Air separation methods, electronic equipment and cold storage

Abstract

This invention provides an air separation method, electronic equipment, and cold storage, belonging to the field of cold storage management technology. The air separation method of this invention utilizes the low-temperature cooling capacity of the cold storage itself and the high-pressure airflow during the defrosting period of the refrigeration system. Without the need for any independent cold source or flow control device, the separation operation is performed simultaneously during the defrosting period, which can complete the separation and emission of non-condensable gases. This avoids the energy consumption of the refrigeration system needing to open the condensation circuit separately under independent separation conditions, and significantly reduces system energy consumption. Furthermore, because a low-temperature zone is formed in the lower half and a higher-temperature zone is formed in the upper half of the collection tank during the separation process, stable and efficient air separation can be achieved by fully relying on the latent heat of phase change and gravity stratification.

Description

Technical Field

[0001] This invention relates to the field of cold storage management technology, and in particular to an air separation method, electronic equipment, and cold storage. Background Technology

[0002] During the long-term operation of industrial and commercial cold storage refrigeration systems, the pressure of the low-pressure evaporator system often falls below standard atmospheric pressure, potentially allowing air to enter the system. Since air is a non-condensable gas, the presence of non-condensable gases in the refrigerant will cause adverse effects such as increased condensing pressure, decreased cooling capacity, and increased power consumption. Therefore, timely removal of non-condensable gases from the refrigeration system is a crucial technical aspect for ensuring its efficient, safe, and long-term operation.

[0003] In existing technologies, methods for removing non-condensable gases are mainly divided into two categories: manual venting and automatic separator methods. Manual venting relies on maintenance personnel manually opening the vent valve at the top of the condenser, which has drawbacks such as inaccurate venting timing, large-scale refrigerant escape, and high labor costs. Automatic separator methods use an independent cold source, such as an auxiliary compressor, to actively condense the refrigerant vapor and then discharge the non-condensable gases.

[0004] However, when using an independent cold source for condensation, the internal gas-liquid flow field within the condenser becomes turbulent, and the high-speed introduction of defrosting gas easily disrupts gravity stratification, resulting in limited separation efficiency. Furthermore, the independent cold source continuously consumes energy, which contradicts the industry trend of energy conservation and emission reduction. Therefore, there is an urgent need for a solution that can efficiently separate non-condensable gases while saving energy. Summary of the Invention

[0005] This invention provides an air separation method, electronic equipment, and cold storage to address the shortcomings of insufficient separation efficiency and energy saving in existing technologies, thereby achieving efficient separation of non-condensable gases while saving energy.

[0006] This invention provides an air separation method applied to a phase change cold storage separation system. The system includes a cold storage insulation panel, a blind-end-facing collection tank, a phase change cold storage jacket, an exhaust valve, and a bypass branch pipe equipped with a control valve. The lower half of the collection tank extends into the low-temperature zone inside the cold storage, while the upper half extends out of the insulation panel and is located in the ambient temperature zone outside the cold storage. The phase change cold storage jacket tightly encloses the lower half of the collection tank. The exhaust valve is located at the top of the upper half of the collection tank. One end of the bypass branch pipe connects to the bottom of the collection tank, and the other end connects to the defrost return gas pipeline of the refrigeration system. The method includes:

[0007] When the refrigeration system of the cold storage is in the refrigeration cycle, the control valve is closed to allow the phase change material in the phase change cold storage jacket to solidify.

[0008] When the refrigeration system starts hot defrosting, the control valve is opened to introduce a mixed gas containing non-condensable gases from the bottom of the collection tank into the collection tank; when the pressure in the collection tank is greater than a preset pressure threshold, the exhaust valve is triggered to open and exhaust gas.

[0009] According to an air separation method provided by the present invention, the phase change cold storage jacket is divided into a first cold storage chamber and a second cold storage chamber along the axial direction of the collection tank, the first cold storage chamber being located below the second cold storage chamber; the first cold storage chamber is filled with a first phase change material with a solid-liquid phase change temperature of a first temperature, and the second cold storage chamber is filled with a second phase change material with a solid-liquid phase change temperature of a second temperature; the first temperature is lower than the second temperature.

[0010] According to an air separation method provided by the present invention, an axisymmetric diffuser is provided at the interface between the bypass branch pipe and the bottom of the collection tank, and an alternating array of arc-shaped baffle fins is fixedly installed directly above the outlet of the diffuser.

[0011] With the control valve remaining open, the arc-shaped baffle fin assembly is used to guide the continuously introduced high-pressure gas to decelerate and form a spiral upward flow pattern.

[0012] According to an air separation method provided by the present invention, the phase change cold storage separation system further includes a phase change heat flow sensor and a processor; the phase change heat flow sensor is attached to the outer wall of the phase change cold storage jacket; the phase change heat flow sensor, the control valve, and the defrosting control module of the refrigeration system are all electrically connected to the processor;

[0013] When the refrigeration system starts hot gas defrosting, opening the control valve includes: the processor determining from the defrosting control module that the refrigeration system has started hot gas defrosting, triggering the control valve to open to a first degree;

[0014] The heat flux density signal of the phase change heat flux sensor around the phase change cold storage jacket is collected in real time; when the heat flux density signal meets the first condition, the control valve is triggered to open to the second opening degree, which is greater than the first opening degree.

[0015] According to an air separation method provided by the present invention, after opening the control valve when the refrigeration system starts hot defrosting, the method further includes:

[0016] If the heat flux density signal does not meet the first condition or a defrosting end signal is received, the control valve is controlled to close.

