Gas cylinder heating and pressurizing and LNG cold energy utilization system and control method thereof

Abstract

The invention discloses a gas cylinder heating and pressurizing and LNG cold energy utilization system and a control method thereof.The system comprises an LNG storage tank, a cooler, a gas supply mechanism and a booster pump, the cooler comprises a cooling shell, a first cooling pipe and a second cooling pipe, and the first cooling pipe and the second cooling pipe are arranged in the cooling shell; the gas supply mechanism comprises a vaporizer and a buffer tank, and a third heat dissipation pipe, a fourth heat dissipation pipe and a fifth heat dissipation pipe are arranged in the vaporizer. The system has the beneficial effects that by arranging the heat exchange channel and the booster pump, the temperature of low-temperature LNG in the LNG storage tank can be effectively increased, and then the gasification process of the low-temperature LNG is accelerated. The pressure in the LNG storage tank is always kept at the LNG saturation pressure, so that the pressure in the LNG storage tank can be always kept stable even if a vehicle runs; and meanwhile, the system provides cold energy for the refrigeration air conditioner through the second heat dissipation pipe in the cooler, cold energy recycling is achieved, and the energy utilization efficiency of the whole system is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of LNG vehicle gas supply systems, and in particular to a gas cylinder heating and pressurizing and LNG cold energy utilization system and a control method thereof. Background Art

[0002] LNG (liquefied natural gas) vehicles refer to cars or transportation vehicles that use liquefied natural gas as fuel. Such vehicles store and supply fuel through a special LNG supply system to ensure the normal operation of their power systems. As a clean and efficient energy source, LNG has received extensive attention and application in the field of transportation in recent years, especially in heavy-duty commercial vehicles and long-distance transport vehicles, where its economy and environmental protection are particularly prominent.

[0003] In the gas supply system of LNG vehicles, the stability of the pressure in the LNG bottle is crucial to ensure the stable output of fuel. As a container for storing fuel, the internal pressure of the LNG bottle directly affects the fuel supply efficiency and the operating stability of the vehicle. Therefore, how to maintain the stability of the pressure in the LNG bottle has become an urgent problem to be solved.

[0004] At present, there are two main pressurization schemes used in LNG vehicle gas supply systems: natural pressurization and buffer tank integrated pump pressurization. The natural pressurization scheme uses the pressure difference generated by the gasification of LNG itself for pressurization. Although this scheme is simple and low-cost, it has the problem of slow pressurization and is difficult to meet the fuel needs of vehicles under high load or emergency conditions.

[0005] In contrast, the buffer tank integrated pump boosting solution uses electric pumps and other equipment to increase the pressure in the LNG bottle, which is faster and can better meet the vehicle's fuel needs. However, this solution also faces some challenges during vehicle driving. Since the LNG liquid in the LNG bottle will shake as the vehicle drives, this will cause the pressure in the bottle to fluctuate, which in turn affects the stable supply of fuel.

[0006] In addition, both natural supercharging and buffer tank integrated pump supercharging solutions face the problem of cold energy utilization. During the natural supercharging process, the cold energy generated by LNG gasification is mainly dissipated into the air through the finned tubes, resulting in energy waste. Although the buffer tank integrated electric pump supercharging solution uses part of the cold energy for engine cooling and heat dissipation, after the engine cooling demand is met, the remaining cold energy still cannot be effectively utilized by the system. Especially in summer, when the vehicle needs additional air conditioning cooling, if this part of the cold energy can be reasonably utilized, it will be able to further improve the energy efficiency of LNG vehicles.

[0007] In summary, LNG vehicles and their gas supply systems face many challenges in their development, especially in terms of pressure stability in LNG bottles and cold energy utilization. Summary of the invention

[0008] The purpose of the present invention is to overcome the above technical deficiencies and propose a gas cylinder heating and pressurizing and LNG cold energy utilization system to solve the technical problems in the prior art that the gas supply system of LNG vehicles is difficult to ensure the stability of the pressure in the LNG bottle when the vehicle is driving and the LNG cold energy utilization is insufficient.

