A catalytic inerting system and method with controllable fuel vapor concentration

Abstract

The application discloses a catalytic inerting system and method with controllable fuel vapor concentration. The outlet of a fuel tank is connected with the inlet of an air extractor, the outlet of the air extractor is connected with the inlet of a flow regulating valve and the inlet of a vapor oil tank, the outlet of the flow regulating valve and the outlet of the vapor oil tank are connected with the inlet of a catalytic reactor, the inlet of the vapor oil tank is provided with a fuel vapor generating device, the fuel vapor generating device is arranged below the liquid level of the vapor oil tank, the outlet of the catalytic reactor is connected with the hot side inlet of a heat exchanger, the hot side outlet of the heat exchanger is connected with the inlet of a water separator, and the outlet of the water separator is connected with the inlet of the fuel tank. The application improves the adjusting capacity of the system and effectively improves the inerting performance of the catalytic inerting system.

Description

Technical Field

[0001] This invention belongs to the field of aircraft fuel tank fire prevention and explosion suppression technology, and relates to a catalytic inerting system and method with controllable fuel vapor concentration. Background Technology

[0002] Fires and explosions in aircraft fuel systems are one of the main causes of various aircraft accidents. Currently, both military and civilian aircraft must take effective measures to prevent fuel tank combustion and explosion. Since the late 1970s, hollow fiber membrane airborne nitrogen inerting systems have been widely used, but they still have many problems in use, such as the need to bleed air from the engine or the membrane fibers being prone to clogging.

[0003] In recent years, some researchers have proposed a method based on catalytic oxidation to consume oxygen in the upper gas phase space of the fuel tank, thereby reducing the fuel tank's combustibility. This novel oxygen-consuming catalytic inerting system has rapidly gained widespread attention due to its advantages such as not requiring bleed air from the engine, light weight, and no pollution. However, for existing oxygen-consuming catalytic inerting system architectures, such as "A Catalytic Inerting System and Control Method with Bypass Branch Control" (CN 114313279 B) which improves system operational safety, and "A Flow-Shifting Oxygen-Consuming Inerting System" (CN 110053780 B) which improves reaction uniformity based on flow direction change, researchers have found in experimental tests that the operating state of this system architecture is greatly affected by the fuel vapor concentration of the drawn-in gas, and varies with changes in fuel tank level, ambient temperature, etc. When the fuel tank load is low, or the ambient temperature is low, the fuel vapor concentration of the drawn-in gas is much lower than the saturated fuel vapor concentration, resulting in very low catalytic efficiency and poor inerting performance. As the reduction in fuel load and ambient temperature are inevitable throughout the flight envelope, the catalytic inerting system will operate under extremely poor conditions for a long time, and may even shut down and lose its inerting ability. Summary of the Invention

[0004] The purpose of this invention is to provide a catalytic inerting system and method with controllable fuel vapor concentration. This invention improves the system's adjustability and can effectively enhance the inerting performance of the catalytic inerting system.

[0005] The technical solution of the present invention is as follows: a catalytic inerting system with controllable fuel vapor concentration, comprising a fuel tank, the fuel tank outlet being connected to the inlet of an exhaust fan, the exhaust fan outlet being connected to the inlet of a flow regulating valve and the inlet of a vapor tank, the flow regulating valve and the vapor tank outlet being connected to the inlet of the catalytic reactor reaction gas; a fuel vapor generator is provided at the vapor tank inlet, the fuel vapor generator being built below the liquid level of the vapor tank; the catalytic reactor reaction gas outlet is connected to the hot edge inlet of a heat exchanger, the hot edge outlet of the heat exchanger is connected to the inlet of a water separator, and the water separator outlet is connected to the fuel tank inlet.

[0006] In the aforementioned catalytic inerting system with controllable fuel vapor concentration, a heating channel is provided on the vapor tank. The inlet of the heating channel is connected to the cold side outlet of the heat exchanger, and the cold side inlet of the heat exchanger is connected to the outlet of the second heat exchange fan.

[0007] In the aforementioned catalytic inerting system with controllable fuel vapor concentration, a second electric heater is installed on the vapor tank.

[0008] In the aforementioned catalytic inerting system with controllable fuel vapor concentration, the fuel tank outlet and inlet are equipped with a first flame suppressor and a second flame suppressor, respectively.