[0017] According to an air separation method provided by the present invention, a passive differential pressure exhaust valve is provided on the top of the collection tank, and a capillary trapping chamber is provided between the passive differential pressure exhaust valve and the gas-blind end of the collection tank; the capillary trapping chamber is filled with a metal capillary core, and a cooling module is provided on the wall of the capillary trapping chamber.

[0018] According to an air separation method provided by the present invention, the refrigeration system includes multiple sets of evaporator units operating in parallel; the method further includes:

[0019] When multiple evaporator units are defrosting in turn, the remaining latent heat is estimated based on the real-time heat flux integral value of the phase change cold storage jacket. When the remaining latent heat is lower than the estimated consumption for the next defrosting cycle, the defrosting control module of the refrigeration system is controlled to postpone or shorten the defrosting operation of the current cycle.

[0020] According to an air separation method provided by the present invention, the volume of the first cold storage chamber is larger than the volume of the second cold storage chamber, the first temperature is greater than the temperature of the cold storage during the refrigeration cycle, and the second temperature is less than the temperature of the hot defrosting gas.

[0021] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the air separation method as described above.

[0022] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the air separation method as described above.

[0023] The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the air separation method as described above.

[0024] The air separation method, electronic equipment, and cold storage provided by this invention utilize the low-temperature cooling capacity of the cold storage itself and the high-pressure airflow during the defrosting period of the refrigeration system. Without the need for any independent cold source or diversion power device, the separation operation is performed simultaneously during the defrosting period, which can complete the separation and emission of non-condensable gases. This avoids the energy consumption of the refrigeration system having to open the condensation circuit separately under independent separation conditions, and the system energy consumption is significantly reduced. Furthermore, because a low-temperature zone is formed in the lower half and a higher-temperature zone is formed in the upper half of the collection tank during the separation process, stable and efficient air separation can be achieved by fully relying on the latent heat of phase change and gravity stratification. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1 This is one of the structural schematic diagrams of the phase change cold storage separation system provided by the present invention;

[0027] Figure 2 is a schematic flowchart of the air separation method provided by the present invention;

[0028] Figure 3 is a second schematic diagram of the phase change cold storage separation system provided by the present invention;

[0029] Figure 4 is a third schematic diagram of the phase change cold storage separation system provided by the present invention;

[0030] Figure 5 is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0032] The following is combined Figures 1-5 The present invention describes an air separation method, electronic equipment, and cold storage.

[0033] As shown in Figure 1, the air separation method of this invention is applied to a phase change cold storage separation system. The system includes a cold storage insulation panel, a collection tank with the blind end facing upwards, a phase change cold storage jacket, an exhaust valve, and a bypass branch pipe equipped with a control valve. The lower half of the collection tank extends into the low-temperature zone inside the cold storage, and the upper half of the collection tank extends out of the cold storage insulation panel and is located in the normal temperature zone outside the cold storage. The phase change cold storage jacket is sealed around the lower half of the collection tank. The exhaust valve is located at the top of the upper half of the collection tank. One end of the bypass branch pipe is connected to the bottom of the collection tank, and the other end is connected to the defrost return gas pipeline of the refrigeration system.

[0034] The cold storage facility in this embodiment of the invention may include the aforementioned phase change cold storage separation system. The cold storage insulation panel is a plate-shaped component in the cold storage structure used to isolate the low-temperature zone inside the cold storage from the normal-temperature zone outside. It can be composed of a polyurethane foam core board, a rock wool core board, and a metal surface layer. As shown in Figure 1, one side of the cold storage insulation panel can be the normal-temperature zone outside the cold storage, and the other side is the low-temperature zone inside the cold storage.

[0035] The collection tank is a cylindrical pressure vessel with a blind end facing upwards and an opening facing downwards. Its material can be 304 stainless steel or seamless carbon steel, and the axial length of the tank can be from 500mm to 1200mm. It is understood that the collection tank is fixed to the cold storage insulation panel through a perforation method. Perforations matching the outer diameter of the collection tank can be pre-drilled in the insulation panel, and the space between the outer wall of the collection tank and the perforations is sealed with polyurethane foam. The lower half of the collection tank extends vertically into the low-temperature zone inside the cold storage, while the upper half extends vertically and is exposed to the ambient temperature zone outside the cold storage. The length ratio of the lower half to the upper half of the collection tank can be 1.2:1 or 1.8:1, without limitation.

[0036] The phase change energy storage jacket is an annular, sealed cavity surrounding the lower half of the collection tank. Its inner wall is tightly fitted to the outer wall of the collection tank, while its outer wall is an independent outer cylinder wall. A chamber can be formed inside the phase change energy storage jacket, and phase change materials can be injected into it. Phase change materials are functional materials that can undergo a solid-liquid phase change at a specific temperature and absorb or release a large amount of heat in the form of latent heat during the phase change process.

[0037] In some embodiments, the exhaust valve may be located at the top blind end of the upper half of the collection tank, and its valve body outlet is led out to the external atmospheric environment or emission recovery device through an exhaust pipe. The bypass branch pipe is a connecting pipe, one end of which is connected to the pipe joint at the bottom of the collection tank, and the other end is connected in parallel to the hot gas defrosting return pipe of the refrigeration system. A control valve is installed in series on the branch pipe, and the control valve may be a solenoid valve.

