A system for recycling of vent gas from oil and gas field production processes

Abstract

This invention relates to a system for recovering and utilizing exhaust gases from oil and gas field production processes, comprising a gas-liquid separator unit, an exhaust gas collection unit, a compressor unit, a scrubbing tank unit, a flare separator, and a controller. The gas-liquid separator unit separates crude oil into gas and liquid phases. The gas phase outlet of the gas-liquid separator unit is connected to the inlet of the scrubbing tank unit, and the outlet of the scrubbing tank unit is connected to both the compressor unit and the flare separator. The inlet of the exhaust gas collection unit is connected to both the gas phase outlet of the gas-liquid separator unit and the inlet of the compressor unit, and the outlet of the exhaust gas collection unit is connected to the inlet of the scrubbing tank unit. The control valve of the exhaust gas collection unit is connected to the controller. This invention addresses the problems of unstable and low-pressure exhaust gases by using a low-pressure compressor operating continuously and a low-pressure intake pressurization configuration; it addresses the problem of intermittent exhaust gas emissions by operating continuously; and it addresses the problem of small exhaust gas volumes by using a large production gas volume.

Description

Technical Field

[0001] This invention relates to the technical field of marine engineering, specifically to a system for recovering and utilizing emissions from oil and gas field production processes. Background Technology

[0002] Closed crude oil and natural gas processing systems typically include pressure regulating valves and pressure relief valves at key points such as separation and pressurization. When process pressure fluctuates, the opening of the pressure regulating valve is adjusted to maintain stable process pressure. During equipment maintenance, the pressure relief valve is opened to release combustible hydrocarbons from the system. These valves are indispensable for stabilizing production process operating pressure and ensuring operational safety during maintenance, but they can cause intermittent or even continuous emissions of associated gases.

[0003] With the energy industry placing increasing emphasis on energy conservation and emission reduction, pressure regulating and depressurizing exhaust gases (hereinafter referred to as "emission gases") must be recovered and utilized according to the principle of "recovering as much as possible." Offshore oil and gas fields emit approximately 3000-10000 Sm³ of exhaust gases per day. 3 / d represents a major material loss in offshore oil and gas fields, accompanied by environmental problems such as continuous burning of flare flames and black smoke from the flare. Therefore, economically and effectively recovering emitted gas is an important way to save energy, reduce emissions, and improve the production capacity of oil fields.

[0004] Currently, relevant literature and standards have paid attention to the problem of low-pressure gas recovery. The prevention and control measures focus on closed flare systems, which connect compression facilities to the gas phase outlet of the flare separator to recover the vented gas. However, due to the addition of flare gas compressors and the frequent start-stop of the compressors, closed flare systems have high investment costs, large footprints, and complex operation and maintenance. They are not economically viable for use on offshore platforms and are difficult to promote.

[0005] In summary, there is an urgent need for a system for recovering and utilizing gases emitted during oil and gas field production processes. Summary of the Invention

[0006] The purpose of this invention is to provide a system for recovering and utilizing gas emitted during oil and gas field production processes, in order to solve the problem of poor recovery and utilization of associated gas in offshore oil and gas fields mentioned in the background art.

[0007] To achieve the above objectives, this invention provides a system for recovering and utilizing emissions from oil and gas field production processes. The technical solution adopted is as follows:

[0008] A system for recovering and utilizing exhaust gases from oil and gas field production processes includes a gas-liquid separator unit, an exhaust gas collection unit, a compressor unit, a gas scrubbing tank unit, a flare distribution tank, and a controller.

[0009] The gas-liquid separator unit is used to separate crude oil into gas and liquid phases. The gas phase outlet of the gas-liquid separator unit is connected to the inlet of the gas scrubbing tank unit, and the outlet of the gas scrubbing tank unit is connected to the compressor unit and the flare separator tank, respectively.

[0010] The inlet of the exhaust gas merging unit is connected to the gas phase outlet of the gas-liquid separator unit and the inlet of the compressor unit, respectively. The outlet of the exhaust gas merging unit is connected to the inlet of the scrubbing tank unit. The control valve of the exhaust gas merging unit is connected to the controller.

