Device for preventing ammonia fuel from being liquefied for ammonia-diesel fuel engine, control method, equipment and medium

Abstract

The invention discloses an ammonia fuel liquefaction prevention device for an ammonia-diesel fuel engine, a control method, equipment and a medium, and relates to the field of ammonia engine design and control, the device comprises an ammonia gas suck-back unit, a processing unit and a data acquisition unit; the ammonia gas suck-back unit and the data acquisition unit are both arranged on an ammonia gas injection supply line; the ammonia gas suck-back unit and the data acquisition unit are both connected with the processing unit; the data acquisition unit is used for detecting pressure data and temperature data on an ammonia gas injection supply line; the processing unit is used for generating a control instruction based on the pressure data and the temperature data; and the ammonia gas suck-back unit is used for carrying out ammonia gas suck-back operation based on the control instruction. It can be guaranteed that gaseous ammonia does not exist in the ammonia gas supply pipeline, the service life of the nozzle is prolonged, and therefore the use cost is reduced while the reliability of the ammonia engine is improved.

Description

Technical Field

[0001] The present application relates to the field of ammonia engine design and control, and in particular to an ammonia-diesel fuel engine ammonia fuel liquefaction prevention device and a control method, equipment and medium. Background Art

[0002] The research and development of new low-carbon and zero-carbon alternative fuels and their engine technologies is imminent. The development of ammonia engines has become a more ideal route at present. However, in the current development process of ammonia engines, after the engine is shut down, ammonia is prone to liquefaction at a pressure higher than the saturated vapor pressure. The liquid ammonia obtained by liquefaction is highly corrosive and can easily damage the nozzle, resulting in reduced reliability of the ammonia engine and increased cost of use. Summary of the invention

[0003] The purpose of the present application is to provide an ammonia-diesel fuel engine to prevent ammonia fuel liquefaction device and control method, equipment and medium, which can ensure that there is no gaseous ammonia in the ammonia supply pipeline, increase the service life of the nozzle, and thereby improve the reliability of the ammonia engine while reducing the cost of use.

[0004] To achieve the above objectives, this application provides the following solutions:

[0005] In a first aspect, the present application provides an ammonia-diesel fuel engine ammonia fuel liquefaction prevention device, comprising: an ammonia backflow unit, a processing unit and a data acquisition unit;

[0006] The ammonia back-inhalation unit and the data acquisition unit are both arranged on the ammonia injection supply line; the ammonia back-inhalation unit and the data acquisition unit are both connected to the processing unit;

[0007] The data acquisition unit is used to detect the pressure data and temperature data on the ammonia injection supply line; the processing unit is used to generate a control instruction based on the pressure data and the temperature data; the ammonia back-inhalation unit is used to perform an ammonia back-inhalation operation based on the control instruction.

[0008] Optionally, the ammonia injection supply line includes: an ammonia tank, a filter, a bypass valve, a first ammonia injection supply sub-line, a second ammonia injection supply sub-line and an interface;

[0009] The ammonia tank is connected to the filter pipeline; the bypass valve is arranged on the first branch pipeline connecting the filter and the interface; the ammonia back-intake unit is arranged on the second branch pipeline connecting the filter and the interface; the first ammonia injection supply sub-circuit and the second ammonia injection supply sub-circuit are both connected to the interface pipeline.

[0010] Optionally, the first ammonia injection supply sub-circuit includes a first shut-off valve, a first pressure stabilizer and a first ammonia nozzle;

[0011] The first ammonia nozzle is connected to the interface pipeline; the first shut-off valve and the first voltage stabilizer are sequentially arranged on the connecting pipeline between the first ammonia nozzle and the interface along the direction of ammonia injection supply.

[0012] Optionally, the second ammonia injection supply sub-circuit includes a second shut-off valve, a second pressure stabilizer and a second ammonia nozzle;

[0013] The second ammonia nozzle is connected to the interface pipeline; the second shut-off valve and the second voltage stabilizer are sequentially arranged on the connecting pipeline between the second ammonia nozzle and the interface along the direction of ammonia injection supply.

[0014] Optionally, the ammonia back-inhalation unit comprises: a one-way valve, a third pressure stabilizer and a vacuum pump;

[0015] The vacuum pump, the third voltage stabilizer and the one-way valve are sequentially arranged on the second branch pipeline connecting the filter and the interface along the direction of extracting ammonia.

