A gas tank pressure management system and method

Abstract

The application relates to a gas tank pressure control system and a control method, which comprises an exhaust control unit and a pressure management unit, and is used for controlling the pressure of multiple gas tanks. The exhaust control unit comprises a Venturi air suction device, the Venturi air suction device has an exhaust passage and an air suction passage, in the multiple gas tanks, one gas tank is connected with the air suction passage through a pipeline, and the remaining gas tanks are connected with the air suction passage and the inlet section of the exhaust passage through pipelines; the pressure management unit is connected with each gas tank through a pipeline, and the pressure management unit comprises a gas catalytic device, the gas evaporated in the gas tank is discharged into the gas catalytic device, the gas catalytic device is filled with a catalyst capable of reacting with the gas, and the gas is liquefied and stored in the gas catalytic device. The application can control the pressure of the gas tank, solves the problems of gas tank pressure overflow due to excessive pressure or gas tank pressure being too low to discharge.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of management and control of gas storage tanks, in particular to a gas storage tank pressure control system and method. BACKGROUND

[0002] LNG (Liquefied Natural Gas) is a clean energy source that has low pollution and low carbon emissions. Its use helps to reduce greenhouse gas emissions and improve environmental quality. With the increasing demand for clean energy worldwide, the LNG industry is rapidly developing, including as a peak shaving gas source for city pipe networks, vehicle fuel, and distributed energy systems.

[0003] In the field of vehicle fuel use, LNG is stored in gas storage tanks. In daily use, the control of gas storage tanks mainly includes exhaust control and pressure management, wherein:

[0004] In terms of exhaust control: existing gas storage tanks generally store high-pressure gas of 700 bar (maximum pressure). The working pressure of the gas outside the gas storage tank is about 260 bar. These gases will be released to the engine for combustion to produce energy. After release, the pressure inside the LNG storage tank decreases. When the gas pressure inside the LNG storage tank decreases to 260 bar or below, due to the high working pressure of the gas outside the gas storage tank, the gas in the gas storage tank cannot be output to the outside of the gas storage tank for use by the engine, resulting in low utilization of the energy of the gas in the LNG storage tank and ineffective use of the storage space of the gas storage tank;

[0005] In terms of pressure management: LNG is stored in double-layer stainless steel storage tanks at a temperature of about -160℃. Due to the large temperature difference between the environment and LNG, heat conduction between the environment and LNG inevitably occurs at any time. Some LNG liquid will evaporate into a gaseous state. In the case of long-term non-operation of the engine, as the amount of LNG evaporated into a gaseous state increases, the pressure inside the LNG storage tank gradually increases. When the pressure exceeds 700 bar, the current LNG storage tank is provided with a safety valve that releases methane to the atmosphere when the pressure inside the tank reaches the set pressure, which can easily pollute the air.

[0006] Therefore, when the gas pressure in the existing LNG storage tank is lower than the working pressure of the gas outside the gas storage tank, the gas storage tank cannot exhaust gas, and this part of gas cannot be utilized. When the pressure is too high, exceeding the upper limit of 700 bar, the existing LNG storage tank either releases the overpressure evaporated natural gas to the atmosphere using a safety valve, or burns it in the engine intake duct, or recovers the overpressure evaporation to the liquid filling station gas tank when filling. SUMMARY

[0007] To this end, the technical problem to be solved by the present application is to overcome the problem of excessively high or low pressure of the gas storage tank in the prior art, and to provide a gas storage tank pressure control system and a control method, which can improve the exhaust efficiency of the gas storage tank and also enable the gas storage tank to exhaust when the pressure is too low, and can control the pressure of the gas storage tank and reduce the pressure in the gas storage tank when the pressure is too high without causing waste.

[0008] To solve the above technical problems, the present application provides a gas storage tank pressure control system, comprising: an exhaust control unit and a pressure management unit for controlling the pressure of a plurality of gas storage tanks, wherein:

[0009] The exhaust control unit comprises a Venturi suction device, the Venturi suction device comprises a Venturi tube, the Venturi tube has an exhaust passage and a suction passage, the exhaust passage comprises an inlet section, a contraction section and an expansion section, the suction passage is in communication with the contraction section through a pipeline, among the plurality of gas storage tanks, one of the gas storage tanks is only in communication with the suction passage through a pipeline, and the remaining gas storage tanks are not only in communication with the suction passage through a pipeline, but also in communication with the inlet section of the exhaust passage through a pipeline;

[0010] The pressure management unit is in communication with each of the gas storage tanks through a pipeline, the pressure management unit comprises a gas catalytic device, the gas evaporated in the gas storage tank is discharged into the gas catalytic device, the gas catalytic device is filled with a catalyst capable of reacting with the gas, and the catalyst reacts with the gas to liquefy the gas and store it in the gas catalytic device.

