pressure between a first fluid and a second fluid. PX310 may be configured to exchange pressure between a high-pressure first fluid (e.g., provided to PX310 at a high-pressure inlet, HP-IN) and a low-pressure second fluid (e.g., provided to PX310 at a low-pressure inlet, LP-IN). PX310 may reduce the pressure of the first fluid (e.g., to output from PX310 at a low-pressure outlet, LP-OUT) and increase the pressure of the second fluid (e.g., to output at a high-pressure outlet, HP-OUT). In some embodiments, PX310 is coupled to a motor (e.g., the rotation of the rotor of PX310 is controlled and / or regulated by the motor). In some embodiments, the mass flow rate through PX310 (e.g., mass flow rate of the first fluid, mass flow rate of the second fluid, etc.) may be related to the operating speed of PX310 (e.g., rotational speed of the rotor of a rotary PX). In some embodiments, the pressure of the fluids (e.g., first fluid, second fluid, etc.) in various components of the fluid processing system (e.g., fluid processing systems 300A-300C) may be related to the operating speed of PX310.

[0082] In some embodiments, the PX310 is configured to receive a high-pressure first fluid (e.g., HPin fluid 130 in Figures 1A-1B) via a high-pressure inlet. In some embodiments, the PX310 is configured to receive a low-pressure second fluid (e.g., LPin fluid 120 in Figures 1A-1B) via a low-pressure inlet. Although there is a reference to “high pressure” and “low pressure,” “high pressure” and “low pressure” are relative to each other and may not mean specific pressure values ​​(e.g., the pressure of HPin fluid 130 is higher than the pressure of LPin fluid 120). The PX310 can exchange pressure between the first and second fluids. The PX310 may provide the first fluid via a low-pressure outlet (e.g., LPout fluid 140) and the second fluid via a high-pressure outlet (e.g., HPout fluid 150). In some embodiments, the first fluid provided via the low-pressure outlet is low pressure, and the second fluid provided via the high-pressure outlet is high pressure. The PX310 can function as a high-pressure expansion valve, so that, for example, a fluid flowing through it (e.g., a fluid flowing from a high-pressure inlet to a low-pressure outlet) can expand. The PX310 can transfer pressure from one fluid flow to another, increasing the pressure in one of the fluid flows. The PX310 can function as both an isentropic (or substantially isentropic) expansion device and a compressor, thereby generating heat transfer, facilitating one or more operations in a refrigeration cycle, or performing similar actions. The compression process of the PX310 can be substantially isenthalpic.

[0083] In some embodiments, the first fluid may be a supercritical refrigerant fluid (e.g., supercritical CO2). In some embodiments, the first fluid may be a liquid refrigerant fluid (e.g., liquid CO2). In some embodiments, the second fluid may be a gaseous refrigerant fluid (e.g., gaseous CO2). In some embodiments, the second fluid may be a two-phase mixture refrigerant fluid (e.g., a liquid-gas mixture of CO2). In some embodiments, the second fluid may be a liquid refrigerant fluid (e.g., liquid CO2).

[0084] In some embodiments, the fluid processing system 300A includes a main gas cooler 329 (e.g., a condenser), an evaporator 318, and a main compressor 322. In some embodiments, the fluid processing system 300A may include an auxiliary gas cooler, which may be coupled, for example, between the HP-OUT and the receiver 313. In some embodiments, the main gas cooler 329 and / or the auxiliary gas cooler may or may not function as a condenser, and for example, the fluid processing system may be operated at a pressure and temperature such that the fluid condenses in the gas cooler, or at a pressure and temperature such that it does not condense. Any embodiment described herein may include a gas cooler that may or may not function as a condenser in one or more applications. In some embodiments, for example, above the critical point of the fluid, the thermodynamic distinction between gas and liquid in the fluid disappears, and the fluid (e.g., the fluid in the condenser) can exist in a supercritical state (for example, both the input and output fluids of the condenser may be supercritical, one or both of the input and output fluids of the condenser may be supercritical, or neither fluid may be supercritical). In some embodiments, the fluid processing system 300A is a refrigeration system. For example, the evaporator 318 and / or the second evaporator 319 can facilitate the absorption of heat by the fluid processing system 300A from a heat source (e.g., a refrigerated area, a low-temperature reservoir, etc.) into the refrigerated fluid. This heat can be released to a heat sink (e.g., the environment, a high-temperature reservoir, etc.) via the main gas cooler 329 and / or the auxiliary gas cooler. In some embodiments, the refrigerated fluid facilitates heat transfer from the environment associated with the evaporator 318 to the environment associated with the main gas cooler 329. The main compressor 322 of the fluid processing system 300A can increase the corresponding pressure of the refrigerating fluid along the flow path between the evaporator 318 and the main gas cooler 329. In some embodiments, the refrigerating fluid is CO2 or another refrigerating fluid. The refrigerating fluid can flow in a substantially cyclic manner (e.g., from the main gas cooler 329 to PX310, then to the evaporator 318, then to the main compressor 322, and then to the main gas cooler 329, etc.).

[0085] In some embodiments, the fluid processing system 300A is a heat pump system. For example, heat can be released by the fluid in the main gas cooler 329 to a region to be heated (for example, to heat the interior space of a building). Heat can be absorbed from the environment by the fluid of the fluid processing system 300A in the evaporator 318 in order to transfer heat to the environment of the main gas cooler 329. In some embodiments, the fluid processing system 300A may be a reversible heat pump.

[0086] In some embodiments, the main compressor 322 increases the fluid pressure beyond a threshold amount (for example, the main compressor 322 may operate over a pressure difference greater than the threshold amount, or similar). For example, the main compressor 322 may increase the fluid pressure by any range including about 100–1200 PSI, about 500–1100 PSI, about 800–1000 PSI, about 900 PSI, at least 100 PSI, at least 500 PSI, etc. In some embodiments, the operation of the main compressor 322 may be performed by multiple physical devices, such as multiple compressors, multiple pumps, or similar. The multiple compressors performing the operation of the main compressor 322 may be arranged in parallel, in series, or a combination of these arrangements. Any description relating to the main compressor 322 can be generalized to include multiple devices, for example, by summing the energy consumed, or by calculating the total flow rate of fluid through the compressor system, taking into account the arrangement, specifications, and operating speed of each compressor in the compressor system.

[0087] A motor or other speed control device may be configured to regulate the operation of PX310 (for example, by adjusting the operating speed of the motor). The regulation of the operating speed of PX310 may be performed in response to receiving a control signal from the controller. Control of PX310 may be based on the fluid pressure of the main gas cooler 329. Control of PX310 may also be based on additional indicators such as ambient temperature, fluid temperature, target evaporator temperature, and operating efficiency of the fluid processing system 300A. The controller may generate a control signal aimed at achieving and / or maintaining a target pressure of the main gas cooler 329. The target pressure of the main gas cooler 329 may be modified by the ambient temperature (e.g., the heat sink temperature for released heat), and may be modified to achieve, for example, optimal energy efficiency, heat transfer, refrigeration, etc. For example, increasing the operating speed of PX310 may increase the flow rate of fluid through PX310. Increasing the operating speed of PX310 may decrease the fluid pressure of the main gas cooler 329.

[0088] In some embodiments, the target pressure of the main gas cooler 329 may be selected to maximize the system's energy efficiency, for example, to maximize the heat transfer between the main gas cooler 329 and the environment, to maximize the system's energy efficiency, or to maximize the coefficient of performance (COP, e.g., the ratio of heat transferred by the system to power consumed by the system's pumps / compressors).

[0089] In some embodiments, a device for adjusting the speed of the PX may act to operate, activate, or accelerate the PX310. For example, a motor may drive the PX310. The motor may draw power from a power source to drive the PX310. In some embodiments, the motor may act like a generator. For example, the PX310 may be driven by the fluid of the fluid processing system 300A (e.g., driven by a pressure difference in the fluid, and driven by one or more pumps and / or compressors of the system). The motor may provide additional resistance to the operation of the PX310 (e.g., resistance to the rotation of the rotor of a rotary PX), thereby reducing the operating speed of the PX310. The motor may generate power (e.g., convert the rotational energy of the PX310 into electrical energy).

[0090] In some embodiments, the evaporator 318 (and / or the second evaporator 319) is a heat exchanger that provides corresponding thermal energy from the environment (e.g., the medium of the environment) to the fluid of the fluid processing system 300A. For example, the evaporator 318 may receive heat (e.g., thermal energy) from the air of the environment and provide that heat to the fluid. In some embodiments, the environment is a refrigerated space such as the inside of a refrigerator or freezer, an interior space (e.g., the interior space of a building or vehicle), or any other space that should be kept in a cooled state. For example, the environment may be the inside of a freezer or refrigerated compartment in a supermarket or warehouse. In some embodiments, the evaporator 318 may absorb heat from the environment to be provided to the main gas cooler 329, and for example, heating the area around the main gas cooler 329 may be a target result of the fluid processing system 300A. In some embodiments, the evaporator 318 and the second evaporator 319 may be associated with different target applications, different environments, different target temperatures, or similar. For example, the evaporator 318 may be associated with one or more refrigerated compartments in a supermarket, while the second evaporator 319 may be associated with one or more freezers in the same supermarket.

[0091] In some embodiments, the fluid handling system 300A may include a secondary evaporator. The fluid handling system 300A may further include secondary components corresponding to any component of the evaporator 318, such as input and output lines, valves, gauges, controllers, etc. In some embodiments, a second evaporator 319 receives a portion of the fluid flow directed to the evaporator 318. For example, the secondary evaporator may receive a portion of the flow from the low-pressure outlet of PX310, for example, via a receiver 313. In some embodiments, the secondary evaporator may target a different temperature than the evaporator 318 (for example, the evaporators may be associated with a refrigeration system having different target temperatures, such as a refrigerator and a freezer). In some embodiments, the two evaporators (e.g., evaporator 318 and the secondary evaporator) may operate at different fluid pressures. The fluid output from one or more secondary evaporators may be directed to one or more components (e.g., valves, expansion valves, pumps, compressors, or similar devices, e.g., a cryogenic compressor 323) to modify the pressure of the output fluid so that the pressures are substantially similar when the output flows from the two evaporators are combined.