[0016] Optionally, the data acquisition unit includes a plurality of temperature and pressure sensors;

[0017] The plurality of temperature and pressure sensors are respectively arranged in the ammonia back-intake unit and the ammonia injection supply line.

[0018] In a second aspect, the present application provides a method for controlling a device for preventing ammonia fuel liquefaction in an ammonia-diesel fuel engine, comprising:

[0019] Acquire the running state of the ammonia engine; the running state of the ammonia engine includes a working state and a shutdown state;

[0020] When the operating state of the ammonia engine is a shutdown state, obtaining the pressure, temperature and minimum threshold value of ammonia pressure in the ammonia injection supply line;

[0021] determining a pressure threshold for liquefaction of ammonia at the temperature;

[0022] Based on the relationship between the pressure and the pressure threshold for ammonia liquefaction and the relationship between the pressure and the minimum ammonia pressure threshold, the operating state of the ammonia-diesel fuel engine's ammonia fuel liquefaction prevention device is controlled.

[0023] Optionally, controlling the working state of the ammonia-diesel fuel engine's device for preventing ammonia fuel liquefaction based on the relationship between the pressure and the pressure threshold for ammonia liquefaction and the relationship between the pressure and the minimum ammonia pressure threshold comprises:

[0024] When the pressure is greater than or equal to the pressure threshold of the ammonia liquefaction, a first control instruction is generated; the first control instruction is used to close the first shut-off valve or the second shut-off valve, and to open the ammonia back-intake unit;

[0025] When the pressure is less than or equal to the minimum ammonia pressure threshold, a second control instruction is generated; the second control instruction is used to open the first shut-off valve and the second shut-off valve, and to open the ammonia back-intake unit.

[0026] In a third aspect, the present application provides a computer device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the control method provided above.

[0027] In a fourth aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the control method provided above when executed by a processor.

[0028] According to the specific embodiments provided in this application, this application has the following technical effects:

[0029] The present application provides an ammonia-diesel fuel engine device for preventing ammonia fuel from liquefying, and a control method, equipment, and medium. By setting an ammonia backflow unit, a processing unit, and a data acquisition unit, the pressure threshold of ammonia liquefaction at the current temperature can be retrieved based on the temperature collected by the data acquisition unit, and then the ammonia backflow unit is controlled to perform an ammonia backflow operation based on the relationship between the current pressure and the pressure threshold of ammonia liquefaction and the relationship between the pressure and the minimum ammonia pressure threshold, so as to ensure that there is no gaseous ammonia in the ammonia supply pipeline, increase the service life of the nozzle, and thereby reduce the use cost while improving the reliability of the ammonia engine. In addition, by setting an ammonia backflow unit to backflow and recover ammonia in the ammonia injection supply line, the utilization rate of ammonia fuel can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1 A schematic diagram of the structure of a device for preventing ammonia fuel liquefaction in an ammonia-diesel fuel engine provided in one embodiment of the present application;

[0032] Figure 2A schematic flow chart of a control method for a liquefaction device of an ammonia-diesel fuel engine to prevent ammonia fuel from liquefying provided in one embodiment of the present application;

[0033] Figure 3 A schematic diagram of the structure of a computer device provided in one embodiment of the present application.

[0034] Description of reference numerals:

[0035] 1- ammonia tank, 2- filter, 3- ammonia back suction unit, 31- one-way valve, 32- third pressure regulator, 33- suction pump, 4- bypass valve, 5- first cut-off valve, 6- first pressure regulator, 7- first ammonia nozzle, 8- second cut-off valve, 9- second pressure regulator, 10- second ammonia nozzle. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0037] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0038] In an exemplary embodiment, the present application provides an ammonia-diesel fuel engine ammonia fuel liquefaction prevention device, comprising: an ammonia back-inhalation unit 3, a processing unit and a data acquisition unit.

[0039] The ammonia back-inhalation unit 3 and the data acquisition unit are both arranged on the ammonia injection supply line and are both connected to the processing unit.

[0040] The data acquisition unit is used to detect the pressure data and temperature data on the ammonia injection supply line. The processing unit is used to generate a control instruction based on the pressure data and temperature data. The ammonia back-inhalation unit 3 is used to perform an ammonia back-inhalation operation based on the control instruction.

[0041] In another exemplary embodiment of the present application, Figure 1 As shown, the ammonia injection supply circuit includes: an ammonia tank 1, a filter 2, a bypass valve 4, a first ammonia injection supply sub-circuit, a second ammonia injection supply sub-circuit and an interface.