[0009] In order to achieve the above technical objectives, the present invention adopts the following technical solutions: The present invention provides a gas cylinder temperature increasing and pressurizing system and LNG cold energy utilization system, comprising: LNG storage tank, the inner wall of which is provided with a heat exchange channel; A cold take-off device, comprising a cold take-off housing and a first heat dissipation pipe and a second heat dissipation pipe arranged in the cold take-off housing, wherein the cold take-off housing is connected to one end of the heat exchange channel, one end of the first heat dissipation pipe is connected to the LNG storage tank, and the second heat dissipation pipe is used to supplement cold for the refrigeration air conditioner; an air supply mechanism, comprising a vaporizer and a buffer tank, wherein the vaporizer is provided with a third heat dissipation pipe, a fourth heat dissipation pipe and a fifth heat dissipation pipe, wherein both ends of the third heat dissipation pipe are respectively connected to the inlet of the LNG storage tank and the buffer tank, both ends of the fourth heat dissipation pipe are respectively connected to the other end of the first heat dissipation pipe and the inlet of the buffer tank, and one end of the fifth heat dissipation pipe is connected to the other end of the heat exchange channel; and, A booster pump, an inlet of which is connected to the cooling housing, and an outlet of which is connected to the other end of the fifth heat dissipation pipe.

[0010] In some embodiments, a heating liquid inlet and a heating liquid outlet connected to both ends of the heat exchange channel are provided on the side wall of the LNG storage tank.

[0011] In some embodiments, the cooling shell contains a heat exchange medium, and a cooling inlet and a cooling outlet are respectively provided on both sides of the cooling shell. The cooling device also includes a first connecting pipe and a second connecting pipe, one end of the first connecting pipe is connected to the heating liquid outlet, the other end of the first connecting pipe is connected to the cooling inlet, one end of the second connecting pipe is connected to the cooling outlet, and the other end of the second connecting pipe is connected to the inlet of the boosting pump.

[0012] In some embodiments, the vaporizer further includes a third connecting pipe, one end of the third connecting pipe is connected to one end of the fifth heat dissipation pipe, and the other end of the third connecting pipe is connected to the heating liquid inlet.

[0013] In some embodiments, the cooler also includes a fourth connecting pipe and a fifth connecting pipe, one end of the fourth connecting pipe is connected to the outlet of the LNG storage tank, the other end of the fourth connecting pipe is connected to one end of the first heat dissipation pipe, one end of the fifth connecting pipe is connected to the other end of the first heat dissipation pipe, and the other end of the fifth connecting pipe is connected to one end of the fourth heat dissipation pipe.

[0014] In some embodiments, the vaporizer also includes a sixth connecting pipe and a seventh connecting pipe, one end of the sixth connecting pipe is connected to the outlet of the LNG storage tank, the other end of the sixth connecting pipe is connected to one end of the third heat dissipation pipe, one end of the seventh connecting pipe is connected to the other end of the third heat dissipation pipe, the other end of the seventh connecting pipe is connected to the inlet of the buffer tank, a first control valve is provided on the seventh connecting pipe, and the outlet of the buffer tank is used to connect to the air intake end of the engine.

[0015] In some embodiments, the vaporizer also includes an eighth connecting pipe and a ninth connecting pipe, one end of the eighth connecting pipe is connected to the outlet of the boost pump, the other end of the eighth connecting pipe is connected to one end of the fifth heat dissipation pipe, one end of the ninth connecting pipe is connected to the other end of the fifth heat dissipation pipe, the other end of the ninth connecting pipe is connected to the inlet of the buffer tank, and a second control valve is provided on the ninth connecting pipe.

[0016] In some embodiments, the gas cylinder heating and pressurizing and LNG cold energy utilization system also includes a heat exchange mechanism, which includes a circulating pump, a plate exchanger, a cold core and a temperature sensor. The inlet of the circulating pump is connected to one end of the second heat dissipation pipe, and the outlet of the circulating pump is connected to one end of the plate exchanger. The plate exchanger is connected to the refrigeration air conditioner and is used to provide cold energy for the refrigeration air conditioner. The other end of the plate exchanger is connected to one end of the cold core, and the other end of the cold core is connected to the other end of the second heat dissipation pipe. The temperature sensor is used to detect the temperature of the medium in the heat exchange mechanism.

[0017] In some embodiments, the plate exchanger is also connected to a heating air conditioner and is used to receive heat generated by the heating air conditioner.

