System for collecting and treating volatile organic compounds by using gas holder

Abstract

The invention discloses a system for collecting and treating volatile organic compounds by utilizing a gas holder, which comprises an oil gas collecting system and an oil gas conveying system which are communicated through an oil gas gathering pipeline, the oil gas conveying system is respectively connected with a gas holder recovery system and an emergency discharge system, and the gas holder recovery system is connected with a fuel gas system. The gas cabinet is used for efficiently recovering oil gas, the cost input is small, the occupied area is small, the process and equipment are simple, the process technology is advanced, use is convenient, safety is high, energy consumption is low, and the oil gas recovery efficiency is high.

Description

Technical Field

[0001] This invention belongs to the technical field of treating volatile organic compounds (VOCs) generated during the storage and loading of oil and chemical products that require oil and gas recovery, and specifically relates to a system for collecting and treating volatile organic compounds using a gas holder. Background Technology

[0002] The concentration of oil and gas collected in the tank farm is very low under normal operating conditions. However, drastic changes in concentration often occur due to drastic temperature fluctuations or special operating conditions. Traditional oil and gas treatment methods such as adsorption, absorption, condensation, and membrane separation are not well-suited to these conditions and often fail to meet emission standards. Combustion-based oil and gas treatment requires advanced safety technology, involves significant investment, and consumes a large amount of energy. A single treatment unit with a capacity of 1000 Nm³... 3 The “low-temperature diesel absorption + RTO” oil and gas treatment unit has an investment of nearly 20 million yuan, an operating power of 300kW, and a floor area of ​​approximately 30m×20m. Summary of the Invention

[0003] This invention is proposed to solve the problems existing in the prior art, and its purpose is to provide a system for collecting and treating volatile organic compounds using a gas holder.

[0004] This invention is achieved through the following technical solution: A system for collecting and processing volatile organic compounds using a gas holder includes an oil and gas collection system and an oil and gas transportation system connected by an oil and gas collection pipeline. The oil and gas transportation system is connected to a gas holder recovery system and an emergency release system, respectively. The gas holder recovery system is connected to a fuel gas system. The oil and gas collection system includes at least one oil and gas collection unit, and the oil and gas collection unit includes a storage tank. The storage tank is connected to the oil and gas collection pipeline through an oil and gas collection branch pipe. Starting from the storage tank side, the oil and gas collection branch pipe is sequentially equipped with a No. 1 valve, a No. 1 flame arrester, and an oil and gas branch pipe shut-off valve. A No. 1 pressure gauge is installed between the No. 1 valve and the No. 1 flame arrester. The oil and gas transportation system includes a liquid separator and a blower circulation pipeline. The liquid separator is connected to the oil and gas collection pipeline and to the gas holder recovery system via an oil and gas to gas holder pipeline. One end of the blower circulation pipeline is connected to the oil and gas collection pipeline, and the other end is connected to the oil and gas to gas holder pipeline. The top of the liquid separator is connected to an emergency release system via a liquid separator vent valve and a vent pipeline. The gas holder recovery system includes a low-pressure fuel gas separator, a water washing filter, a gas holder, and a fuel gas compressor unit connected in sequence. The outlet of the gas holder recovery system is connected to the fuel gas system. The low-pressure fuel gas separator is connected to the oil and gas to gas holder pipeline. The emergency relief system includes a vacuum pump and at least one adsorption tank unit. The adsorption tank unit includes an adsorption tank. The inlet of the vacuum pump is connected to the inlet of the adsorption tank through a vacuum pumping pipeline. The outlet of the vacuum pump is connected to the pipeline between the gas supply line shut-off valve and the liquid separator in the tank area through a pipeline. The top of the adsorption tank is connected to the adsorption tank exhaust pipeline through an outlet shut-off valve and a No. II safety valve, respectively. A No. V flame arrester is installed on the adsorption tank exhaust pipeline. The end of the adsorption tank exhaust pipeline is connected to an exhaust chimney.

[0005] In the above technical solution, a breather valve, an emergency pressure relief valve, and a pressure gauge are provided at the top of the storage tank; a bypass is provided at the top of the storage tank, and a nitrogen sealing valve assembly is provided on the bypass; the nitrogen sealing valve assembly includes a nitrogen sealing valve unit and a flow limiting orifice plate unit connected in parallel; the nitrogen sealing valve unit includes two valves connected in series and a nitrogen sealing valve, with the nitrogen sealing valve located between the two valves; the flow limiting orifice plate unit includes two valves connected in series and a flow limiting orifice plate, with the flow limiting orifice plate located between the two valves.