[0038] As shown in Figure 2, the air separation method of this embodiment mainly includes step 210 and step 220.

[0039] Step 210: When the refrigeration system of the cold storage is in the refrigeration cycle, control the control valve to close so that the phase change material in the phase change cold storage jacket can be solidified.

[0040] Step 220: When the refrigeration system starts hot defrosting, open the control valve to introduce the mixed gas containing non-condensable gases from the bottom of the collection tank into the collection tank; when the pressure in the collection tank is greater than the preset gas pressure threshold, trigger the exhaust valve to open and exhaust gas.

[0041] During the normal refrigeration cycle of the cold storage, the control valve on the bypass branch of the refrigeration system control loop remains closed. At this time, the connection between the collection tank and the defrosting pipeline at the bottom is cut off. The low-temperature environment inside the cold storage, typically ranging from -18°C to -30°C, continuously transfers cold energy to the phase change storage jacket through the lower half of the metal wall of the collection tank. The phase change material within the jacket gradually cools below its solid-liquid phase change temperature and undergoes a liquid-solid phase change, releasing latent heat and completely solidifying. After solidification, the phase change material continues to cool as the cold storage temperature drops to a steady state below its phase change temperature, thus completing the passive accumulation of cold energy.

[0042] When the refrigeration system initiates hot gas defrosting based on the preset defrosting cycle or evaporator frosting signal, high-temperature, high-pressure refrigerant vapor enters the evaporator from the defrosting branch, flushing the non-condensable gases that have been stored in the evaporator piping into the defrosting return line. At this time, the control valve on the bypass branch is opened, and the refrigerant mixture containing non-condensable gases in the pipeline, driven by its own high pressure, flows back through the bypass branch to the bottom of the collection tank and upwards along the inside of the tank. During this flow, the mixture comes into contact with the lower half of the inner wall of the collection tank, where the temperature is much lower than its own. The refrigerant vapor condenses on the cold wall surface and deposits as droplets. Simultaneously, the solid phase change material in the phase change storage jacket absorbs the heat released by condensation and changes from solid to liquid, continuously releasing the stored cold energy in the form of latent heat.

[0043] During this process, the condensed liquid refrigerant, due to its higher density, settles downwards along the inner wall under gravity and accumulates at the bottom of the collection tank. Non-condensable gases, with a density much lower than the refrigerant liquid and vapor, and which do not undergo phase change at low temperatures, continuously rise to the upper part of the collection tank and accumulate at the top blind end. As the non-condensable gases accumulate, the pressure at the top of the collection tank continuously increases. Under these conditions, opening the exhaust valve allows the accumulated non-condensable gases to be discharged from the refrigeration system.

[0044] According to the air separation method provided in the embodiments of the present invention, by utilizing the low-temperature cooling capacity of the cold storage itself and the high-pressure airflow during the defrosting period of the refrigeration system, the separation operation can be performed simultaneously during the defrosting period without the need for any independent cold source or diversion power device. This can complete the separation and emission of non-condensable gases, avoiding the energy consumption of the refrigeration system having to open the condensation circuit additionally under independent separation conditions, and significantly reducing system energy consumption. Furthermore, since a low-temperature zone in the lower half and a higher-temperature zone in the upper half are formed in the collection tank during the separation process, stable and efficient air separation can be achieved by fully relying on the latent heat of phase change and gravity stratification.

[0045] As shown in Figure 3, in some embodiments, the phase change cold storage jacket is divided into a first cold storage chamber and a second cold storage chamber along the axial direction of the collection tank. The first cold storage chamber is located below the second cold storage chamber. The first cold storage chamber is filled with a first phase change material with a solid-liquid phase change temperature of a first temperature, and the second cold storage chamber is filled with a second phase change material with a solid-liquid phase change temperature of a second temperature. The first temperature is lower than the second temperature.

[0046] The first and second cold storage chambers can be separated by an annular partition. The phase change cold storage jacket can be divided along the axial direction of the collecting tank by the annular partition into two vertically connected, independent, and non-transferring sealed cavities. The outer edge of the annular partition can be welded to the outer cylinder of the jacket for sealing, and the inner edge can be welded to the outer wall of the lower half of the collecting tank for sealing, ensuring that no crossflow of phase change material occurs between the two cavities. The first cold storage chamber is located at the bottom, near the bottom inlet section of the collecting tank; the second cold storage chamber is located at the top, near the middle section upwards from the inlet of the collecting tank.

[0047] A first phase change material is filled in a first cold storage chamber, and its solid-liquid phase transition temperature is a first temperature T1; a second phase change material is filled in a second cold storage chamber, and its solid-liquid phase transition temperature is a second temperature T2, satisfying T1 < T2. For example, the first phase change material can be a material of an inorganic salt eutectic aqueous solution system, and the second phase change material can be a material of a high-purity water phase change system.

[0048] During the cold storage stage, the low-temperature environment of the cold storage acts on both chambers simultaneously. Since T1 < T2, the second phase change material reaches its phase change temperature first and solidifies first, followed by the first phase change material continuing to cool down and solidifying at an even lower temperature. Ultimately, the two chambers can form a tiered cold storage system along the axial direction, with the lower layer having a lower temperature and the upper layer having a slightly higher temperature.