[0018] The present invention also provides a control method for a gas cylinder temperature and pressure increase and LNG cold energy utilization system, comprising: S1. When the pressure in the LNG storage tank is lower than the LNG saturation pressure, the booster pump works to extract the medium in the cold shell into the fifth heat dissipation pipe in the vaporizer. The medium is vaporized in the fifth heat dissipation pipe, absorbs heat, and then flows to the heat exchange channel of the LNG storage tank to exchange heat with the low-temperature LNG in the LNG storage tank, thereby gradually transferring heat to the LNG liquid in the LNG storage tank, thereby heating the LNG liquid and increasing the pressure in the LNG storage tank. After reaching the LNG saturation pressure, the booster pump stops working; S2. When the vehicle is powered on and refrigeration and air conditioning are not needed, the LNG liquid in the LNG storage tank enters the third heat dissipation pipe in the vaporizer and, after being vaporized, enters the buffer tank and is then discharged from the buffer tank for use by the engine; S3. When the vehicle is powered on and refrigeration and air conditioning is needed, the LNG liquid in the LNG storage tank first enters the first heat dissipation pipe in the refrigeration shell, and exchanges heat with the medium in the refrigeration shell to reduce the temperature of the medium in the refrigeration shell, and then flows to the fourth heat dissipation pipe in the vaporizer for vaporization, and then enters the buffer tank, and then is discharged from the buffer tank for use by the engine; at the same time, the second heat dissipation pipe in the refrigeration device is used to supplement the cooling for the refrigeration and air conditioning.

[0019] Compared with the prior art, the beneficial effects of the gas cylinder heating and pressurizing and LNG cold energy utilization system provided by the present invention are: by setting a heat exchange channel and a booster pump, the system can effectively heat up the low-temperature LNG in the LNG storage tank, thereby accelerating its gasification process. The operation of the booster pump can be automatically adjusted according to the pressure in the LNG storage tank. When the pressure is lower than the LNG saturation pressure, the booster pump starts to work and increases the pressure in the tank, so that the pressure in the LNG storage tank is always maintained at the LNG saturation pressure. In this way, even when the vehicle is driving, the pressure in the LNG storage tank can always remain stable; at the same time, the system provides cold energy for the refrigeration and air conditioning through the second heat dissipation pipe in the cooler, thereby realizing the recycling of cold energy. This not only reduces the energy consumption of the refrigeration and air conditioning, but also improves the energy utilization efficiency of the entire system. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of a gas cylinder heating and pressurizing and LNG cold energy utilization system provided by one embodiment of the present invention; Figure 2 yes Figure 1 The structural diagram of the LNG storage tank; Figure 3 yes Figure 1 Schematic diagram of the control flow of the gas cylinder heating and pressurization and LNG cold energy utilization system; Explanation of the reference numerals: 1-LNG storage tank, 11-heat exchange channel, 12-heating liquid inlet, 13-heating liquid outlet, 2-cooling device, 21-cooling shell, 22-first heat dissipation pipe, 23-second heat dissipation pipe, 24-first connecting pipe, 25-second connecting pipe, 26-fourth connecting pipe, 27-fifth connecting pipe, 3-gas supply mechanism, 31-vaporizer, 311-third heat dissipation pipe, 312-fourth heat dissipation pipe, 313-fifth heat dissipation pipe, 314-third connecting pipe, 315-sixth connecting pipe, 316-seventh connecting pipe, 317-eighth connecting pipe, 318-ninth connecting pipe, 32-buffer tank, 4-boosting pump, 5-refrigeration air conditioner, 6-heat exchange mechanism, 61-circulation pump, 62-plate exchange, 63-cold core, 7-heating air conditioner, V1-first control valve, V2-second control valve, T3-temperature sensor. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0022] In order to solve the technical problems in the prior art that the gas supply system of LNG vehicles is difficult to ensure the stability of the pressure in the LNG bottle when the vehicle is in motion and the insufficient utilization of LNG cold energy, the present invention provides a gas cylinder heating and pressurizing and LNG cold energy utilization system, which can ensure the stability of the pressure in the LNG bottle when the vehicle is in motion and can fully utilize the LNG cold energy.