[0009] In the aforementioned catalytic inerting system with controllable fuel vapor concentration, the catalytic reactor is connected to a first electric heater located at the inlet of the catalytic reactor via an electric heating connection port.

[0010] In the aforementioned catalytic inerting system with controllable fuel vapor concentration, the catalytic reactor is equipped with a cooling channel, and the cold side inlet of the cooling channel is connected to the first heat exchange fan.

[0011] A method for operating a catalytic inerting system with controllable fuel vapor concentration, as described above, involves a fuel tank outlet mixture containing fuel vapor being pressurized by an exhaust fan and then entering a flow regulating valve and a vapor tank. The mixture entering the vapor tank is then passed through a fuel vapor generator to increase the fuel vapor concentration. The mixture with increased fuel vapor concentration is then further mixed with the mixture at the outlet of the flow regulating valve and enters a catalytic reactor. After treatment in the catalytic reactor, a mixed inert gas is generated. The mixed inert gas is then cooled in a heat exchanger and dehydrated by a water separator before returning to the fuel tank.

[0012] In the aforementioned working method of the catalytic inerting system with controllable fuel vapor concentration, after heat exchange in the heat exchanger, the gas at 50-80°C at the cold side outlet enters the heating channel of the vapor tank to heat the vapor tank, further increasing the fuel vapor concentration of the mixture at the outlet of the vapor tank.

[0013] In the aforementioned working method of the catalytic inerting system with controllable fuel vapor concentration, the vapor tank is directly heated by a second electric heater.

[0014] Compared with the prior art, the present invention has the following advantages:

[0015] To address the problems of uncontrollable and limited adjustment capabilities of fuel vapor concentration in existing catalytic inerting systems, this invention proposes a catalytic inerting system with controllable fuel vapor concentration. By incorporating a bypass branch at the exhaust fan outlet, the gas in the bypass branch, after passing through a fuel vapor generator, carries abundant fuel vapor and mixes with the main gas, which has a lower fuel vapor concentration. By adjusting the gas flow ratio between the main and bypass branches, the fuel vapor concentration of the reactant gas entering the catalytic reactor can be controlled. This allows the entire system to operate stably under optimal conditions below the flight envelope, significantly improving the system's adjustability and effectively enhancing the inerting performance of the catalytic inerting system. Specifically, the advantages of this invention compared to existing technologies are:

[0016] 1) The present invention provides a catalytic inerting system with controllable fuel vapor concentration. By setting a bypass branch at the outlet of the exhaust fan, the gas in the bypass branch can carry sufficient fuel vapor after passing through the fuel vapor generator, thereby increasing the fuel vapor concentration of the reaction gas entering the catalytic reactor and greatly improving the inerting performance of the system. Under the same working conditions, the initial ground inerting time can be reduced by more than 20%.

[0017] 2) The catalytic inerting system with controllable fuel vapor concentration of the present invention can dynamically adjust the fuel vapor concentration of the reaction gas entering the catalytic reactor from hundreds of ppm to thousands of ppm by adjusting the gas volume ratio of the main road and the bypass branch, so that the system can operate stably under the entire flight envelope, greatly improving the system's adjustment capability and safety.

[0018] 3) The catalytic inerting system with controllable fuel vapor concentration of the present invention increases the fuel temperature in the vapor tank by setting an electric heater or using the waste heat of the gas exchanger, thereby further increasing the controllable range of fuel vapor concentration in the inlet gas of the catalytic reactor. This allows the system to maintain fuel vapor concentration even in low-temperature environments, effectively expanding the operating condition boundaries of the catalytic inerting system. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a catalytic inerting system with controllable fuel vapor concentration according to the present invention;

[0020] Figure 2 This is a schematic diagram of the catalytic inerting system for heating a steam oil tank using waste heat from a heat exchanger, as described in this invention.

[0021] Figure 3 This is a schematic diagram of the catalytic inerting system with electric heating capability in the steam tank of the present invention.

