Waste heat recovery method and control device, waste heat recovery system, and storage medium

Abstract

The present disclosure provides a waste heat recovery method and control device, a waste heat recovery system and a storage medium. The waste heat recovery method comprises: detecting the temperature of the cooling liquid in the first liquid storage tank located in the waste heat recovery circuit, wherein the waste heat recovery circuit comprises a first liquid storage tank, a heat pump, a cooling tower, a second liquid storage tank and a refrigeration heat exchanger connected in series by a cooling liquid pipeline, and the temperature of the cooling liquid in the first liquid storage tank is higher than the temperature of the cooling liquid in the second liquid storage tank; in the case that the temperature of the cooling liquid in the first liquid storage tank is higher than the heat pump temperature threshold, the cooling branch is started to reduce the temperature of the cooling liquid at the inlet of the heat pump by using the cooling liquid in the cooling branch.

Description

Technical Field

[0001] This disclosure relates to the field of waste heat recovery, and in particular to a waste heat recovery method and control device, a waste heat recovery system and a storage medium. Background Technology

[0002] With increasingly stringent requirements for energy conservation and consumption reduction in industry, the use of heat pump systems for waste heat recovery has become an important means to improve energy efficiency.

[0003] Traditional waste heat recovery and heat pump systems suffer from instability, low energy efficiency, high investment, and poor reliability due to fluctuations in cooling processes, asynchronous start-up and shutdown of heat pumps, and changes in heat source temperature. Furthermore, direct heating from high-temperature water tanks lacks a control mechanism, making them prone to heat pump overheating failures. Moreover, to address asynchronous operation and large fluctuations, high- and low-temperature water tanks often require large capacities, leading to increased costs. Summary of the Invention

[0004] The inventors noted that, in related technologies, waste heat recovery systems generally suffer from technical problems such as unstable heat pump operation, large temperature fluctuations, insufficient cascade utilization of waste heat, poor adaptability to operating conditions, and excessively high investment costs.

[0005] Accordingly, this disclosure provides a waste heat recovery method, which detects the temperature of the coolant in the first storage tank in the waste heat recovery loop. When the temperature of the coolant in the first storage tank is greater than the heat pump temperature threshold, the cooling branch is opened to reduce the cooling temperature at the heat pump inlet, thereby improving the energy supply stability, safety and economy of the waste heat recovery system.

[0006] In a first aspect of this disclosure, a waste heat recovery method is provided, comprising: detecting the temperature of coolant in a first storage tank located in a waste heat recovery loop, wherein the waste heat recovery loop includes a first storage tank, a heat pump, a cooling tower, a second storage tank, and a refrigeration heat exchanger connected in series by coolant pipelines, and the temperature of coolant in the first storage tank is greater than the temperature of coolant in the second storage tank. When the temperature of coolant in the first storage tank is greater than a heat pump temperature threshold, a cooling branch is activated to utilize the coolant in the cooling branch to lower the coolant temperature at the heat pump inlet.

[0007] In some embodiments, the cooling branch includes a first branch, wherein a first end of the first branch is connected to the inlet of the heat pump, and the other end of the first branch is connected to a third reservoir. Activating the cooling branch includes: detecting the liquid level in the third reservoir. If the liquid level in the third reservoir is higher than the lower limit of the liquid level in the third reservoir, the first branch is activated to utilize the coolant in the third reservoir to lower the coolant temperature at the inlet of the heat pump.

[0008] In some embodiments, after opening the first branch, the method further includes: detecting the temperature of a first mixed coolant at the connection point between the coolant pipeline and the first end of the first branch; and adjusting the opening of a control valve on the first branch and the opening of a control valve at the outlet of the first reservoir based on the first mixed coolant temperature.

[0009] In some embodiments, it is detected whether the temperature of the first mixed coolant is greater than the heat pump temperature threshold. If the temperature of the first mixed coolant is greater than the heat pump temperature threshold, it is detected whether the opening of the control valve on the first branch is at its maximum opening. If the opening of the control valve on the first branch is not at its maximum opening, the opening of the control valve on the first branch is increased.

[0010] In some embodiments, the cooling branch further includes a second branch, a first end of which is connected to the inlet of the heat pump, and the other end of which is connected to a second storage tank. The waste heat recovery method further includes: if the control valve on the first branch is at its maximum opening, opening the second branch to utilize the coolant in the second storage tank to lower the coolant temperature at the inlet of the heat pump.

[0011] In some embodiments, the temperature of the second mixed coolant at the junction of the coolant line and the first end of the second branch is detected. The opening of the control valve on the second branch and the opening of the control valve at the outlet of the first reservoir are adjusted according to the temperature of the second mixed coolant.

[0012] In some embodiments, if the liquid level in the third liquid tank is not higher than the lower limit of the liquid level in the third liquid tank, the second branch is opened so as to use the coolant in the second liquid tank to reduce the coolant temperature at the inlet of the heat pump.