[0023] See also Figure 1-Figure 3 , Figure 1 This is a structural schematic diagram of a gas cylinder heating and pressurizing and LNG cold energy utilization system in one embodiment of the present invention. The gas cylinder heating and pressurizing and LNG cold energy utilization system includes an LNG storage tank 1, a cooler 2, a gas supply mechanism 3 and a booster pump 4.

[0024] The inner wall of the LNG storage tank 1 is provided with a heat exchange channel 11 ; it should be understood that the LNG storage tank 1 is provided with a pressure detection unit, which can detect the pressure inside the LNG storage tank 1 .

[0025] The cold take-out device 2 includes a cold take-out housing 21 and a first heat dissipation pipe 22 and a second heat dissipation pipe 23 disposed in the cold take-out housing 21. The cold take-out housing 21 is connected to one end of the heat exchange channel 11, one end of the first heat dissipation pipe 22 is connected to the LNG storage tank 1, and the second heat dissipation pipe 23 is used to supplement cold for the refrigeration air conditioner 5; The gas supply mechanism 3 includes a vaporizer 31 and a buffer tank 32, and the vaporizer 31 is provided with a third heat dissipation pipe 311, a fourth heat dissipation pipe 312 and a fifth heat dissipation pipe 313, both ends of the third heat dissipation pipe 311 are respectively connected to the inlet of the LNG storage tank 1 and the buffer tank 32, both ends of the fourth heat dissipation pipe 312 are respectively connected to the other end of the first heat dissipation pipe 22 and the inlet of the buffer tank 32, and one end of the fifth heat dissipation pipe 313 is connected to the other end of the heat exchange channel 11; it should be understood that when the engine is working, the medium in the vaporizer 31 exchanges heat with the engine, thereby cooling the engine. Conversely, the heat generated by the engine can also heat the medium in the vaporizer 31, so that the medium in the vaporizer 31 is heated.

[0026] The inlet of the boost pump 4 is communicated with the cooling housing 21 , and the outlet thereof is communicated with the other end of the fifth heat dissipation pipe 313 .

[0027] When in use, when the pressure in the LNG storage tank is lower than the set pressure P, the booster pump 4 starts to work and extracts the medium in the cold housing into the fifth heat dissipation pipe 313 in the vaporizer 31. The medium is vaporized in the fifth heat dissipation pipe 313, absorbs heat, and then flows into the heat exchange channel 11 of the LNG storage tank to exchange heat with the low-temperature LNG in the LNG storage tank, thereby gradually transferring heat to the LNG liquid in the LNG storage tank, causing the LNG liquid to heat up and the pressure in the LNG storage tank to increase. When the pressure reaches the LNG saturation pressure, the booster pump 4 stops working; when the vehicle is powered on, if the refrigeration air conditioner 5 is not needed, the LNG liquid in the LNG storage tank directly enters the third heat dissipation pipe 311 in the vaporizer 31 for vaporization, and then enters the buffer tank 32 for buffering and voltage stabilization, and finally is discharged from the buffer tank 32 for use by the engine; when the vehicle is powered on, if the refrigeration air conditioner 5 is needed, the LNG liquid in the LNG storage tank first enters the first heat dissipation pipe 22 in the cold taker 2, exchanges heat with the medium in the cold housing, and reduces the temperature of the medium in the cold housing. Subsequently, the medium enters the fourth heat dissipation pipe 312 in the vaporizer 31 for gasification, then enters the buffer tank 32 for buffering and pressure stabilization, and finally is discharged from the buffer tank 32 for use by the engine. At the same time, the second heat dissipation pipe 23 in the cooler 2 is used to supplement the cooling for the refrigeration air conditioner 5, realizing the recycling of cold energy.

[0028] The technical solution provided by the present invention can effectively heat up the low-temperature LNG in the LNG storage tank by setting a heat exchange channel and a booster pump, thereby accelerating its gasification process. The operation of the booster pump can be automatically adjusted according to the pressure in the LNG storage tank. When the pressure is lower than the LNG saturation pressure, the booster pump starts to work and increases the pressure in the tank, so that the pressure in the LNG storage tank is always maintained at the LNG saturation pressure. In this way, even when the vehicle is driving, the pressure in the LNG storage tank can always remain stable; at the same time, the system provides cold energy for the refrigeration and air conditioning through the second heat dissipation pipe in the cooler, thereby realizing the recycling of cold energy. This not only reduces the energy consumption of the refrigeration and air conditioning, but also improves the energy utilization efficiency of the entire system.