[0022] Among them, 1-fuel tank, 2-first check valve, 3-first flame suppressor, 4-first shut-off valve, 5-exhaust fan, 6-fuel vapor generator, 7-vapor tank, 8-flow regulating valve, 9-catalytic reactor, 10-first electric heater, 11-first heat exchange fan, 12-first temperature sensor, 13-heat exchanger, 14-second heat exchange fan, 15-second temperature sensor, 16-water separator, 17-second shut-off valve, 18-second flame suppressor, 19-second check valve, 20-second electric heater. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] The features and illustrative embodiments of various aspects of the present invention will now be described in detail. Numerous specific details are set forth in the following detailed description to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention. The invention is by no means limited to any specific setups and methods set forth below, but covers any improvements, substitutions, and modifications to structures, methods, and devices without departing from the spirit of the invention. Well-known structures and techniques are not shown in the drawings and the following description to avoid unnecessarily obscuring the invention.

[0025] It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other, and the various embodiments can be referenced and cited in each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] Example 1. As... Figures 1-3As shown, a catalytic inerting system with controllable fuel vapor concentration according to the present invention includes: a fuel tank 1, a first one-way valve 2, a first flame suppressor 3, a first shut-off valve 4, an exhaust fan 5, a fuel vapor generator 6, a vapor tank 7, a flow regulating valve 8, a catalytic reactor 9, a first electric heater 10, a first heat exchange fan 11, a first temperature sensor 12, a heat exchanger 13, a second heat exchange fan 14, a second temperature sensor 15, a water separator 16, a second shut-off valve 17, a second flame suppressor 18, and a second one-way valve 19. The catalytic reactor 9 is provided with a reaction gas inlet, a reaction gas outlet, an electric heating connection port, a cold side inlet, and a cold side outlet; the heat exchanger 13 is provided with a hot side inlet, a hot side outlet, a cold side inlet, and a cold side outlet; the fuel vapor generator 6 is built below the liquid level of the vapor tank 7.

[0027] The outlet of the fuel tank 1 is connected to the inlet of the exhaust fan 5 via a pipe. The outlet of the exhaust fan 5 is connected to the first side of the first three-way pipe via a pipe. The second side of the first three-way pipe is connected to the inlet of the fuel vapor generator 6 via a pipe. The third side of the first three-way pipe is connected to the inlet of the flow regulating valve 8 via a pipe.

[0028] The outlet of the steam tank 7 is connected to the first side of the second three-way pipe via a pipe; the outlet of the flow regulating valve 8 is connected to the second side of the second three-way pipe via a pipe; and the third side of the second three-way pipe is connected to the reaction gas inlet of the catalytic reactor 9 via a pipe.

[0029] The outlet of the first heat exchange fan 11 is connected to the cold side inlet of the catalytic reactor 9 through a pipe, and the cold side outlet of the catalytic reactor 9 is connected to the atmospheric environment through a pipe; the first electric heater 10 is connected to the electric heating port of the catalytic reactor 9 through a cable.

[0030] The reaction gas outlet of the catalytic reactor 9 is connected to the hot side inlet of the heat exchanger 13 via a pipeline;

[0031] The outlet of the second heat exchange fan 14 is connected to the cold side inlet of the heat exchanger 13 through a pipe, and the cold side outlet of the heat exchanger 13 is connected to the atmospheric environment through a pipe.

[0032] The hot side outlet of heat exchanger 13 is connected to the inlet of water separator 16 via a pipe, and the outlet of water separator 16 is connected to the inlet of fuel tank 1 via a pipe.

[0033] A catalytic inerting system with controllable fuel vapor concentration further includes a first one-way valve 2 and a second one-way valve 19. The outlet of the fuel tank 1 is connected to the inlet of the first one-way valve 2 via a pipe, and the outlet of the first one-way valve 2 is connected to the inlet of the exhaust fan 5 via a pipe. The outlet of the water separator 16 is connected to the inlet of the second one-way valve 19 via a pipe, and the outlet of the second one-way valve 19 is connected to the inlet of the fuel tank 1 via a pipe. (The first one-way valve 2 is unidirectional and can prevent high-temperature gas in the catalytic reactor 9 from flowing back into the fuel tank 1 via the exhaust fan 5 in case of a malfunction, thus preventing danger. The second one-way valve 19 is unidirectional and can prevent gas in the fuel tank 1 from flowing back into the water separator 16, thus preventing contamination of the water separator 16.)