[0042] The ammonia tank 1 is connected to the filter 2 by pipeline. The bypass valve 4 is arranged on the first branch pipeline connected to the filter 2 and the interface. The ammonia back-inhalation unit 3 is arranged on the second branch pipeline connected to the filter 2 and the interface. The first ammonia injection supply sub-circuit and the second ammonia injection supply sub-circuit are both connected to the interface pipeline.

[0043] Among them, Figure 1 As shown, the first ammonia injection supply sub-circuit includes a first shut-off valve 5, a first pressure regulator 6 and a first ammonia nozzle 7. The first ammonia nozzle 7 is connected to the interface pipeline. The first shut-off valve 5 and the first pressure regulator 6 are sequentially arranged on the connecting pipeline between the first ammonia nozzle 7 and the interface along the direction of ammonia injection supply.

[0044] The second ammonia injection supply sub-circuit includes a second shut-off valve 8, a second pressure regulator 9, and a second ammonia nozzle 10. The second ammonia nozzle 10 is connected to the interface pipeline. The second shut-off valve 8 and the second pressure regulator 9 are sequentially arranged on the connecting pipeline between the second ammonia nozzle 10 and the interface along the direction of ammonia injection supply.

[0045] In another exemplary embodiment of the present application, Figure 1 As shown, the ammonia back-intake unit 3 includes: a one-way valve 31, a third pressure regulator 32 and an air pump 33. The air pump 33, the third pressure regulator 32 and the one-way valve 31 are sequentially arranged on the second branch pipeline connecting the filter 2 and the interface along the direction of extracting ammonia.

[0046] In another exemplary embodiment of the present application, the data acquisition unit includes a plurality of temperature and pressure sensors, which are respectively arranged in the ammonia back-inhalation unit 3 and the ammonia injection supply line.

[0047] Among them, Figure 1 As shown, a plurality of temperature and pressure sensors are respectively arranged on the first regulator 6 , the second regulator 9 and the third regulator 32 .

[0048] In another exemplary embodiment of the present application, a vehicle-mounted ECU monitoring system may be used as a processing unit.

[0049] Based on the specific structure of the ammonia-diesel fuel engine preventing ammonia fuel liquefaction device given above in the present application, the bypass valve 4 is opened after the engine is started, and the ammonia in the ammonia tank 1 filters out impurities in the gas through the filter 2, and passes through the bypass valve 4, wherein one road of gas passes through the first cut-off valve 5 and the first voltage regulator 6 to reach the first ammonia nozzle 7 (i.e., the engine gas injection device ammonia nozzle), and the ammonia injection is carried out by the engine combustion mode judgment, and the combustion in the engine cylinder is participated in. Another road of ammonia passes through the second cut-off valve 8 and the second voltage regulator 9 to reach the second ammonia nozzle 10 (i.e., the post-processing injection device ammonia nozzle), and ammonia injection is carried out by sensor signal and logical judgment, and nitrogen oxides (NOx) in the exhaust gas are converted. After the engine is shut down, the residual ammonia in the ammonia injection supply line is recovered by the air pump 33 according to the logical judgment, so as to ensure that there is no gaseous ammonia in the ammonia injection supply line, and then liquid ammonia corrosion nozzles will not be formed. In addition, the gaseous ammonia remaining in the ammonia injection supply line is sucked back and stored in the ammonia tank 1 by the ammonia backflow unit 3, and the ammonia fuel utilization rate can also be improved.

[0050] Based on the same inventive concept, the embodiment of the present application also provides a control method for an ammonia-diesel fuel engine to prevent an ammonia fuel from liquefying. The control method comprises:

[0051] (1) Obtaining the operating state of the ammonia engine. The operating state of the ammonia engine includes a working state and a shutdown state.

[0052] (2) When the operating state of the ammonia engine is the shutdown state, the pressure, temperature and minimum threshold value of the ammonia pressure in the ammonia injection supply line are obtained.

[0053] (3) Determine the pressure threshold for liquefaction of ammonia at a certain temperature.

[0054] (4) controlling the working state of the ammonia-diesel fuel engine to prevent the ammonia fuel from liquefying based on the relationship between the pressure and the pressure threshold for ammonia liquefaction and the relationship between the pressure and the minimum ammonia pressure threshold, wherein:

[0055] When the pressure is greater than or equal to the pressure threshold of ammonia liquefaction, a first control instruction is generated. The first control instruction is used to close the first shut-off valve 5 or the second shut-off valve 8 and to open the ammonia back-intake unit 3.