[0029] In one embodiment, see Figure 1 and Figure 2 A heating liquid inlet 12 and a heating liquid outlet 13 connected to both ends of the heat exchange channel 11 are provided on the side wall of the LNG storage tank 1 .

[0030] In one embodiment, see Figure 1 and Figure 2 The cooling shell 21 of the cooler 2 is filled with heat exchange medium, and a cooling inlet and a cooling outlet are respectively opened on both sides of the cooling shell 21. The cooler 2 also includes a first connecting pipe 24 and a second connecting pipe 25. One end of the first connecting pipe 24 is connected to the heating liquid outlet 13, and the other end of the first connecting pipe 24 is connected to the cooling inlet. One end of the second connecting pipe 25 is connected to the cooling outlet, and the other end of the second connecting pipe 25 is connected to the inlet of the booster pump 4.

[0031] In one embodiment, see Figure 1 and Figure 2 The vaporizer 31 of the air supply mechanism 3 further includes a third connecting pipe 314 , one end of the third connecting pipe 314 is connected to one end of the fifth heat dissipation pipe 313 , and the other end of the third connecting pipe 314 is connected to the heating liquid inlet 12 .

[0032] In one embodiment, see Figure 1 and Figure 2 The cooler 2 also includes a fourth connecting pipe 26 and a fifth connecting pipe 27. One end of the fourth connecting pipe 26 is connected to the outlet of the LNG storage tank 1, and the other end of the fourth connecting pipe 26 is connected to one end of the first heat dissipation pipe 22. One end of the fifth connecting pipe 27 is connected to the other end of the first heat dissipation pipe 22, and the other end of the fifth connecting pipe 27 is connected to one end of the fourth heat dissipation pipe 312.

[0033] In one embodiment, see Figure 1 and Figure 2The vaporizer 31 of the gas supply mechanism 3 also includes a sixth connecting pipe 315 and a seventh connecting pipe 316. One end of the sixth connecting pipe 315 is connected to the outlet of the LNG storage tank 1, and the other end of the sixth connecting pipe 315 is connected to one end of the third heat dissipation pipe 311. One end of the seventh connecting pipe 316 is connected to the other end of the third heat dissipation pipe 311, and the other end of the seventh connecting pipe 316 is connected to the inlet of the buffer tank 32. The seventh connecting pipe 316 is provided with a first control valve V1, and the outlet of the buffer tank 32 is used to be connected to the air intake end of the engine.

[0034] In one embodiment, see Figure 1 and Figure 2 The vaporizer 31 of the air supply mechanism 3 also includes an eighth connecting pipe 317 and a ninth connecting pipe 318. One end of the eighth connecting pipe 317 is connected to the outlet of the boost pump 4, the other end of the eighth connecting pipe 317 is connected to one end of the fifth heat dissipation pipe 313, one end of the ninth connecting pipe 318 is connected to the other end of the fifth heat dissipation pipe 313, the other end of the ninth connecting pipe 318 is connected to the inlet of the buffer tank 32, and the second control valve V2 is arranged on the ninth connecting pipe 318.

[0035] In one embodiment, see Figure 1 and Figure 2 The gas cylinder temperature increasing and pressurizing and LNG cold energy utilization system also includes a heat exchange mechanism 6, which includes a circulation pump 61, a plate exchanger 62, a cold core 63 and a temperature sensor T3. The inlet of the circulation pump 61 is connected to one end of the second heat dissipation pipe 23, and the outlet of the circulation pump 61 is connected to one end of the plate exchanger 62. The plate exchanger 62 is connected to the refrigeration air conditioner 5 and is used to provide cold energy for the refrigeration air conditioner 5. The other end of the plate exchanger 62 is connected to one end of the cold core 63, and the other end of the cold core 63 is connected to the other end of the second heat dissipation pipe 23. The temperature sensor T3 is used to detect the temperature of the medium in the heat exchange mechanism 6.