[0013] In some embodiments, it is detected whether the liquid level in the first reservoir is greater than a first preset value. If the liquid level in the first reservoir is greater than the first preset value, a first bypass is opened to allow the coolant in the first reservoir to flow into a third reservoir.

[0014] In some embodiments, if the liquid level in the first liquid tank is not greater than a first preset value, it is detected whether the liquid level in the first liquid tank is greater than a second preset value, wherein the first preset value is greater than the second preset value. If the liquid level in the first liquid tank is greater than the second preset value, the step of detecting the temperature of the coolant in the first liquid tank located in the waste heat recovery loop is executed.

[0015] In some embodiments, it is detected whether the temperature of the coolant at the inlet of the cooling tower is greater than a preset temperature of the second storage tank. If the temperature of the coolant at the inlet of the cooling tower is greater than the preset temperature of the second storage tank, the cooling tower is turned on to reduce the temperature of the coolant at the inlet of the cooling tower.

[0016] In a second aspect of this disclosure, a waste heat recovery control device is provided, comprising: a memory configured to store instructions; and a processor coupled to the memory, the processor being configured to execute the method described in any of the above embodiments based on the instructions stored in the memory.

[0017] In a third aspect of this disclosure, a waste heat recovery system is provided, comprising: the waste heat recovery control device described in the above embodiments; a waste heat recovery loop, comprising a first liquid storage tank, a heat pump, a cooling tower, a second liquid storage tank, and a refrigeration heat exchanger connected in series by a coolant pipeline, wherein the coolant temperature in the first liquid storage tank is greater than the coolant temperature in the second liquid storage tank; a cooling branch configured to, when in an open state according to the control of the waste heat recovery control device, utilize the coolant in the cooling branch to reduce the coolant temperature at the inlet of the heat pump; and a first temperature sensor configured to detect the temperature of the first liquid storage tank located in the waste heat recovery loop.

[0018] In some embodiments, the cooling branch includes a first branch, wherein a first end of the first branch is connected to the inlet of the heat pump, and the other end of the first branch is connected to a third storage tank. The waste heat recovery system further includes a first level sensor configured to detect the level of the third storage tank.

[0019] In some embodiments, the waste heat recovery system further includes: a second temperature sensor configured to detect the temperature of a first mixed coolant at the junction of the coolant line and a first branch; a first control valve located at the outlet of a first reservoir, configured to control the flow rate at the outlet of the first reservoir; and a second control valve located on the first branch, configured to control the flow rate of the first branch.

[0020] In some embodiments, the cooling branch further includes a second branch, the first end of which is connected to the inlet of the heat pump, and the other end of which is connected to a second storage tank.

[0021] In some embodiments, the waste heat recovery system further includes: a third temperature sensor configured to detect the temperature of a second mixed coolant at the junction of the coolant line and the first end of the second branch; and a third control valve located on the second branch configured to control the flow rate of the second branch.

[0022] In some embodiments, the waste heat recovery system further includes: a second liquid level sensor configured to detect the liquid level in the first storage tank; and a fourth control valve located on the first bypass, configured to control the flow rate of the first bypass.

[0023] In some embodiments, the waste heat recovery system further includes a fourth temperature sensor configured to detect the temperature of the coolant at the inlet of the cooling tower.

[0024] According to a fourth aspect of the present disclosure, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions that, when executed by a processor, implement the method as described in any of the above embodiments.

[0025] According to a fifth aspect of the present disclosure, a computer program product is provided, including computer instructions, wherein when executed by a processor, the computer instructions implement the method as described in any of the above embodiments.

[0026] Other features and advantages of this disclosure will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this disclosure 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 only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic flowchart of a waste heat recovery method according to an embodiment of the present disclosure.

[0029] Figure 2 This is a schematic flowchart of a waste heat recovery method according to another embodiment of the present disclosure.

[0030] Figure 3 This is a schematic flowchart of a waste heat recovery method according to another embodiment of the present disclosure.

[0031] Figure 4 This is a schematic diagram of the structure of a waste heat recovery control device according to an embodiment of the present disclosure.

[0032] Figure 5 This is a schematic diagram of the structure of a waste heat recovery system according to an embodiment of the present disclosure. Detailed Implementation

[0033] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this disclosure or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0034] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of this disclosure.

[0035] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0036] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0037] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0038] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0039] Figure 1 This is a schematic flowchart of a waste heat recovery method according to an embodiment of the present disclosure. In some embodiments, the following waste heat recovery method is executed by a waste heat recovery control device, including steps 101-102.

[0040] In step 101, the temperature of the coolant in the first storage tank located in the waste heat recovery loop is detected. The waste heat recovery loop includes a first storage tank, a heat pump, a cooling tower, a second storage tank, and a refrigeration heat exchanger connected in series by coolant pipelines. The temperature of the coolant in the first storage tank is higher than the temperature of the coolant in the second storage tank.