[0092] In some embodiments, the main gas cooler 329 and / or auxiliary gas coolers are heat exchangers for transferring thermal energy from the fluid of the fluid processing system 300A to other environments. For example, the main gas cooler 329 may release heat (e.g., thermal energy) to the air of the external (e.g., outdoor) environment. In some embodiments, the main gas cooler 329 exchanges thermal energy (e.g., releases heat) to the outdoor space. For example, the main gas cooler 329 may be located outside a supermarket or warehouse building (e.g., on the roof of the building) and release heat to the outdoor environment. In other examples, the main gas cooler 329 may be located underground to facilitate the transfer of thermal energy between the fluid and the ground. In some embodiments, the main gas cooler 329 releases heat to the internal space while the evaporator 318 absorbs heat from the external space (e.g., in a heat pump configuration that provides heating to the internal space). The thermal energy released from the main gas cooler 329 can be used to heat an enclosed space (e.g., a substantially enclosed space).

[0093] In some embodiments, the fluid handling system 300A may include an auxiliary gas cooler. In some embodiments, the auxiliary gas cooler receives a second fluid from the high-pressure outlet of PX310, and the main gas cooler 329 receives output from the main compressor 322. In some embodiments, the auxiliary gas cooler is a heat exchanger that exchanges thermal energy (e.g., heat) between the second fluid and the environmental medium. In some embodiments, the auxiliary gas cooler exchanges thermal energy between the second fluid and the environment in which the main gas cooler 329 exchanges thermal energy, for example, the same environment as the exterior space of a building. In other embodiments, the auxiliary condenser exchanges thermal energy between the second fluid and an environment different from the environment in which the main gas cooler 329 exchanges thermal energy. In some embodiments, the auxiliary gas cooler operates at a different temperature than the main gas cooler 329. In some embodiments, the auxiliary gas cooler may operate at a different pressure than the main gas cooler 329. For example, the auxiliary gas cooler may operate at a lower pressure than the main gas cooler 329. The auxiliary gas cooler may operate at a target pressure different from the target pressure of the main gas cooler 329, or at a target pressure difference relative to the main gas cooler 329, etc. The auxiliary gas cooler may operate at a pressure about 20 PSI lower than the main gas cooler 329. The auxiliary gas cooler may operate at a pressure 15 to 30 PSI lower than the pressure of the main gas cooler 329. In some embodiments, the main gas cooler and the auxiliary gas cooler may be provided by the same device, for example, by a gas cooler having multiple fluid channels accommodating multiple fluid flows. In some embodiments, the main gas cooler and / or the auxiliary gas cooler may be associated with a device for regulating the heat exchanged with the fluid in the gas cooler. For example, the main gas cooler 329 and / or the auxiliary gas cooler may include, or be associated with, a fan to increase the airflow near the gas cooler, to increase heat transfer from the gas cooler, etc.

[0094] The fluid handling system 300A further includes a flash gas valve 320. The fluid handling system 300A may include a flash gas valve 320 for regulating the flow of gas on a flash gas bypass channel. In some embodiments, the flash gas valve 320 is a bypass valve that regulates the flow of gas from the gas outlet of the receiver 313 (e.g., a flash tank) to match the output of the evaporator 318. In some embodiments, the flow of gas from the receiver 313 flows along the flash gas bypass channel to bypass the evaporator 318. In some embodiments, the flash gas channel is located between the receiver 313 and a downstream position of the outlet of the evaporator 318. The gas flowing along the flash gas bypass channel can be matched with the output of the evaporator 318. The flash gas valve 320 may cause the gas collected in the receiver 313 to expand (e.g., to decrease in pressure) as the gas flows toward the main compressor 322. In some embodiments, the flash gas valve 320 may be an adjustable valve. In some embodiments, the flash gas valve 320 is activated by a controller based on sensor data.

[0095] The fluid processing system 300A may include an expansion valve 316 associated with the evaporator 318 and a secondary expansion valve 317 associated with a second evaporator 319. In some embodiments, the expansion valve 316 is positioned along the flow path between the receiver 313 and the evaporator 318, and is coupled, for example, between the receiver 313 and the evaporator 318. The expansion valve 316 may be an adjustable valve (e.g., an electronic expansion valve, a thermostat expansion valve, a ball valve, a gate valve, a poppet valve, etc.). The expansion valve 316 may be controllable by a user (e.g., a technician, operator, engineer, etc.) or a controller. In some embodiments, the expansion valve 316 is actuated by a controller based on sensor data (e.g., pressure sensor data, flow sensor data, temperature sensor data, etc.). In some embodiments, the expansion valve 316 is a thermal expansion valve. The expansion valve 316 may be operated (e.g., opened or closed) based on temperature data associated with the evaporator 318 (e.g., the temperature of the liquid in the evaporator, the temperature of the gas in the evaporator, the temperature of the fluid flowing into the evaporator, the temperature of the fluid flowing out of the evaporator, etc.). For example, a pressure-sensitive component of the expansion valve 316 (e.g., a sensing bulb) may increase or decrease the pressure applied to the diaphragm of the expansion valve 316, thereby opening or closing a poppet valve coupled to the diaphragm, which in turn causes a greater or lesser fluid flow into the evaporator 318 and a greater or lesser fluid expansion. The pressure-sensitive component of the expansion valve may be located near the downstream end of the evaporator 318 (e.g., near the outlet of the evaporator 318, outside the evaporator 318, inside the evaporator 318, or a similar location) and may be in fluid communication with the diaphragm via a fluid line (e.g., a sensing capillary). In some embodiments, the expansion valve 316 is controlled and actuated entirely on the basis of electronic commands (e.g., from a controller). The secondary expansion valve 317 may share one or more features with the expansion valve 316, including features relating to the relationship between the expansion valve 316 and the evaporator 318 that are shared with the second evaporator 319.

[0096] The fluid processing system 300A includes a subcooler 315. The subcooler 315 may be a heat exchanger configured to exchange heat between different portions of the fluid output by the main gas cooler 329. The subcooler 315 may include a main or primary fluid channel coupled to the main cooling flow of the working fluid. The subcooler 315 may include a secondary or cooling fluid channel coupled to a fluid flow that absorbs heat from the main flow within the subcooler 315. The subcooling valve 312 may be a control valve and may be opened to a target opening, for example, to allow a target flow rate through the secondary channel of the subcooler 315. The subcooling valve 312 may function as an expansion valve and may be such that the temperature of the fluid supplied to the subcooling valve 312 is higher than the temperature of the fluid supplied by the subcooling valve 312 to the secondary channel of the subcooler 315. PX310 can enable this additional cooling step without efficiency losses due to the additional pump power required to increase the pressure of the secondary cooling fluid by providing compression of the fluid from the main channel of the supercooler 315 by exchanging the fluid and pressure with that fluid. The main body can be supplied to the high-pressure inlet of PX310 by the supercooler 315. The secondary cooling fluid can be supplied to the low-pressure inlet of PX310 by the supercooler 315.

[0097] The fluid handling system 300A further includes a superheater 311. The superheater 311 may be a heat exchanger and may be configured to exchange heat between the fluid in the primary channel (e.g., the fluid flowing out from the HP-OUT) and the fluid in the secondary channel (e.g., the fluid that has passed through the evaporator but not yet through the main compressor 322). The fluid flowing out from the HP-OUT may be a high-pressure, high-temperature fluid. Heat may be exchanged to lower the temperature of the fluid supplied by the HP-OUT and to raise the temperature of the fluid supplied to the main compressor 322 (or, in some embodiments, the cryogenic compressor 323). The superheater 311 may provide several advantages to the fluid handling system 300A. The superheater 311 may provide a temperature rise for the working fluid supplied to the main compressor 322. In some cases, a compressor such as the compressor 322 may be configured to take single-phase fluids, for example, to take only gases. If a different phase (e.g., liquid) is supplied to the compressor 322, damage to the compressor 322 and other inefficiencies in the fluid handling system 300A may occur. By increasing the temperature of the fluid supplied to the main compressor 322, the risk of liquid being supplied to the main compressor 322 can be reduced and components of the fluid handling system 300A can be protected. The superheater 311 is one or more components that may be included in other systems to protect the compressor, for example, by allowing the removal of a hot gas bypass or a dump valve.

[0098] The superheater 311 may further provide improved efficiency by, for example, cooling the liquid output by the HP-OUT. The receiver 313 may receive the working fluid of the mixed phase, for example, both liquid and gaseous. Any gas contained in the receiver 313 will increase the load on the main compressor 322 without providing any usefulness in the evaporator of the fluid processing system 300A. The liquid in the receiver 313 may be used to perform refrigeration (or other heat transfer) operations in the evaporator. Increasing the proportion of liquid in the receiver 313 may improve system efficiency by reducing the generation of flash gas that cannot be used for system operation until it is compressed. The liquid portion of the fluid in the receiver 313 may be increased by releasing heat from the fluid supplied by the HP-OUT through the superheater 311 before the fluid is supplied to the receiver 313, thereby improving system efficiency.

[0099] The superheater 311 may be positioned in front of the main compressor 322 along the fluid flow. In other embodiments, the superheater 311 may be positioned in different locations, for example, along the flash gas outlet from the receiver 313 (e.g., alternative position 396), coupled after the medium-temperature evaporator (e.g., alternative position 397 located after the evaporator 318), coupled after the low-temperature evaporator (e.g., alternative position 398 located after the second evaporator 319), or positioned before the secondary or low-temperature compressor 323, and so on.