[0036] In one embodiment, see Figure 1 and Figure 2 The plate exchanger 62 is also connected to the heating air conditioner 7 and is used to receive the heat generated by the heating air conditioner 7. When the heating air conditioner 7 is needed in winter, the heating air conditioner 7 transfers the generated heat to the plate exchanger 62, and then under the action of the circulation pump 61, the heat is heated to the second heat dissipation pipe 23 in the cold storage device 2 through the plate exchanger 62, thereby heating the medium in the cold storage device 2. The heated medium then enters the heat exchange channel 11 of the LNG storage tank 1 through the booster pump 4 and the fifth heat dissipation pipe 313, and heats the LNG liquid in the LNG storage tank 1, thereby achieving the saturation pressure of the LNG in the bottle.

[0037] In one of the embodiments, the gas cylinder heating and pressurizing and LNG cold energy utilization system also includes a controller, which is electrically connected to the LNG storage tank, the boosting pump, the first control valve and the second control valve for achieving control.

[0038] The present invention also provides a control method for a gas cylinder temperature and pressure increase and LNG cold energy utilization system, comprising: S1. When the pressure in the LNG storage tank 1 is lower than the LNG saturation pressure, the booster pump 4 works to extract the medium in the cooling shell 21 of the cooler 2 to the fifth heat dissipation pipe 313 in the vaporizer 31 of the gas supply mechanism 3. The medium is vaporized in the fifth heat dissipation pipe 313, and then flows to the heat exchange channel 11 of the LNG storage tank 1 after absorbing heat, and conducts heat exchange with the low-temperature LNG in the LNG storage tank 1, thereby gradually transferring heat to the LNG liquid in the LNG storage tank 1, so that the LNG liquid is heated up, and the pressure in the LNG storage tank 1 is increased. After reaching the LNG set saturation pressure Pb, the booster pump 4 stops working; S2, when the vehicle is powered on and the refrigeration and air conditioning 5 is not needed, the first control valve V1 is opened and the second control valve V2 is closed, and the LNG liquid in the LNG storage tank 1 enters the third heat dissipation pipe 311 in the vaporizer 31 of the gas supply mechanism 3, and after being gasified, enters the buffer tank 32 through the first control valve V1, and is then discharged from the buffer tank 32 for use by the engine; S3. When the vehicle is powered on and the refrigeration air conditioner 5 is needed, the first control valve V1 is closed and the second control valve V2 is opened. The LNG liquid in the LNG storage tank 1 first enters the first heat dissipation pipe 22 of the cooler 2 and exchanges heat with the medium in the cool shell 21 of the cooler 2, so that the temperature of the medium in the cool shell 21 is reduced. The LNG liquid then flows to the fourth heat dissipation pipe 312 in the vaporizer 31 of the gas supply mechanism 3 for vaporization, and then enters the buffer tank 32 through the second control valve V2, and is then discharged from the buffer tank 32 for use by the engine. At the same time, the second heat dissipation pipe 23 in the cooler 2 is used to supplement the cooling for the refrigeration air conditioner 5. Specifically, the circulation pump 61 drives the heat medium to circulate in the second heat dissipation pipe 23, the plate exchanger 62 and the cold core 63, so that the cold energy of the medium in the cold collection shell 21 of the cold collection device 2 is transferred to the air-conditioning refrigeration system via the plate exchanger 62. When the cold energy of LNG is insufficient, the plate exchanger 62 is further cooled by the refrigeration air conditioner 5 according to the temperature setting of T3, thereby realizing energy-saving use of air conditioning. It is estimated that the use of air conditioning in summer can reduce the fuel consumption of the whole vehicle by about 3% to 5%.