[0041] For example, during startup, the refrigeration heat exchanger is started first, and the first circulation pump at the outlet of the second liquid storage tank is started simultaneously to store the coolant in the first liquid storage tank.

[0042] For example, the temperature of the coolant in the first storage tank located in the waste heat recovery loop is detected by a first temperature sensor.

[0043] In step 102, if the temperature of the coolant in the first storage tank is greater than the heat pump temperature threshold, the cooling branch is opened so as to use the coolant in the cooling branch to reduce the temperature of the coolant at the heat pump inlet.

[0044] For example, if the coolant temperature in the first storage tank is lower than the heat pump's start-up temperature, the first storage tank continues to store heat; if the coolant temperature in the first storage tank is higher than the heat pump's start-up temperature, the second circulation pump at the heat pump inlet is turned on.

[0045] Continue monitoring whether the coolant temperature in the first reservoir exceeds the heat pump temperature threshold. If the coolant temperature in the first reservoir does not exceed the heat pump temperature threshold, start the heat pump for waste heat recovery. If the coolant temperature in the first reservoir exceeds the heat pump temperature threshold, open the cooling branch to utilize the coolant in the cooling branch to lower the coolant temperature at the heat pump inlet.

[0046] Therefore, when the temperature of the coolant in the first storage tank is higher than the temperature threshold of the heat pump, the temperature of the coolant at the inlet of the heat pump is reduced through the cooling branch, so that the coolant temperature is maintained within the normal operating range allowed by the heat pump, ensuring the stable operation of the heat pump.

[0047] In some embodiments, the cooling branch includes a first branch, wherein a first end of the first branch is connected to the inlet of the heat pump, and the other end of the first branch is connected to a third liquid storage tank. Activating the cooling branch includes: detecting the liquid level in the third liquid storage tank; and activating the first branch when the liquid level in the third liquid storage tank is higher than the lower limit of the liquid level in the third liquid storage tank, so as to utilize the coolant in the third liquid storage tank to lower the coolant temperature at the inlet of the heat pump.

[0048] For example, the liquid level of the third storage tank is detected by a first liquid level sensor. If the liquid level in the third storage tank is higher than the lower limit of the liquid level in the third storage tank, the second control valve located on the first branch is opened to open the first branch.

[0049] This allows the coolant in the third storage tank to be mixed with the coolant in the first storage tank, thereby reducing the coolant temperature at the heat pump inlet, preventing the heat pump from overheating due to excessively high coolant temperature, and stabilizing the heat pump's operating conditions.

[0050] In some embodiments, after the first branch is opened, the temperature of the first mixed coolant at the connection point between the coolant pipeline and the first end of the first branch is detected. The opening degree of the control valve on the first branch and the opening degree of the control valve at the outlet of the first reservoir are adjusted according to the first mixed coolant temperature.

[0051] For example, the temperature of the first mixed coolant is detected by a second temperature sensor, and the flow rate at the outlet of the first reservoir is controlled by a first control valve located at the outlet of the first reservoir. The flow rate of the first branch is controlled by a second control valve located on the first branch.

[0052] For example, based on the temperature of the first mixed coolant, the opening of the second control valve is increased proportionally, while the opening of the first control valve is decreased proportionally at the same time.

[0053] Therefore, by adjusting the flow rate at the outlet of the first reservoir and the flow rate of the first branch according to the temperature of the first mixed coolant, the coolant ratio can be accurately matched, and the temperature of the first mixed coolant can be accurately controlled, thereby stabilizing the temperature of the first mixed coolant to the suitable operating range of the heat pump.

[0054] In some embodiments, it is detected whether the temperature of the first mixed coolant is greater than the heat pump temperature threshold. If the temperature of the first mixed coolant is greater than the heat pump temperature threshold, it is detected whether the opening of the control valve on the first branch is at its maximum opening. If the opening of the control valve on the first branch is not at its maximum opening, the opening of the control valve on the first branch is increased.

[0055] When the temperature of the first mixed coolant still exceeds the heat pump temperature threshold, the opening of the control valve on the first branch is detected. If the control valve is not at its maximum opening, the opening of the control valve is increased. This increases the supply flow to the third reservoir, increases the proportion of coolant in the third reservoir, and further reduces the temperature of the first mixed coolant, bringing the temperature of the first mixed coolant back to the safe operating range of the heat pump.

[0056] In some embodiments, the cooling branch further includes a second branch, with a first end connected to the heat pump inlet and the other end connected to a second reservoir. If the control valve on the first branch is at its maximum opening, the second branch is opened to utilize the coolant in the second reservoir to lower the coolant temperature at the heat pump inlet.

[0057] For example, if the control valve on the first branch is at its maximum opening and the temperature of the first mixed coolant is still greater than the temperature threshold of the heat pump, the third control valve on the second branch is opened to open the second branch.