[0006] In the above technical solution, flame arrester No. 2, flame arrester No. 3, and shut-off valve group No. 1 are sequentially installed on the oil and gas degassing tank pipeline from the side of the liquid separator. A valve is installed on the pipeline between flame arrester No. 2 and the liquid separator. Blower No. 1 and blower No. 2 are installed between flame arrester No. 2 and flame arrester No. 3. A valve is installed between blower No. 2 and flame arrester No. 3. A thermometer No. 1, a pressure gauge No. 3, and a flow meter are installed between flame arrester No. 3 and shut-off valve group No. 1. The shut-off valve group consists of a single shut-off valve connected in parallel. The unit consists of a valve assembly. The first shut-off valve unit includes a bus shut-off valve and valves located on both sides of the bus shut-off valve. A nitrogen swivel valve is installed between the valves and the bus shut-off valve. A valve is installed on the inlet side pipeline of the No. I blower, and a No. 5 shut-off valve is installed on the outlet side pipeline. A No. 7 shut-off valve is connected in series between the inlet side pipeline and the outlet side pipeline. A valve is installed on the inlet side pipeline of the No. II blower, and a No. 6 shut-off valve is installed on the outlet side pipeline. An No. 8 shut-off valve is connected in series between the inlet side pipeline and the outlet side pipeline.

[0007] In the above technical solution, one end of the fan circulation pipeline is connected between the gas inlet shut-off valve and the liquid separator in the tank area, and the other end is connected between the No. 3 flame arrester and the bus shut-off valve; a No. 2 shut-off valve group is installed on the fan circulation pipeline. The No. 2 shut-off valve group consists of a No. 2 shut-off valve unit and valves connected in parallel. The No. 2 shut-off valve unit includes a return line shut-off valve and valves installed on both sides of the return line shut-off valve.

[0008] In the above technical solution, the separating tank is connected to the oil and gas collection pipeline, and valves and a gas supply line shut-off valve for the tank area are sequentially installed on the connecting pipeline from the side of the separating tank; oxygen content analyzer No. I, oxygen content analyzer No. II, and oxygen content analyzer No. III are sequentially installed on the side wall of the separating tank from top to bottom; pressure gauge No. II is installed on the top of the separating tank; level gauge No. I is installed on the separating tank; and the bottom of the separating tank is connected to a sludge pump through a pipeline.

[0009] In the above technical solution, the oil and gas transportation system also includes a nitrogen purging pipeline. A valve No. II is installed on the nitrogen purging pipeline. The valve No. II can be connected to a nitrogen swivel valve to purge the gas in the separator tank 21 and pipeline with nitrogen. The pipeline between the flame arrester No. III and the bus shut-off valve is connected to the venting pipeline of the separator tank through a pipeline and a shut-off valve No. 9.

[0010] In the above technical solution, the fuel gas compressor unit includes at least one fuel gas compressor.

[0011] In the above technical solution, the pipeline between the low-pressure fuel gas separator and the oil and gas to gas holder is sequentially equipped with a No. 13 shut-off valve, a No. 4 flame arrester, and a check valve starting from the side of the low-pressure fuel gas separator; the pipeline between the water washing filter and the gas holder is equipped with a gas holder inlet valve; the pipeline between the gas holder and the fuel gas compressor unit is equipped with a shut-off valve; and the pipeline between the fuel gas compressor unit and the fuel gas system is equipped with a shut-off valve.

[0012] In the above technical solution, an adsorption tank shut-off valve and a No. IV pressure gauge are installed on the pipeline between the vacuum pump and the inlet of the adsorption tank; an inlet shut-off valve, a flow meter, a sampling port and a No. VII flame arrester are installed sequentially on the vent pipeline between the bottom of the adsorption tank and the top of the separator, starting from the side of the adsorption tank; the top of the adsorption tank is connected to the main nitrogen pipeline through a nitrogen branch pipeline, and a solenoid valve is installed on the nitrogen branch pipeline.

[0013] In the above technical solution, the top of the separator is connected to the exhaust pipe of the adsorption tank through the separator exhaust pipe. A No. I safety valve and a No. VI flame arrester are installed on the separator exhaust pipe from the separator side. The connection between the separator exhaust pipe and the adsorption tank exhaust pipe is located between the No. V flame arrester and the exhaust chimney.