[0049] The mixed gas delivered by the hot defrosting system is characterized by its high temperature and low density. When it enters from the bottom, due to its strong thermal buoyancy, it does not immediately diffuse to the surrounding cold walls, but instead forms an upward central hot jet. After reaching the top, the high-temperature gas loses its kinetic energy and, upon encountering the cooler wall surface, begins to tumble outwards and downwards, flowing down the inner wall. At this point, the high-temperature gas first comes into contact with the wall surface of the second cold storage chamber located above.

[0050] At this stage, the gas contains a large amount of high-partial-pressure refrigerant vapor, which is highly condensable. The relatively high temperature T2 of the second cold storage chamber is sufficient to cause some of the refrigerant to release its latent heat and become liquid. The gas continues to flow down the wall, and after condensation in the second cold storage chamber, the temperature of the mixed gas has decreased, and some of the refrigerant vapor has been extracted. At this point, the partial pressure of the refrigerant in the remaining gas drops sharply. According to thermodynamic principles, the lower the partial pressure of a gas, the lower its corresponding condensation dew point temperature. At this point, at the second temperature, it is no longer possible to condense the remaining rarefied refrigerant vapor. Therefore, the liquefied refrigerant, the refrigerant whose temperature rises again due to the influence of the subsequent high-temperature gas and becomes gaseous again, and the gas flow containing residual refrigerant descend along the wall to the bottom of the first cold storage chamber area, contacting the even colder deep-cooled wall surface. The strong cooling capacity of the first cold storage chamber liquefies the remaining refrigerant vapor, achieving deep condensation.

[0051] Understandably, during the defrosting stage, the high-temperature mixed gas from the bypass branch enters from the bottom of the collection tank and rises. The gas first contacts the inner wall section of the collection tank corresponding to the second cold storage chamber. The temperature difference between the second temperature and the high-temperature gas is moderate, achieving buffer condensation: the gas temperature drops sharply from the defrosting high temperature to near the second temperature, and some refrigerant vapor condenses and precipitates in this section; the uncondensed residual gas and the refrigerant in the lower part of the collection tank, which has been heated by the subsequent high-temperature gas and turned back into a gaseous state, contact the inner wall section of the collection tank corresponding to the first cold storage chamber. The wall temperature in this section is even lower, and the residual refrigerant vapor is further condensed.

[0052] It should be noted that with a single phase change temperature cold storage jacket, if the phase change temperature is too low during the defrosting period, complete crystallization is difficult to achieve during the refrigeration period, resulting in insufficient cold storage capacity; if the phase change temperature is too high, condensation will be incomplete during the defrosting period, and the gas exiting the tank will still contain a large amount of refrigerant vapor. This embodiment, through the design of staggered phase change temperatures in the upper and lower cavities, allows the upper second cold storage cavity to act as a thermal buffer layer to bear the main thermal shock and protect the low-temperature deep condensation capacity of the first cold storage cavity from being depleted by instantaneous high temperatures; at the same time, it enables the first cold storage cavity to continuously release heat to the gravity-stratified refrigerant and mixed gas throughout the entire defrosting cycle, significantly improving the condensation efficiency of the refrigerant.

[0053] In some embodiments, the volume of the first cold storage chamber is larger than the volume of the second cold storage chamber, the first temperature is greater than the temperature of the cold storage during the refrigeration cycle, and the second temperature is less than the temperature of the hot defrosting gas.

[0054] The volume of the first cold storage chamber is larger than that of the second cold storage chamber. The ratio of the volume of the first cold storage chamber to the volume of the second cold storage chamber can be in the range of 1.5:1 to 2.5:1. The temperature of the cold storage during the refrigeration cycle can be in the low-temperature range of -18℃ to -30℃; the temperature of the hot gas defrosting gas can be in the high-temperature range of 60℃ to 90℃.

[0055] For example, T1 can be 3°C to 6°C higher than the internal ambient temperature of the cold storage. For instance, if the cold storage is at -25°C, T1 can be in the range of -22°C to -19°C. T2 can be about 8°C to 15°C higher than T1, meaning T2 can be in the range of -14°C to -4°C, and T2 is significantly lower than the defrosting gas temperature. T1 being only 3°C to 6°C higher than the cold storage temperature ensures that the first phase change material can passively complete crystallization under the cold storage environment's cooling capacity during the normal refrigeration cycle of the cold storage without the need for any additional cold source. T2 being about 8°C to 15°C higher than T1 ensures that the second phase change material melts rapidly under the impact of high-temperature gas during the defrosting period, playing a buffering role, and preventing the residual gas leaving the tank from still containing a large amount of refrigerant vapor due to excessively high temperatures.

[0056] The first cold storage chamber has a larger volume to accommodate most of the latent heat absorption during deep condensation, and its large amount of phase change material ensures a continuous and stable output of cold energy in the later stages of defrosting. The second cold storage chamber has a smaller volume because it only undertakes the task of "buffering condensation" during the initial stage of defrosting. An excessively large volume would prolong the time required for complete crystallization and reduce the cold storage response speed.

[0057] Understandably, the volume and parameters of the two cold storage chambers can be matched and set according to the actual refrigeration operating temperature of the cold storage and the amount of refrigerant, so as to achieve optimal synergy in the time distribution and latent heat distribution of the two-stage action of buffer condensation and deep condensation.

[0058] In some embodiments, as shown in FIG4, an axisymmetric diffuser is provided at the interface between the bypass branch pipe and the bottom of the collection tank, and an alternating array of arc-shaped baffle fins is fixedly installed directly above the outlet of the diffuser.