[0058] Therefore, the coolant in the second storage tank can be mixed with the first mixed coolant, thereby further reducing the coolant temperature at the heat pump inlet, maintaining a stable coolant temperature, and preventing the heat pump from overheating due to excessively high coolant temperature. Through the step-by-step regulation of the second and third storage tanks, efficient utilization of thermal energy can be achieved.

[0059] In some embodiments, the temperature of the second mixed coolant at the junction of the coolant line and the first end of the second branch is detected. The opening of the control valve on the second branch and the opening of the control valve at the outlet of the first reservoir are adjusted according to the temperature of the second mixed coolant.

[0060] For example, the temperature of the second mixed coolant at the connection point between the coolant line and the first end of the second branch is detected by a third temperature sensor. The flow rate at the outlet of the first reservoir is controlled by a first control valve located at the outlet of the first reservoir. The flow rate in the second branch is controlled by a third control valve located on the second branch.

[0061] For example, based on the temperature of the second mixed coolant, the opening of the third control valve is increased proportionally, while the opening of the first control valve is decreased proportionally at the same time.

[0062] Therefore, by adjusting the flow rate at the outlet of the first reservoir and the flow rate of the second branch according to the temperature of the second mixed coolant, the heat energy can be cooled down and utilized step by step, thereby improving the efficiency of heat energy utilization.

[0063] In some embodiments, if the liquid level in the third liquid tank is not higher than the lower limit of the liquid level in the third liquid tank, the second branch is opened so as to use the coolant in the second liquid tank to reduce the coolant temperature at the inlet of the heat pump.

[0064] For example, if the liquid level in the third liquid tank is not higher than the lower limit of the liquid level in the third liquid tank, the second control valve located on the first branch will not be opened, and the third control valve located on the second branch will be opened to open the second branch, thereby using the coolant in the second liquid tank to reduce the coolant temperature at the inlet of the heat pump.

[0065] Therefore, if the liquid level in the third liquid tank is not higher than the lower limit of the liquid level in the third liquid tank, the first branch is not opened, and the second branch is opened. This allows the heat transfer path to be switched according to the temperature state of the coolant, thereby improving the adaptability of the waste heat recovery system under different operating conditions.

[0066] In some embodiments, it is detected whether the liquid level in the first reservoir is greater than a first preset value. If the liquid level in the first reservoir is greater than the first preset value, a first bypass is opened to allow the coolant in the first reservoir to flow into a third reservoir.

[0067] For example, the liquid level of the first liquid tank is detected by the second liquid level sensor. If the liquid level of the first liquid tank is greater than the first preset value, the fourth control valve located between the first liquid tank and the third liquid tank is opened to open the first bypass, thereby allowing the coolant in the first liquid tank to flow into the third liquid tank.

[0068] For example, the coolant in the first reservoir experiences temperature stratification, with the low-temperature coolant located at the bottom of the first reservoir. The first end of the fourth control valve is connected to the bottom of the first reservoir, allowing the low-temperature coolant in the first reservoir to flow preferentially into the third reservoir.

[0069] It should be noted that by opening the first bypass when the liquid level in the first liquid tank is greater than the first preset value, the coolant in the first liquid tank flows into the third liquid tank, realizing the stratified dynamic transfer of high-temperature heat energy. This gives the waste heat recovery system a good heat energy buffering capacity, effectively copes with operational fluctuations, reduces the capacity requirement of the first liquid tank, and thus reduces the initial investment.

[0070] In some embodiments, if the liquid level in the first liquid tank is not greater than a first preset value, it is detected whether the liquid level in the first liquid tank is greater than a second preset value, wherein the first preset value is greater than the second preset value. If the liquid level in the first liquid tank is greater than the second preset value, the step of detecting the temperature of the coolant in the first liquid tank located in the waste heat recovery loop is executed.

[0071] For example, if the liquid level in the first storage tank is lower than the second preset value, the first storage tank continues to store heat. If the liquid level in the first storage tank is higher than the second preset value, step 101 is executed.

[0072] This ensures that the liquid level in the first storage tank reaches the starting condition of the heat pump, and that the heat pump has sufficient coolant.

[0073] In some embodiments, it is detected whether the temperature of the coolant at the inlet of the cooling tower is greater than a preset temperature of the second storage tank. If the temperature of the coolant at the inlet of the cooling tower is greater than the preset temperature of the second storage tank, the cooling tower is turned on to reduce the temperature of the coolant at the inlet of the cooling tower.

[0074] For example, for heat pumps that cannot recover all the heat, the temperature of the coolant at the inlet of the cooling tower is detected by a fourth temperature sensor. If the temperature of the coolant at the inlet of the cooling tower is greater than the preset temperature of the second storage tank, the cooling tower is turned on, the coolant is processed and then flows to the second storage tank, until it is turned off.

[0075] Therefore, the coolant after waste heat recovery is then processed through a cooling tower according to the operating conditions, thereby ensuring the temperature stability of the second storage tank.