[0011] In an embodiment of the present application, the number of gas storage tanks is 3-5.

[0012] In an embodiment of the present application, the Venturi suction device further comprises:

[0013] a housing, the Venturi tube is arranged in the housing;

[0014] a first one-way air inlet valve assembly arranged in the housing, the first one-way air inlet valve assembly is in communication with the inlet section of the exhaust passage through a pipeline, and the first one-way air inlet valve assembly controls the gas to enter only from the inlet section;

[0015] a second one-way air inlet valve assembly arranged in the housing, the second one-way air inlet valve assembly is in communication with the inlet section of the suction passage through a pipeline, and the second one-way air inlet valve assembly controls the gas to enter only from the suction passage.

[0016] In an embodiment of the present application, the first one-way air inlet valve assembly and the second one-way air inlet valve assembly each comprise:

[0017] a valve plug and an elastic member, the elastic member elastically supporting the valve plug to block the gas inlet;

[0018] when gas flows from the valve plug to the elastic member, the gas pushes the valve plug to compress the elastic member, the valve plug separates from the gas inlet, the gas inlet opens, and the gas passes through;

[0019] when gas flows from the elastic member to the valve plug, the gas pushes the valve plug to block the gas inlet.

[0020] In one embodiment of the present application, a switch check cut-off valve is arranged on the pipeline between the gas tank and the Venturi suction device.

[0021] In one embodiment of the present application, the exhaust control unit further comprises an accumulator, the accumulator is in communication with the expansion section of the exhaust passage through a pipeline, the gas in the gas tank is discharged into the accumulator, and a pressure sensor is arranged on the accumulator.

[0022] In one embodiment of the present application, the gas tank stores liquefied natural gas or hydrogen.

[0023] In one embodiment of the present application, the pressure management unit comprises a gas inlet pipe connecting the gas tank and the gas catalytic device, the gas inlet pipe extends into the interior of the gas tank, and the gas inlet pipe is arranged at the highest point of the gas phase space in the interior of the gas tank.

[0024] In one embodiment of the present application, a switch control valve is further arranged on the communication pipeline between the gas tank and the gas catalytic device.

[0025] In one embodiment of the present application, the switch control valve is a pressure control valve and can be automatically started according to the gas pressure in the gas tank.

[0026] In one embodiment of the present application, the gas catalytic device has a vent.

[0027] In one embodiment of the present application, a liquid level detection sensor is arranged in the gas catalytic device.

[0028] In one embodiment of the present application, a water cooling system is arranged in the gas catalytic device, and the temperature of the gas catalytic device is controlled through the water cooling system.

[0029] In one embodiment of the present application, the application is applied in the field of automobile gas supply, and the cooling liquid of the automobile engine can be introduced into the water cooling system.

[0030] To solve the above technical problems, the application further provides a gas tank pressure control method, which is implemented by using the above gas tank pressure control system and comprises the following steps:

[0031] When the gas tank is in normal use:

[0032] S101, determine the number of gas tanks, open the first gas tank, make the gas in the first gas tank enter from the air suction channel of the Venturi tube, discharge the gas in the first gas tank into the pressure accumulator, stop the gas discharge process when the gas pressure in the first gas tank is equal to the gas pressure in the pressure accumulator, and a certain amount of residual gas remains in the first gas tank;

[0033] S102, open the second gas tank, make the gas in the second gas tank enter from the gas discharge channel of the Venturi tube, discharge the gas in the second gas tank into the pressure accumulator, when the gas in the second gas tank passes through the contraction section of the Venturi tube, the flow rate increases and the pressure decreases, at this time, the residual gas in the first gas tank is adsorbed and discharged from the air suction channel of the Venturi tube into the pressure accumulator;

[0034] S103, refer to step S102, open the subsequent gas tank in turn, make the gas in the subsequent gas tank enter from the gas discharge channel of the Venturi tube, and make the residual gas in the previous gas tank enter from the air suction channel of the Venturi tube, so that the gas in the two gas tanks is discharged into the pressure accumulator together;

[0035] When the gas tank is not in use:

[0036] S201, the pressure in the gas tank continuously increases, when a pressure difference is formed between the gas tank and the gas catalytic device, and when the pressure difference reaches a threshold control pressure, the gas catalytic device is controlled to be in communication with the gas tank, the gas in the gas tank is guided into the gas catalytic device, and the pressure balance between the gas tank and the gas catalytic device is achieved;