[0100] The introduction of the superheater 311 and the subcooler 315 can provide additional stability to the fluid processing system 300A. For example, the superheater 311 and the subcooler 315 can enable stable operation of the fluid processing system 300A at various ambient temperatures (e.g., temperatures near the main gas cooler 329). In particular, the introduction of these components can enable stable operation of the fluid processing system 300A at high ambient temperatures and / or improve the overall efficiency of the system.

[0101] In some embodiments, the introduction of a superheater 311 can be used to adjust the characteristics of the fluid supplied to the main compressor 322 (and / or the cryogenic compressor 323, depending on the location of the superheater). The temperature of the intake flow to the main compressor 322 can be increased. The pressure of the intake flow to the main compressor 322 can be increased.

[0102] The suction superheating of the main compressor 322 may be passively controlled, for example, by controlling the auxiliary high-pressure valve 369 based on other factors, and the superheating applied to the suction fluid of the main compressor 322 being based on the operation of the auxiliary high-pressure valve 369. The suction superheating of the main compressor 322 may also be actively controlled, for example, by active control using a hot gas bypass that returns the hot compressor outlet fluid to the suction side, although this may reduce system efficiency.

[0103] The fluid processing system 300A further includes an auxiliary high-pressure valve 369. The auxiliary high-pressure valve 369 may be a control valve and may, for example, enable a target fluid flow rate through the auxiliary high-pressure valve 369. The auxiliary high-pressure valve 369 may be an auxiliary control valve. The auxiliary high-pressure valve 369 may be coupled between the high-pressure outlet of PX310 and the inlet of receiver 313 and may, for example, be coupled either before or after the superheater 311 with respect to the fluid flow path. The auxiliary high-pressure valve 369 may, alternatively or additionally, be located on a flow path that includes an auxiliary gas cooler. The auxiliary high-pressure valve 369 may be controlled based on sensor data of the fluid processing system 300A, for example, as shown in Figure 4A.

[0104] The fluid handling system 300A includes a parallel valve 348. The parallel valve 348 may be a high-pressure valve (for example, it may be supplied with the same working fluid as that supplied to the HP-IN). The parallel valve 348 may be used to bypass the PX310, for example, under conditions where the use of the PX310 is inefficient, or where the operating volume of the PX310 is insufficient to achieve the target conditions. The fluid handling system 300A may provide control over the parallel valve 348, for example, based on the operating speed of the PX310, the pressure of the main gas cooler 329, etc.

[0105] In this specification, the terms “first fluid” and “second fluid” are used. In some embodiments, the first fluid and the second fluid are the same type of fluid (for example, a refrigeration fluid flowing within a fluid processing system). The “first fluid” may refer to the fluid flowing through PX310 from the high-pressure inlet to the low-pressure outlet, and / or the fluid flowing to or from the high-pressure inlet and / or low-pressure outlet of PX310. The “second fluid” may refer to the fluid flowing through PX310 from the low-pressure inlet to the high-pressure outlet, and / or the fluid flowing to or from the low-pressure inlet and / or high-pressure outlet of PX310.

[0106] In some embodiments, the fluid processing system 300A is a heat pump system capable of heating and cooling an environment (e.g., an indoor space). In some examples, either the main gas cooler 329 or the evaporator 318 is an outdoor unit, and the other is an indoor unit. In some examples, the main gas cooler 329 is an outdoor unit (e.g., a condensing unit), and the evaporator 318 is an indoor unit (e.g., located in a refrigerated space for storing food, pharmaceuticals, sensitive chemicals or materials, etc.). The fluid flow through the main gas cooler 329 and the evaporator 318 may be reversible (e.g., via a reversing valve coupled to the main compressor 322). The reversing valve may be switchable between directing the fluid flow out of the main compressor 322 towards the inlet of the main gas cooler 329 (e.g., an outdoor unit) or towards the inlet of the evaporator 318 (e.g., an indoor unit). In some embodiments, one or more valves and piping may be used to reverse the fluid flow through the main gas cooler 329 and evaporator 318, while directing the fluid flow through all components (e.g., one or more PX310s, main compressors 322, and / or similar) in the same direction.

[0107] In some embodiments, the system described herein is a heat pump system capable of heating an environment (e.g., an indoor space). In such a heat pump system, the main gas cooler 329 is located indoors, and the evaporator 318 is located outdoors. In the heat pump system, the evaporator absorbs heat from the surroundings, vaporizes a two-phase refrigerant fluid flowing through the evaporator, and then sends it to the compressor inlet. In some embodiments, a reversing valve may be used to switch from a refrigeration or air cooling system to a heat pump system, thereby allowing the fluid flow out of the main compressor 322 to be switched between being directed to the inlet of an outdoor unit or to the inlet of an indoor unit. In some embodiments, one or more valves and piping may be used to switch the fluid flow from the indoor unit to the outdoor unit while ensuring that the fluid flow through all components (e.g., PX310, main compressor 322, and / or similar) is directed in the same direction.

[0108] In some embodiments, the systems described herein (for example, one or more systems in Figures 3A-3C) may be used to heat an internal space and / or a confined space, to cool an internal space and / or a confined space, and / or to selectively (e.g., in a reversible) heat and / or cool a space.

[0109] Figure 3B is a schematic diagram of a fluid handling system 300B, including a pressure exchanger (PX310) and a low-pressure valve 326, according to several embodiments. In some embodiments, features having reference numerals corresponding to reference numerals in other drawings include similar characteristics, structures, and / or functions to those described in other drawings. In some embodiments, optional components described in relation to Figure 3A (e.g., a secondary evaporator, a compressor system as an alternative to the main compressor 322, etc.) may also be optional components of the fluid handling system 300B. In some examples, the features of the fluid handling system 300B have similar characteristics, structures, and / or functions to the fluid handling system 300A in Figure 3A.

[0110] The fluid processing system 300B may be configured to provide heat transfer (e.g., refrigeration) through the circulation of a working fluid (e.g., CO2). The fluid processing system 300B may be configured to perform actions to adjust one or more components of the fluid processing system 300B based on sensor data generated by sensors of the fluid processing system 300B. In some embodiments, the fluid processing system 300B may perform actions to achieve and / or maintain a target temperature in a target environment, such as the environment near the evaporator 318 and / or the second evaporator 319. The fluid processing system 300B may achieve a target temperature (e.g., food refrigeration temperature, first target refrigeration temperature) near the evaporator 318 and a second target temperature (e.g., freezer temperature, second target refrigeration temperature) near the second evaporator 319.

[0111] In some embodiments, the fluid processing system 300B may receive data indicating conditions for the fluid processing system 300B, which may include conditions for the working fluid, ambient conditions, conditions near the evaporator and / or gas cooler, etc. Fluid conditions may include temperature, pressure, mass flow rate, density, liquid level in the receiver, etc. The fluid processing system 300B may receive temperature data and / or other condition data from one or more sensors indicating the fluid conditions for the fluid processing system 300B. Based on the temperature data, the fluid processing system 300B may actuate one or more valves (e.g., parallel valve 348). The fluid processing system 300B may adjust one or more components to achieve and / or maintain a target fluid temperature, target fluid subcooling, or similar.

[0112] The fluid handling system 300B may include a parallel valve 348. The parallel valve 348 may be an expansion valve or a flow control valve. In some embodiments, the parallel valve 348 selectively adjusts the flow of fluid from the outlet of the main gas cooler 329 (e.g., the fluid discharged by the main gas cooler 329) to the receiver 313, for example, in parallel with PX310. In some embodiments, the parallel valve 348 may be operated to selectively adjust the fluid flow. The parallel valve 348 may selectively provide a portion of the fluid output by the main gas cooler 329 to the receiver 313. For example, the parallel valve 348 may be operated to open further to allow more fluid to flow from the main gas cooler 329 to the receiver 313, or the parallel valve 348 may be operated to close further to allow less fluid to flow from the main gas cooler 329 to the receiver 313. The fluid may expand as it flows through the parallel valve 348, which may cause a decrease in the fluid's pressure and / or temperature.

[0113] In some embodiments, the main gas cooler 329 may function as a condenser. In some embodiments, the fluid handling system may operate at a pressure and temperature at which the fluid condenses within the main gas cooler 329, or at a pressure and temperature at which it does not condense. Any embodiment described herein may include a condenser that can function as a gas cooler in one or more applications.

[0114] The fluid handling system 300B may include a receiver 313 (e.g., a flash tank). In some embodiments, the receiver 313 is a receiver configured to receive a flow of fluid (e.g., a first fluid) output from the low-pressure outlet of the PX 310. The receiver 313 may form a chamber for collecting the first fluid from the first outlet of the PX 310. The receiver 313 may receive the first fluid in a two-phase state (e.g., liquid and gas), a transcritical fluid, a supercritical fluid, a subcritical fluid, and / or a combination thereof. The receiver 313 may further receive a fluid flow from an auxiliary gas cooler 327, for example, via an auxiliary high-pressure valve 369. In some embodiments, the receiver 313 (e.g., a flash tank) is a tank made of welded sheet metal. The receiver 313 may include one or more flash tank inlets for receiving fluid and one or more flash tank outlets (e.g., a gas outlet and a liquid outlet) for discharging fluid. The first fluid (which is at low pressure) can separate into gas and liquid inside the receiver 313 (for example, as indicated by the liquid level shown in Figure 3B). The liquid of the first fluid can settle at the bottom of the receiver 313, while the gas of the first fluid can rise to the top of the receiver 313. The liquid can flow from the receiver 313 toward the evaporator 318 (for example, via the expansion valve 316). The liquid can also flow from the receiver 313 toward the second evaporator 319, for example, via the secondary expansion valve 317. The chamber of the receiver 313 can be maintained at a set pressure. This pressure can be set by the user (e.g., operator, technician, engineer, etc.) and / or a controller. In some embodiments, the pressure in the receiver 313 is controlled by one or more valves (e.g., expansion valve 316, flash gas valve 320, pressure regulating valve, safety valve, etc.). In some embodiments, the receiver 313 includes at least one pressure sensor (e.g., a pressure transducer). In some embodiments, the liquid level in the receiver 313 may be monitored (e.g., to prevent liquid from being delivered through the flush gas valve 320).