[0011] Preferably, the oil and gas field production process emission gas recovery and utilization system further includes a pressure stabilization unit. The pressure stabilization unit includes a first pressure detection transmitter, a frequency converter, and a gas scrubbing tank pressure regulating valve. The gas scrubbing tank pressure regulating valve is provided between the gas outlet of the gas scrubbing tank unit and the flare separator. The first pressure detection transmitter is used to measure the pressure inside the gas scrubbing tank unit. The first pressure detection transmitter, the frequency converter, and the gas scrubbing tank pressure regulating valve are respectively connected to the controller. The frequency converter is connected to the compressor unit.

[0012] Preferably, the oil and gas field production process emission gas recovery and utilization system further includes an associated gas cooler, which is installed at the inlet of the gas scrubbing tank unit, and the inlet of the associated gas cooler is connected to the gas phase outlet of the emission gas merging unit and the gas-liquid separator unit respectively.

[0013] Preferably, in the oil and gas field production process emission gas recovery and utilization system, the compressor unit includes a low-pressure compressor, a medium-pressure compressor, and a high-pressure compressor, which are connected in sequence. The gas scrubbing tank unit is provided at the air inlet of the low-pressure compressor, the air inlet of the medium-pressure compressor, and the air inlet of the high-pressure compressor. The medium-pressure compressor is connected to the frequency converter.

[0014] The oil and gas field production process emission gas recovery and utilization system, preferably, the gas scrubbing tank unit includes a low-pressure compressor inlet gas scrubbing tank, a medium-pressure compressor inlet gas scrubbing tank and a high-pressure compressor inlet gas scrubbing tank, the low-pressure compressor inlet gas scrubbing tank, the low-pressure compressor, the medium-pressure compressor inlet gas scrubbing tank, the medium-pressure compressor, the high-pressure compressor inlet gas scrubbing tank and the high-pressure compressor are connected in sequence;

[0015] The associated gas cooler is provided at the inlet of the low-pressure compressor inlet scrubbing tank;

[0016] The air inlet of the medium-pressure compressor inlet scrubbing tank is also connected to the gas-liquid separator unit;

[0017] The first pressure detection transmitter is provided on the inlet gas tank of the low-pressure compressor. The outlet of the inlet gas tank of the low-pressure compressor is also connected to the flare liquid separator. The gas tank pressure regulating valve is provided between the outlet of the inlet gas tank of the low-pressure compressor and the flare liquid separator.

[0018] The oil and gas field production process emission gas recovery and utilization system, preferably, the emission gas collection unit includes an emission gas pipe assembly, a pressure relief valve assembly, and a regulating valve assembly;

[0019] The exhaust pipe assembly includes a first exhaust pipe, a second exhaust pipe, and a third exhaust pipe;

[0020] The pressure relief valve assembly includes a first pressure relief valve, a second pressure relief valve, and a third pressure relief valve;

[0021] The regulating valve assembly includes a first regulating valve, a second regulating valve, and a third regulating valve;

[0022] The first exhaust pipe is connected to the gas phase outlet of the gas-liquid separator unit, and the first pressure relief valve and the first regulating valve are connected in parallel on the first exhaust pipe.

[0023] The second discharge pipe is connected to the inlet end of the medium-pressure compressor, and the second pressure relief valve and the second regulating valve are connected in parallel on the second discharge pipe;

[0024] The third exhaust pipe is connected to the intake end of the high-pressure compressor, and the third pressure relief valve and the third regulating valve are connected in parallel on the third exhaust pipe;

[0025] The outlet ends of the first exhaust pipe, the second exhaust pipe, and the third exhaust pipe are all connected to the associated gas cooler.

[0026] The first pressure relief valve, the first regulating valve, the second pressure relief valve, the second regulating valve, the third pressure relief valve, and the third regulating valve are respectively connected to the controller.

[0027] Preferably, in the oil and gas field production process emission gas recovery and utilization system, the gas-liquid separator unit is equipped with a second pressure detection transmitter, which is connected to the controller.