[0037] S202, after the pressure balance, the gas catalytic device is controlled to be not in communication with the gas tank, the gas is liquefied in the gas catalytic device, the pressure is reduced, and the pressure difference between the gas tank and the gas catalytic device is formed again;

[0038] S203, the gas catalytic device is controlled to be in communication with the gas tank again, the gas in the gas tank is guided into the gas catalytic device, the pressure balance between the gas tank and the gas catalytic device is achieved, and the above step S202 is repeated until the pressure difference between the gas tank and the gas catalytic device is lower than the threshold control pressure.

[0039] The above technical scheme of the application has the following advantages compared with the prior art:

[0040] The gas tank pressure control system and control method can control the pressure of the gas tank:

[0041] Firstly, the gas tank pressure control system of the present application utilizes the Venturi tube's air suction characteristics to realize the gas tank exhaust control. The gas tank is connected with the exhaust channel and the air suction channel of the Venturi tube. The gas in the previous gas tank is exhausted through the Venturi tube. When the gas pressure in the gas tank is equal to or lower than the use pressure, a certain amount of gas remains in the gas tank. At this time, the gas in the next gas tank is introduced into the exhaust channel of the Venturi tube. When the gas in the next gas tank passes through the contraction section of the Venturi tube, the flow rate of the gas increases and the pressure decreases. At this time, the residual gas in the previous gas tank is sucked and exhausted from the air suction channel of the Venturi tube, achieving the secondary exhaust effect. At this time, even if the gas pressure in the previous gas tank is lower than the use pressure, the gas can still be exhausted. Therefore, the gas can be exhausted when the pressure of the gas tank is low, and the utilization rate of the gas energy in the gas tank can be improved, and the storage space of the gas tank can be effectively utilized.

[0042] Secondly, the gas catalytic device can chemically react with the gas in the gas tank. When the gas pressure in the gas tank is too high, the gas is controlled to be discharged into the gas catalytic device, and is liquefied and recovered in the gas catalytic device. On the premise of not causing waste, the pressure in the gas tank can be reduced, and the gas can be prevented from being discharged into the air to avoid air pollution. BRIEF DESCRIPTION OF DRAWINGS

[0043] In order to make the content of the present application more easily understood, the present application will be further described in detail below according to the specific embodiments of the present application and in conjunction with the drawings, in which:

[0044] Figure 1 is a structural schematic diagram of the gas tank pressure control system of the present application;

[0045] Figure 2 is a structural schematic diagram of the pressure management unit in the gas tank pressure control system of the present application;

[0046] Figure 3 is a structural schematic diagram of the Venturi air suction device of the present application;

[0047] Figure 4 is a step flow chart of the exhaust control of the gas tank pressure control method of the present application;

[0048] Figure 5 is a step flow chart of the pressure management of the gas tank pressure control method of the present application.

[0049] The description reference signs are as follows: 1, gas storage tank; 2, exhaust control unit; 21, Venturi suction device; 211, Venturi tube; 212, shell; 213, first one-way air inlet valve assembly; 214, second one-way air inlet valve assembly; 22, on-off check valve; 3, pressure management unit; 31, gas catalytic device; 32, air inlet pipe; 33, on-off control valve. DETAILED DESCRIPTION

[0050] The present application will be further described below in conjunction with the drawings and specific examples, so that those skilled in the art can better understand the present application and implement it, but the examples are not limiting the present application. EMBODIMENT

[0051] REFERENCE Figure 1 As shown in the drawings, the present application discloses a gas storage tank pressure control system for realizing the control of the gas pressure in multiple gas storage tanks 1, comprising: an exhaust control unit 2 and a pressure management unit 3, wherein: the exhaust control unit 2 can discharge gas from the gas storage tank 1 when the gas pressure in the gas storage tank 1 is insufficient, which can improve the utilization rate of the gas energy in the gas storage tank 1 and effectively utilize the storage space of the gas storage tank 1, and the pressure management unit 3 can liquefy and recover the gas when the gas pressure in the gas storage tank 1 is too high, thereby avoiding gas overflow and causing waste and pollution.