[0115] The fluid processing system 300B may include an expansion valve 316. The fluid processing system 300B may include a secondary expansion valve 317. In some embodiments, the expansion valve 316 is positioned along the flow path between the receiver 313 and the evaporator 318, for example, coupled between the receiver 313 and the evaporator 318. The secondary expansion valve 317 may be coupled between the receiver 313 and a second evaporator 319. The expansion valve 316 may be an adjustable valve (e.g., an electronic expansion valve, a thermostat expansion valve, a ball valve, a gate valve, a poppet valve, etc.). The expansion valve 316 may be controllable by a user (e.g., a technician, operator, engineer, etc.) or a controller. In some embodiments, the expansion valve 316 is actuated by a controller based on sensor data (e.g., pressure sensor data, flow sensor data, temperature sensor data, etc.). In some embodiments, the expansion valve 316 is a thermal expansion valve. The expansion valve 316 can be operated (e.g., opened or closed) based on temperature data associated with the evaporator 318 (e.g., the temperature of the liquid in the evaporator, the temperature of the gas in the evaporator, the temperature of the fluid flowing into the evaporator, the temperature of the fluid flowing out of the evaporator, etc.). For example, a pressure-sensitive component of the expansion valve 316 (e.g., a sensing valve) can increase or decrease the pressure applied to the diaphragm of the expansion valve 316, thereby opening or closing a poppet valve coupled to the diaphragm, which in turn causes a greater or lesser fluid flow into the evaporator 318 and a greater or lesser fluid expansion. The pressure-sensitive component of the expansion valve can be located near the downstream end of the evaporator 318 (e.g., near the outlet of the evaporator 318, outside the evaporator 318, inside the evaporator 318, etc.) and can be in fluid communication with the diaphragm via a fluid line (e.g., a sensing capillary). In some embodiments, the expansion valve 316 is controlled and operated entirely on an electronic basis. The operation and control of the secondary expansion valve 317 may be similar, for example, with respect to the fluid conditions of the second evaporator 319.

[0116] The fluid handling system 300B may include a flash gas valve 320 that regulates the flow of gas in a flash gas bypass channel. In some embodiments, the flash gas valve 320 is a bypass valve that regulates the flow of gas from the gas outlet of the receiver 313 to match the output of the evaporator 318. In some embodiments, the gas flow from the receiver 313 flows along the flash gas bypass channel to bypass the evaporator 318. In some embodiments, the flash gas channel is located between the receiver 313 and a downstream position of the outlet of the evaporator 318. The gas flowing along the flash gas bypass channel can be matched with the output of the evaporator 318. The flash gas valve 320 may cause the gas collected in the receiver 313 to expand (for example, to decrease in pressure) as the gas flows toward the main compressor 322. In some embodiments, the flash gas valve 320 may be an adjustable valve. In some embodiments, the flash gas valve 320 is actuated by a controller based on sensor data.

[0117] In some embodiments, the low-pressure outlet of PX310 may be connected to a receiver 313 via a low-pressure valve 326. The low-pressure valve 326 may be used to maintain a pressure difference between the low-pressure side of PX310 (e.g., the low-pressure subsystem) and the receiver 313. For example, the receiver 313 may be maintained at a lower pressure than the low-pressure subsystem of PX310, for example, 10 PSI lower, 20 PSI lower, 50 PSI lower, or 100 PSI lower. By increasing the pressure on the low-pressure side of PX310, the operation of PX310 may be improved (e.g., travel distance, efficiency, pressure exchange is improved, and energy loss is reduced). In some embodiments, the control of the low-pressure valve 326 may be performed based on sensor data, for example, sensor data related to the fluid pressure on the low-pressure side of PX310 and fluid pressure data in the receiver 313.

[0118] The fluid handling system 300B includes a low-pressure booster 314. The low-pressure booster may be a booster, pump, compressor, lift device, etc., for increasing the pressure of the fluid supplied to the LP-IN of PX310. In some embodiments, the need for a low-pressure booster (e.g., low-pressure booster 314) may be eliminated by other components, architecture, fluid flow paths, or similar. In some embodiments, the control of one or more components may be based on the operation of the low-pressure booster 314. For example, the fluid flow rate to the LP-IN may be calculated based on the operating speed of the low-pressure booster 314, which may be used to control other components (e.g., auxiliary high-pressure valve 369).

[0119] The fluid handling system 300B includes an auxiliary gas cooler 327. The auxiliary gas cooler 327 may provide some of the same advantages as the superheater 311 shown in Figure 3A, for example, the auxiliary gas cooler 327 may cool the fluid supplied by the HP-OUT, thereby increasing the proportion of liquid in the receiver 313 and improving the efficiency of the fluid handling system 300B. In some embodiments, the architecture including the low-pressure valve 326 may be combined alternatively or additionally with an architecture including a superheater 311 and / or an architecture including a superheater located in other positions (e.g., alternative positions 396, 397, 398, etc.). Furthermore, the architecture including the low-pressure valve 326 may be combined with a subcooler 315, a subcooling valve 312, etc.

[0120] Figure 3C is a schematic diagram of a fluid processing system 300C including a subcooler 315 and a superheater 311 according to several embodiments. Features having reference numerals corresponding to reference numerals in other drawings may include similar characteristics, structures, and / or functions as those described in other drawings. In some embodiments, optional components described in relation to Figures 3A-3B may also be optional components of the fluid processing system 300C. Features of the fluid processing system 300B may have similar characteristics, structures, and / or functions as those of the fluid processing systems 300A-300B.

[0121] The fluid processing system 300C may be configured to provide heat transfer (e.g., refrigeration) through the circulation of a working fluid (e.g., CO2 in one or more phases, such as a liquid, gas, or supercritical fluid). The fluid processing system 300C may be configured to perform actions to adjust one or more components of the fluid processing system 300C based on sensor data generated by sensors associated with the fluid processing system 300C. The fluid processing system 300C may perform actions to achieve and / or maintain a target temperature in one or more environments, such as inside a building or in a grocery store's freezer case. The fluid processing system 300C may perform actions to achieve and / or maintain target conditions of the fluid processing system, such as fluid temperature, pressure, density, and liquid level at various locations within the fluid processing system 300C. The fluid processing system 300C may adjust one or more components to achieve target conditions, for example, by acting a valve, adjusting the motor of PX310, adjusting the fan speed, and adjusting the compressor speed.

[0122] The fluid handling system 300C includes a parallel valve 348. The parallel valve 348 can, at least in part, determine the flow rate of the working fluid to the receiver 313. The parallel valve 348 can selectively supply a portion of the fluid output by the main gas cooler 329 to the receiver 313.

[0123] In some embodiments, the main gas cooler 329 may function as a condenser. In some embodiments, the fluid handling system may operate at a pressure and temperature at which the fluid condenses within the main gas cooler 329, or at a pressure and temperature at which it does not condense. Any embodiment described herein may include a condenser that can function as a gas cooler in one or more applications.

[0124] The fluid handling system 300C further includes a receiver 313. The receiver 313 can receive fluid from the low-pressure outlet of PX310 and from the superheater 311. The receiver 313 can supply fluid to the evaporator 318 to absorb heat from the environment near the evaporator 318 and / or supply fluid to the main compressor 322 via the flash gas valve 320. The receiver 313 can enable phase separation of the working fluid of the fluid handling system 300C.

[0125] Components such as the auxiliary high-pressure valve 369, the parallel valve 348, and the subcooler 315, and the operation of these components, may share one or more features with the corresponding components in Figure 3B. For example, the subcooler 315 may cool the liquid supplied to the HP-IN of the PX310 by exchanging heat with a portion of the fluid that expands through the subcooling valve 312. The subcooler 315 may receive a portion of the fluid into a secondary or cooling fluid channel to exchange heat with the fluid output by the main gas cooler 329. The secondary or cooling fluid channel of the subcooler 315 may receive fluid from the auxiliary gas cooler 327, which receives fluid from the high-pressure outlet of the PX310. In some embodiments, such as in the fluid handling system 300C lacking the subcooling valve 312 in Figure 3A, subcooling may not be controlled, and for example, there may be no control signals associated with monitoring and / or regulating the subcooling performed by the subcooler 315. In some embodiments, as shown in Figure 3C, a secondary or cooling channel may receive a portion of the fluid diverted from the primary flow after the primary flow has passed through the primary channel of the supercooler 315. A subcooling valve 312 may expand a portion of the fluid that has passed through the supercooler 315 to cool additional fluid supplied to the supercooler 315 from the main gas cooler 329. By acquiring the cooling fluid that has already passed through the supercooler 315 for the secondary channel of the supercooler 315, the operation of the supercooler 315 can be improved compared to other architectures. For example, the fluid passing through the supercooler 315 is cooled by heat exchange and then can be further cooled by expansion through the subcooling valve 312, which can result in the working fluid supplied to the HP-IN being at a lower temperature than would otherwise be achieved.

[0126] Further components of the fluid processing system 300C, such as PX310, main compressor 322, expansion valve 316, etc., may perform functions corresponding to those functions described in relation to the fluid processing systems 300A to 300B in Figures 3A to 3B.

[0127] An architecture including a superheater 311 (shown here in a different location than in Figure 3A, but any relevant location may be used) may also include a supercooler 315. An architecture including a superheater 311 may also include a low-pressure booster. An architecture including a supercooler may also include an auxiliary gas cooler. In some embodiments, an auxiliary gas cooler and a superheater may be used, for example, by the fluid flowing out from HP-OUT, some heat may be released through the superheater and additional fluid may be released in the auxiliary gas cooler. Any combination of these components may be included with a valve to maintain the pressure difference between the receiver 313 and the low-pressure side of PX310, as shown, for example, in Figure 3B.