[0056] When the pressure is less than or equal to the minimum ammonia pressure threshold, a second control instruction is generated. The second control instruction is used to open the first cut-off valve 5 and the second cut-off valve 8, and to open the ammonia back-inhalation unit 3.

[0057] Based on the above description, the specific implementation process of the ammonia-diesel fuel engine ammonia fuel liquefaction prevention device and control method thereof provided in the present application can be described as follows:

[0058] The engine is judged whether it is stopped by the speed and throttle signal. If the engine is stopped, the bypass valve 4 is closed, and the current pressure P1 and temperature are detected by the temperature and pressure sensor on the first stabilizer 6, and the saturated vapor pressure corresponding to the current temperature is obtained to obtain the pressure threshold P of ammonia liquefaction at the current temperature. 阈值1 If P1≥P 阈值1 , then there is a risk of ammonia liquefaction in the first ammonia injection supply sub-circuit, the second shut-off valve 8 is closed, the vacuum pump 33 starts to work, and the ammonia in the first ammonia injection supply sub-circuit is sucked back. The sucked back ammonia is pressurized and stabilized by the third regulator 32, and then stored in the ammonia tank 1 through the one-way valve 31. Determine P1≤P min , if P1≤P min , indicating that the ammonia in the first ammonia injection supply sub-circuit is basically exhausted, and then the first shut-off valve 5 and the second shut-off valve 8 are opened, and the vacuum pump 33 again sucks back the ammonia in the first ammonia injection supply sub-circuit and the second ammonia injection supply sub-circuit, and after being pressurized and stabilized by the third regulator 32, it is stored in the ammonia tank 1 through the one-way valve 31. By sucking back the ammonia in the two ammonia injection supply sub-circuits at the same time, the gaseous ammonia can be further sucked clean. When P1≤P min And P2≤P min When the ammonia backflow is completed, otherwise it returns to the previous logic judgment. min The pressure threshold indicating that the ammonia gas has been completely pumped out, and P2 indicates the current pressure detected by the temperature and pressure sensor on the second pressurizer 9.

[0059] Similarly, if P2 ≥ P 阈值2 , then the second ammonia injection supply sub-circuit has the risk of ammonia liquefaction, and the above P1≥P 阈值1 The same logic control. The entire control process is as follows Figure 2 shown.

[0060] In summary, the present application adds an ammonia back-intake unit to the ammonia injection supply line to prevent liquid ammonia from damaging the nozzle, and recovers and stores the residual ammonia in the ammonia tank, thereby improving the utilization rate of the ammonia fuel.

[0061] The present application can ensure that the ammonia in the ammonia injection supply line is cleanly back-sucked by performing relevant logical judgment and strategy control of ammonia back-sucking, and prevent the formation of liquid ammonia in the two pipelines of engine fuel supply and post-treatment reductant supply, thereby improving the maturity of ammonia-diesel engine technology.

[0062] In addition, the ammonia-diesel fuel engine ammonia fuel liquefaction prevention device and control method provided in the present application are not limited to application in ammonia-diesel dual-fuel engines, but can also be applied to engines in the form of ammonia ether, ammonia diesel, methanol diesel, ammonia hydrogen, etc.

[0063] In an exemplary embodiment, a computer device is provided. The computer device may be a server or a terminal. The internal structure diagram thereof may be as follows: Figure 3 As shown. The computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. Among them, the processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store control data of the ammonia-diesel fuel engine to prevent ammonia fuel liquefaction device. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, the control method provided above is implemented.

[0064] Those skilled in the art will understand that Figure 3 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components. In an exemplary embodiment, a computer device is provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above-mentioned method embodiments when executing the computer program.

[0065] In an exemplary embodiment, a computer-readable storage medium is provided, storing a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0066] In an exemplary embodiment, a computer program product is provided, including a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0067] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0068] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM may be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0069] The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. The non-relational database may include a distributed database based on blockchain, etc., but is not limited thereto. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but is not limited thereto.