[0059] With the control valve remaining open, the arc-shaped baffle fins are used to guide the continuously introduced high-pressure gas to decelerate and form a spiral upward flow pattern.

[0060] In some embodiments, the diffuser is an axisymmetric tapered transition section with a small inlet diameter and a large outlet diameter, its inlet end connected to a bypass branch pipe, and its outlet end connected to the bottom opening of the collection tank. Exemplarily, the axial length of the diffuser can be 2 to 5 times the inlet diameter.

[0061] The arc-shaped baffle fin assembly consists of several metal fins with a certain curvature, arranged alternately inside the collection tank directly above the diffuser outlet. One end of the fin is welded and fixed to the inner wall of the collection tank, while the other end extends towards the center of the tank but does not completely close the cross-section. Adjacent fins are staggered circumferentially to form a spiral meandering channel.

[0062] It should be noted that at the moment the control valve opens and the mixed gas rushes into the bypass branch at high speed, the airflow velocity can reach several meters per second or even tens of meters per second. If the gas rushes directly into the collection tank at this original velocity, it will violently agitate the settled liquid refrigerant in a turbulent manner and re-atomize it, disrupting the gas-liquid stratification. At the same time, the high-speed direct airflow is prone to forming a short-circuit channel in the middle of the collection tank, causing most of the mixed gas to reach the top of the tank before it has fully contacted the cold wall, severely reducing the condensation efficiency.

[0063] After the diffuser is installed, the airflow first undergoes a cross-sectional expansion process before entering the collection tank. According to the principle of continuity, the gas velocity is greatly reduced and enters the laminar or transitional flow range. Subsequently, the gas is forcibly guided by the staggered arc-shaped baffle fins, forming a spiral upward flow pattern along the arc direction of the fins, and the flow path is greatly extended.

[0064] In this embodiment, by using a combination structure of deceleration followed by turbulence, the residence time of the mixed gas in the collection tank is extended without compromising the stability of the gas-liquid gravity stratification interface. This significantly increases the contact area and duration between the gas and the cold wall, thereby improving the condensation and liquefaction efficiency of the refrigerant vapor. At the same time, the overall flow rate is reduced, avoiding agitation and re-atomization of the liquid refrigerant at the bottom, thus stabilizing the condensation process after gravity stratification.

[0065] In some embodiments, the phase change cold storage separation system further includes a phase change heat flow sensor and a processor; the phase change heat flow sensor is attached to the outer wall of the phase change cold storage jacket; the phase change heat flow sensor, the control valve, and the defrosting control module of the refrigeration system are all electrically connected to the processor.

[0066] When the refrigeration system starts hot gas defrosting, the control valve is opened, including: the processor determines from the defrosting control module that the refrigeration system has started hot gas defrosting, and triggers the control valve to open to the first opening degree; the heat flux density signal of the heat flux sensor on the periphery of the phase change cold storage jacket is collected in real time; when the heat flux density signal is detected to meet the first condition, the control valve is triggered to open to the second opening degree, which is greater than the first opening degree.

[0067] A phase change heat flux sensor can be a thin-film sensor that can directly output the wall normal heat flux density signal q(t), in units of W / m². The phase change heat flux sensor can be attached to the outer wall of the phase change cold storage jacket, for example, by using thermally conductive adhesive and covering it with insulation cotton to eliminate environmental interference.

[0068] The processor is an industrial controller such as a PLC, embedded MCU, or computer host with signal acquisition, data processing, and digital output functions. It is connected to the phase change heat flow sensor through a shielded signal line and to the coil drive terminal of the control valve. At the same time, it interacts with the defrosting control module of the refrigeration system through an industrial communication bus such as RS485.

[0069] The first condition can be a preset criterion for determining whether the condensation temperature field has been established. Specifically, it can be set as follows: the first derivative of the heat flux density signal q(t) with respect to time, dq / dt, exceeds a certain multiple of the steady-state heat flux q0 for N consecutive sampling periods. In one example, N can be 3, that is, it exceeds 3 times the steady-state value for 3 consecutive periods.

[0070] The control valve can be a proportional solenoid valve or a stepper electric regulating valve with multi-stage opening adjustment capability. Its valve core opening can be continuously or steppedly adjusted within the range of fully closed to fully open under the action of the command signal output by the processor.

[0071] The first opening degree refers to the smaller opening degree maintained when the control valve is initially triggered and opened, which can limit the mixed gas to enter the collection tank slowly at a small flow rate; the second opening degree refers to the larger opening degree to which the control valve switches after the condensation temperature field is fully established, which can allow the mixed gas to be introduced into the collection tank at a normal flow rate for efficient condensation and separation.

[0072] It should be noted that the control valve opening process in this embodiment adopts a two-stage progressive opening control strategy, and the specific operation process is as follows.

[0073] Phase 1: Defrosting Signal Triggering Phase. The processor monitors the operating status of the defrosting control module of the refrigeration system in real time via the industrial communication bus. Upon detecting the start of hot gas defrosting or a switching signal, the processor outputs a first-level command signal, driving the control valve from fully closed to the first opening degree. At this time, the bypass branch maintains only a small flow rate, and a portion of the high-temperature mixed gas containing non-condensable gases in the defrosting return gas pipeline slowly seeps into the collection tank at a low velocity and flow rate. When this low-flow gas contacts the lower half of the inner wall of the collection tank, it begins to preheat the phase change cold storage jacket, initiating the initial melting of the phase change material boundary, while avoiding a sudden and severe thermal shock to the already established low-temperature wall surface.