[0128] Figure 4A is a schematic diagram of a fluid processing system 400A, which includes a PX410, an auxiliary gas cooler 427, and various controllers and other components for providing control of the fluid processing system 400A, according to several embodiments.

[0129] The fluid processing system 400A includes components for performing heat transfer operations. The fluid processing system 400A includes PX410, a main gas cooler 429, an auxiliary gas cooler 427, and an evaporator 418. The fluid processing system 400A further includes a receiver 413, a flash gas valve 420, and an expansion valve 416. The fluid processing system 400A further includes an auxiliary high-pressure valve 469, a main compressor 422, a low-pressure valve 426, and a bypass high-pressure valve 428. The components of the fluid processing system 400A may share one or more features with the corresponding components of the fluid processing systems 300A to 300C shown in Figures 3A to 3C.

[0130] The fluid processing system 400A may include one or more sensors. These sensors measure characteristic values ​​associated with the system. For example, one or more temperature sensors may measure the temperature of the fluid flowing, the ambient temperature, the temperatures of high-temperature and / or low-temperature sinks associated with the system, etc. One or more pressure gauges may measure the pressure of the fluid in the fluid processing system 400A. One or more flowmeters may measure the flow rate (e.g., mass flow rate) of the fluid through the fluid processing system 400A. The fluid processing system 400A may utilize flow rate data from the flowmeters to determine one or more operations, including the operation of one or more components of the fluid processing system, such as the auxiliary high-pressure valve 469. One or more densimeters (e.g., two-phase fluid densimeters, two-phase densimeters, Coriolis flowmeters, etc.) may measure the density of the fluid in the fluid processing system 400A. Other sensors (e.g., instruments) may measure additional characteristic values, such as the work performed by the various components, the heat flow through the system, the power consumed by the components of the system, the total fluid flow rate through the various parts of the system, etc. Figure 4A shows gauges 480, 481, and 482. In some embodiments, the illustration of gauges may indicate the inclusion of multiple instruments; for example, a gauge for determining volumetric flow rate may include a device for measuring mass flow rate and a device for measuring fluid density. In some cases, one or more sensors may be omitted for the sake of visual clarity in Figures 4A-4B.

[0131] The fluid processing system 400A includes controllers 490 and 491. The controllers of the fluid processing system 400A may be PID controllers. The controllers of the fluid processing system 400A may operate based on known relationships between sensor data and control outputs, for example, via lookup tables, functional forms of such relationships, or similar.

[0132] The control of the fluid processing system 400A may be performed by a computing device that executes commands to perform control tasks, for example, by a general-purpose computing device (desktop computer, laptop computer, tablet, smartphone, etc.). The control of the fluid processing system 400A may be performed by a specially constructed computing device. The control of the fluid processing system 400A may be performed by a control device such as a PID controller, a microcontroller, or other known method for providing control signals. The control of the fluid processing system 400A may include devices that perform multiple operations, for example, a single device that performs the operations of controllers 490 and 491, a single device that performs the operations of all controllers in the fluid processing system 400A, or any arrangement of the functions of various controllers performed by a combination of computing devices.

[0133] The controller 490 is operationally coupled to the auxiliary high-pressure valve 469. The controller 490 may receive one or more measurements from one or more gauges (e.g., sensors) of the fluid handling system 400A. Based on the one or more sensor measurements, the controller 490 may generate and / or provide one or more control signals to the auxiliary high-pressure valve 469. In the first example, the controller 490 may receive a fluid flow rate display and use the fluid flow rate display to determine the opening of the auxiliary high-pressure valve 469. The controller 490 may receive flow rate data from a flow meter and generate a control signal for the auxiliary high-pressure valve 469 based on the flow rate data. The fluid flow rate display may be based on a flow meter, for example, a flow meter that measures the flow rate of fluid to LP-IN or the flow rate of fluid from HP-OUT. In other examples, the operating speed of one or more pumps may be used to determine the fluid flow rate, for example, the operating speed of a low-pressure booster 414 may be used to determine the fluid flow rate and / or to generate a control signal that adjusts the operation of the auxiliary high-pressure valve 469 by the controller 490. Operating speed data for pumps, compressors, boosters, or similar devices may be used by the controller 490 to generate control signals for the auxiliary high-pressure valve 469. In conjunction with the operating speed of the low-pressure booster, further fluid characteristics may be used, such as the pressure of the fluid supplied to or output by the low-pressure booster 414, the temperature of the fluid supplied to or output by the low-pressure booster 414, or similar.

[0134] In some embodiments, an approach using sensors that can be easily and efficiently installed may be used. For example, PX410 can be added to an existing refrigeration system (e.g., a parent rack) to improve the performance of the existing system. It may be desirable to obtain data from easily accessible components or components installed with PX410, for example, to avoid expensive sensors (e.g., flow meters) and / or to avoid relying on sensors in the parent rack, which may be difficult to access and of uncertain quality. In some embodiments, controller 490 may obtain data indicating fluid characteristics in the HP-IN, for example, fluid characteristics at the outlet of the main gas cooler 429. Fluid characteristics may be obtained by gauge 480. In some embodiments, gauge 480 may be or include a temperature sensor, and controller 490 may generate a control signal for the auxiliary high-pressure valve 469 based on the temperature measured by gauge 480. In some embodiments, fluid temperature data associated with the working fluid at the outlet of the main gas cooler 429 may be used by controller 490 when determining or generating a control signal for the auxiliary high-pressure valve 429. In some embodiments, fluid properties can be derived based on ambient conditions, for example, conditions in the vicinity of the main gas cooler 429. For example, assumptions and / or calculations may be used to determine that the fluid temperature of the working fluid leaving the main gas cooler 429 is the same as the ambient temperature, or that it is a function of the ambient temperature (e.g., a few degrees higher than the ambient temperature), etc. Such measurements (e.g., via gauge 480) may be used in combination with a subcooler in some embodiments.

[0135] In some embodiments, the controller 490 may further acquire data from the PX410. For example, the controller 490 may acquire operating speed data from the PX410. Information regarding the fluid characteristics provided to the HP-IN and the operating speed of the PX410 may be used when determining the fluid characteristics at the HP-OUT (for example, the fluid characteristics at the HP-OUT may be assumed to be a function of the HP-IN, for example, a pressure difference between the two may be assumed, which may vary depending on the conditions), and this may be used by the controller 490 when generating a control signal for the auxiliary high-pressure valve 469.

[0136] In some embodiments, the auxiliary gas cooler 427 may release heat to the same environment as the main gas cooler 429. An assumption may be made to correlate the characteristics of the working fluid output by the auxiliary gas cooler 427 (e.g., temperature) with the characteristics of the working fluid output by the main gas cooler 429 (e.g., measured by gauge 480). The characteristics of the fluid supplied to the auxiliary high-pressure valve 469 may be determined by the controller 490 based on, for example, gauge 480, PX410, etc. The characteristics of the fluid after the auxiliary high-pressure valve 469 (e.g., fluid pressure) may be further measured (e.g., by gauge 482), and this may also be incorporated by the controller 490 when generating a control signal for the operation of the auxiliary high-pressure valve 469.

[0137] The controller 491 may be operationally coupled to the low-pressure valve 426. The low-pressure valve 426 may be configured to maintain a target pressure difference (e.g., 10 PSI, 20 PSI, 40 PSI, 50 PSI, 100 PSI, or any other arbitrary target pressure difference) between the low-pressure side of the PX410 (e.g., LP-OUT) and the receiver 413. The controller 491 may acquire pressure measurements that indicate the fluid characteristics of the low-pressure side of the PX410 and the fluid characteristics of the receiver 413. The controller 491 may generate a control signal based on the pressure measurements and provide that control signal to the low-pressure valve 426 to maintain the target pressure difference between the low-pressure side of the PX410 and the receiver 413.

[0138] A fluid processing system (e.g., a refrigeration system) may include devices for performing the operation of any combination of the controllers described above. The fluid processing system may include devices for performing the operation of controller 490. The fluid processing system may include devices for performing the operation of controller 491. The fluid processing system may include sensors, gauges, or other instrumentation devices associated with any controller described herein. The fluid processing system may include devices for performing the operation of any one of these controllers, any two of these controllers (e.g., controllers 490 and 491), etc. The fluid processing system may include inputs to controller 490 in any combination, such as the flow meter input and compressor speed input, the inputs to the illustrated gauges 480 and PX410, etc. Any combination of these controllers may be included in a fluid processing system (e.g., a refrigeration system).

[0139] In some embodiments, a controller (e.g., a central controller, a system controller, which may be combined with one or more of the controllers 490-491) receives sensor data indicating the temperature of the refrigerated space (e.g., a low-temperature reservoir near the evaporator 418) and / or the temperature of the heated space (e.g., a high-temperature reservoir near the main gas cooler 429). The controller can control the auxiliary high-pressure valve 469, the low-pressure valve 426, etc., based on sensor data received from one or more sensors of the fluid processing system 400A (e.g., one or more fluid flow sensors, temperature sensors, pressure sensors, etc.). In some embodiments, one or more sensors (e.g., pressure sensors, flow sensors, temperature sensors, etc.) are located near the inlets and / or outlets of the various components of the fluid processing system 400A (e.g., near the fluids discharged from the various components). In some embodiments, one or more sensors are located inside the components of the fluid processing system 400A. In some embodiments, a pressure sensor may be located near the inlet of the main compressor 422, and an additional pressure sensor may be located near the outlet of the main compressor 422. In some embodiments, a temperature sensor may be located near the inlet of the evaporator 418, and another temperature sensor may be located near the outlet of the evaporator 418 (for example, to measure the temperature of the fluid discharged from the evaporator 418). In some embodiments, a temperature sensor may be located inside the main gas cooler 429 and / or the auxiliary gas cooler 427. In some embodiments, flow sensors may be located at each inlet and outlet of the PX410 to measure the flow rates of the first and second fluids into and out of the PX410.