[0039] Please refer to Figure 3 , the control strategy of the above principle is described as follows: When the vehicle is powered on: (the following controls are performed simultaneously without any particular order) (1) First, the liquid level sensor LG in the LNG storage tank, the gas cylinder pressure sensor P1, and the buffer tank pressure sensor P2 perform status detection and measurement. The controller converts each measurement value into a digital signal and sends it to the vehicle through a message to display the corresponding liquid level and pressure, as well as the corresponding instrument display and alarm strategy; (2) The booster pump is powered on. When the following conditions are met at the same time: ① the monitoring temperature is between -t1 and t2℃, ② the voltage is between (U1 and U2)V, ③ the current is ≤i1A, and ④ the controller receives the pressure in the gas cylinder ≤Pa Mpa, the booster pump starts working. Otherwise, the booster pump stops working. If the continuous boosting time exceeds t3 and the gas cylinder pressure still does not reach the pressure Pb, the booster pump enters the protection state and stops working for t4 minutes. After that, the booster pump restarts and enters the next judgment to repeat the above pump start process judgment. (3) When the ambient temperature is greater than a certain temperature t5, the solenoid valve V2 opens and V1 closes, and the discharged LNG is cooled continuously through the cooler for use by the air conditioning system. Conversely, when the temperature is less than a certain temperature t5, the solenoid valve V2 closes and V1 opens; when the cooler temperature is ≥ t6, the solenoid valve V2 opens and V1 closes; when the cooler temperature is continued to be ≤ -t6 °C, the solenoid valve V2 closes and V1 opens. The opening and closing of the solenoid valves V1 and V2 are determined according to the ambient temperature and the medium temperature cycle in the cooler, so that the cold energy of the engine burning LNG is continuously used for refrigeration and air conditioning as needed.

[0040] The technical solution provided by the present invention can effectively heat up the low-temperature LNG in the LNG storage tank by setting a heat exchange channel and a booster pump, thereby accelerating its gasification process. The operation of the booster pump can be automatically adjusted according to the pressure in the LNG storage tank. When the pressure is lower than the LNG saturation pressure, the booster pump starts to work and increases the pressure in the tank, so that the pressure in the LNG storage tank is always maintained at the LNG saturation pressure. In this way, even when the vehicle is driving, the pressure in the LNG storage tank can always remain stable; at the same time, the system provides cold energy for the refrigeration and air conditioning through the second heat dissipation pipe in the cooler, thereby realizing the recycling of cold energy. This not only reduces the energy consumption of the refrigeration and air conditioning, but also improves the energy utilization efficiency of the entire system.

[0041] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A gas cylinder heating and pressurizing system and LNG cold energy utilization system, characterized in that: include: LNG storage tank, the inner wall of which is provided with a heat exchange channel; A cold take-off device, comprising a cold take-off housing and a first heat dissipation pipe and a second heat dissipation pipe arranged in the cold take-off housing, wherein the cold take-off housing is connected to one end of the heat exchange channel, one end of the first heat dissipation pipe is connected to the LNG storage tank, and the second heat dissipation pipe is used to supplement cold for the refrigeration air conditioner; an air supply mechanism, comprising a vaporizer and a buffer tank, wherein the vaporizer is provided with a third heat dissipation pipe, a fourth heat dissipation pipe and a fifth heat dissipation pipe, wherein both ends of the third heat dissipation pipe are respectively connected to the inlet of the LNG storage tank and the buffer tank, both ends of the fourth heat dissipation pipe are respectively connected to the other end of the first heat dissipation pipe and the inlet of the buffer tank, and one end of the fifth heat dissipation pipe is connected to the other end of the heat exchange channel; and, A booster pump, an inlet of which is connected to the cooling housing, and an outlet of which is connected to the other end of the fifth heat dissipation pipe.

2. The gas cylinder temperature increasing and pressurizing and LNG cold energy utilization system according to claim 1 is characterized in that: A heating liquid inlet and a heating liquid outlet communicating with both ends of the heat exchange channel are provided on the side wall of the LNG storage tank.

3. The gas cylinder temperature increasing and pressurizing and LNG cold energy utilization system according to claim 2 is characterized in that: The cooling shell contains a heat exchange medium, and two sides of the cooling shell are respectively provided with a cooling inlet and a cooling outlet. The cooling device also includes a first connecting pipe and a second connecting pipe, one end of the first connecting pipe is connected to the heating liquid outlet, the other end of the first connecting pipe is connected to the cooling inlet, one end of the second connecting pipe is connected to the cooling outlet, and the other end of the second connecting pipe is connected to the inlet of the boosting pump.

4. The gas cylinder temperature increasing and pressurizing and LNG cold energy utilization system according to claim 2 is characterized in that: The vaporizer further includes a third connecting pipe, one end of which is connected to one end of the fifth radiating pipe, and the other end of which is connected to the heating liquid inlet.