[0074] Phase Two: Heat Flow Feedback Monitoring Phase. During the initial opening of the control valve, the processor enters a high-frequency signal sampling mode, acquiring the heat flux density signal q(t) output by the heat flux sensor on the periphery of the phase change cold storage jacket at fixed time intervals, and calculating its first derivative dq / dt in real time. Initially, the small flow of gas has not yet caused significant condensation heat release on the wall surface, and the heat flux density signal fluctuates near its steady-state value, not meeting the first condition. The processor maintains the control valve at the first opening. As the small-flow pre-introduction process continues, the phase change boundary inside the phase change material begins to move significantly, and latent heat continues to be released outwards. The heat flux density on the outer wall of the jacket rapidly increases. When dq / dt exceeds the set threshold for multiple consecutive sampling cycles, the first condition is determined to be met, meaning that a stable stepped condensation temperature field has been established on the inner wall of the collection tank, enabling it to condense large-flow, high-temperature mixed gas.

[0075] Once the processor confirms that the first condition is met, it can output a second-level command signal to drive the control valve to switch from the first opening degree to the second opening degree. At this time, the flow cross-section of the bypass branch pipe is significantly expanded, and the high-temperature mixed gas containing non-condensable gases is introduced into the collection tank at a normal flow rate, entering a process of high-flow-rate stepped directional condensation, gravity stratification, and passive exhaust, thereby achieving stable exhaust.

[0076] Understandably, if the control valve is fully opened to the second degree immediately upon the start of defrosting, a large amount of high-temperature mixed gas will rush in before the phase change material has established a stable melting boundary and before the wall surface is at an extremely low temperature. This thermal shock will trigger a violent, instantaneous phase change locally on the wall surface, causing the phase change material to melt rapidly. A large amount of phase change material will melt in a short period, and the cooling capacity will not match the gas condensation demand in time, resulting in an imbalance where there is excess cooling capacity wasted in the early stages and insufficient cooling capacity attenuated in the later stages. The small flow rate pre-introduction at the first degree of opening provides a gradual preheating transition window for the phase change material, making the phase change process more stable.

[0077] This implementation actively triggers the change in phase change heat flux signal by pre-introducing a small flow rate, and confirms the condensation capacity in a closed loop through heat flux feedback. Only after the wall condensation capacity has been verified by actual measurement is the system switched to a large flow rate condition, which can avoid the situation of incomplete and unstable condensation caused by premature introduction of flow.

[0078] Furthermore, different cold storage temperatures, defrosting durations, and defrosting gas temperatures all affect the establishment rhythm of the condensation temperature field. In this embodiment, the criteria for determining the first condition and the magnitudes of the first and second openings can be set according to the actual situation of the system, enabling the switching node of the control valve to adaptively move forward or backward according to the actual operating conditions, significantly improving the robustness of the separation system under varying operating conditions.

[0079] Understandably, upon receiving the defrosting start signal from the refrigeration system, the proportional control valve is first opened to a preset initial small opening to introduce a trial mixed gas into the collection tank. By real-time acquisition of the heat flux density signal from the heat flux sensor surrounding the second cold storage chamber, when the introduced gas begins to condense, causing the monitored heat flux density to show a characteristic jump greater than the preset threshold, it is determined that the buffer condensation temperature field has been stably established. At this time, the system controller controls the proportional control valve to increase to full opening or the target operating opening.

[0080] When the refrigeration system starts hot gas defrosting, after opening the control valve, the method further includes: if the heat flux density signal does not meet the first condition or a defrosting end signal is received, controlling the control valve to close.

[0081] After the control valve opens and initiates condensation, the processor enters a monitoring state, continuously acquiring signals from the phase change heat flux sensor. The phase change heat flux sensor can be attached to the outer wall of the first cold storage chamber of the phase change cold storage jacket. When the heat flux density signal corresponding to the outer wall of the first cold storage chamber falls below a preset reset threshold, it indicates that the latent heat reserve of the first phase change material has been largely released, and the condensation driving capacity has significantly decreased. Continuing condensation is meaningless and would cause uncondensed refrigerant vapor to be discharged along with the non-condensable gas. Alternatively, before the phase change material's cooling capacity is exhausted, the refrigeration system itself has output a defrosting end signal, indicating that the source of the mixed gas has stopped. Continuing to keep the valve open will only cause the pressure inside the collection tank to decrease and disrupt the stratification state. In both cases, the processor can output a valve-closing command, closing the control valve, re-blocking the connection between the collection tank and the defrosting return gas pipeline, and allowing the phase change material to re-enter the cold storage stage.

[0082] In this embodiment, ineffective escape of refrigerant during the exhaust process can be avoided, as well as condensation failure caused by continued flow after excessive consumption of phase change material; and it can be ensured that the separation system can return to the next cold storage process after each defrosting cycle.

[0083] A passive differential pressure exhaust valve is installed at the top of the collection tank, and a capillary trapping chamber is provided between the passive differential pressure exhaust valve and the gas-blind end of the collection tank; the capillary trapping chamber is filled with a metal capillary core, and a cooling module is provided on the wall of the capillary trapping chamber.

[0084] A passive differential pressure exhaust valve can be a purely mechanical one-way exhaust valve with an internal calibration spring, sealing valve core and valve seat. Its opening pressure is determined by the spring force and does not rely on any electronic control drive or sensor judgment. It is a purely passive physical triggering component.

