Independent island type full-quantification recovery method for oilfield associated gas

Abstract

The invention discloses an independent island type full-quantification recovery method for oilfield associated gas. The independent island type full-quantification recovery method comprises the following steps: gas feeding; the gas entering the compression conveying unit is firstly filtered and separated and then enters a gas compressor to be compressed and pressurized at the normal temperature, the pressurized gas is subjected to gas and oil separation, and the separated gas is conveyed to an air cooling heat exchanger to be cooled to the normal temperature to be output to a pressurization condensation unit; pressurizing and condensing: the pressurized normal-temperature gas with pressure enters a pressurizing and condensing unit, is subjected to first-stage cooling, second-stage cooling and third-stage cooling in sequence, and then enters an oil-gas separator; and dry gas power generation. By combining pressurized condensation recovery and compression conveying, on one hand, oil gas can be transmitted remotely, on the other hand, the recovery efficiency of the oilfield associated gas is greatly improved, on the third hand, by means of the self-contained oilfield associated gas power generation function, single-island type full-quantitative recovery is achieved, and the device is environmentally friendly, energy-saving and efficient.

Description

Technical Field

[0001] The invention belongs to the technical field of oil field oil and gas recovery, and in particular relates to a single-island type full-quantity recovery method for oil field associated gas. Background Art

[0002] Oilfield associated gas refers to the natural gas extracted simultaneously with oil during the oil extraction process. Its main component is methane, and it contains small amounts of light hydrocarbons, heavy hydrocarbons, hydrogen sulfide and other components.

[0003] Traditionally, oilfield associated gas is mostly treated by combustion. This traditional treatment mode has many disadvantages, which is a huge waste of resource utilization and has a high energy consumption. From the perspective of environmental impact, the combustion of associated gas is likely to cause environmental pollution problems, such as the emission of large amounts of greenhouse gases and other pollutants into the atmosphere, which damages the ecological balance.

[0004] With the progress of society and the development of science and technology, how to adopt effective recovery and utilization production processes to efficiently separate oil field associated gas into dry gas and condensate oil, and then convert it into high value-added products such as liquefied natural gas, liquefied petroleum gas, and power generation, on the one hand, significantly improve resource utilization and create considerable economic benefits, on the other hand, it also greatly reduces carbon emissions and promotes green and low-carbon development. Thirdly, the effective use of associated gas reduces dependence on other energy sources and promotes the sustainable use of resources. This is of great significance to protecting the global ecological environment and achieving long-term sustainable development. The above problems need to be solved urgently.

[0005] Therefore, in recent years, with the increasing emphasis on resources and environmental protection requirements, the recovery and utilization of oilfield associated gas has become an important research direction. Summary of the invention

[0006] Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a single-island type fully quantitative recovery method for oil field associated gas.

[0007] Technical solution: The present invention provides a one-island type full-quantity recovery method for oilfield associated gas, which is used for a one-island type full-quantity recovery system for oilfield associated gas, the system includes an air intake unit, a compression and transportation unit, a pressurized condensation separation unit, an emergency air discharge unit and a dry gas power generation unit; the method includes the following steps:

[0008] The air intake step specifically includes: in the air intake unit, the oilfield associated gas drawn in enters the compression and delivery unit through the air intake flow meter and the air intake flame arrester;

[0009] The step of compression and transportation specifically includes: the gas entering the compression and transportation unit through the air intake unit is first filtered and separated by the air intake filter, and then enters the dynamic equipment gas compressor for compression and pressurization at room temperature, the pressurized gas enters the oil-gas separator for separation of gas and oil, and the separated gas is sent to the air-cooled heat exchanger for air-cooled heat exchange and cooled to room temperature, and then output to the pressurized condensing unit;

[0010] The step of pressurized condensation specifically includes: the pressurized normal temperature gas after being pressurized by the compression and delivery unit enters the pressurized condensation unit, and first enters the air-cooled recovery heat exchanger for gas-to-gas heat exchange and primary cooling;

[0011] When a branch is ventilated, the gas after primary cooling can enter the dehydration heat exchanger of the branch for secondary cooling to separate free water or some heavy hydrocarbons, and then enter the pressurized condensation oil separation heat exchanger of the branch for tertiary cooling to separate supersaturated water or some light hydrocarbons, and then enter the oil-gas separator through the outlet cut-off valve of the branch;

[0012] The step of dry gas power generation specifically includes: the associated dry gas input into the dry gas power generation unit is sequentially input into the associated gas generator through the first intermediate one-way valve and the inlet one-way valve to generate electricity.