[0014] The beneficial effects of this invention are: This invention provides a system for collecting and treating volatile organic compounds (VOCs) using a gas holder, transforming the traditional oil and gas treatment concept. It utilizes the gas holder for efficient recovery of oil and gas, which is then used as fuel for the heating furnace, achieving near-zero VOC emissions and comprehensive utilization. This invention features low cost, small footprint, simple process and equipment, advanced technology, ease of use, multiple interlocking protection measures, high safety, low energy consumption, and high oil and gas recovery efficiency. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the present invention.

[0016] in: 1. Oil and gas collection system; 11. Valve No. I; 12. Flame arrester No. I; 13. Oil and gas branch pipe shut-off valve; 14. Pressure gauge No. I; 15. Storage tank; 16. Breather valve; 17. Emergency pressure relief valve; 2. Oil and gas transmission system; 21. Separator; 22. Blower I; 23. Blower II; 24. Sludge pump; 25. Oxygen analyzer I; 26. Oxygen analyzer II; 27. Oxygen analyzer III; 28. Pressure gauge II; 29. ​​Level gauge I; 210. Gas inlet shut-off valve for tank area; 211. Vent valve for separator; 212. Safety valve I; 213. Return line shut-off valve Valve; 214, Flame Arrestor No. II; 215, Shut-off Valve No. 5; 216, Shut-off Valve No. 6; 217, Shut-off Valve No. 7; 218, Shut-off Valve No. 8; 219, Flame Arrestor No. III; 220, Shut-off Valve No. 9; 221, Thermometer No. I; 222, Pressure Gauge No. III; 223, Flow Meter; 224, Main Shut-off Valve; 225, Valve No. II; 226, Valve No. III; 227, Nitrogen Swing Valve; 3. Gas holder recovery system; 31. Gas holder; 32. Fuel gas compressor; 33. Level gauge II; 34. Gas holder inlet valve; 35. Low-pressure fuel gas separator inlet pipeline shut-off valve; 36. Shut-off valve No. 13; 37. Flame arrester No. IV; 38. Check valve; 39. Low-pressure fuel gas separator; 310. Water wash filter; 4. Emergency relief system; 41. Adsorption tank; 42. Vacuum pump; 43. Inlet shut-off valve; 44. Adsorption tank shut-off valve; 45. Outlet shut-off valve; 46. Solenoid valve; 47. Safety valve No. II; 48. Shut-off valve No. 17; 49. Flame arrester No. V; 410. Flame arrester No. VI; 411. Flame arrester No. VII; 412. Exhaust chimney; 413. Thermometer No. II; 414. Pressure gauge No. IV 5. Fuel gas system.