[0052] The exhaust control unit 2 comprises a Venturi suction device 21, the Venturi suction device 21 comprises a Venturi tube 211, the Venturi tube 211 has an exhaust passage and a suction passage, the exhaust passage comprises: an inlet section, a contraction section and an expansion section, the suction passage is communicated with the contraction section through a pipeline, among the multiple gas storage tanks 1, one of the gas storage tanks 1 is only communicated with the suction passage through a pipeline, and the remaining gas storage tanks 1 are not only communicated with the suction passage through a pipeline, but also communicated with the inlet section of the exhaust passage through a pipeline;

[0053] In the embodiment, the Venturi tube 211 is used to realize the exhaust control of the gas tank 1. The gas tank 1 is communicated with the exhaust passage and the suction passage of the Venturi tube 211. The gas in the previous gas tank 1 is exhausted through the Venturi tube 211. When the pressure of the gas in the gas tank 1 is equal to or lower than the use pressure, a certain amount of gas remains in the gas tank 1. At this time, the gas in the next gas tank 1 is exhausted through the exhaust passage of the Venturi tube 211. When the gas in the next gas tank 1 passes through the contraction section of the Venturi tube 211, the flow rate of the gas increases and the pressure of the gas decreases. At this time, the remaining gas in the previous gas tank 1 is exhausted from the suction passage of the Venturi tube 211, so that the secondary exhaust is realized. At this time, even if the pressure of the gas in the previous gas tank 1 is lower than the use pressure, the gas can be exhausted. Therefore, the gas can be exhausted when the pressure of the gas in the gas tank 1 is low. The utilization rate of the gas energy in the gas tank 1 is improved, and the storage space of the gas tank 1 is effectively utilized.

[0054] Referring to Figure 1 In the embodiment, the exhaust control unit 2 of the gas tank with three gas tanks 1 is taken as an example to further illustrate the exhaust control unit 2 of the gas tank.

[0055] As shown in the figure, in the embodiment, three gas tanks 1 are provided, which are a first gas tank, a second gas tank and a third gas tank. In the embodiment, the three gas tanks 1 are provided.

[0056] The first gas tank is communicated with the suction passage of the Venturi tube 211 in the Venturi suction device 21 through a pipeline;

[0057] The second gas tank is communicated with the suction passage and the exhaust passage of the Venturi tube 211 in the Venturi suction device 21 through a pipeline;

[0058] The third gas tank is communicated with the exhaust passage of the Venturi tube 211 in the Venturi suction device 21 through a pipeline.

[0059] The above-mentioned exhaust control system of the gas tank 1 is used to exhaust the gas in the first gas tank, the second gas tank and the third gas tank into the pressure accumulator for use of the engine. Therefore, the pressure accumulator is communicated with the expansion section of the exhaust passage through a pipeline, so that the gas in the gas tank 1 is exhausted into the pressure accumulator. The specific exhaust process is as follows:

[0060] Firstly, the first gas tank is opened, the gas in the first gas tank is exhausted from the suction passage of the Venturi tube 211, and the gas in the first gas tank is exhausted into the pressure accumulator. When the pressure of the gas in the first gas tank is equal to the pressure of the gas in the pressure accumulator, the exhaust process is stopped, and a certain amount of gas remains in the first gas tank 1;

[0061] The gas in the No. 2 gas tank is allowed to enter the exhaust passage of the Venturi tube 211, and the gas in the No. 2 gas tank is discharged into the pressure accumulator. When the gas in the No. 2 gas tank passes through the converging section of the Venturi tube 211, the flow rate of the gas increases, and the pressure of the gas decreases. At this time, the Venturi effect is generated, and the residual gas in the No. 1 gas tank is sucked again from the suction passage of the Venturi tube 211 and discharged into the pressure accumulator. As a result, the residual gas in the No. 1 gas tank is further reduced.

[0062] When the pressure of the gas in the No. 2 gas tank is equal to the pressure of the gas in the pressure accumulator, the exhaust process is stopped. The No. 3 gas tank is opened again, and the gas in the No. 3 gas tank is allowed to enter the exhaust passage of the Venturi tube 211. The gas in the No. 3 gas tank is discharged into the pressure accumulator. When the gas in the No. 3 gas tank 3 passes through the converging section of the Venturi tube 211, the flow rate of the gas increases, and the pressure of the gas decreases. At this time, the Venturi effect is generated, and the residual gas in the No. 1 gas tank and the residual gas in the No. 2 gas tank are collectively sucked again from the suction passage of the Venturi tube 211 and discharged into the pressure accumulator. As a result, the residual gas in the No. 1 gas tank and the No. 2 gas tank is further reduced.