[0085] The gas blind end is a cavity structure formed by the closed configuration of the upper half of the collection tank, used to temporarily store non-condensable gases.

[0086] The capillary trapping chamber is a transitional cavity connected in series between the passive differential pressure exhaust valve and the blind end of the gas-containing collection tank. The chamber is tightly filled with a metal capillary core, which has a high specific surface area and strong capillary adsorption force. The metal capillary core can be a copper mesh sintered capillary core or a stainless steel fiber capillary core, etc.

[0087] The capillary trapping cavity is equipped with a cooling module on its wall. This cooling module can be a semiconductor cooling chip (Peltier element). Its hot side dissipates heat to the ambient temperature outside the cold storage through heat dissipation fins, while its cold side is in close contact with the outer wall of the capillary trapping cavity. The inner wall of the capillary trapping cavity can be bonded to the metal capillary core with thermally conductive adhesive.

[0088] When the accumulation of non-condensable gas at the top of the collection tank reaches the opening threshold of the passive differential pressure exhaust valve, the exhaust valve opens passively, and the enriched gas is discharged outward from the blind end of the self-contained gas. During the discharge process, the gas first passes through the capillary trapping chamber. Because the walls of the capillary trapping chamber are actively cooled to a low temperature by the semiconductor refrigeration chip, the temperature of the gas is further lowered to a level far below the saturation temperature of the residual refrigerant vapor as it flows through the chamber. The residual trace amount of refrigerant vapor is condensed into droplets on the high specific surface area of ​​the metal capillary core. The condensed droplets remain inside the capillary core due to the strong capillary force of the capillary core and are not blown out with the airflow. After the exhaust is completed and the airflow stops, these retained liquid refrigerants gradually flow back into the collection tank along the capillary core under the action of gravity.

[0089] In this embodiment, by adding an actively cooled capillary trapping component to the exhaust path, the volume fraction of residual refrigerant in the exhaust gas can be significantly reduced; the refrigeration module only operates for a short time during the exhaust moment, unlike an independent cold source that operates for a long time, and the system energy consumption is lower than that of a conventional active separator.

[0090] In some embodiments, the refrigeration system includes multiple sets of evaporator units operating in parallel; the method further includes: when multiple sets of evaporator units are defrosting in turn, estimating the remaining latent heat based on the real-time heat flux integral value of the phase change cold storage jacket, and when the remaining latent heat is lower than the estimated consumption for the next defrosting cycle, controlling the defrosting control module of the refrigeration system to postpone or shorten the defrosting operation of the current cycle.

[0091] Multiple evaporator units operating in parallel refer to two or more evaporator branches configured in a refrigeration system under the support of the same compressor unit. Each branch shares a common suction main pipe but is equipped with an independent hot gas defrosting branch and a defrosting solenoid valve. They can take turns entering the hot gas defrosting state under the scheduling of the defrosting control module of the refrigeration system.

[0092] The real-time heat flux integral value is the cumulative integral of the heat flux density signal q(t) output by the heat flux sensor on the outer wall of the phase change cooling jacket in the time domain, representing the cumulative latent heat released by the phase change material since the last complete cooling.

[0093] When the refrigeration system adopts a strategy of multiple evaporator units taking turns to defrost, each round of defrosting will trigger a priming-condensing-exhausting operation of this separation system. If the interval between two adjacent defrostings is too short or the temperature of the cold storage is too high, resulting in insufficient time for the phase change material to recrystallize completely, the phase change material may not fully recover its cooling capacity before entering the next priming round, which will lead to a decrease in condensing capacity and refrigerant entrainment in the exhaust.

[0094] In this embodiment, the heat flux signal is continuously integrated during each heat transfer process to obtain Q(t), from which the remaining latent heat Q of the phase change material is inferred. remain = Q total Q(t). Before the next evaporator defrosting start, the processor will... remain Compare with the average consumption of each defrosting cycle: If Q remain If the consumption is lower than the estimated amount, the processor sends a feedback signal to the defrosting control module of the refrigeration system, requesting to postpone the current defrosting cycle to wait for the phase change material to recrystallize, or to shorten the defrosting time of the current cycle and limit the amount of mixed gas entering, so as to ensure sufficient cooling capacity each time it is drawn in.

[0095] It is understandable that this implementation incorporates the cold energy status of the separation system into the defrosting scheduling decision of the refrigeration system, avoiding separation failure caused by the overdraft of the cold energy of the phase change material when multiple evaporators are defrosted in turn. This can improve the stability and long-term reliability of non-condensable gas separation in large multi-evaporator cold storage systems.

[0096] Figure 5 illustrates a schematic diagram of the physical structure of an electronic device. As shown in Figure 5, the electronic device may include: a processor 510, a communication interface 520, a memory 530, and a communication bus 540. The processor 510, communication interface 520, and memory 530 communicate with each other via the communication bus 540. The processor 510 can call logical instructions in the memory 530 to execute an air separation method. This method includes: when the refrigeration system of the cold storage is in a refrigeration cycle, controlling the control valve to close so that the phase change material in the phase change cold storage jacket solidifies; when the refrigeration system starts hot defrosting, opening the control valve to introduce a mixed gas containing non-condensable gases from the bottom of the collection tank into the collection tank; and when the pressure in the collection tank exceeds a preset pressure threshold, triggering the exhaust valve to open and exhaust gas.