[0017] For those skilled in the art, other related figures can be obtained from the above figures without any creative effort. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0019] like Figure 1 As shown, a system for collecting and treating volatile organic compounds using a gas holder includes an oil and gas collection system, an oil and gas transportation system, a gas holder recovery system, an emergency release system, and a fuel gas system. The oil and gas collection system includes at least one oil and gas collection unit, which includes a storage tank 15. The storage tank 15 is connected to the oil and gas collection pipeline through an oil and gas collection branch pipe. Starting from the storage tank side, the oil and gas collection branch pipe is sequentially equipped with a No. I valve 11, a No. I flame arrester 12, and an oil and gas branch pipe shut-off valve 13. A No. I pressure gauge 14 is installed between the No. I valve 11 and the No. I flame arrester 12. The No. I pressure gauge 14 is interlocked with the oil and gas branch pipe shut-off valve 13. The top of the storage tank 15 is equipped with a breather valve 16, an emergency pressure relief valve 17 and a pressure gauge; A bypass is provided at the top of the storage tank 15, and a nitrogen sealing valve assembly is provided on the bypass; the nitrogen sealing valve assembly includes a nitrogen sealing valve unit and a flow limiting orifice plate unit connected in parallel; the nitrogen sealing valve unit includes two valves connected in series and a nitrogen sealing valve, and the nitrogen sealing valve is located between the two valves; the flow limiting orifice plate unit includes two valves connected in series and a flow limiting orifice plate, and the flow limiting orifice plate is located between the two valves; The No. I flame arrester 12 is an explosion-proof flame arrester; The oil and gas collection system is connected to the oil and gas transportation system through an oil and gas collection pipeline. The oil and gas transportation system includes a liquid separator 21 and a blower circulation pipeline. The middle part of the liquid separator 21 is connected to the oil and gas collection pipeline, and the upper part of the liquid separator 21 is connected to the gas holder recovery system through the oil and gas to gas holder pipeline. One end of the blower circulation pipeline is connected to the oil and gas collection pipeline, and the other end is connected to the oil and gas to gas holder pipeline. Starting from the liquid separator side, flame arrester 214 (No. II), flame arrester 219 (No. III), and shut-off valve group 1 are sequentially installed on the oil and gas separation tank pipeline. Valves are installed on the pipeline between flame arrester 214 (No. II) and liquid separator 21. Blower 22 (No. I) and blower 23 (No. II) are installed between flame arrester 214 (No. II) and flame arrester 219 (No. III). Valves are installed between blower 23 (No. II) and flame arrester 219 (No. III). Thermometer 221 (No. I), pressure gauge 222 (No. III), and flow meter 223 are installed between flame arrester 219 (No. III) and shut-off valve group 1. Shut-off valve group 1 consists of shut-off valve unit 1 and valves connected in parallel. Shut-off valve unit 1 includes main shut-off valve 224 and valves 226 located on both sides of main shut-off valve 224. Nitrogen swivel valve 227 is installed between valve 226 and main shut-off valve 224. A valve is installed on the inlet side pipe of blower I 22, and a No. 5 shut-off valve 215 is installed on the outlet side pipe. A No. 7 shut-off valve 217 is connected in series between the inlet side pipe and the outlet side pipe. A valve is installed on the inlet side pipe of blower II 23, and a No. 6 shut-off valve 216 is installed on the outlet side pipe. An No. 8 shut-off valve 218 is connected in series between the inlet side pipe and the outlet side pipe. One end of the blower circulation pipeline is connected between the gas inlet shut-off valve 210 and the liquid separator 21 in the tank area, and the other end is connected between the No. III flame arrester 219 and the bus shut-off valve 224; a No. 2 shut-off valve group is installed on the blower circulation pipeline. The No. 2 shut-off valve group consists of a No. 2 shut-off valve unit and valves connected in parallel. The No. 2 shut-off valve unit includes a return line shut-off valve 213 and valves located on both sides of the return line shut-off valve 213. The liquid separator 21 is connected to the oil and gas collection pipeline, and valves and gas supply line shut-off valves 210 for the tank area are installed sequentially on the connecting pipeline from the liquid separator side. The sidewall of the separating tank 21 is equipped with oxygen content analyzer I 25, oxygen content analyzer II 26 and oxygen content analyzer III 27 from top to bottom; pressure gauge II 28 is installed on the top of the separating tank 21. The liquid separator 21 is equipped with a No. I level gauge 29; The bottom of the separating tank 21 is connected to the sludge pump 24 via a pipeline; The top of the separator 21 is connected to the emergency relief system via a separator vent valve 211 and a vent pipeline. The oil and gas transportation system also includes a nitrogen purging pipeline. A valve 225 is installed on the nitrogen purging pipeline. The valve 225 can be connected to a nitrogen swivel valve 227 to purge the gas in the separator 21 and pipeline with nitrogen. The pipeline between the No. III flame arrester 219 and the bus shut-off valve 224 is connected to the vent pipeline of the separator 21 via a pipeline and the No. 9 shut-off valve 220. The gas holder recovery system includes a low-pressure fuel gas separator 39, a water filter 310, a gas holder 31, and a fuel gas compressor unit connected in sequence. The outlet of the gas holder recovery system is connected to the fuel gas system 5. The fuel gas compressor unit includes at least one fuel gas compressor 32. The low-pressure fuel gas separator 39 is connected to the oil and gas to gas holder pipeline, and a No. 13 shut-off valve 36, a No. IV flame arrester 37, and a check valve 38 are installed in sequence on the pipeline from the low-pressure fuel gas separator side. A gas holder inlet valve 34 is installed on the pipeline between the water filter 310 and the gas holder 31. A shut-off valve is installed on the pipeline between the gas holder 31 and the fuel gas compressor unit. A shut-off valve is installed on the pipeline between the fuel gas compressor unit and the fuel gas system 5. The gas holder 31 is equipped with a No. II level gauge 33 and a pressure gauge; The inlet of the low-pressure fuel gas separator 39 is connected to the low-pressure venting main pipe of the flare, and a low-pressure fuel gas separator inlet pipe shut-off valve 35 is installed on the connecting pipe. The emergency relief system includes a vacuum pump 42 and at least one adsorption tank unit, the adsorption tank unit including an adsorption tank 41. The inlet of vacuum pump 42 is connected to the inlet of adsorption tank 41 through a vacuum pumping pipeline, and the outlet of vacuum pump 42 is connected to the pipeline between the gas supply line shut-off valve 210 and the liquid separator 21 in the tank area through a pipeline; an adsorption tank shut-off valve 44 and pressure gauge IV 414 are installed on the pipeline between vacuum pump 42 and the inlet of adsorption tank 41. An inlet shut-off valve 43, a flow meter, a sampling port, and a flame arrester 411 are sequentially installed on the vent pipe between the bottom of the adsorption tank 41 and the top of the separator 21, starting from the side of the adsorption tank. The top of the adsorption tank 41 is connected to the adsorption tank exhaust pipe through the outlet shut-off valve 45 and the No. II safety valve 47 respectively. A No. V flame arrester 49 is installed on the adsorption tank exhaust pipe, and the end of the adsorption tank exhaust pipe is connected to the exhaust chimney 412. The top of the adsorption tank 41 is connected to the main nitrogen pipeline via a nitrogen branch pipeline, and a solenoid valve 46 is installed on the nitrogen branch pipeline. The top of the separator 21 is connected to the exhaust pipe of the adsorption tank through the separator exhaust pipe. A No. I safety valve 212 and a No. VI flame arrester 410 are installed on the separator exhaust pipe from the separator side. The connection between the separator exhaust pipe and the adsorption tank exhaust pipe is located between the No. V flame arrester 49 and the exhaust chimney 412. The adsorption tank 41 is equipped with a No. II thermometer 413.