[0070] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0071] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. An ammonia-diesel fuel engine ammonia fuel liquefaction prevention device, characterized in that: The device for preventing ammonia fuel liquefaction in an ammonia-diesel fuel engine comprises: an ammonia backflow unit, a processing unit and a data acquisition unit; The ammonia back-inhalation unit and the data acquisition unit are both arranged on the ammonia injection supply line; the ammonia back-inhalation unit and the data acquisition unit are both connected to the processing unit; The data acquisition unit is used to detect the pressure data and temperature data on the ammonia injection supply line; the processing unit is used to generate a control instruction based on the pressure data and the temperature data; the ammonia back-inhalation unit is used to perform an ammonia back-inhalation operation based on the control instruction.

2. The device for preventing ammonia fuel liquefaction in an ammonia-diesel fuel engine according to claim 1, characterized in that: The ammonia injection supply line includes: an ammonia tank, a filter, a bypass valve, a first ammonia injection supply sub-line, a second ammonia injection supply sub-line and an interface; The ammonia tank is connected to the filter pipeline; the bypass valve is arranged on the first branch pipeline connecting the filter and the interface; the ammonia back-intake unit is arranged on the second branch pipeline connecting the filter and the interface; the first ammonia injection supply sub-circuit and the second ammonia injection supply sub-circuit are both connected to the interface pipeline.

3. The device for preventing ammonia fuel liquefaction in an ammonia-diesel fuel engine according to claim 2, characterized in that: The first ammonia injection supply sub-circuit comprises a first shut-off valve, a first pressure stabilizer and a first ammonia nozzle; The first ammonia nozzle is connected to the interface pipeline; the first shut-off valve and the first voltage stabilizer are sequentially arranged on the connecting pipeline between the first ammonia nozzle and the interface along the direction of ammonia injection supply.

4. The device for preventing ammonia fuel liquefaction in an ammonia-diesel fuel engine according to claim 2, characterized in that: The second ammonia injection supply sub-circuit includes a second shut-off valve, a second pressure stabilizer and a second ammonia nozzle; The second ammonia nozzle is connected to the interface pipeline; the second shut-off valve and the second voltage stabilizer are sequentially arranged on the connecting pipeline between the second ammonia nozzle and the interface along the direction of ammonia injection supply.

5. The device for preventing ammonia fuel liquefaction of an ammonia-diesel fuel engine according to claim 2, characterized in that: The ammonia back-inhalation unit comprises: a one-way valve, a third pressure stabilizer and a vacuum pump; The vacuum pump, the third voltage stabilizer and the one-way valve are sequentially arranged on the second branch pipeline connecting the filter and the interface along the direction of extracting ammonia.

6. The device for preventing ammonia fuel liquefaction in an ammonia-diesel fuel engine according to claim 1, characterized in that: The data acquisition unit includes a plurality of temperature and pressure sensors; The plurality of temperature and pressure sensors are respectively arranged in the ammonia back-intake unit and the ammonia injection supply line.

7. A control method for preventing an ammonia fuel liquefaction device of an ammonia-diesel fuel engine, characterized in that: The control method comprises: Acquire the running state of the ammonia engine; the running state of the ammonia engine includes a working state and a shutdown state; When the operating state of the ammonia engine is a shutdown state, obtaining the pressure, temperature and minimum threshold value of ammonia pressure in the ammonia injection supply line; determining a pressure threshold for liquefaction of ammonia at the temperature; Based on the relationship between the pressure and the pressure threshold for ammonia liquefaction and the relationship between the pressure and the minimum ammonia pressure threshold, the operating state of the ammonia-diesel fuel engine's ammonia fuel liquefaction prevention device is controlled.

8. The control method for preventing ammonia fuel liquefaction of an ammonia-diesel fuel engine according to claim 7, characterized in that: Based on the relationship between the pressure and the pressure threshold for ammonia liquefaction and the relationship between the pressure and the minimum ammonia pressure threshold, the working state of the ammonia-diesel fuel engine device for preventing ammonia fuel liquefaction is controlled, including: When the pressure is greater than or equal to the pressure threshold of the ammonia liquefaction, a first control instruction is generated; the first control instruction is used to close the first shut-off valve or the second shut-off valve, and to open the ammonia back-intake unit; When the pressure is less than or equal to the minimum ammonia pressure threshold, a second control instruction is generated; the second control instruction is used to open the first shut-off valve and the second shut-off valve, and to open the ammonia back-intake unit.

9. A computer device comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the control method described in any one of claims 7 to 8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the control method described in any one of claims 7 to 8 is implemented.

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