[0013] Further preferably, the method further comprises: a step of emergency exhaust; specifically comprising: when the oxygen content measured by the oxygen content detector in the air intake unit is higher than a first preset oxygen content threshold, opening the air intake emergency exhaust valve in the emergency exhaust unit to perform emergency exhaust; when the oxygen content measured by the oxygen content detector is lower than the first preset oxygen content threshold, closing the air intake emergency exhaust valve;

[0014] When the pressure value measured by the intake pressure transmitter exceeds the first preset pressure threshold, the intake emergency exhaust valve is opened / activated to perform emergency exhaust; when the pressure value measured by the intake pressure transmitter is less than the first preset pressure threshold, the intake emergency exhaust valve is closed;

[0015] When the flow rate measured by the air intake flow meter exceeds the rated flow rate of the whole equipment, open / activate the air intake emergency exhaust valve for emergency exhaust; when the flow rate measured by the air intake flow meter is lower than the rated flow rate of the whole equipment, close the air intake emergency exhaust valve;

[0016] When the pressure of the oil safety valve in the emergency air discharge unit exceeds its set pressure, open the oil safety valve to discharge air urgently.

[0017] Further preferably, the method further comprises:

[0018] The step of collecting and recovering liquids; specifically comprising: the water or part of hydrocarbon liquid condensed and separated from the oilfield associated gas in the water removal heat exchanger A, the pressurized condensation oil separation heat exchanger A, the water removal heat exchanger B, the pressurized condensation oil separation heat exchanger B, and the oil-gas separator respectively flows into the condensate tank for collecting and recovering liquids; and / or

[0019] The air cooling start and stop steps include: when the temperature measured by the air cooling temperature transmitter is higher than the first preset air cooling threshold, the air cooling fan is turned on; when the temperature measured by the air cooling temperature transmitter is lower than the second preset air cooling threshold, the air cooling fan is turned off; and / or

[0020] The steps of starting and stopping oil cooling include: when the temperature measured by the oil temperature transmitter is higher than the first preset oil cooling threshold, the oil cooling fan is turned on; when the temperature measured by the oil temperature transmitter is lower than the second preset oil cooling threshold, the oil cooling fan is turned off.

[0021] Further preferably, the method further comprises: a chain alarm step; specifically comprising:

[0022] When the pressure measured by the outlet gas pressure transmitter is higher than a third preset pressure threshold, an alarm is triggered and the gas compressor is shut down; and / or

[0023] When the liquid level measured by the liquid level transmitter is lower than a first preset liquid level threshold, an interlock alarm is triggered and the gas compressor (203) is shut down; and / or

[0024] When the oxygen content measured by the oxygen content detector is higher than a first preset oxygen content threshold, the air intake emergency exhaust valve is opened to perform emergency exhaust, and an interlocking alarm is triggered and the gas compressor is shut down; and / or

[0025] When the pressure value measured by the intake pressure transmitter exceeds a first preset pressure threshold, the intake emergency exhaust valve is opened / activated to perform emergency exhaust, and an alarm is simultaneously interlocked and the gas compressor is shut down; and / or

[0026] When the flow rate measured by the air intake flow meter exceeds the rated flow rate of the whole equipment, the air intake emergency exhaust valve is opened / activated to discharge air urgently, and at the same time, an alarm is triggered and the gas compressor is shut down.