[0020] When multiple adsorption tank units are set up, they are connected in parallel.

[0021] The fuel gas system includes a fuel gas pipeline network and downstream gas-using equipment.

[0022] The oil and gas recovery process of the system includes the following steps: 1. The oil and gas collection of the storage tank adopts a single tank single control scheme. A pneumatic shut-off valve is installed downstream of the explosion-proof flame arrester on the oil and gas collection branch pipe of each storage tank, and is interlocked with the pressure transmitter of the oil and gas collection branch pipe.

[0023] When the pressure in the storage tank rises to a certain value, the valve is opened to release oil and gas; when the pressure in the storage tank drops to a certain value, the valve is closed. 2. After the oil and gas in the storage tank are collected and aggregated, they first enter the separator, and then are pressurized and transported to the gas holder by a blower. The separator is equipped with an oxygen content analyzer and a pressure gauge. When the oxygen content is <2% and the pressure in the separator reaches a certain value, the oil and gas to pipeline main bus shut-off valve is interlocked and the blower is adjusted to the rated frequency to exhaust gas into the gas holder. 3. When the oxygen content in the separator exceeds 2%, the interlock shut-off valve for the oil and gas supply line from the tank area is closed, the blower is shut off, and the main oil and gas supply line to the pipeline is shut off to prevent the oxygen content of the oil and gas entering the gas holder from exceeding the standard. At the same time, the vent valve of the separator is opened, and the gas in the separator and pipeline is purged with nitrogen. The excess oxygen oil and gas in the separator is discharged to the adsorption tank for adsorption through the vent line on the top of the tank to prevent the volatile organic compounds in the tail gas from exceeding the standard when directly discharged into the atmosphere. The adsorbed vent gas is discharged into the atmosphere. When the oil and gas in the tank area are normally transported to the gas holder, the activated carbon is desorbed by a vacuum pump, and the regeneration gas enters the inlet of the oil and gas separator and is sent to the gas holder for recovery together with the oil and gas in the tank area. IV. After being pressurized by a blower, the oil and gas are transported from the pipeline to the gas holder. Inside the gas holder, they are mixed with other high-concentration fuel gases discharged into the gas holder to ensure that the calorific value of the gas in the gas holder meets the combustion requirements, while the oxygen content is <2% to ensure that the gas in the system will not generate an explosion risk. V. The fuel gas in the gas holder is pressurized by the fuel gas compressor and transported to downstream gas-using equipment such as heating furnaces through the fuel gas pipeline network. Volatile organic compounds (VOCs) are burned together with the fuel gas and converted into water and carbon dioxide, thus achieving compliant VOC emissions. When the gas holder level reaches the high-high value, the gas holder inlet valve is interlocked and shut off, and the unit's vent gas is discharged to the flare; the tank area oil and gas inlet gas holder line shut-off valve is interlocked and shut off, and the blower outlet to the adsorption tank shut-off valve is interlocked and turned on. The oil and gas in the tank area are briefly adsorbed by the activated carbon adsorption tank before being discharged into the atmosphere.

[0024] Example 1 and Figure 1 Based on this, the method of using the present invention is as follows: When liquid is introduced into storage tank 15 or the temperature rises rapidly, the oil and gas pressure at the top of the tank increases. When pressure gauge 14 reaches a certain value, the oil and gas branch pipe shut-off valve 13 is opened, valve 11 is in the open state, and flame arrester 12 is in normal working condition. When pressure gauge 14 drops to a certain value, the oil and gas branch pipe shut-off valve 13 is closed.