[0028] Preferably, in the oil and gas field production process emission gas recovery and utilization system, a third pressure detection transmitter is provided on the inlet scrubbing tank of the medium-pressure compressor, and the third pressure detection transmitter is connected to the controller.

[0029] Preferably, in the oil and gas field production process emission gas recovery and utilization system, a fourth pressure detection transmitter is provided on the inlet scrubbing tank of the high-pressure compressor, and the fourth pressure detection transmitter is connected to the controller.

[0030] The oil and gas field production process emission gas recovery and utilization system, preferably, includes a gas-liquid separator unit comprising a production separator and a low-pressure separator. The liquid phase outlet of the production separator is connected to the liquid phase inlet of the low-pressure separator. The gas phase outlet of the production separator is connected to the first emission gas pipe and the inlet of the medium-pressure compressor inlet scrubbing tank, respectively. The gas phase outlet of the low-pressure separator is connected to the associated gas cooler.

[0031] The present invention has the following advantages due to the adoption of the above technical solutions:

[0032] Economic efficiency: This invention utilizes the platform's existing low-pressure compression system to recover emissions from the production process, achieving the recovery and utilization of oil and gas field emissions only through piping connections, access modifications, and instrumentation signal access.

[0033] Stability: This invention patent utilizes the associated gas from the low-pressure separator to merge and discharge the associated gas, using the larger gas to drive the smaller gas, thus ensuring the continuous and stable operation of the associated gas recovery compressor (i.e., the low-pressure compressor) and avoiding frequent start-ups and shutdowns of the associated gas recovery compressor.

[0034] Automation: This invention patent automatically recovers most of the pressure regulation and maintenance emissions from the production process, minimizing associated gas releases from oil and gas field production platforms.

[0035] This invention utilizes the associated gas emitted from pressure regulating valves and pressure relief valves in the production process of existing low-pressure compressors on offshore oil and gas platforms. It collects the exhaust gas from various pressure control points during production and merges it into the gas phase outlet of a low-pressure separator. This gas is then pressurized together with the associated gas from the low-pressure separator for further processing in the next step. The continuous operation of the low-pressure compressor and the low-pressure intake pressurization configuration address the issues of unstable exhaust gas and low pressure. Continuous operation solves the problem of intermittent exhaust gas emission, and the large volume of production gas is compatible with the small volume of exhaust gas. This achieves stable recovery and utilization of exhaust gas, significantly reducing the number of pressure regulating valves and pressure relief valves emitted to the flare and the amount of gas emitted from the flare, thereby increasing the economic benefits of the oilfield. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the system of the present invention.

[0037] In the picture:

[0038] 1. Production separator; 2. Low-pressure separator;

[0039] 3-1, First pressure relief valve; 3-2, Second pressure relief valve; 3-3, Third pressure relief valve;

[0040] 4-1, First regulating valve; 4-2, Second regulating valve; 4-3, Third regulating valve; 4-4, Fourth regulating valve;

[0041] 5-1. First exhaust pipe; 5-2. Second exhaust pipe; 5-3. Third exhaust pipe;

[0042] 6-1. Low-pressure compressor; 6-2. Medium-pressure compressor; 6-3. High-pressure compressor;

[0043] 7. Associated gas cooler; 8-1. Low-pressure compressor inlet scrubbing tank; 8-2. Medium-pressure compressor inlet scrubbing tank;

[0044] 8-3, High-pressure compressor inlet scrubbing tank; 9-1, First pressure detection transmitter; 10, Variable frequency controller;

[0045] 11. Pressure regulating valve for the gas scrubber; 12. Flare separator; 9-2. Second pressure transmitter;

[0046] 9-3, Third pressure transmitter; 9-4, Fourth pressure transmitter; 13, Main pipeline;