[0063] As can be seen, at this time, only the gas in the No. 3 gas tank has the same pressure as the gas in the pressure accumulator, and the pressures of the gases in the No. 1 gas tank and the No. 2 gas tank are all less than the pressure of the gas in the pressure accumulator. The problem that the gas in the No. 1 gas tank cannot be discharged when the pressure of the gas in the No. 1 gas tank is equal to the use working pressure in the prior art is solved. In comparison, in the present application, the gas in the No. 1 gas tank and the No. 2 gas tank can be partially discharged when the pressure of the gas is less than the use working pressure. Therefore, the utilization rate of the gas energy in the No. 1 gas tank can be improved, and the storage space of the No. 1 gas tank can be effectively utilized.

[0064] Specifically, according to actual experimental verification, when three No. 1 gas tanks are provided, the gas in the No. 3 gas tank is allowed to enter the pressure accumulator through the exhaust passage of the Venturi tube 211. When the pressure of the gas in the No. 3 gas tank is equal to the pressure of the gas in the pressure accumulator, the gas in the No. 1 gas tank is substantially completely passively discharged through two times of the Venturi effect. Therefore, when the gas discharge control system of the No. 1 gas tank is used, the efficiency of the gas discharge is maximized when three or more than three No. 1 gas tanks are provided. In theory, the more the No. 1 gas tanks are provided, the higher the efficiency is. However, according to actual use requirements, the application scene and the land distribution should also be considered. In general, three to five No. 1 gas tanks are provided in the vehicle-mounted engine, which is the best configuration. The efficiency is maximized, and the actual setting condition is met.

[0065] In the embodiment, three gas storage tanks 1 are arranged to form a gas storage tank 1 exhaust control system. In order to facilitate subsequent expansion, the third gas storage tank is also connected to the gas inlet channel of the Venturi tube 211 in the Venturi suction device 21 through a pipeline, so as to facilitate subsequent increase in the number of gas storage tanks 1.

[0066] Specifically, in order to realize the communication control of different gas storage tanks 1 and the Venturi tube 211, a switch check valve 22 is arranged on the pipeline between the gas storage tank 1 and the Venturi suction device 21.

[0067] Specifically, according to actual use requirements, the gas storage tank 1 stores liquefied natural gas, hydrogen or other flammable gas.

[0068] Specifically, when the Venturi tube 211 is used, the one-way flow of the gas flow needs to be ensured, that is, when the gas flow enters from the gas outlet channel of the Venturi tube 211, the gas flow can only flow in the direction from the inlet section, the contraction section to the expansion section, and when the gas flow enters from the gas inlet channel of the Venturi tube 211, the gas flow can only be discharged from the expansion section.

[0069] In order to realize the one-way flow described above, referring to Figure 3 The Venturi suction device 21 of the present application further comprises a housing 212, a first one-way gas inlet valve assembly 213 and a second one-way gas inlet valve assembly 214, wherein the Venturi tube 211, the first one-way gas inlet valve assembly 213 and the second one-way gas inlet valve assembly 214 are all arranged in the housing 212, the first one-way gas inlet valve assembly 213 is connected to the inlet section of the gas outlet channel through a pipeline, the first one-way gas inlet valve assembly 213 controls the gas to enter only from the inlet section, the second one-way gas inlet valve assembly 214 is connected to the inlet section of the gas inlet channel through a pipeline, and the second one-way gas inlet valve assembly controls the gas to enter only from the gas inlet channel.

[0070] In the embodiment, the first one-way gas inlet valve assembly 213 and the second one-way gas inlet valve assembly 214 are similar in structure, and both comprise a valve plug and an elastic member, the elastic member elastically supports the valve plug to block the gas inlet.

[0071] When the gas flows from the valve plug to the elastic member, the gas pushes the valve plug to compress the elastic member, the valve plug is separated from the gas inlet, the gas inlet is opened, and the gas passes through.

[0072] When the gas flows from the elastic member to the valve plug, the gas pushes the valve plug to block the gas inlet.

[0073] Referring to Figure 1 andFigure 2 As shown, the pressure management unit 3 is in communication with each of the gas tanks 1 through a pipeline, the pressure management unit 3 includes a gas catalytic device 31, the gas evaporated in the gas tank 1 is discharged into the gas catalytic device 31, the gas catalytic device 31 is filled with a catalyst capable of reacting with the gas, the catalyst reacts with the gas to liquefy the gas and store it in the gas catalytic device 31, when the gas pressure in the gas tank 1 is too high, the gas is controlled to be discharged into the gas catalytic device 31, and is liquefied and recovered in the gas catalytic device 31, which can reduce the pressure in the gas tank 1 without causing waste, and can also prevent the gas from being discharged into the air to avoid air pollution.