[0034] A catalytic inerting system with controllable fuel vapor concentration further includes a first flame suppressor 3 and a second flame suppressor 18. The outlet of the first one-way valve 2 is connected to the inlet of the first flame suppressor 3 via a pipe, and the outlet of the first flame suppressor 3 is connected to the inlet of the exhaust fan 5 via a pipe. The outlet of the water separator 16 is connected to the inlet of the second flame suppressor 18 via a pipe, and the outlet of the second flame suppressor 18 is connected to the inlet of the second one-way valve 19 via a pipe. (The first flame suppressor 3 can prevent flames from entering the fuel tank along the outlet pipe of the fuel tank 1 in case of system failure, such as a fire in the catalytic reactor or the exhaust fan, thus preventing the fuel tank from burning and exploding. The second flame suppressor 18 can also prevent flames from entering the fuel tank along the outlet pipe of the fuel tank 1 in case of system failure, such as a fire in the catalytic reactor or the exhaust fan, thus preventing the fuel tank from burning and exploding.)

[0035] A catalytic inerting system with controllable fuel vapor concentration further includes a first shut-off valve 4 and a first temperature sensor 12. The outlet of the first flame suppressor 3 is connected to the inlet of the first shut-off valve 4 via a pipe, and the outlet of the first shut-off valve 4 is connected to the inlet of the exhaust fan 5 via a pipe. The first temperature sensor 12 is connected to a sampling port on the pipe between the catalytic reactor 9 and the heat exchanger 13. (The first temperature sensor 12 monitors the temperature of the gas at the outlet of the catalytic reactor 9. When the temperature exceeds the safe temperature range, the first shut-off valve 4 is activated, cutting off the connection of the pipeline at the outlet of the fuel tank 1.)

[0036] A catalytic inerting system with controllable fuel vapor concentration further includes a second shut-off valve 17 and a second temperature sensor 15. The outlet of the water separator 16 is connected to the inlet of the second shut-off valve 17 via a pipe, and the outlet of the second shut-off valve 17 is connected to the inlet of the second flame suppressor 18 via a pipe. The second temperature sensor 15 is connected to a sampling port on the pipe between the heat exchanger 13 and the water separator 15. (The second temperature sensor 15 monitors the temperature of the gas at the outlet of the heat exchanger 13. When the temperature exceeds the safe temperature range, the second shut-off valve 17 is activated, cutting off the connection of the pipeline to the fuel tank 1 inlet.)

[0037] Specifically, the fuel vapor generator 6 refers to a device with a porous media structure at the outlet; (the gas entering through the inlet of the fuel vapor generator 6 is discharged through the microporous structure, generating numerous bubbles to promote the release of fuel vapor from the liquid fuel, and then enters the gas phase space of the vapor tank 7 with the gas at the outlet of the fuel vapor generator 6. The fuel vapor generator 6 can make the fuel vapor partial pressure in the gas phase space of the vapor tank 7 approximately reach the saturated vapor pressure, and the fuel vapor concentration reach the maximum value, specifically, it can be increased from the level of hundreds of ppm to the level of thousands of ppm.)

[0038] Specifically, the catalytic reactor 9 refers to an integral reactor coated with a precious metal catalyst, which is equipped with a catalytic reaction channel and a cold edge; (the catalytic reactor 9 is used to catalytically convert fuel vapor and oxygen at the reaction gas inlet into carbon dioxide and water, and can maintain catalytic activity in a low temperature range, with high catalytic reaction efficiency. It also has a cold edge, which has a strong heat exchange capacity).

[0039] The first heat exchange fan 11 and the second heat exchange fan 14 specifically refer to a variable frequency axial flow fan; (its airflow is adjustable. The first heat exchange fan 11 adjusts its airflow based on the temperature information of the gas outlet of the catalytic reactor 9 monitored by the first temperature sensor 12, so that the catalytic reactor 9 operates within a certain temperature range; the second heat exchange fan 14 adjusts its airflow based on the temperature information of the gas outlet of the heat exchanger 13 monitored by the second temperature sensor 15, so that the temperature of the gas outlet of the heat exchanger 13 is within a certain temperature range;)

[0040] The water separator 16 specifically refers to a centrifugal water separator; (it separates free water in the gas at the outlet of heat exchanger 13 through centrifugal force, thereby reducing the water content of the mixed inert gas.)