[0140] In some embodiments, a controller (e.g., a central controller, a system controller, which may be combined with one or more controllers 490-491 and / or additional controllers) receives sensor data indicating the temperature of the refrigerated space (e.g., the low-temperature reservoir near the evaporator 418) and / or the temperature of the heated space (e.g., the high-temperature reservoir near the main gas cooler 429). The controller may control the auxiliary high-pressure valve 469, PX410, main compressor 422, low-pressure booster 414, low-pressure valve 426, or any other controllable component of the fluid processing system based on sensor data received from one or more sensors of the fluid processing system (e.g., one or more fluid flow sensors, temperature sensors, pressure sensors, etc.). In some embodiments, one or more sensors (e.g., pressure sensors, flow sensors, temperature sensors, etc.) are located near the inlets and / or outlets of the various components of the fluid processing system 400A (e.g., near the fluids discharged from the various components). In some embodiments, one or more sensors are located inside the components of the fluid processing system 400A. In some embodiments, a pressure sensor may be located near the inlet of the main compressor 422, and an additional pressure sensor may be located near the outlet of the main compressor 422. In some embodiments, a temperature sensor may be located near the inlet of the evaporator 418, and another temperature sensor may be located near the outlet of the evaporator 418 (for example, to measure the temperature of the fluid discharged from the evaporator 418). In some embodiments, temperature sensors may be located inside the main gas cooler 429 and / or auxiliary gas cooler 427. In some embodiments, flow sensors may be located at each inlet and outlet of the PX410 to measure the flow rates of the first and second fluids into and out of the PX410.

[0141] Figure 4B is a schematic diagram of a fluid processing system 400B including sensors and controllers according to several embodiments. The fluid processing system 400B includes components similar to those of the fluid processing system 300C in Figure 3C. Components of the fluid processing system 400B may share one or more features, functions, or characteristics of the corresponding components of the fluid processing system 300C. The fluid processing system 400B includes a plurality of sensors, for example, gauge 483, gauge 484. The sensors may share one or more features, functions, or characteristics with the sensors included in the fluid processing system 400A in Figure 4A. The fluid processing system 400B includes a plurality of controllers, such as controller 492. The controllers may include or share features and / or characteristics with the controllers included in the fluid processing system 400B, for example, the controller architecture, the potential grouping of controller functions by fewer computing devices, or similar. Some controllers are applicable to various architectures, and the controllers can be used together in any combination relating to the target fluid processing system architecture. For example, an architecture such as the fluid handling system 400B can benefit from a controller directed to a low-pressure control valve, such as the controller 491 in Figure 4A. Any number of controllers described herein may be included in the target architecture and may be implemented by any number of devices.

[0142] The fluid handling system 400B includes a main gas cooler 429, a PX 410, a subcooler 415, a subcooling valve 412, a superheater 411, a receiver 413, a flash gas valve 420, an expansion valve 416, a second expansion valve 417, an evaporator 418, a second evaporator 419, a cryogenic compressor 423, and a main compressor 422. These components may perform functions similar to those of the corresponding components of the fluid handling system 300A or 400A.

[0143] The fluid processing system 400B may include gauges 483 and 484. The gauges of the fluid processing system 400B may have similar characteristics to the gauges of the fluid processing system 400A. Each gauge of the fluid processing system 400B may include multiple sensors, instruments, or other devices for determining measurements related to the control of the fluid processing system 400B. The gauges may include one or more temperature sensors, pressure sensors, flow meters, densimeters, or similar devices.

[0144] The fluid handling system 400B includes a controller 492. The controller 492 may be used to provide control signals for regulating the operation of the auxiliary high-pressure valve 469. As described in relation to the fluid handling system 400A, the controller 492 may provide control signals to the auxiliary high-pressure valve 469 based on characteristic measurements of the working fluid, for example, the working fluid supplied to the HP-IN and / or the working fluid on either side of the auxiliary high-pressure valve 469. In some embodiments (for example, if the refrigeration system includes a superheater), assumptions regarding the relationship between the working fluid output by the main gas cooler 429 and the fluid supplied to the auxiliary high-pressure valve 469 may not be valid. A gauge 483 may be used to provide information regarding the fluid conditions at the outlet of the main gas cooler 429. In some embodiments, fluid temperature data associated with the working fluid at the inlet or suction side of the main compressor 422 may be used by the controller 492 when generating control signals for the auxiliary gas cooler 469. The temperature of the fluid output from the outlet of the superheater 411 may indicate the temperature of the fluid supplied to the auxiliary high-pressure valve 469, for example, they may be the same temperature, they may be related by an algebraic relationship, or similar. In some embodiments, gauge 483 may be coupled alternatively after the supercooler 415, for example adjacent to the HP-IN. Gauge 484 may provide a temperature measurement of the fluid supplied to the main compressor 422. The conditions of the fluid supplied to the main compressor 422 may indicate the characteristics of the fluid that has passed through the superheater 411, for example, the fluid temperatures of the two outlet flows of the superheater 411 may be equivalent, related, etc. In some embodiments (for example, when the superheater 411 is located in a different position), gauge 484 may instead measure the characteristics of the fluid at another location, for example, the characteristics of the fluid near the outlet of the channel of the superheater 411. In some embodiments, the gauge 484 may alternatively measure the fluid properties of the fluid supplied to the auxiliary high-pressure valve 469.

[0145] In some embodiments, the opening degree of the auxiliary high-pressure valve 469 may be based on the opening degree of the subcooling valve 412. For example, a function related to the target flow rate through the auxiliary high-pressure control valve may be used by the controller 492 to determine the opening degree of the auxiliary high-pressure valve 469, based on the characteristics of the auxiliary high-pressure control valve, the characteristics of the subcooling valve 412, and the opening degree of the subcooling valve 412. Operating data associated with the operation of bypass valves such as the subcooling valve 412 may be used by the controller 492 to determine the opening degree of the auxiliary high-pressure valve 469. Determining the opening degree of the auxiliary high-pressure valve 469 using the opening degree of the subcooling valve 412 may be particularly important when the fluid flow supplied to the valve may be related, for example, when assumed to be at the same temperature, when related by an algebraic equation, or similar. For example, a fluid handling system including an auxiliary gas cooler and a subcooling valve 412 may supply input fluid at approximately the same temperature to the valve, and an equation relating the predicted flows through these two valves may be used by the controller 492 when generating a control signal. In some cases, for example, if the subcooling valve 412 and the auxiliary high-pressure valve 469 are valves of the same model, a simple formula may be used, for example, if the opening of the auxiliary high-pressure valve 469 matches the opening of the subcooling valve 412, or if the opening of the auxiliary high-pressure valve 469 differs from the opening of the subcooling valve 412 by a few percent (for example, to account for inefficiencies in the fluid handling system), or a similar formula may be used. Generating a control signal may involve determining the target opening of the auxiliary high-pressure valve 469 by utilizing a function that relates the opening of the subcooling valve 412 to the opening of the auxiliary high-pressure valve 469, by referring to a lookup table, or similar means.

[0146] Figures 5A to 5B are flowcharts illustrating methods 500A to 500B for controlling a fluid processing system (for example, one or more of the fluid processing systems 300A to 300C in Figures 3A to 3C) according to several embodiments. In some embodiments, methods 500A to 500B are executed by processing logic including hardware (e.g., circuits, dedicated logic, programmable logic, microcode, processing units, etc.), software (e.g., commands run on processing units, processors such as central processing units or image processing units, general-purpose computer systems, or dedicated machines), firmware, microcode, or a combination thereof. In some embodiments, methods 500A to 500B are executed at least in part by one or more controllers. In some embodiments, a non-temporary storage medium stores commands that cause one or more processing units to execute methods 500A to 500B when executed by one or more processing units.

[0147] For the sake of brevity, methods 500A to 500B are presented and described as a series of operations. However, the operations relating to this disclosure may occur in various orders and / or simultaneously, and together with other operations not presented and described herein. Furthermore, in some embodiments, not all illustrated operations are performed to implement methods 500A to 500B in accordance with the subject matter of this disclosure. In addition, those skilled in the art will understand and recognize that methods 500A to 500B may alternatively be represented as a series of interrelated states via a state diagram or events.

[0148] Figure 5A is a flow diagram of method 500A for providing control of a fluid processing system according to several embodiments. In block 502, processing logic (e.g., processing unit, controller, computer processor, etc.) acquires a characteristic representation of the working fluid of the refrigeration system supplied to the inlet of the PX. The characteristics of the working fluid may include measurements from one or more flow meters (e.g., a flow meter coupled to LP-IN, a flow meter coupled to HP-OUT, or similar) configured to determine the mass flow rate of the working fluid supplied by the high-pressure outlet of the PX. The characteristics of the working fluid may include, for example, the operating speed of a pump that supplies the working fluid to the low-pressure inlet of the PX, such as a low-pressure booster. The characteristics of the working fluid may include measurements of the working fluid temperature at the outlet of the gas cooler of the refrigeration system, the working fluid temperature at the high-pressure inlet of the PX, or the working fluid temperature supplied to the compressor of the system, such as the main compressor or cryogenic compressor.

[0149] In block 504, the processing logic generates a first control signal based on a characteristic representation of the working fluid at the inlet of the PX. The generation of the first control signal may optionally be based on further inputs, such as the operating speed of the PX, the working fluid conditions in other parts of the refrigeration system, etc. For example, the working fluid conditions supplied to one or more compressors, the fluid conditions on both sides of an auxiliary high-pressure valve (e.g., a high-pressure control valve), or similar may be used when generating the control signal. In some embodiments, the high-pressure control valve may be configured to regulate the flow of working fluid through a first channel of a heat exchanger (e.g., a superheater). In some embodiments, the second channel of the heat exchanger may be coupled between one or more evaporators and one or more compressors, for example, between a cryogenic evaporator and a cryogenic compressor, between an evaporator and a main compressor, or similar locations. In some embodiments, the second channel of the heat exchanger may be coupled before a compressor, for example, between a flash gas valve and a main compressor. In some embodiments, the heat exchanger may be configured to transfer heat from a fluid in a first channel (e.g., a fluid supplied via HP-OUT) to a fluid in a second channel (e.g., a fluid supplied to a compressor in a refrigeration system).