[0027] Preferably, in the step of pressurized condensation:

[0028] The associated dry gas output from the oil-gas separator enters the air-cooled recovery heat exchanger for cold recovery, and then passes through the first intermediate check valve and the inlet check valve in sequence to enter the associated gas generator for power generation;

[0029] Among them, the cold source of the water removal heat exchanger A is provided by the first refrigeration compressor; the cold source of the pressurized condensing oil separation heat exchanger A is provided by the second refrigeration compressor; the cold source of the water removal heat exchanger B is provided by the third refrigeration compressor); the cold source of the pressurized condensing oil separation heat exchanger B is provided by the fourth refrigeration compressor;

[0030] Among them, the power supply required by the first refrigeration compressor, the second refrigeration compressor, the third refrigeration compressor, the fourth refrigeration compressor, the gas compressor, the air-cooling fan, the oil-cooling fan and other moving parts, and the control power supply required by each valve and each instrument are all provided by the associated gas generator, realizing the island operation of the entire device / system.

[0031] Further preferably, when the oilfield associated gas is first introduced, it first passes through the air intake flow meter, the air intake flame arrester, the air outlet emergency exhaust valve, the second intermediate one-way valve, and the inlet one-way valve, and enters the associated gas generator to generate electricity, providing power supply for the entire system;

[0032] Among them, when the associated gas generator obtains gas to generate electricity, the refrigeration compressor of the A-side branch or the B-side branch can be started to establish the cold field temperature of the water removal heat exchanger and the pressurized condensation oil separation heat exchanger of the corresponding branch. After the cold field temperature is established, the outlet emergency exhaust valve is closed, the gas compressor is started, and the air inlet shut-off valve and the air outlet shut-off valve of the corresponding branch are opened. The system operation process of oilfield associated gas intake, compression and transportation, pressurization and condensation and dry gas power generation.

[0033] Preferably, the first preset oxygen content threshold is adjustable and is set to 5%.

[0034] Preferably, the first preset pressure threshold is adjustable and is set to 2500Pa.

[0035] As a preferred option, the rated flow rate of the whole equipment is adjustable and is set to 3000m 3 / d.

[0036] Preferably, the set pressure of the oil safety valve (404) is set to 0.96 MPa.

[0037] Preferably, the third preset pressure threshold is adjustable and is set to 0.88 MPa.

[0038] Preferably, the first preset liquid level threshold is adjustable and is set to 50 mm.

[0039] Preferably, the first preset air cooling threshold is adjustable and is set to 40°C.

[0040] Preferably, the second preset air cooling threshold is adjustable and is set to 25°C.

[0041] Preferably, the first preset oil cooling threshold is adjustable and is set to 60°C.

[0042] Preferably, the second preset oil cooling threshold is adjustable and is set to 50°C.

[0043] Further preferably, the A side branch and the B side branch are switched regularly according to a set time period;

[0044] When the A-side branch is ventilated, the air inlet cut-off valve A and the air outlet cut-off valve A are opened; when the A-side branch is not ventilated, the air inlet cut-off valve A and the air outlet cut-off valve A are closed;

[0045] When the B-side branch is ventilated, the air inlet cut-off valve B and the air outlet cut-off valve B are opened; when the B-side branch is not ventilated, the air inlet cut-off valve B and the air outlet cut-off valve B are closed;

[0046] Among them, the air inlet cut-off valve A and the air outlet cut-off valve A on the A-side branch are opened and closed at the same time;

[0047] Among them, the air intake cut-off valve B and the air outlet cut-off valve B on the B side branch are opened and closed at the same time.

[0048] Further preferably, after the associated gas generator obtains gas for the first time to generate electricity, and when the A side branch is selected for ventilation, the first refrigeration compressor and the second refrigeration compressor on the A side branch are started to establish the cold field temperature of the water removal heat exchanger A and the pressurized condensation oil separation heat exchanger A; after the first cold field temperature is established, the outlet emergency exhaust valve is closed, the gas compressor is started, and the air intake shut-off valve A and the air outlet shut-off valve A are opened, and the oilfield associated gas is subjected to the conventional system operation process of air intake, compression and transportation, pressurization and condensation, and dry gas power generation;

[0049] When the associated gas generator obtains gas for the first time to generate electricity and the B side branch is selected for ventilation, the third refrigeration compressor and the fourth refrigeration compressor on the B side branch are started to establish the cold field temperature of the water removal heat exchanger B and the pressurized condensation oil separation heat exchanger B; after the first cold field temperature is established, the air outlet emergency exhaust valve is closed, the gas compressor is started, and the air inlet shut-off valve B and the air outlet shut-off valve B are opened, and the oilfield associated gas is subjected to the conventional system operation process of air intake, compression and transportation, pressurization and condensation, and dry gas power generation.