5. The gas cylinder temperature increasing and pressurizing and LNG cold energy utilization system according to claim 1 is characterized in that: The cooler also includes a fourth connecting pipe and a fifth connecting pipe, one end of the fourth connecting pipe is connected to the outlet of the LNG storage tank, the other end of the fourth connecting pipe is connected to one end of the first heat dissipation pipe, one end of the fifth connecting pipe is connected to the other end of the first heat dissipation pipe, and the other end of the fifth connecting pipe is connected to one end of the fourth heat dissipation pipe.

6. The gas cylinder temperature increasing and pressurizing and LNG cold energy utilization system according to claim 1 is characterized in that: The vaporizer also includes a sixth connecting pipe and a seventh connecting pipe, one end of the sixth connecting pipe is connected to the outlet of the LNG storage tank, the other end of the sixth connecting pipe is connected to one end of the third heat dissipation pipe, one end of the seventh connecting pipe is connected to the other end of the third heat dissipation pipe, the other end of the seventh connecting pipe is connected to the inlet of the buffer tank, the seventh connecting pipe is provided with a first control valve, and the outlet of the buffer tank is used to connect to the air intake end of the engine.

7. The gas cylinder temperature increasing and pressurizing and LNG cold energy utilization system according to claim 1 is characterized in that: The vaporizer also includes an eighth connecting pipe and a ninth connecting pipe, one end of the eighth connecting pipe is connected to the outlet of the boost pump, the other end of the eighth connecting pipe is connected to one end of the fifth heat dissipation pipe, one end of the ninth connecting pipe is connected to the other end of the fifth heat dissipation pipe, the other end of the ninth connecting pipe is connected to the inlet of the buffer tank, and a second control valve is provided on the ninth connecting pipe.

8. The gas cylinder temperature increasing and pressurizing and LNG cold energy utilization system according to claim 1 is characterized in that: It also includes a heat exchange mechanism, which includes a circulation pump, a plate exchanger, a cold core and a temperature sensor. The inlet of the circulation pump is connected to one end of the second heat dissipation pipe, the outlet of the circulation pump is connected to one end of the plate exchanger, the plate exchanger is connected to the refrigeration air conditioner and is used to provide cold energy for the refrigeration air conditioner, the other end of the plate exchanger is connected to one end of the cold core, the other end of the cold core is connected to the other end of the second heat dissipation pipe, and the temperature sensor is used to detect the temperature of the medium in the heat exchange mechanism.

9. The gas cylinder temperature increasing and pressurizing and LNG cold energy utilization system according to claim 8 is characterized in that: The plate exchanger is also connected to a heating air conditioner and is used to receive heat generated by the heating air conditioner.

10. A control method for a gas cylinder temperature increasing and pressurizing system and a LNG cold energy utilization system as claimed in any one of claims 1 to 9, characterized in that: include: S1. When the pressure in the LNG storage tank is lower than the LNG saturation pressure, the booster pump works to extract the medium in the cold shell into the fifth heat dissipation pipe in the vaporizer. The medium is vaporized in the fifth heat dissipation pipe, absorbs heat, and then flows to the heat exchange channel of the LNG storage tank to exchange heat with the low-temperature LNG in the LNG storage tank, thereby gradually transferring heat to the LNG liquid in the LNG storage tank, thereby heating the LNG liquid and increasing the pressure in the LNG storage tank until the preset LNG saturation pressure is reached, and then the booster pump stops working; S2. When the vehicle is powered on and refrigeration and air conditioning are not needed, the LNG liquid in the LNG storage tank enters the third heat dissipation pipe in the vaporizer, and after being vaporized, enters the buffer tank, and is then discharged from the buffer tank for use by the engine; S3. When the vehicle is powered on and refrigeration and air conditioning is needed, the LNG liquid in the LNG storage tank first enters the first heat dissipation pipe in the refrigeration shell, and exchanges heat with the medium in the refrigeration shell to reduce the temperature of the medium in the refrigeration shell, and then flows to the fourth heat dissipation pipe in the vaporizer for vaporization, and then enters the buffer tank, and then is discharged from the buffer tank for use by the engine; at the same time, the second heat dissipation pipe in the refrigeration device is used to supplement the cooling for the refrigeration and air conditioning.

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