[0076] Figure 2 This is a schematic flowchart of a waste heat recovery method according to another embodiment of this disclosure. Figure 2 As shown, the above-mentioned opening of the cooling branch includes steps 201-213.

[0077] In step 201, it is detected whether the liquid level in the third liquid tank is higher than the lower limit of the liquid level in the third liquid tank.

[0078] If the liquid level in the third storage tank is higher than the lower limit of the liquid level in the third storage tank, proceed to step 202; otherwise, proceed to step 207.

[0079] In step 202, the first branch is opened, wherein the first end of the first branch is connected to the liquid inlet of the heat pump, and the other end of the first branch is connected to the third liquid storage tank.

[0080] In step 203, the temperature of the first mixed coolant at the connection point between the coolant pipeline and the first end of the first branch is detected.

[0081] In step 204, the opening of the control valve on the first branch and the opening of the control valve at the outlet of the first reservoir are adjusted according to the temperature of the first mixed coolant.

[0082] In step 205, it is detected whether the temperature of the first mixed coolant is greater than the heat pump temperature threshold.

[0083] If the temperature of the first mixed coolant is greater than the heat pump temperature threshold, proceed to step 206; otherwise, proceed to step 210.

[0084] In step 206, it is detected whether the opening degree of the control valve on the first branch is at its maximum.

[0085] If the control valve on the first branch is at its maximum opening, proceed to step 207; otherwise, proceed to step 212.

[0086] In step 207, the second branch is opened, wherein the first end of the second branch is connected to the liquid inlet of the heat pump, and the other end of the second branch is connected to the second liquid storage tank.

[0087] In step 208, the temperature of the second mixed coolant at the connection point between the coolant pipeline and the first end of the second branch is detected.

[0088] In step 209, the opening of the control valve on the second branch and the opening of the control valve at the outlet of the first reservoir are adjusted according to the temperature of the second mixed coolant.

[0089] In step 210, the heat pump is started to recover waste heat.

[0090] In step 211, it is detected whether the temperature of the coolant at the inlet of the cooling tower is greater than the preset temperature of the second storage tank.

[0091] If the temperature of the coolant at the inlet of the cooling tower is not greater than the preset temperature of the second storage tank, the operation shall be terminated; otherwise, proceed to step 213.

[0092] In step 212, the opening of the control valve on the first branch is increased.

[0093] In step 213, the cooling tower is started to cool the temperature of the coolant at the inlet of the cooling tower to the preset temperature of the second storage tank.

[0094] This allows for the maintenance of a stable coolant temperature, preventing overheating of the heat pump unit due to excessively high coolant temperature. The efficient utilization of thermal energy is achieved through the tiered regulation of the second and third coolant tanks.

[0095] Figure 3 This is a schematic flowchart illustrating another embodiment of a waste heat recovery method according to this disclosure. Figure 3As shown, the above-mentioned waste heat recovery method further includes the following steps, including steps 301-305.

[0096] In step 301, it is detected whether the liquid level in the first storage tank is greater than the first preset value.

[0097] If the liquid level in the first storage tank is greater than the first preset value, proceed to step 302; otherwise, proceed to step 303.

[0098] In step 302, the first bypass is opened, allowing the coolant in the first reservoir to flow into the third reservoir.

[0099] In step 303, it is detected whether the liquid level in the first storage tank is greater than the second preset value.

[0100] If the liquid level in the first storage tank is greater than the second preset value, proceed to step 304; otherwise, proceed to step 305.

[0101] In step 304, step 201 is executed.

[0102] In step 305, the operation continues and the first liquid storage tank continues to store heat.

[0103] This enables the formation of a thermal energy gradient transfer path, achieving stratified dynamic transfer of high-temperature thermal energy.

[0104] Figure 4 This is a schematic diagram of the structure of a waste heat recovery control device according to an embodiment of the present disclosure.

[0105] like Figure 4 As shown, the waste heat recovery control device 40 can be represented in the form of a general-purpose computing device. The waste heat recovery control device 40 includes a memory 41, a processor 42, and a bus 43 connecting different system components.

[0106] The memory 41 may include, for example, system memory, non-volatile storage media, etc. System memory may store, for example, an operating system, application programs, a boot loader, and other programs. System memory may include volatile storage media, such as random access memory (RAM) and / or cache memory. Non-volatile storage media may store, for example, instructions for a corresponding embodiment of at least one waste heat recovery method being executed. Non-volatile storage media include, but are not limited to, disk storage, optical storage, flash memory, etc.

[0107] The processor 42 can be implemented using a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic devices, discrete hardware components such as discrete gates or transistors. Accordingly, each module, such as the acquisition module, the calculation module, and the adjustment module, can be implemented by executing instructions in the central processing unit (CPU) running memory to perform the corresponding steps, or by implementing dedicated circuits that perform the corresponding steps.

[0108] For example, processor 42 is configured for memory-based instruction execution implementation such as Figure 1 The method involved in any of the embodiments.