[0097] Furthermore, the logical instructions in the aforementioned memory 530 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0098] On the other hand, the present invention also provides a cold storage, which may include the electronic equipment of the foregoing embodiments. The cold storage of the present invention may also include the foregoing phase change cold storage separation system.

[0099] On the other hand, the present invention also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer is able to execute the air separation method provided by the above methods. The method includes: when the refrigeration system of the cold storage is in a refrigeration cycle, controlling the control valve to close so that the phase change material in the phase change cold storage jacket solidifies; when the refrigeration system starts hot defrosting, opening the control valve to introduce a mixed gas containing non-condensable gases from the bottom of the collection tank into the collection tank; and when the pressure in the collection tank is greater than a preset pressure threshold, triggering the exhaust valve to open and exhaust gas.

[0100] In another aspect, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the air separation method provided by the above methods, the method comprising: when the refrigeration system of the cold storage is in a refrigeration cycle, controlling a control valve to close so as to solidify the phase change material in the phase change cold storage jacket; when the refrigeration system starts hot defrosting, opening a control valve to introduce a mixed gas containing non-condensable gases from the bottom of the collection tank into the collection tank; and when the pressure in the collection tank is greater than a preset pressure threshold, triggering an exhaust valve to open and exhaust gas.

[0101] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0102] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method of air separation, characterized by, The method is applied to a phase change cold storage separation system, which includes a cold storage insulation panel, a blind-end-facing collection tank, a phase change cold storage jacket, an exhaust valve, and a bypass branch pipe equipped with a control valve. The lower half of the collection tank extends into the low-temperature zone inside the cold storage, while the upper half extends out of the cold storage insulation panel and is located in the ambient temperature zone outside the cold storage. The phase change cold storage jacket tightly encloses the lower half of the collection tank. The exhaust valve is located at the top of the upper half of the collection tank. One end of the bypass branch pipe is connected to the bottom of the collection tank, and the other end is connected to the defrost return gas pipeline of the refrigeration system; the method includes: When the refrigeration system of the cold storage is in the refrigeration cycle, the control valve is closed to allow the phase change material in the phase change cold storage jacket to solidify. When the refrigeration system starts hot defrosting, the control valve is opened to introduce a mixed gas containing non-condensable gases from the bottom of the collection tank into the collection tank; when the pressure in the collection tank is greater than a preset pressure threshold, the exhaust valve is triggered to open and exhaust gas. The phase change cold storage jacket is divided into a first cold storage chamber and a second cold storage chamber along the axial direction of the collection tank. The first cold storage chamber is located below the second cold storage chamber. The first cold storage chamber is filled with a first phase change material with a solid-liquid phase change temperature of a first temperature, and the second cold storage chamber is filled with a second phase change material with a solid-liquid phase change temperature of a second temperature. The first temperature is lower than the second temperature. The phase change cold storage separation system also includes a phase change heat flow sensor and a processor; the phase change heat flow sensor is attached to the outer wall of the phase change cold storage jacket; the phase change heat flow sensor, the control valve and the defrosting control module of the refrigeration system are all electrically connected to the processor. When the refrigeration system starts hot gas defrosting, opening the control valve includes: the processor determining from the defrosting control module that the refrigeration system has started hot gas defrosting, triggering the control valve to open to a first degree; The heat flux density signal of the phase change heat flux sensor around the phase change cold storage jacket is collected in real time; when the heat flux density signal meets the first condition, the control valve is triggered to open to the second opening degree, which is greater than the first opening degree.

2. The air separation method according to claim 1, characterized in that, The interface between the bypass branch pipe and the bottom of the collection tank is provided with an axisymmetric diffuser, and an alternating array of arc-shaped baffle fins is fixedly installed directly above the outlet of the diffuser. With the control valve remaining open, the arc-shaped baffle fin assembly is used to guide the continuously introduced high-pressure gas to decelerate and form a spiral upward flow pattern.

3. The air separation method according to claim 1, characterized in that, After opening the control valve when the refrigeration system starts hot defrosting, the method further includes: If the heat flux density signal does not meet the first condition or a defrosting end signal is received, the control valve is controlled to close.

4. The air separation method according to claim 1, characterized in that, A passive differential pressure exhaust valve is provided at the top of the collection tank, and a capillary trapping chamber is provided between the passive differential pressure exhaust valve and the gas-blind end of the collection tank; the capillary trapping chamber is filled with a metal capillary core, and a cooling module is provided on the wall of the capillary trapping chamber.

5. The air separation method according to claim 1, characterized in that, The refrigeration system includes multiple evaporator units operating in parallel; the method further includes: When multiple evaporator units are defrosting in turn, the remaining latent heat is estimated based on the real-time heat flux integral value of the phase change cold storage jacket. When the remaining latent heat is lower than the estimated consumption for the next defrosting cycle, the defrosting control module of the refrigeration system is controlled to postpone or shorten the defrosting operation of the current cycle.

6. The air separation method according to claim 1, characterized in that, The volume of the first cold storage chamber is larger than that of the second cold storage chamber, the first temperature is greater than the temperature of the cold storage during the refrigeration cycle, and the second temperature is less than the temperature of the hot defrosting gas.

7. An electronic device comprising a memory, a processor, and a computer program stored in the memory and capable of running on the processor, characterized in that, When the processor executes the program, it implements the air separation method as described in any one of claims 1 to 6.

8. A cold storage facility, characterized in that, The cold storage includes the electronic equipment as described in claim 7.

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