[0041] The working process of a catalytic inerting system with controllable fuel vapor concentration is as follows: The upper gas phase space of the fuel tank 1 contains a mixture mainly composed of fuel vapor, oxygen, nitrogen, and carbon dioxide. Under the suction and pressurization action of the exhaust fan 5, the mixture enters the flow regulating valve 8 and the steam tank 7 respectively. Part of the mixture entering the steam tank 7 flows out of the steam tank 7 outlet in the form of tiny bubbles after passing through the fuel vapor generator 6. Compared with before entering the steam tank 7, the fuel vapor concentration of this part of the gas can be increased from hundreds of ppm to thousands of ppm, which greatly increases the reactant concentration. The fuel vapor concentration of the other part of the mixture passing through the flow regulating valve 8 remains unchanged at hundreds of ppm. The mixture with high-concentration fuel vapor at the outlet of the steam tank 7 and the mixture with low-concentration fuel vapor at the outlet of the flow regulating valve 8 are further mixed and then enter the catalytic reactor 9. By adjusting the opening of the flow regulating valve 8, the proportion of the mixture entering the steam tank 7 can be controlled, thereby achieving precise adjustment of the fuel vapor concentration of the mixture entering the catalytic reactor 9 within the range of hundreds of ppm to thousands of ppm.

[0042] The mixed gas entering the reaction channel of the catalytic reactor 9 is first heated to a suitable reaction temperature by the first electric heater 10. Under the action of catalysis, it is converted into a mixed inert gas mainly composed of carbon dioxide and water vapor. Then, it enters the hot side of the heat exchanger 13 and exchanges heat with the low-temperature gas on the cold side to cool down. At the same time, a large amount of water vapor is converted into free water. Then, it enters the water separator 16. Under the action of centrifugation, most of the free water is removed. The mixed inert gas after water removal is refilled into the upper gas phase space of the fuel tank 1 to reduce the oxygen concentration in the upper gas phase space of the fuel tank 1, thereby achieving fire prevention and explosion suppression of the fuel tank.

[0043] The opening degree of the flow regulating valve 8 can be adjusted to control the ratio of the mixed gas entering the steam tank 7, thereby achieving precise adjustment of the fuel vapor concentration of the mixed gas entering the catalytic reactor 9 within the range of several hundred ppm to several thousand ppm. The temperature of the mixed inert gas at the outlet of the reaction channel of the catalytic reactor 9 can be controlled below 200℃ by adjusting the flow rate of the cold side gas of the catalytic reactor 9 by the first heat exchange fan 11; the temperature of the mixed inert gas at the outlet of the hot side of the heat exchanger 13 can be controlled within a suitable temperature range by adjusting the flow rate of the cold side gas of the heat exchanger 13 by the second heat exchange fan 13. At the same time, the temperature of the cold side gas and the hot side gas of the heat exchanger 13 after heat exchange can reach 50-80℃, which can be further used for heating the steam tank 7.

[0044] Example 2: In this example, the high-temperature gas from the outlet of heat exchanger 13 is used to heat the steam tank 7, thereby increasing the fuel temperature inside the steam tank 7 and thus increasing the fuel vapor concentration in the gas exiting the steam tank 7 (at 40°C, the fuel vapor concentration can be further increased by 1000-2000 ppm compared to Example 1). Combined with... Figure 2As can be seen, the difference between this embodiment and Example 1 is that the steam oil tank 7 is provided with a gas outlet, a heating inlet, and a heating outlet. The gas outlet of the steam oil tank 7 is connected to the first side of the second three-way pipe through a pipe. The cold side outlet of the heat exchanger 13 is connected to the heating inlet of the steam oil tank 7 through a pipe. The heating outlet of the steam oil tank 7 is connected to the atmospheric environment.

[0045] The working process of this embodiment is as follows: the high-temperature gas from the cold side outlet of the heat exchanger 13 enters the heating inlet of the steam tank 7 through the pipeline, and the high-temperature gas heats the steam tank 7 to increase the fuel temperature inside the steam tank 7. Since the higher fuel temperature corresponds to a higher saturated fuel vapor pressure, the fuel vapor concentration of the gas at the outlet of the steam tank 7 is higher. Compared with embodiment 1, without increasing the number of components or the power consumption of the system, the fuel vapor concentration of the reaction gas entering the catalytic reactor 9 can be further increased, making the adjustable fuel vapor concentration range of the system higher.