[0150] In block 506, the processing logic provides a first control signal to a high-pressure control valve that is fluidly connected between the HP-OUT and the receiver. The fluid passage between the HP-OUT and the receiver may further include a heat exchanger, an auxiliary gas cooler, or similar. The high-pressure control valve may be configured to regulate its operation based on the first control signal.

[0151] In block 508, the processing logic optionally obtains a display of the pressure difference between the receiver and the low-pressure inlet of the PX. The low-pressure outlet pressure may be measured directly, based on the pressure at the low-pressure inlet of the PX, calculated based on the low-pressure booster speed and / or PX speed, etc. The receiver pressure may be provided by a pressure gauge associated with the receiver or by other pressure sensors.

[0152] In block 510, the processing logic optionally generates a second control signal based on the pressure difference. This second control signal may be based on comparing the pressure difference with a target pressure difference. The target pressure difference may be a single value or may vary based on conditions, such as ambient conditions, fluid conditions, evaporator conditions, heat exchanger conditions, or similar. The target pressure difference may be determined via one or more functions, lookup tables, or similar.

[0153] In block 512, the processing logic provides a second control signal to a second control valve, which is in fluid communication with the low-pressure outlet of the PX and the receiver. The second control valve may be configured to maintain a pressure difference between the low-pressure side of the PX and the receiver, for example, to maintain a higher pressure on the low-pressure side of the PX than in the receiver. The second control valve is configured to adjust its operation (e.g., opening degree (%)) based on the control signal.

[0154] Figure 5B is a flowchart of method 500B for providing control of a refrigeration system according to several embodiments. In block 520, the processing logic obtains a display of the pressure difference between the receiver of the refrigeration system and the low-pressure subsystem of the PX of the refrigeration system.

[0155] In block 522, the processing logic generates a first control signal based on the displayed pressure difference. Generating the first control signal optionally further includes comparing the pressure difference with a target pressure difference.

[0156] In block 524, the processing logic provides a first control signal to a control valve. The control valve is in fluid communication with the low-pressure outlet of the PX and the receiver. The control valve is configured to maintain a pressure difference between the low-pressure side of the PX and the receiver. The control valve is configured to adjust its operation (e.g., opening degree (%)) based on the first control signal.

[0157] In block 526, the processing logic optionally generates a second control signal. This second control signal may be based on an indication of the operating speed of the PX. This second control signal may be based on the temperature of a fluid, for example, the temperature of a fluid supplied to the high-pressure inlet of the PX, a fluid supplied to the compressor of a refrigeration system, or similar. The fluid supplied to the compressor may be supplied to the compressor from the outlet of a heat exchanger (e.g., a superheater). The fluid supplied to the compressor may be heated by exchanging heat in the heat exchanger with a fluid supplied to the heat exchanger from the HP-OUT of the PX.

[0158] In block 528, the processing logic provides a second control signal to a high-pressure control valve. The high-pressure control valve is configured to regulate the flow of working fluid between the high-pressure outlet of PX and the receiver. The high-pressure control valve is configured to adjust its operation based on the control signal.

[0159] Figure 6 is a block diagram showing a computer system 600 according to several embodiments. In some embodiments, the computer system 600 is a client device. In some embodiments, the computer system 600 is a controller device (e.g., a server, a control module, a centralized control system, controllers 490-492 in Figures 4A-4B, etc.).

[0160] In some embodiments, the computer system 600 is connected to other computer systems (for example, via a network such as a local area network (LAN), intranet, extranet, or the Internet). The computer system 600 operates as a server or client computer in a client-server environment, or as a peer computer in a peer-to-peer or distributed network environment. In some embodiments, the computer system 600 is provided by a personal computer (PC), tablet PC, set-top box (STB), personal digital assistant (PDA), mobile phone, web appliance, server, network router, switch or bridge, or any device capable of executing a set of instructions (whether periodic or not) that specify the actions to be performed by the device. Furthermore, the term “computer” also includes a collection of computers that individually or collectively execute one (or more) sets of instructions for performing one or more of the methods described herein.

[0161] In some embodiments, the computer system 600 includes a processing unit 602, volatile memory 604 (e.g., RAM (Random Access Memory)), non-volatile memory 606 (e.g., ROM (Read Only Memory) or EEPROM (Electrically-Erasable Programmable ROM)), and / or data storage device 616, which communicate with each other via a bus 608.

[0162] In some embodiments, the processing unit 602 is provided by one or more processors, such as a general-purpose processor (e.g., a CISC microprocessor, a RISC microprocessor, a VLIW microprocessor, a microprocessor implementing various command sets, or a microprocessor implementing a combination of command sets) or a specialized processor (e.g., an ASIC, FPGA, DSP, PID controller, or network processor). In some embodiments, the processing unit 602 is provided by one or more of the following: a single processor, multiple processors, a single processor having multiple processing cores, etc.

[0163] In some embodiments, the computer system 600 further includes a network interface device 622 (e.g., connected to network 674). In some embodiments, the computer system 600 includes one or more input / output (I / O) devices. In some embodiments, the computer system 600 further includes a video display device 610 (e.g., a liquid crystal display (LCD)), an alphanumeric input device 612 (e.g., a keyboard), a cursor control device 614 (e.g., a mouse), and / or a signal generator 620. The computer system 600 may include a signal input device 615, which is used, for example, to receive signals from other devices. For example, the signal input device 615 facilitates the computer system 600's reception of measurement data from sensors associated with the fluid processing system. The signal generator 620 may be used to generate and / or transmit control signals to send commands to one or more components of the fluid processing system. The signal generator 620 may transmit control signals to various high-pressure valves, booster pumps, cooling components, PX components, etc.

[0164] In some implementations, a data storage device 616 (e.g., disk drive storage, fixed and / or removable storage, fixed disk drive, removable memory card, optical storage, network-attached storage (NAS), and / or storage area network (SAN)) includes a non-temporary computer-readable storage medium 624 which stores a directive 626 that encodes one or more of the methods or functions described herein and implements the methods described herein. A control module 633 (e.g., including any of the controllers 490 to 492 in Figures 4A to 4B, performing the methods in Figures 5A to 5B, etc.) may include the directive 626.

[0165] In some embodiments, the instruction 626 is also present, fully or partially, in the volatile memory 604 and / or the processing unit 602 at the time of its execution. Thus, in some embodiments, the volatile memory 604 and the processing unit 602 also constitute a machine-readable storage medium.

[0166] Although the computer-readable storage medium 624 is shown as a single medium in the illustrated example, the term “computer-readable storage medium” includes single or multiple mediums (e.g., centralized or distributed databases and / or associated caches and servers) that store or encode one or more sets of executable instructions and cause a computer to execute one or more of the methods described herein. The term “computer-readable storage medium” also includes any tangible medium capable of storing or encoding a set of instructions executed by a computer. The term “computer-readable storage medium” is not limited to solid-state memory, optical media, and magnetic media.

[0167] The methods, components, and features described herein may be implemented by discrete hardware components or integrated into the functionality of other hardware components such as ASICs, FPGAs, DSPs, or similar devices. Furthermore, the methods, components, and features may be implemented by firmware modules or functional circuits within hardware devices. Moreover, the methods, components, and features may be implemented in any combination of hardware devices and computer program components, or in computer programs.

[0168] Unless otherwise specified or as is clear from the context, terms such as “operate,” “adjust,” “cause,” “control,” “determine,” “identify,” “provide,” “receive,” “generate,” and “obtain” refer to actions and processes performed or implemented by a computer system, which manipulate and convert data expressed as physical (electronic) quantities in the computer system’s registers and memory devices into other data similarly expressed as physical quantities in the computer system’s memory devices or registers, or other information memory devices, transmission units, or display devices. Furthermore, terms such as “first,” “second,” “third,” and “fourth” used herein are labels to distinguish different elements and do not necessarily have an ordinal meaning according to their numerical representation.

[0169] The examples described herein also relate to apparatus for performing the methods described herein. Such apparatus may be specifically configured for performing the methods described herein, or may include a general-purpose computer system selectively programmed by a computer program stored in the computer system. Such a computer program may be stored in a computer-readable tangible storage medium.

[0170] The methods and examples described herein are not inherently related to any particular computer or other device. Various general-purpose systems may be used in accordance with the teachings herein, or it may be advantageous to configure more specialized devices to perform the methods and / or each of their functions, routines, subroutines, or operations described herein. Examples of these diverse system structures are given above.

[0171] The preceding description sets out numerous specific details, such as examples of particular systems, components, and methods, to provide a good understanding of the various embodiments of this disclosure. However, it will be apparent to those skilled in the art that at least some embodiments of this disclosure can be implemented without these specific details. In other examples, well-known components or methods are not described in detail or are presented in simplified block diagram form to avoid unnecessarily obscuring this disclosure. Thus, the specific details set out are merely illustrative. It can be assumed that a particular implementation, different from these exemplary details, is still within the scope of this disclosure. Descriptions of systems in this specification may include descriptions of one or more optional components. Components may be included in combinations not specifically discussed in this disclosure, but may still be within the scope of this disclosure. For example, controllers 390-395 in Figures 3A-3D may be included, either alone or in any combination, in a fluid processing system within the scope of this disclosure.

[0172] Throughout this specification, any reference to “one embodiment” or “one embodiment” means that a particular feature, structure, or characteristic described in relation to that embodiment is included in at least one embodiment. Therefore, the appearance of the phrase “one embodiment” or “one embodiment” in different parts of this specification does not necessarily refer to the same embodiment. Furthermore, the term “or” is inclusive, not exclusive. The terms “about,” “substantially,” or “approximately” in this specification mean that the nominal values ​​shown are accurate within a range of ±10%. Also, terms such as “first,” “second,” “third,” and “fourth” used herein are labels to distinguish different elements and do not necessarily have an ordinal meaning according to their numerical representation.