[0050] Further preferably, when the associated gas generator is continuously generating gas, such as switching between the A-side branch and the B-side branch, before switching, the refrigeration compressor of the other branch is first started to establish the cold field temperature of the dehydration heat exchanger and the pressurized condensation oil separation heat exchanger of the corresponding branch. After the cold field temperature is established, the air inlet shut-off valve and the air outlet shut-off valve of the original ventilation branch are closed, and the air inlet shut-off valve and the air outlet shut-off valve of the branch to be ventilated are opened / opened, so as to realize seamless and flexible switching of the bilateral branches, and realize the continuous operation of the oilfield associated gas for air intake, compression and transportation, pressurization condensation and dry gas power generation; the original ventilation branch that is switched is switched from the refrigeration mode to the defrost mode, and the branch is shut down after the defrost is completed, until the refrigeration compressor of the branch is started again to enter the refrigeration mode before the next branch switching, and the cold field temperature of the dehydration heat exchanger and the pressurized condensation oil separation heat exchanger of the branch is established; and the cycle operation is alternating in this way.

[0051] Further preferably, specifically, when the associated gas generator is continuously generating gas, such as switching from the A side branch to the B side branch, before switching, the third refrigeration compressor and the fourth refrigeration compressor on the B side branch are started first to establish the cold field temperature of the dehydration heat exchanger B and the pressurized condensation oil separation heat exchanger B. After the cold field temperature is established, the air inlet shut-off valve B and the air outlet shut-off valve B of the B side branch are opened / opened, and the air inlet shut-off valve A and the air outlet shut-off valve A of the A side branch are closed to achieve seamless switching from the A side branch to the B side branch, thereby achieving continuous operation of oilfield associated gas intake, compression and transportation, pressurization condensation and dry gas power generation; the switched A side branch is switched from the refrigeration mode to the defrost mode, and the first refrigeration compressor and the second refrigeration compressor of the A side branch are shut down after the defrost is completed, until the first refrigeration compressor and the second refrigeration compressor of the A side branch are started again before the next branch switching to enter the refrigeration mode, and the cold field temperature of the A side branch dehydration heat exchanger A and the pressurized condensation oil separation heat exchanger A is established; and the alternating cycle operation is carried out in this way.

[0052] Further preferably, specifically, when the associated gas generator is continuously generating gas, such as switching from the B side branch to the A side branch, before switching, the first refrigeration compressor and the second refrigeration compressor on the A side branch are started first to establish the cold field temperature of the dehydration heat exchanger A and the pressurized condensation oil separation heat exchanger A. After the cold field temperature is established, the air inlet shut-off valve A and the air outlet shut-off valve A of the A side branch are opened / opened, and the air inlet shut-off valve B and the air outlet shut-off valve B of the B side branch are closed to achieve seamless switching from the B side branch to the A side branch, thereby achieving continuous operation of oilfield associated gas intake, compression and transportation, pressurization condensation and dry gas power generation; the switched B side branch is switched from the refrigeration mode to the defrost mode, and the third refrigeration compressor and the fourth refrigeration compressor of the B side branch are shut down after the defrost is completed, until the third refrigeration compressor and the fourth refrigeration compressor of the B side branch are started again before the next branch switching to enter the refrigeration mode, and the cold field temperature of the dehydration heat exchanger B and the pressurized condensation oil separation heat exchanger B of the B side branch is established; and the alternating cycle operation is carried out in this way.