[0025] After the oil and gas in the storage tank are collected and aggregated, they first enter the separator 21, and then are pressurized and transported to the gas holder 31 by blowers 22 (No. I) and 23 (No. II). Separator 21 is equipped with three oxygen content analyzers 25, 26, and 27, and pressure gauge 28 (No. II). When all three oxygen content analyzers 25, 26, and 27 measure an oxygen content <2%, and pressure gauge 28 reaches a certain value, the oil and gas pipeline main line shut-off valve 224 is interlocked open, and the blower return line shut-off valve 213 is closed. Blower 23 is adjusted to its rated frequency; when pressure gauge 28 continues to rise to a certain value, blower 22 is gradually adjusted from low frequency to its rated frequency; when pressure gauge 28 drops to a certain value, blower 23 is gradually adjusted to low frequency, and blower 22 is shut off; when pressure gauge 28 continues to drop to a certain value, blower 23 is adjusted to its lowest frequency, the blower's return line shut-off valve 213 is interlocked open, and the main line shut-off valve 224 for oil and gas to the pipeline is closed. At low pressure, the blower circulates oil and gas; at high pressure, it discharges to the gas holder, and the blower remains operational.

[0026] Three oxygen analyzers (25, 26, and 27) are interlocked in a three-out-of-two control configuration. When any two oxygen analyzers measure an oxygen content exceeding 2%, the interlock closes the gas supply line shut-off valve 210 from the tank area, shuts off blowers 22 and 23 (both No. 1 and No. 23), and shuts off the main gas supply line shut-off valve 224. The vent valve 211 of the separator is opened, as are shut-off valves 217 and 218 (between the inlet and outlet of the blowers), the return line shut-off valve 213 of the blowers, and the inlet and outlet shut-off valves 43 and 45 of the adsorption tank 41. Valve 225 is connected to the nitrogen purging valve 227, and nitrogen is used to purge the gas in the separator 21 and pipelines. The excess oxygen-laden oil and gas in the separator 21 is discharged to the adsorption tank 41 for adsorption through the vent pipe on the tank top. The adsorbed oil and gas is then discharged into the atmosphere through the exhaust chimney 412. When oil and gas from the tank farm are being normally transported to the gas holder 31, activated carbon undergoes desorption. The adsorption tank shut-off valve 44 is opened, and the vacuum pump 42 is activated. Regeneration gas enters the inlet of the oil-gas separator 21 and is sent to the gas holder 31 for recovery along with the oil and gas from the tank farm. The frequency of the vacuum pump 42 is controlled by pressure gauge IV 414. When pressure gauge IV 414 reaches a certain vacuum pressure, the vacuum pump 42 is shut off. After the adsorption tank 41 is evacuated, the solenoid valve 46 is opened to replenish nitrogen. If thermometer II 413 exceeds a certain value, the inlet shut-off valve 43 of the adsorption tank 41 is closed, and shut-off valve 17 48 is opened, allowing the oil and gas to be directly discharged into the atmosphere through the exhaust chimney 46.

[0027] When the oxygen content of the oxygen analyzer that exceeded the standard dropped to 1.9%, continue purging for 10 minutes, then close the vent valve 211 of the separator, close the No. 7 shut-off valve 217 and No. 8 shut-off valve 218 on the inlet and outlet cross lines of the blower, close the return line shut-off valve 213 of the blower, and open the gas inlet line shut-off valve 210 of the tank area.

[0028] When pressure gauge 222 rises to a certain value, or when thermometer 221 reaches a certain value, thermometer 221 and blower 23 stop operating, and interlock shut off the main gas shut-off valve 224 to the pipeline network, shut off the blower's shut-off valves 215 and 216, and shut off the blower's return line shut-off valve 213.

[0029] After being pressurized by blowers 22 (No. 1) and 23 (No. 23), the oil and gas are transported from the pipeline to the gas holder 31, and then connected to the shut-off valve 35 of the low-pressure fuel gas separator inlet pipeline. When the gas holder 31 reaches the high alarm value, the two fuel gas compressors 32 are started to gradually lower the gas holder level, ensuring stable operation of the gas holder. When the gas holder level reaches the very high value, the gas holder inlet valve 34 is interlocked and shut off, and the unit's vent gas is discharged to the flare; the tank area oil and gas inlet gas holder shut-off valve 38 is interlocked and shut off, and the blower outlet to the adsorption tank's No. 9 shut-off valve 220 is interlocked and opened, allowing the tank area oil and gas to be briefly adsorbed by the activated carbon adsorption tank 41 before being discharged into the atmosphere.