[0074] Specifically, in the gas tank 1, gas evaporation will exist at the top of the gas tank 1, therefore, in the present embodiment, the pressure management unit 3 includes a gas inlet pipe 32 connecting the gas tank 1 and the gas catalytic device 31, the gas inlet pipe 32 extends into the interior of the gas tank 1, and the gas inlet pipe 32 is arranged at the highest point of the gas phase space in the interior of the gas tank 1.

[0075] Specifically, the gas inlet pipe 32 is also provided with an on-off control valve 33, and there are two control modes for setting the on-off control valve 33 during actual use:

[0076] First, the on-off control valve 33 can be set as a solenoid valve, a pressure sensor is arranged in each of the gas tanks 1, the pressure in the gas tank 1 is detected in real time by the pressure sensor, a detection threshold value of the pressure sensor is set, when the pressure reaches the threshold value, an electric signal is transmitted from the pressure sensor to the on-off control valve 33, so as to control the opening and closing of the solenoid valve.

[0077] Second, the on-off control valve 33 can be set as a pressure control valve, which can be automatically started according to the gas pressure in the gas tank 1, that is, when the gas tank 1 and the gas catalytic device 31 are connected, the opening and closing are realized through the pressure difference between them, specifically, the pressure control valve includes:

[0078] A mechanical pressure control valve, by setting a spring opening pressure, the pressure in the gas tank 1 can be controlled at a constant value, when the evaporation pressure in the gas tank 1 is higher than the set value, the control valve spring is opened, the gas in the tank flows to the gas catalytic device 31 through the pressure control valve and is liquefied in the gas catalytic device 31, as more and more gas is liquefied, the gas evaporation pressure in the gas tank 1 gradually decreases, when it is lower than the set value of the pressure control valve spring, the pressure control valve is automatically closed, so as to always control the gas pressure in the gas tank 1 at the set value.

[0079] The electrically controlled pressure control valve can directly set the pressure setting value of the pressure valve, thereby flexibly adjusting the pressure in the gas storage tank 1, and the pressure adjustment principle is basically the same as that of the mechanical pressure control valve.

[0080] Specifically, in the present embodiment, the gas catalytic device 31 further has a discharge port, a discharge valve is further arranged on the discharge port, and a discharge pipeline is connected to the recovery tank at the discharge port. The discharge valve controls the opening and closing of the discharge port, and the liquefied liquid in the gas catalytic device 31 can be recovered.

[0081] Specifically, a liquid level detection sensor is arranged in the gas catalytic device 31. When the liquid level detection sensor detects that the liquid in the gas catalytic device 31 reaches a storage threshold, the liquid level detection sensor generates an electrical signal to control the discharge valve to open, so as to realize the discharge of the liquid, so as to prevent the gas catalytic device 31 from being full and unable to realize the liquefaction of the gas.

[0082] Specifically, a water cooling system is arranged in the gas catalytic device 31. The water cooling system controls the temperature of the gas catalytic device 31, which can improve the liquefaction speed of the gas and optimize the reaction efficiency of the catalyst. When the gas storage tank 1 of the present application is applied in the field of automobile gas supply, the cooling liquid of the automobile engine can be introduced into the water cooling system during actual arrangement. The engine cooling liquid can provide a temperature of 80-90 degrees Celsius for the gas catalytic device 31 during engine operation, effectively improving the activity of the catalyst.

[0083] Specifically, taking the storage of natural gas in the gas storage tank 1 as an example: the main component of natural gas is methane. In the prior art: graphene limited single iron center, ZSM-5 channel lattice limited coordination unsaturated single center iron and double center iron site can all activate hydrogen peroxide to produce active Fe-O species. This species can effectively activate methane and dissociate carbon-hydrogen bonds, so that methane (the main component of natural gas, molecular formula CH4) is oxidized to formic acid (HCOOH) with high selectivity through a free radical mechanism via methanol (CH3OH) and formaldehyde (HCHO), and the generation of carbon dioxide is effectively inhibited. By changing the silicon-aluminum ratio of the ZSM-5 molecular sieve and the Fe loading of the catalyst, the conversion efficiency is highest at 80°C. Therefore, the engine cooling liquid can provide a better conversion environment during engine operation. After the natural gas is catalytically reacted to formic acid, the pressure in the gas catalytic device 31 is greatly reduced, thereby providing the necessary space to transfer more natural gas with a pressure higher than that in the gas catalytic device 31 from the gas storage tank 1 to the gas catalytic device 31 for further chemical reaction. Embodiment