[0109] Bus 43 can use any of the various bus architectures. For example, bus architectures include, but are not limited to, the Industry Standard Architecture (ISA) bus, the Micro Channel Architecture (MCA) bus, and the Peripheral Component Interconnect (PCI) bus.

[0110] The interfaces 44, 45, and 46 of the waste heat recovery control device 40, as well as the memory 41 and processor 42, can be connected via bus 43. Input / output interface 44 provides a connection interface for input / output devices such as monitors, mice, and keyboards. Network interface 45 provides a connection interface for various networked devices. Storage interface 46 provides a connection interface for external storage devices such as floppy disks, USB flash drives, and SD cards.

[0111] Various aspects of this disclosure are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus, and computer program products according to embodiments of this disclosure. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations thereof, can be implemented by computer-readable program instructions.

[0112] These computer-readable program instructions are provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable device to produce a machine, such that execution of the instructions by the processor produces means for implementing the functions specified in one or more boxes of the flowchart and / or block diagram.

[0113] These computer-readable program instructions may also be stored in a computer-readable storage medium. These instructions cause a computer to work in a particular manner to produce an article of manufacture, including instructions that implement the functions specified in one or more boxes in a flowchart and / or block diagram.

[0114] This disclosure may take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects.

[0115] This disclosure also provides a computer-readable storage medium storing computer instructions that, when executed by a processor, implement... Figure 1 The method involved in any of the embodiments.

[0116] This disclosure also provides a computer program product, including computer instructions, wherein the computer instructions, when executed by a processor, implement as follows: Figure 1 The method involved in any of the embodiments.

[0117] Figure 5 This is a schematic diagram of the structure of a waste heat recovery system according to an embodiment of the present disclosure.

[0118] like Figure 5 As shown, the waste heat recovery system includes a waste heat recovery control device 40, a waste heat recovery circuit 520, a cooling branch 530, and a first temperature sensor 541.

[0119] Waste heat recovery control device 40 Figure 4 The waste heat recovery control device shown is shown.

[0120] The waste heat recovery circuit 520 includes a first liquid storage tank 521, a heat pump 522, a cooling tower 523, a second liquid storage tank 524, and a refrigeration heat exchanger 525, which are connected in series by coolant pipelines. The coolant temperature in the first liquid storage tank 521 is higher than the coolant temperature in the second liquid storage tank 524.

[0121] The cooling branch 530 is configured to reduce the coolant temperature at the inlet of the heat pump 522 by utilizing the coolant in the cooling branch when it is in the open state according to the control of the waste heat recovery control device 40.

[0122] A first temperature sensor 541 is configured to detect the temperature of a first liquid storage tank 521 located in a waste heat recovery loop 520.

[0123] Therefore, through the waste heat recovery control device 40, waste heat recovery circuit 520, cooling branch circuit 530 and first temperature sensor 541, dynamic buffering, path switching and cascade utilization of thermal energy can be realized, thereby improving the overall operating efficiency and stability.

[0124] In some embodiments, such as Figure 5 As shown, the cooling branch 530 includes a first branch 531, wherein the first end of the first branch 531 is connected to the liquid inlet of the heat pump 522, and the other end of the first branch 531 is connected to the third liquid storage tank 526.

[0125] In some embodiments, the waste heat recovery system further includes a first liquid level sensor 551 configured to detect the liquid level of the third liquid storage tank 526.

[0126] Therefore, the liquid level of the third liquid tank 526 can be detected so that when the liquid level of the third liquid tank 526 is higher than the lower limit of the liquid level of the third liquid tank 526, the first branch 531 can be opened, thereby using the coolant in the third liquid tank 526 to reduce the coolant temperature at the inlet of the heat pump 522.

[0127] In some embodiments, the waste heat recovery system further includes: a second temperature sensor 542 configured to detect the temperature of a first mixed coolant at the junction of the coolant line and the first end of the first branch 531; a first control valve 561 located at the outlet of the first reservoir 521 configured to control the flow rate at the outlet of the first reservoir 521; and a second control valve 562 located on the first branch 531 configured to control the flow rate of the first branch 531.

[0128] Therefore, the temperature of the first mixed coolant is detected by the second temperature sensor 542, thereby adjusting the opening degree of the first control valve 561 and the second control valve 562 according to the temperature of the first mixed coolant.

[0129] In some embodiments, the cooling branch 530 further includes a second branch 532, with a first end of the second branch 532 connected to the liquid inlet of the heat pump 522 and the other end of the second branch 532 connected to the second liquid storage tank 524.

[0130] Therefore, by means of the second branch 532, the coolant temperature at the inlet of the heat pump 522 can be reduced by using the coolant in the second liquid storage tank 524.

[0131] In some embodiments, the waste heat recovery system further includes: a third temperature sensor 543 configured to detect the temperature of a second mixed coolant at the junction of the coolant line and the first end of the second branch 532; and a third control valve 563 located on the second branch 532 configured to control the flow rate of the second branch 532.