[0046] Example 3: In this example, a second electric heater 20 is used to heat the vapor tank 7 to increase the fuel temperature inside the vapor tank 7, thereby increasing the fuel vapor concentration in the outlet gas of the vapor tank 7. Combined with... Figure 3 As can be seen, the difference between this embodiment and Example 1 is that the steam oil tank 7 is provided with a gas outlet and an electric heating connection port. The gas outlet of the steam oil tank 7 is connected to the first side of the second tee pipe through a pipe. The second electric heater 20 is connected to the electric heating connection port of the steam oil tank 7 through a cable.

[0047] The working process of this embodiment is as follows:

[0048] The second electric heater 20 heats the vapor tank 7 to increase the fuel temperature inside the vapor tank 7. Since a higher fuel temperature corresponds to a higher saturated fuel vapor pressure, the fuel vapor concentration of the gas at the outlet of the vapor tank 7 is higher. Compared with Example 1, the fuel vapor concentration of the reaction gas entering the catalytic reactor 9 can be freely adjusted according to the inerting time requirements of the inerting system. This not only makes the adjustable fuel vapor concentration range of the system wider, but also makes the adjustment method more flexible.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should be covered within the protection scope of the present invention.

Claims

1. A catalytic inerting system with controllable fuel vapor concentration, characterized in that, The system includes a fuel tank, with its outlet connected to the inlet of an exhaust fan. The exhaust fan outlet is connected to both the inlet of a flow control valve and the inlet of a vapor tank. Both the flow control valve and the vapor tank outlet are connected to the inlet of the catalytic reactor's reaction gas. The vapor tank inlet is equipped with a fuel vapor generator, which is installed below the liquid level in the vapor tank. The catalytic reactor's reaction gas outlet is connected to the hot-side inlet of a heat exchanger, and the hot-side outlet of the heat exchanger is connected to the inlet of a water separator. The water separator outlet is connected to the fuel tank inlet.

2. The catalytic inerting system with controllable fuel vapor concentration according to claim 1, characterized in that, The steam tank is equipped with a heating channel. The inlet of the heating channel is connected to the cold side outlet of the heat exchanger, and the cold side inlet of the heat exchanger is connected to the outlet of the second heat exchange fan.

3. The catalytic inerting system with controllable fuel vapor concentration according to claim 1, characterized in that, A second electric heater is installed on the steam oil tank.

4. The catalytic inerting system with controllable fuel vapor concentration according to claim 1, characterized in that, The fuel tank is equipped with a first flame suppressor and a second flame suppressor at the outlet and inlet, respectively.

5. The catalytic inerting system with controllable fuel vapor concentration according to claim 1, characterized in that, The catalytic reactor is connected to the first electric heater located at the inlet of the catalytic reactor via an electric heating connection port.

6. The catalytic inerting system with controllable fuel vapor concentration according to claim 1, characterized in that, The catalytic reactor is equipped with a cooling channel, and the cold side inlet of the cooling channel is connected to the first heat exchange fan.

7. A method for operating a catalytic inerting system with controllable fuel vapor concentration as described in any one of claims 1-6, characterized in that, The fuel tank outlet contains a mixture of fuel vapors, which is pressurized by an exhaust fan and then enters the flow control valve and the vapor tank. The mixture entering the vapor tank is then subjected to a fuel vapor generator to increase the fuel vapor concentration. The mixture with increased fuel vapor concentration is then further mixed with the mixture at the outlet of the flow control valve and enters the catalytic reactor. After being processed by the catalytic reactor, a mixed inert gas is generated. The mixed inert gas enters the heat exchanger for cooling and then passes through a water separator to remove water. After water removal, it returns to the fuel tank.

8. The operating method of the catalytic inerting system with controllable fuel vapor concentration according to claim 7, characterized in that, After heat exchange, the gas at 50-80°C from the cold side outlet enters the heating channel of the steam oil tank to heat the steam oil tank.

9. The operating method of the catalytic inerting system with controllable fuel vapor concentration according to claim 7, characterized in that, The steam oil tank is directly heated by a second electric heater.

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