[0047] 14-1, First level transmitter; 14-2, Second level transmitter; 15, Transfer pump. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0049] In the description of this invention, it should be noted that the terms "first," "second," "third," and "fourth," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the system or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0050] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "set up" and "equipped with" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0051] This invention provides a system for recovering and utilizing exhaust gases from oil and gas field production processes. The invention includes a gas-liquid separator unit, an exhaust gas collection unit, a compressor unit, a scrubbing tank unit, a flare separator, and a controller. The gas-liquid separator unit is used for gas-liquid separation of crude oil. The gas phase outlet of the gas-liquid separator unit is connected to the inlet of the scrubbing tank unit, and the outlet of the scrubbing tank unit is connected to both the compressor unit and the flare separator. The inlet of the exhaust gas collection unit is connected to both the gas phase outlet of the gas-liquid separator unit and the inlet of the compressor unit, and the outlet of the exhaust gas collection unit is connected to the inlet of the scrubbing tank unit. The control valve of the exhaust gas collection unit is connected to the controller.

[0052] This invention integrates the exhaust gas from each pressure control point during the production process into the gas phase outlet of the low-pressure separator, and pressurizes it together with the associated gas from the low-pressure separator for further processing in the next step. The continuous operation of the low-pressure compressor and the low-pressure suction pressurization configuration solve the problems of unstable exhaust gas and low pressure. The continuous operation solves the problem of intermittent exhaust gas discharge, and the large volume of production gas is compatible with the small volume of exhaust gas. This achieves stable recovery and utilization of exhaust gas, significantly reduces the number of pressure regulating valves and pressure relief valves discharged to the flare, and the amount of flare gas discharged, thereby increasing the economic benefits of the oilfield.

[0053] See Figure 1 As shown, a system for recovering and utilizing exhaust gas from oil and gas field production processes includes a gas-liquid separator unit, an exhaust gas collection unit, a compressor unit, a scrubbing tank unit, a flare distribution tank 12, a controller, and a pressure stabilization unit. The pressure stabilization unit includes a first pressure transmitter 9-1, a frequency converter 10, and a scrubbing tank pressure regulating valve 11. The scrubbing tank pressure regulating valve 11 is provided between the outlet of the scrubbing tank unit and the flare distribution tank 12. The first pressure transmitter 9-1 is used to measure the pressure inside the scrubbing tank unit. The first pressure transmitter 9-1, the frequency converter 10, and the scrubbing tank pressure regulating valve 11 are respectively connected to the controller. The frequency converter 10 is connected to the compressor unit.

[0054] In addition, a gas-associated gas cooler 7 is provided at the inlet of the gas scrubbing tank unit. The inlet of the gas-associated gas cooler 7 is connected to the gas phase outlet of the exhaust gas merging unit and the gas-liquid separator unit, respectively. A second pressure transmitter 9-2 is provided on the production separator 1, and the second pressure transmitter 9-2 is connected to the controller.

[0055] The gas-liquid separator unit is used for gas-liquid separation of crude oil. The unit includes a production separator 1 and a low-pressure separator 2. The production separator 1 is equipped with a first level transmitter 14-1, and the low-pressure separator 2 is equipped with a second level transmitter 14-2. The liquid phase outlet of the production separator 1 is connected to the liquid phase inlet of the low-pressure separator 2, and a fourth regulating valve 4-4 is installed at the liquid phase inlet of the low-pressure separator 2. The first level transmitter 14-1, the second level transmitter 14-2, and the fourth regulating valve 4-4 are respectively connected to a controller. The controller controls the opening and closing of the fourth regulating valve 4-4 based on the liquid level height detected by the first level transmitter 14-1 within the production separator 1. The gas phase outlet of the low-pressure separator 2 is connected to the associated gas cooler 7. The gas phase outlet of the production separator 1 is connected to the inlet of both the exhaust gas merging unit and the scrubbing tank unit. The liquid phase outlet of the low-pressure separator 2 is pumped by the transfer pump 15 to the downstream processing flow for treatment.

[0056] The compressor unit includes a low-pressure compressor 6-1, a medium-pressure compressor 6-2, and a high-pressure compressor 6-3, which are connected in sequence. The air washing tank unit is provided at the air inlet of the low-pressure compressor 6-1, the air inlet of the medium-pressure compressor 6-2, and the air inlet of the high-pressure compressor 6-3, respectively. The medium-pressure compressor 6-2 is connected to the frequency converter 10.