[0132] Therefore, the temperature of the second mixed coolant is detected by the third temperature sensor 543, thereby adjusting the opening degree of the first control valve 561 and the third control valve 563 according to the temperature of the second mixed coolant.

[0133] In some embodiments, the waste heat recovery system further includes: a second liquid level sensor 552 configured to detect the liquid level of the first liquid storage tank 521; and a fourth control valve 564 located on the first bypass 533 configured to control the flow rate of the first bypass 533.

[0134] Therefore, the liquid level of the first liquid storage tank 521 is detected by the second liquid level sensor 552, and the fourth control valve 564 is controlled according to the liquid level of the first liquid storage tank 521, so that when the liquid level of the first liquid storage tank 521 is greater than the first preset value, the coolant in the first liquid storage tank 521 flows into the third liquid storage tank 526.

[0135] In some embodiments, the waste heat recovery system further includes a fourth temperature sensor 544 configured to detect the temperature of the coolant at the inlet of the cooling tower 523.

[0136] Therefore, the temperature of the coolant at the inlet of the cooling tower 523 is detected by the fourth temperature sensor 544, thereby determining whether the temperature of the coolant at the inlet of the cooling tower 523 is greater than the preset temperature of the second storage tank 524.

[0137] like Figure 5 As shown, the waste heat recovery system also includes: a first circulation pump 571, a second circulation pump 572, and a third circulation pump 573.

[0138] For example, when the waste heat recovery system is running, the refrigeration heat exchanger 525 is started and the first circulation pump 571 is turned on simultaneously to store the coolant in the first storage tank 521.

[0139] For example, when the temperature of the coolant in the first storage tank 521 is higher than the starting temperature of the heat pump 522, the second circulation pump 572 is turned on.

[0140] like Figure 5 As shown, the waste heat recovery system also includes a fifth control valve 565. The fifth control valve 565 controls the coolant in the third storage tank 526 to flow into the second storage tank 524 through the cooling tower 523, and prevents the coolant flowing from the heat pump 522 from impacting the third circulation pump 573.

[0141] By implementing the above embodiments of this disclosure, the following beneficial effects can be obtained.

[0142] The dynamic coupling structure of the "first storage tank – second storage tank – third storage tank" enables the waste heat recovery system to possess excellent thermal energy buffering capacity, effectively coping with operational fluctuations and reducing the capacity requirements of the storage tanks, thereby lowering initial investment. A bidirectional temperature layer bypass control mechanism allows for dynamic switching of the heat energy path, enhancing the adaptability of the waste heat recovery system under different operating conditions and improving operational stability. A cascaded heat energy utilization control mechanism allows for step-by-step cooling and utilization of heat energy, stabilizing temperature, reducing heat loss, and improving overall heat energy utilization efficiency. The synergistic effect of these technical features significantly improves the energy supply stability, safety, and economy of the waste heat recovery system.

[0143] In some embodiments, the functional units described above may be implemented as general-purpose processors, programmable logic controllers (PLCs), digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or any suitable combination thereof for performing the functions described herein.

[0144] Those skilled in the art will understand that all or part of the steps of the above embodiments can be implemented by hardware or by a program instructing related hardware. The program can be stored in a computer-readable storage medium, such as a read-only memory, a disk, or an optical disk.

[0145] The description in this disclosure is provided for illustrative and descriptive purposes only and is not intended to be exhaustive or to limit the disclosure to its forms. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical application of this disclosure and to enable those skilled in the art to understand this disclosure and to design various embodiments with various modifications suitable for a particular purpose.

Claims

1. A waste heat recovery method, executed by a waste heat recovery control device, comprising: The temperature of the coolant in the first storage tank in the waste heat recovery loop is detected. The waste heat recovery loop includes the first storage tank, a heat pump, a cooling tower, a second storage tank and a refrigeration heat exchanger connected in series by coolant pipelines. The temperature of the coolant in the first storage tank is greater than the temperature of the coolant in the second storage tank. When the temperature of the coolant in the first storage tank is greater than the temperature threshold of the heat pump, the cooling branch is opened so as to use the coolant in the cooling branch to reduce the temperature of the coolant at the inlet of the heat pump. The cooling branch includes a first branch, the first end of the first branch is connected to the inlet of the heat pump, and the other end of the first branch is connected to the third storage tank. The activation of the cooling branch includes: Detect the liquid level in the third storage tank; When the liquid level in the third liquid tank is higher than the lower limit of the liquid level in the third liquid tank, the first branch is opened so as to use the coolant in the third liquid tank to reduce the coolant temperature at the inlet of the heat pump.

2. The waste heat recovery method according to claim 1, wherein, After activating the first branch, the following is also included: Detect the temperature of the first mixed coolant at the point where the coolant pipeline connects to the first end of the first branch; Adjust the opening of the control valve on the first branch and the opening of the control valve at the outlet of the first reservoir according to the temperature of the first mixed coolant.