[0030] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A system for collecting and treating volatile organic compounds using a gas cabinet, characterized by: The oil and gas collection system and the oil and gas delivery system are connected through an oil and gas collecting pipeline, the oil and gas delivery system is connected with a gas tank recovery system and an emergency relief system respectively, and the gas tank recovery system is connected with a fuel gas system; The oil and gas collection system comprises at least one oil and gas collection unit, and the oil and gas collection unit comprises a storage tank (15) connected with the oil and gas collecting pipeline through an oil and gas collection branch pipe, wherein a No. 1 valve (11), a No. 1 flame arrester (12) and an oil and gas branch pipe cut-off valve (13) are arranged on the oil and gas collection branch pipe in sequence from the side of the storage tank; a No. 1 pressure gauge (14) is arranged between the No. 1 valve (11) and the No. 1 flame arrester (12); The oil and gas delivery system comprises a separator tank (21) and a fan circulating pipeline, the separator tank (21) is connected with the oil and gas collecting pipeline, the separator tank (21) is connected with the gas tank recovery system through an oil and gas tank pipeline, one end of the fan circulating pipeline is connected with the oil and gas collecting pipeline, and the other end is connected with the oil and gas tank pipeline; the separator tank (21) is connected with the emergency relief system through a separator tank vent valve (211) and a vent pipeline at the top of the separator tank (21); The gas tank recovery system comprises a low-pressure fuel gas separator tank (39), a water-washing filter (310), a gas tank (31) and a fuel gas compressor set connected in sequence, and the outlet of the gas tank recovery system is connected with the fuel gas system (5); the low-pressure fuel gas separator tank (39) is connected with the oil and gas tank pipeline; The emergency relief system comprises a vacuum pump (42) and at least one adsorption tank unit, the adsorption tank unit comprises an adsorption tank (41), the inlet of the vacuum pump (42) is connected with the inlet of the adsorption tank (41) through a vacuumizing pipeline; the outlet of the vacuum pump (42) is connected with a pipeline between a tank area incoming gas line cut-off valve (210) and the separator tank (21) through a pipeline; the top of the adsorption tank (41) is connected with an adsorption tank exhaust pipeline through an outlet cut-off valve (45) and a No. 2 safety valve (47) respectively, a No. 5 flame arrester (49) is arranged on the adsorption tank exhaust pipeline, and the end of the adsorption tank exhaust pipeline is connected with an exhaust chimney (412).

2. The system for collecting and treating volatile organic compounds with a gas cabinet of claim 1, wherein: A breather valve (16), an emergency relief valve (17) and a pressure gauge are arranged at the top of the storage tank (15); a bypass is arranged at the top of the storage tank (15), and a nitrogen sealing valve group is arranged on the bypass; the nitrogen sealing valve group comprises a nitrogen sealing valve unit and a flow limiting orifice plate unit connected in parallel; the nitrogen sealing valve unit comprises two valves and a nitrogen sealing valve connected in series, and the nitrogen sealing valve is arranged between the two valves; the flow limiting orifice plate unit comprises two valves and a flow limiting orifice plate connected in series, and the flow limiting orifice plate is arranged between the two valves.

3. The system for collecting and treating volatile organic compounds with a gas cabinet of claim 1, wherein: The oil and gas degassing cabinet pipeline is sequentially provided with a No. 2 fire arrester (214), a No. 3 fire arrester (219) and a No. 1 cut-off valve group from the side of the liquid separation tank; a valve is arranged on the pipeline between the No. 2 fire arrester (214) and the liquid separation tank (21), a No. 1 air blower (22) and a No. 2 air blower (23) are arranged between the No. 2 fire arrester (214) and the No. 3 fire arrester (219), a valve is arranged between the No. 2 air blower (23) and the No. 3 fire arrester (219), a No. 1 thermometer (221), a No. 3 pressure gauge (222) and a flowmeter (223) are arranged between the No. 3 fire arrester (219) and the No. 1 cut-off valve group, the No. 1 cut-off valve group is composed of a No. 1 cut-off valve unit and a valve connected in parallel, the No. 1 cut-off valve unit comprises a bus cut-off valve (224) and valves (226) arranged on both sides of the bus cut-off valve (224); a nitrogen head valve (227) is arranged between the valve (226) and the bus cut-off valve (224); a valve is arranged on the air inlet side pipeline of the No. 1 air blower (22), a No. 5 cut-off valve (215) is arranged on the air outlet side pipeline, and a No. 7 cut-off valve (217) is connected in series between the air inlet side pipeline and the air outlet side pipeline; a valve is arranged on the air inlet side pipeline of the No. 2 air blower (23), a No. 6 cut-off valve (216) is arranged on the air outlet side pipeline, and a No. 8 cut-off valve (218) is connected in series between the air inlet side pipeline and the air outlet side pipeline.