[0057] The exhaust gas manifold unit includes an exhaust gas pipe assembly, a pressure relief valve assembly, and a regulating valve assembly;

[0058] The exhaust pipe assembly includes a first exhaust pipe 5-1, a second exhaust pipe 5-2, and a third exhaust pipe 5-3;

[0059] The pressure relief valve assembly includes a first pressure relief valve 3-1, a second pressure relief valve 3-2, and a third pressure relief valve 3-3;

[0060] The regulating valve assembly includes a first regulating valve 4-1, a second regulating valve 4-2, and a third regulating valve 4-3;

[0061] The first exhaust pipe 5-1 is connected to the gas phase outlet of the production separator 1. The first exhaust pipe 5-1 is equipped with a first pressure relief valve 3-1 and a first regulating valve 4-1 in parallel.

[0062] The second exhaust pipe 5-2 is connected to the intake end of the medium-pressure compressor 6-2. The second exhaust pipe 5-2 is equipped with a second pressure relief valve 3-2 and a second regulating valve 4-2 in parallel.

[0063] The third exhaust pipe 5-3 is connected to the intake end of the high-pressure compressor 6-3. The third exhaust pipe 5-3 is equipped with a third pressure relief valve 3-3 and a third regulating valve 4-3 in parallel.

[0064] The outlets of the first exhaust pipe 5-1, the second exhaust pipe 5-2, and the third exhaust pipe 5-3 are all connected to the associated gas cooler 7. Alternatively, the outlets of the first exhaust pipe 5-1, the second exhaust pipe 5-2, and the third exhaust pipe 5-3 can be individually connected to the associated gas cooler 7, or they can be connected to a main pipe 13, which is connected to the associated gas cooler 7.

[0065] The first pressure relief valve 3-1, the first regulating valve 4-1, the second pressure relief valve 3-2, the second regulating valve 4-2, the third pressure relief valve 3-3, and the third regulating valve 4-3 are respectively connected to the controller.

[0066] The gas washing tank unit includes a low-pressure compressor inlet gas washing tank 8-1, a medium-pressure compressor inlet gas washing tank 8-2, and a high-pressure compressor inlet gas washing tank 8-3. The low-pressure compressor inlet gas washing tank 8-1, the low-pressure compressor 8-1, the medium-pressure compressor inlet gas washing tank 8-2, the medium-pressure compressor 8-2, the high-pressure compressor inlet gas washing tank 8-3, and the high-pressure compressor 6-3 are connected in sequence. A third pressure detection transmitter 9-3 is provided on the medium-pressure compressor inlet gas washing tank 8-2, and a fourth pressure detection transmitter 9-4 is provided on the high-pressure compressor inlet gas washing tank 8-3. The third pressure detection transmitter 9-3 and the fourth pressure detection transmitter 9-4 are respectively connected to the controller.

[0067] A gas cooler 7 is provided at the inlet of the low-pressure compressor inlet scrubbing tank 8-1;

[0068] The inlet of the medium-pressure compressor inlet gas tank 8-2 is also connected to the gas phase outlet of the production separator 1; the pressure detection transmitter is provided on the low-pressure compressor inlet gas tank 8-1, and the outlet of the low-pressure compressor inlet gas tank 8-1 is also connected to the flare separator 12. A gas tank pressure regulating valve 11 is provided between the outlet of the low-pressure compressor inlet gas tank 8-1 and the flare separator 2.

[0069] Work process:

[0070] During normal production, the oil well logistics undergoes gas-liquid separation in production separator 1. The gas phase enters the medium-pressure compressor inlet scrubbing tank 8-2 through pipeline, and then passes through the medium-pressure compressor 6-2, the high-pressure compressor inlet scrubbing tank 8-3, and the high-pressure compressor 6-3 before entering the associated gas user.

[0071] The liquid phase outlet of the production separator 1 is connected to the low-pressure separator 2, and the liquid phase outlet of the low-pressure separator 2 is sent to the downstream processing flow for processing via the transfer pump 15.