[0084] The gas storage tank pressure control system of the above embodiment 1 is applied, and the pressure control valve is controlled by the pressure control system. Figures 4-5As shown, the application also discloses a management control method, comprising the following steps:

[0085] When the gas tank is in normal use:

[0086] S101, determine the number of gas tanks, open the first gas tank, make the gas in the first gas tank enter from the air suction channel of the venturi tube, discharge the gas in the first gas tank into the pressure accumulator, stop the gas discharge process when the gas pressure in the first gas tank is equal to the gas pressure in the pressure accumulator, and a certain amount of gas remains in the first gas tank;

[0087] S102, open the second gas tank, make the gas in the second gas tank enter from the gas discharge channel of the venturi tube, discharge the gas in the second gas tank into the pressure accumulator, when the gas in the second gas tank passes through the contraction section of the venturi tube, the flow rate increases and the pressure decreases, at this time, the residual gas in the first gas tank is adsorbed and discharged from the air suction channel of the venturi tube into the pressure accumulator;

[0088] S103, refer to step S102, open the subsequent gas tank in turn, make the gas in the subsequent gas tank enter from the gas discharge channel of the venturi tube, make the residual gas in the previous gas tank enter from the air suction channel of the venturi tube, and discharge the gas in the two gas tanks into the pressure accumulator together;

[0089] When the gas tank is not in use:

[0090] S201, the pressure in the gas tank is continuously increased, when the pressure difference between the gas tank and the gas catalytic device reaches the threshold control pressure, the gas catalytic device is controlled to be communicated with the gas tank, the gas in the gas tank is introduced into the gas catalytic device, and the pressure balance between the gas tank and the gas catalytic device is achieved;

[0091] S202, after the pressure balance, the gas catalytic device is controlled to be not communicated with the gas tank, the gas is liquefied in the gas catalytic device, the pressure is reduced, and the pressure difference between the gas tank and the gas catalytic device is formed again;

[0092] S203, the gas catalytic device is controlled to be communicated with the gas tank again, the gas in the gas tank is introduced into the gas catalytic device, the pressure balance between the gas tank and the gas catalytic device is achieved, and the above step S202 is repeated until the pressure difference between the gas tank and the gas catalytic device is lower than the threshold control pressure.

[0093] The specific implementation steps of the gas tank pressure control method of the application have been illustrated in embodiment 1, and will not be repeated here. Through the gas tank pressure control system of the application, the pressure of the gas tank can be controlled:

[0094] When the pressure in the single gas tank is insufficient, the gas with a pressure lower than the working pressure can be discharged from the gas tank by the exhaust control unit, the utilization rate of the gas energy in the gas tank can be improved, and the storage space of the gas tank can be effectively utilized;

[0095] When the pressure in the single gas tank is too large, the evaporated gas is reacted with the catalyst to generate liquid by the pressure management unit, the pressure in the gas tank can be reduced without waste, the gas can be prevented from being discharged into the air, and air pollution can be avoided.

[0096] Obviously, the above embodiments are only examples for clearly illustrating the present application, and are not intended to limit the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, all the embodiments cannot be exhausted, and the obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A gas tank pressure management system, characterized by, The application relates to a gas storage device. The gas storage device comprises an exhaust control unit and a pressure management unit, which are used for controlling the pressure of a plurality of gas storage tanks. The exhaust control unit comprises a Venturi suction device, which comprises a Venturi tube having an exhaust passage and a suction passage. The exhaust passage comprises an inlet section, a contraction section and an expansion section.

2. The gas holder pressure management system of claim 1, wherein: The suction passage is communicated with the contraction section through a pipeline.

3. The gas holder pressure management system of claim 1, wherein: One of the gas storage tanks is communicated with the suction passage through a pipeline. The remaining gas storage tanks are communicated with the suction passage and the inlet section of the exhaust passage through pipelines. The pressure management unit is communicated with each of the gas storage tanks through a pipeline. The pressure management unit comprises a gas catalytic device.

4. The gas holder pressure management system of claim 3, wherein: The gas evaporated in the gas storage tank is discharged into the gas catalytic device. The gas catalytic device is filled with a catalyst capable of reacting with the gas. The catalyst reacts with the gas to liquefy the gas and store the liquefied gas in the gas catalytic device. The number of the gas storage tanks is 3-5.

5. The gas holder pressure management system of claim 1, wherein: The Venturi suction device further comprises:

6. The gas holder pressure management system of claim 1, wherein: A housing, wherein the Venturi tube is arranged in the housing.