4. The system for collecting and treating volatile organic compounds with a gas cabinet of claim 1, wherein: One end of the fan circulating pipeline is connected between the tank area gas line cut-off valve (210) and the liquid separation tank (21), and the other end is connected between the No. 3 fire arrester (219) and the bus cut-off valve (224); a No. 2 cut-off valve group is arranged on the fan circulating pipeline, the No. 2 cut-off valve group is composed of a No. 2 cut-off valve unit and a valve connected in parallel, and the No. 2 cut-off valve unit comprises a backflow line cut-off valve (213) and valves arranged on both sides of the backflow line cut-off valve (213).

5. The system for collecting and treating volatile organic compounds with a gas cabinet of claim 1, wherein: The liquid separation tank (21) is communicated with the oil and gas collecting pipeline, and a valve and the tank area gas line cut-off valve (210) are sequentially arranged on the communication pipeline from the side of the liquid separation tank; a No. 1 oxygen content analyzer (25), a No. 2 oxygen content analyzer (26) and a No. 3 oxygen content analyzer (27) are sequentially arranged on the side wall of the liquid separation tank (21) from top to bottom; a No. 2 pressure gauge (28) is arranged on the top of the liquid separation tank (21); a No. 1 liquid level meter (29) is arranged on the liquid separation tank (21); and a dirty oil pump (24) is connected to the bottom of the liquid separation tank (21) through a pipeline.

6. The system for collecting and treating volatile organic compounds with a gas cabinet of claim 1, wherein: The oil and gas conveying system further comprises a nitrogen purging pipeline, a No. 2 valve (225) is arranged on the nitrogen purging pipeline, the No. 2 valve (225) can be connected with the nitrogen head valve (227) to realize purging of the liquid separation tank 21 and gas in the pipeline with nitrogen; the pipeline between the No. 3 fire arrester (219) and the bus cut-off valve (224) is communicated with the vent pipeline of the liquid separation tank (21) through a pipeline and a No. 9 cut-off valve (220).

7. The system for collecting and treating volatile organic compounds with a gas cabinet of claim 1, wherein: The fuel gas compressor set comprises at least one fuel gas compressor (32).

8. The system for collecting and treating volatile organic compounds with a gas cabinet of claim 1, wherein: The low-pressure fuel gas distribution tank (39) is provided with a No. 13 shut-off valve (36), a No. IV flame arrester (37) and a check valve (38) in sequence from the low-pressure fuel gas distribution tank side to the pipeline between the oil gas deaerator tank pipeline; a gas tank inlet valve (34) is arranged on the pipeline between the water washing filter (310) and the gas tank (31); a shut-off valve is arranged on the pipeline between the gas tank (31) and the fuel gas compressor set; a shut-off valve is arranged on the pipeline between the fuel gas compressor set and the fuel gas system (5).

9. The system for collecting and treating volatile organic compounds with a gas cabinet of claim 1, wherein: The vacuum pump (42) is provided with a No. IV pressure gauge (414) and an adsorption tank shut-off valve (44) on the pipeline between the adsorption tank (41) outlet; an inlet shut-off valve (43), a flowmeter, a sampling port and a No. VII flame arrester (411) are arranged in sequence from the adsorption tank side on the venting pipeline between the bottom of the adsorption tank (41) and the top of the distribution tank (21); the top of the adsorption tank (41) is connected to the nitrogen main pipeline through a nitrogen branch pipeline, and an electromagnetic valve (46) is arranged on the nitrogen branch pipeline.

10. The system for collecting and treating volatile organic compounds with a gas cabinet of claim 1, wherein: The top of the distribution tank (21) is connected to the adsorption tank exhaust pipeline through a distribution tank exhaust pipeline, a No. I safety valve (212) and a No. VI flame arrester (410) are arranged on the distribution tank exhaust pipeline from the distribution tank side, and the connection between the distribution tank exhaust pipeline and the adsorption tank exhaust pipeline is arranged between a No. V flame arrester (49) and an exhaust chimney (412).

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