[0072] The gas phase outlet of the production separator 1 is connected to the associated gas cooler 7. The associated gas from the low-pressure separator 2 is cooled by the associated gas cooler 7 and its pressure is stabilized by the low-pressure compressor inlet scrubbing tank 8-1 before entering the low-pressure compressor 6-1. The material at the inlet of the low-pressure compressor 6-1 is in a stable state, and the scrubbing tank pressure regulating valve 11 of the low-pressure compressor inlet scrubbing tank 8-1 is closed, allowing the low-pressure compressor 6-1 to operate stably. The associated gas passes through the low-pressure compressor 6-1, the medium-pressure compressor inlet scrubbing tank 8-2, then the medium-pressure compressor 6-2, the high-pressure compressor inlet scrubbing tank 8-3, and finally the high-pressure compressor 6-3 before reaching the associated gas user.

[0073] The pressure in the production separator 1 is detected by the second pressure transmitter 9-2, and the opening and closing of the first regulating valve 4-1 is controlled. When the pressure is too high, the pressure is released through the first pressure relief valve 3-1 and the first exhaust pipe 5-1.

[0074] The pressure in the inlet gas tank 8-2 of the medium-pressure compressor is detected by the third pressure transmitter 9-3, and the opening and closing of the second regulating valve 4-2 is controlled. When the pressure is too high, the pressure is released through the second pressure relief valve 3-2 and the second exhaust pipe 5-2.

[0075] The pressure in the high-pressure compressor inlet gas tank 8-3 is detected by the fourth pressure transmitter 9-4, and the opening and closing of the third regulating valve 4-3 is controlled. When the pressure is too high, the pressure is released through the third pressure relief valve 3-3 and the third exhaust pipe 5-3.

[0076] To ensure continuous operation of the low-pressure compressor 6-1, the following conditions must be met:

[0077] In the exhaust gas input condition, the exhaust gas merges with the associated gas and enters the associated gas cooler 7. The input of new material causes the pressure in the low-pressure compressor inlet scrubbing tank 8-1 to increase. The first pressure detection transmitter 9-1 transmits the pressure signal to the frequency converter 10. According to the pressure-frequency control algorithm, the frequency of the low-pressure compressor 6-1 is increased, thereby increasing the suction capacity of the low-pressure compressor 6-1 and stably reducing the pressure in the low-pressure compressor inlet scrubbing tank 8-1. If the exhaust gas flow rate is large, the frequency converter cannot stabilize the pressure temporarily, and the pressure in the low-pressure compressor inlet scrubbing tank 8-1 is higher than 250 kPaA, the first pressure detection transmitter 9-1 transmits the pressure signal to the scrubbing tank pressure regulating valve 11. According to the positive PID regulation mode, the opening of the scrubbing tank pressure regulating valve 11 is increased, and the associated gas is released to the flare separator 12. The pressure in the low-pressure compressor inlet scrubbing tank 8-1 quickly drops back to the normal operating pressure.