7. The gas holder pressure management system of claim 1, wherein: A first one-way air inlet valve assembly arranged in the housing.

8. The gas holder pressure management system of claim 1, wherein: The first one-way air inlet valve assembly is communicated with the inlet section of the exhaust passage through a pipeline.

9. The gas holder pressure management system of claim 1, wherein: The first one-way air inlet valve assembly controls the gas to enter only from the inlet section.

10. The gas holder pressure management system according to claim 9, wherein: A second one-way air inlet valve assembly arranged in the housing.

11. The gas holder pressure management system of claim 1, wherein: The second one-way air inlet valve assembly is communicated with the inlet section of the suction passage through a pipeline.

12. The gas holder pressure management system of claim 1, wherein: The second one-way air inlet valve assembly controls the gas to enter only from the suction passage.

13. The gas holder pressure management system of claim 1, wherein: The first one-way air inlet valve assembly and the second one-way air inlet valve assembly each comprise: A valve plug and an elastic member. When the gas flows from the valve plug to the elastic member, the gas pushes the valve plug to compress the elastic member. The valve plug is separated from the air inlet, the air inlet is opened, and the gas passes through. When the gas flows from the elastic member to the valve plug, the gas pushes the valve plug to block the air inlet. A switch check cut-off valve is arranged on the pipeline between the gas storage tank and the Venturi suction device. The exhaust control unit further comprises an accumulator communicated with the expansion section of the exhaust passage through a pipeline. The gas in the gas storage tank is discharged into the accumulator. A pressure sensor is arranged on the accumulator. The gas storage tank stores liquefied natural gas or hydrogen. The pressure management unit comprises an air inlet pipe communicated with the gas storage tank and the gas catalytic device. The air inlet pipe extends into the interior of the gas storage tank. The air inlet pipe is arranged at the highest point of the gas phase space in the gas storage tank. A switch control valve is arranged on the communication pipeline between the gas storage tank and the gas catalytic device. The switch control valve is a pressure control valve and can be automatically started according to the gas pressure in the gas storage tank. The gas catalytic device has a discharge port. A liquid level detection sensor is arranged in the gas catalytic device. A water cooling system is arranged in the gas catalytic device to control the temperature of the gas catalytic device.

14. The gas holder pressure management system of claim 13, wherein: The application is applied in the field of automobile gas supply, and the cooling liquid of the automobile engine can be introduced into the water cooling system.

15. A method for controlling pressure of a gas storage tank, implemented by using the gas storage tank pressure control system according to any one of claims 1-14, characterized in that: The method comprises the following steps: When the gas tank is in normal use: S101, determine the number of gas tanks, open the first gas tank, make the gas in the first gas tank enter from the air suction channel of the Venturi tube, discharge the gas in the first gas tank into the pressure accumulator, stop the gas discharge process when the gas pressure in the first gas tank is equal to the gas pressure in the pressure accumulator, and a certain amount of gas remains in the first gas tank; S102, open the second gas tank, make the gas in the second gas tank enter from the gas discharge channel of the Venturi tube, discharge the gas in the second gas tank into the pressure accumulator, when the gas in the second gas tank passes through the contraction section of the Venturi tube, the flow rate increases and the pressure decreases, at this time, the residual gas in the first gas tank is adsorbed and discharged from the air suction channel of the Venturi tube into the pressure accumulator; S103, refer to step S102, open the subsequent gas tank in turn, make the gas in the subsequent gas tank enter from the gas discharge channel of the Venturi tube, make the residual gas in the previous gas tank enter from the air suction channel of the Venturi tube, and discharge the gas in the two gas tanks into the pressure accumulator together; When the gas tank is not in use: S201, the pressure in the gas tank continuously increases, when a pressure difference is formed between the gas tank and the gas catalytic device, when the pressure difference reaches a threshold control pressure, control the gas catalytic device to communicate with the gas tank, guide the gas in the gas tank into the gas catalytic device, and balance the pressure between the gas tank and the gas catalytic device; S202, after pressure balance, control the gas catalytic device to not communicate with the gas tank, liquefy the gas in the gas catalytic device, reduce the pressure, and form a pressure difference between the gas tank and the gas catalytic device again; S203, control the gas catalytic device to communicate with the gas tank again, guide the gas in the gas tank into the gas catalytic device, balance the pressure between the gas tank and the gas catalytic device, repeat step S202 until the pressure difference between the gas tank and the gas catalytic device is lower than the threshold control pressure.

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