3. The waste heat recovery method according to claim 2 further includes: Detect whether the temperature of the first mixed coolant is greater than the heat pump temperature threshold; If the temperature of the first mixed coolant is greater than the heat pump temperature threshold, detect whether the opening of the control valve on the first branch is at its maximum opening. If the control valve opening on the first branch is not at its maximum, increase the opening of the control valve on the first branch.

4. The waste heat recovery method according to claim 3, wherein, The cooling branch also includes a second branch, the first end of which is connected to the liquid inlet of the heat pump, and the other end of which is connected to the second liquid storage tank. The waste heat recovery method further includes: If the control valve on the first branch is at its maximum opening, the second branch is opened so that the coolant in the second storage tank can be used to lower the coolant temperature at the inlet of the heat pump.

5. The waste heat recovery method according to claim 4 further includes: Detect the temperature of the second mixed coolant at the point where the coolant pipeline connects to the first end of the second branch; Adjust the opening of the control valve on the second branch and the opening of the control valve at the outlet of the first reservoir according to the temperature of the second mixed coolant.

6. The waste heat recovery method according to claim 4 further includes: If the liquid level in the third liquid tank is not higher than the lower limit of the liquid level in the third liquid tank, the second branch is opened so as to use the coolant in the second liquid tank to reduce the coolant temperature at the inlet of the heat pump.

7. The waste heat recovery method according to claim 1 further includes: Detect whether the liquid level in the first storage tank is greater than a first preset value; If the liquid level in the first storage tank is greater than the first preset value, the first bypass is opened so that the coolant in the first storage tank flows into the third storage tank.

8. The waste heat recovery method according to claim 7 further includes: If the liquid level in the first liquid storage tank is not greater than the first preset value, detect whether the liquid level in the first liquid storage tank is greater than the second preset value, where the first preset value is greater than the second preset value; If the liquid level in the first storage tank is greater than the second preset value, the step of detecting the temperature of the coolant in the first storage tank located in the waste heat recovery circuit is executed.

9. The waste heat recovery method according to any one of claims 1-8 further comprises: Detect whether the temperature of the coolant at the inlet of the cooling tower is greater than the preset temperature of the second storage tank; If the temperature of the coolant at the inlet of the cooling tower is greater than the preset temperature of the second storage tank, the cooling tower is turned on so as to reduce the temperature of the coolant at the inlet of the cooling tower.

10. A waste heat recovery control device, comprising: The memory is configured to store instructions; A processor, coupled to a memory, configured to implement the method as described in any one of claims 1-9 based on memory-stored instruction execution.

11. A waste heat recovery system, comprising: The waste heat recovery control device as described in claim 10; The waste heat recovery circuit includes a first liquid storage tank, a heat pump, a cooling tower, a second liquid storage tank, and a refrigeration heat exchanger connected in series by a coolant pipeline, wherein the coolant temperature in the first liquid storage tank is greater than the coolant temperature in the second liquid storage tank. A cooling branch is configured to reduce the coolant temperature at the inlet of the heat pump by using coolant in the cooling branch when the waste heat recovery control device is in the open state, wherein the cooling branch includes a first branch, a first end of the first branch is connected to the inlet of the heat pump, and the other end of the first branch is connected to a third storage tank. A first temperature sensor is configured to detect the temperature of a first liquid storage tank located in the waste heat recovery loop; The first liquid level sensor is configured to detect the liquid level in the third storage tank.

12. The waste heat recovery system according to claim 11, further comprising: The second temperature sensor is configured to detect the temperature of the first mixed coolant at the point where the coolant line connects to the first end of the first branch; The first control valve located at the outlet of the first liquid storage tank is configured to control the flow rate at the outlet of the first liquid storage tank; The second control valve located on the first branch is configured to control the flow rate of the first branch.

13. The waste heat recovery system according to claim 12, wherein, The cooling branch also includes a second branch, the first end of which is connected to the liquid inlet of the heat pump, and the other end of which is connected to the second liquid storage tank.

14. The waste heat recovery system according to claim 13, further comprising: The third temperature sensor is configured to detect the temperature of the second mixed coolant at the point where the coolant line connects to the first end of the second branch; The third control valve located on the second branch is configured to control the flow rate of the second branch.

15. The waste heat recovery system according to claim 11, further comprising: The second liquid level sensor is configured to detect the liquid level in the first liquid storage tank; The fourth control valve located on the first bypass is configured to control the flow rate of the first bypass.

16. The waste heat recovery system according to any one of claims 11-15, further comprising: A fourth temperature sensor is configured to detect the temperature of the coolant at the inlet of the cooling tower.

17. A computer-readable storage medium, wherein, The computer-readable storage medium stores computer instructions that, when executed by a processor, implement the waste heat recovery method as described in any one of claims 1-9.

18. A computer program product comprising computer instructions, wherein the computer instructions, when executed by a processor, implement the waste heat recovery method as claimed in any one of claims 1-9.

Images