[0078] The pressure-frequency control algorithm is an existing positive feedback process control technology. When the pressure in the compressor's inlet scrubbing tank increases, the compressor's built-in algorithm calculates the corresponding compressor speed and sends this information to the compressor control system to increase the speed and reduce the inlet scrubbing tank pressure; conversely, the speed decreases. The specific calculation methods vary among compressor manufacturers (such as the Solar Turbine compressor from Ledong Gas Field and the GE compressor from Lingshui Gas Field), and the internal parameters are adjusted according to production conditions. This invention does not modify these methods; manufacturers can be selected based on specific needs.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A system for recycling of gas produced during oil and gas field production, c h a r a c t e r i s e d in that It includes a gas-liquid separator unit, an exhaust gas manifold unit, a compressor unit, a scrubbing tank unit, a flare separator, and a controller; The gas-liquid separator unit is used to separate crude oil into gas and liquid phases. The gas phase outlet of the gas-liquid separator unit is connected to the inlet of the gas scrubbing tank unit, and the outlet of the gas scrubbing tank unit is connected to the compressor unit and the flare separator tank, respectively. The air inlet of the exhaust gas merging unit is connected to the gas phase outlet of the gas-liquid separator unit and the air inlet of the compressor unit, respectively. The air outlet of the exhaust gas merging unit is connected to the air inlet of the scrubbing tank unit. The control valve of the exhaust gas merging unit is connected to the controller. It also includes a pressure stabilization unit, which includes a first pressure transmitter, a frequency converter, and a gas tank pressure regulating valve. The gas tank pressure regulating valve is provided between the gas outlet of the gas tank unit and the flare separator. The first pressure transmitter is used to measure the pressure inside the gas tank unit. The first pressure transmitter, the frequency converter, and the gas tank pressure regulating valve are respectively connected to the controller. The frequency converter is connected to the compressor unit. It also includes an associated gas cooler, which is located at the inlet of the gas scrubbing tank unit, and the inlet of the associated gas cooler is connected to the gas phase outlet of the exhaust gas merging unit and the gas-liquid separator unit respectively. The compressor unit includes a low-pressure compressor, a medium-pressure compressor, and a high-pressure compressor. The low-pressure compressor, the medium-pressure compressor, and the high-pressure compressor are connected in sequence. The air washing tank unit is provided at the air inlet of the low-pressure compressor, the air inlet of the medium-pressure compressor, and the air inlet of the high-pressure compressor. The medium-pressure compressor is connected to the frequency converter. The gas washing tank unit includes a low-pressure compressor inlet gas washing tank, a medium-pressure compressor inlet gas washing tank, and a high-pressure compressor inlet gas washing tank, which are connected in sequence. The associated gas cooler is provided at the inlet of the low-pressure compressor inlet scrubbing tank; The air inlet of the medium-pressure compressor inlet scrubbing tank is also connected to the gas-liquid separator unit; The first pressure detection transmitter is provided on the inlet gas washing tank of the low-pressure compressor. The outlet of the inlet gas washing tank of the low-pressure compressor is also connected to the flare liquid separator. The gas washing tank pressure regulating valve is provided between the outlet of the inlet gas washing tank of the low-pressure compressor and the flare liquid separator. The exhaust gas manifold unit includes an exhaust gas pipe assembly, a pressure relief valve assembly, and a regulating valve assembly; The exhaust pipe assembly includes a first exhaust pipe, a second exhaust pipe, and a third exhaust pipe; The pressure relief valve assembly includes a first pressure relief valve, a second pressure relief valve, and a third pressure relief valve; The regulating valve assembly includes a first regulating valve, a second regulating valve, and a third regulating valve; The first exhaust pipe is connected to the gas phase outlet of the gas-liquid separator unit, and the first pressure relief valve and the first regulating valve are connected in parallel on the first exhaust pipe. The second discharge pipe is connected to the inlet end of the medium-pressure compressor, and the second pressure relief valve and the second regulating valve are connected in parallel on the second discharge pipe; The third exhaust pipe is connected to the intake end of the high-pressure compressor, and the third pressure relief valve and the third regulating valve are connected in parallel on the third exhaust pipe; The outlet ends of the first exhaust pipe, the second exhaust pipe, and the third exhaust pipe are all connected to the associated gas cooler. The first pressure relief valve, the first regulating valve, the second pressure relief valve, the second regulating valve, the third pressure relief valve, and the third regulating valve are respectively connected to the controller; The gas-liquid separator unit includes a production separator and a low-pressure separator. The liquid phase outlet of the production separator is connected to the liquid phase inlet of the low-pressure separator. The gas phase outlet of the production separator is connected to the first exhaust gas pipe and the inlet of the medium-pressure compressor inlet scrubbing tank, respectively. The gas phase outlet of the low-pressure separator is connected to the associated gas cooler.

2. The oil and gas field production process off-gas recycling system of claim 1, wherein, The gas-liquid separator unit is equipped with a second pressure transmitter, which is connected to the controller.

3. The oil and gas field production process off-gas recycling system of claim 1, wherein, A third pressure transmitter is installed on the inlet gas washing tank of the medium-pressure compressor, and the third pressure transmitter is connected to the controller.

4. The oil and gas field production process off-gas recycling system of claim 1, wherein, The high-pressure compressor inlet gas tank is equipped with a fourth pressure transmitter, which is connected to the controller.

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