[0173] As used herein, the terms “above,” “below,” “between,” “placed above,” “before,” “behind,” and “above” refer to the relative position of one material layer or component with respect to another layer or component. For example, when a layer is placed above, above, or below another layer, it may be in direct contact with the other layer or it may have one or more intervening layers. Similarly, a layer placed “between” two layers may be in direct contact with both adjacent layers or it may have one or more intervening layers. Likewise, unless otherwise specified, a feature placed “between” two features may be in direct contact with an adjacent feature or it may have one or more intervening layers or components.

[0174] Although the operations of the methods described herein are shown or described in a specific order, the order of operations of each method is modifiable, and certain operations can be performed in reverse order, or certain operations can be performed at least partially simultaneously with other operations. In other embodiments, instructions or suboperations of different operations may be performed intermittently and / or alternately.

[0175] It should be understood that the above description is intended to be illustrative and not limiting. Many other embodiments will be apparent to those skilled in the art upon reading and understanding the above description. Therefore, the scope of this disclosure should be determined by reference to the appended claims, and each claim should be given to the entire extent of its equivalents.

Claims

1. It is a system, A pressure exchanger (PX) configured to receive a first fluid, receive a second fluid, and exchange pressure between the first fluid and the second fluid, A first heat exchanger configured to receive the second fluid from the PX through a first inlet of the first heat exchanger, receive a third fluid through a second inlet of the first heat exchanger, and exchange heat between the second fluid and the third fluid, A system comprising: a first compressor configured to receive the third fluid from the first heat exchanger.

2. The system according to claim 1, further comprising a first evaporator, the outlet of the first evaporator being in fluid communication with the second inlet of the first heat exchanger.

3. The system according to claim 2, further comprising a second evaporator and a second compressor, wherein the outlet of the second evaporator is in fluid communication with the inlet of the second compressor, and the outlet of the first compressor is in fluid communication with the inlet of the second compressor.

4. The system according to claim 2, wherein the outlet of the first compressor is in fluid communication with the inlet of a gas cooler, and the gas cooler is configured to supply the first fluid to the PX.

5. The system according to claim 2, further comprising a second evaporator, the outlet of the second evaporator being in fluid communication with the second inlet of the first heat exchanger.

6. The system according to claim 2, further comprising a second evaporator, the outlet of the second evaporator being in fluid communication with the inlet of the first compressor.

7. The aforementioned system, Receiver and The system according to claim 1, further comprising an evaporator, wherein the third fluid is supplied from the receiver to the first heat exchanger, and the outlet of the evaporator is in fluid communication with the inlet of the first compressor.

8. The aforementioned system, A gas cooler configured to receive fluid from the first compressor, The system according to claim 1, further comprising a second heat exchanger, wherein the outlet of the gas cooler is in fluid communication with a first inlet of the second heat exchanger, and the first outlet of the second heat exchanger is in fluid communication with the first outlet of the second heat exchanger, and configured to supply the first fluid to the PX.

9. The system according to claim 8, wherein the outlet of the gas cooler is further in fluid communication with the second inlet of the second heat exchanger, and the second outlet of the second heat exchanger corresponds to the second inlet of the second heat exchanger, and is configured to supply the second fluid to the PX.

10. The system according to claim 8, wherein the first outlet of the second heat exchanger is further in fluid communication with the second inlet of the second heat exchanger, and the second outlet of the second heat exchanger corresponds to the second inlet of the second heat exchanger, and is configured to supply the second fluid to the PX.

11. The system according to claim 1, further comprising a pump configured to supply the second fluid to the PX.

12. The system according to claim 11, further comprising a receiver, wherein the pump is configured to obtain the second fluid from the receiver, and the receiver is configured to receive the first fluid from the PX.

13. The aforementioned system, Receiver and The system according to claim 1, further comprising a control valve coupled between the PX and the receiver, wherein the first fluid is supplied from the PX to the receiver through the control valve.

14. The system according to claim 13, further comprising a controller operationally coupled to the control valve, the controller configured to regulate the operation of the control valve to maintain a pressure difference between the receiver associated with the first fluid and the first outlet of the PX.

15. The system according to claim 1, further comprising a high-pressure control valve, the high-pressure control valve configured to regulate the flow of fluid through the first heat exchanger.

16. The system according to claim 15, wherein the high-pressure control valve is operated so that the mass flow rate passing through the high-pressure control valve corresponds to the mass flow rate entering the low-pressure inlet of the PX.

17. The system according to claim 16, further comprising a second control valve for adjusting the flow of the second fluid into the PX, wherein the control of the high-pressure control valve is based on the opening degree of the second control valve.

18. The system further comprises a pump configured to supply the second fluid to the PX, wherein the control of the high-pressure control valve is based on the operating speed of the pump, according to claim 16.

19. The system according to claim 16, wherein the control of the high-pressure control valve is based on a flow meter reading of the fluid supplied to the low-pressure inlet of the PX.

20. It is a method, The characteristics of the working fluid of the refrigeration system supplied to the inlet of the pressure exchanger (PX) are obtained by a processing device, Based on the characteristic display of the working fluid at the inlet of the PX, a first control signal is generated. A method comprising providing the first control signal to a high-pressure control valve that is in fluid communication between the high-pressure outlet of the PX and a receiver, wherein the high-pressure control valve is configured to adjust its operation based on the first control signal.

21. The method according to claim 20, wherein the high-pressure control valve is configured to regulate the flow of the working fluid through a first channel of a heat exchanger coupled between the high-pressure outlet of the PX and the receiver, and the second channel of the heat exchanger is in fluid communication between the evaporator of the refrigeration system and the compressor of the refrigeration system, and the heat exchanger is configured to exchange heat between the working fluid in the first channel and the working fluid in the second channel.

22. The method according to claim 21, wherein the characteristic representation of the working fluid includes one or more measurements taken by a flow meter configured to determine the mass flow rate of the working fluid provided by the high-pressure outlet of the PX.

23. The method according to claim 21, wherein the characteristic indication of the working fluid includes the operating speed of a pump coupled to supply the working fluid to the low-pressure inlet of the PX.

24. The method according to claim 21, wherein the characteristic representation of the working fluid includes a measurement of the temperature of the working fluid at the outlet of the gas cooler of the refrigeration system.

25. The method according to claim 21, wherein the generation of the first control signal is further based on a measurement of the temperature of the working fluid at the inlet of the compressor of the refrigeration system.

26. The method according to claim 20, wherein the characteristic representation of the working fluid includes a fluid temperature associated with the flow of the corresponding fluid through the high-pressure inlet of the PX, and the first control signal is further based on the operating speed of the PX.

27. The method according to claim 26, wherein the first control signal is further based on the fluid temperature associated with each of the fluid flows through the high-pressure control valve.

28. The method according to claim 27, wherein the fluid temperature of the high-pressure control valve is based on a temperature measurement of the working fluid supplied to the inlet of the compressor of the refrigeration system, and the working fluid supplied to the inlet of the compressor has exchanged heat in a heat exchanger with the working fluid flowing through the high-pressure control valve.

29. The method according to claim 26, wherein the refrigeration system comprises a main gas cooler, and the high-pressure control valve is in fluid communication with an auxiliary gas cooler of the refrigeration system.

30. The method according to claim 20, wherein the characteristic indication of the working fluid of the refrigeration system includes an indication of the opening degree of a bypass valve, the bypass valve adjusts a first mass flow rate of the working fluid toward the low-pressure inlet of the pressure exchanger and a second mass flow rate of the working fluid toward the secondary channel of the heat exchanger, and the heat exchanger is configured to exchange heat between the working fluid output by the main gas cooler of the refrigeration system and the working fluid in the secondary channel of the heat exchanger.

31. The method according to claim 30, wherein generating the first control signal includes using the indication of the opening degree of the bypass valve as input to a function or lookup table for determining the target opening degree of the high-pressure control valve.

32. The aforementioned method, To obtain a display of the pressure difference between the receiver and the low-pressure outlet of the PX, A second control signal is generated based on the aforementioned indication of the pressure difference, The method according to claim 20, further comprising providing the second control signal to a second control valve which is in fluid communication between the low-pressure outlet of the PX and the receiver, wherein the second control valve controls the operation of the second control valve based on the second control signal.

33. The method according to claim 32, wherein generating the second control signal includes comparing the pressure difference with a target pressure difference.

34. It is a method, The processing unit obtains the pressure difference between the receiver of the refrigeration system and the low-pressure subsystem associated with the pressure exchanger (PX) of the refrigeration system, Based on the aforementioned indication of the pressure difference, a first control signal is generated, A method comprising providing the first control signal to a control valve that is in fluid communication between the low-pressure outlet of the PX and the receiver, wherein the control valve is configured to adjust its operation based on the first control signal.

35. The method according to claim 34, wherein generating the first control signal includes comparing the pressure difference with a target pressure difference.

36. The aforementioned method, To generate a second control signal, The method according to claim 34, further comprising providing the second control signal to a high-pressure control valve, wherein the high-pressure control valve is configured to regulate the flow of working fluid between the high-pressure outlet of the PX and the receiver.

37. The method according to claim 36, wherein generating the second control signal is based on an indication of the operating speed of the PX and the temperature of the fluid supplied to the high-pressure inlet of the PX.

38. The method according to claim 36, wherein the generation of the second control signal is based on an indication of the operating speed of the PX and the temperature of the fluid supplied to the compressor of the refrigeration system, the refrigeration system comprises a heat exchanger configured to exchange heat between the working fluid output from the high-pressure outlet of the PX and the working fluid supplied to the inlet of the compressor.

Images