[0053] The present invention also provides another one-island type full-quantity recovery method for oilfield associated gas, which is used for the one-island type full-quantity recovery system of oilfield associated gas, the system includes an air intake unit, a compression and transportation unit, a pressurized condensation separation unit, an emergency air discharge unit and a dry gas power generation unit; the method includes the following steps:

[0054] The air intake step specifically includes: in the air intake unit, the oilfield associated gas drawn in enters the compression and delivery unit through the air intake flow meter and the air intake flame arrester;

[0055] The step of compression and transportation specifically includes: the gas entering the compression and transportation unit through the air intake unit first passes through the air intake filter for high-efficiency filtration and separation, then enters the dynamic equipment gas compressor through the loading valve for room temperature compression and pressurization to a first compression and pressurization threshold, the pressurized gas enters the oil-gas separator for gas and oil separation, the separated gas is discharged from the first gas outlet end of the oil-gas separator, and is transported to the air-cooled heat exchanger through the oil-gas one-way valve for air-cooled heat exchange and cooled to room temperature, and then output to the pressurized condensing unit;

[0056] The step of pressurized condensation specifically includes: the pressurized normal temperature gas after being pressurized by the compression and delivery unit enters the pressurized condensation unit, and first enters the air-cooled recovery heat exchanger for gas-to-gas heat exchange and primary cooling;

[0057] When the A-side branch is ventilated, the gas after primary cooling can enter the water removal heat exchanger A through the air inlet cut-off valve A for secondary cooling to separate free water or some heavy hydrocarbons, and then enter the pressurized condensation oil separation heat exchanger A for tertiary cooling to separate supersaturated water or some light hydrocarbons, and then enter the oil-gas separator through the air outlet cut-off valve A;

[0058] When the B-side branch is ventilated, the gas after the primary cooling can enter the water removal heat exchanger B through the air inlet cut-off valve B for the secondary cooling to separate free water or some heavy hydrocarbons, and then enter the pressurized condensation oil separation heat exchanger B for the tertiary cooling to separate supersaturated water or some light hydrocarbons, and then enter the oil-gas separator through the air outlet cut-off valve B;

[0059] The step of emergency exhausting air; specifically comprising: when the oxygen content measured by the oxygen content detector in the air intake unit is higher than the first preset oxygen content threshold, opening the air intake emergency exhaust valve in the emergency exhaust unit to emergency exhaust air; when the oxygen content measured by the oxygen content detector is lower than the first preset oxygen content threshold, closing the air intake emergency exhaust valve;

[0060] When the pressure value measured by the intake pressure transmitter exceeds the first preset pressure threshold, the intake emergency exhaust valve is opened / activated to perform emergency exhaust; when the pressure value measured by the intake pressure transmitter is less than the first preset pressure threshold, the intake emergency exhaust valve is closed;

[0061] When the flow rate measured by the air intake flow meter exceeds the rated flow rate of the whole equipment, open / activate the air intake emergency exhaust valve for emergency exhaust; when the flow rate measured by the air intake flow meter is lower than the rated flow rate of the whole equipment, close the air intake emergency exhaust valve;

[0062] When the pressure of the oil safety valve in the emergency air discharge unit exceeds its set pressure, open the oil safety valve to discharge air urgently;

[0063] The steps of dry gas power generation specifically include: the associated gas dry gas output from the oil-gas separator enters the air-cooled recovery heat exchanger for cold recovery, and then is input into the dry gas power generation unit and sequentially passes through the first intermediate one-way valve and the inlet one-way valve to enter / enter the associated gas generator for power generation.

[0064] Further preferably, when the oilfield associated gas is first introduced, the oilfield associated gas is successively / sequentially passed through the intake flow meter, the intake flame arrester, the exhaust valve, the second intermediate check valve, and the inlet check valve, and is input / entered into the associated gas generator to generate electricity.

[0065] Further preferably, part of the associated dry gas can be output to external equipment via a self-operated regulating valve, an outlet one-way valve and an outlet flame arrester in sequence.

[0066] Preferably, in the step of compression and transportation, the temperature of the gas after pressurization by the gas compressor is between 60 and 80°C, and then it is cooled to a normal temperature of about 45°C by an air-cooled heat exchanger.

[0067] Preferably, the first compression pressure threshold is set to 0.8 MPa.

[0068] Preferably, the oil and gas one-way valve is a mechanical one, and its pressure setting value is 0.4 MPa.

[0069] Preferably, the pre-valve pressure threshold of the self-operated regulating valve is adjustable and is set to 0.7 MPa.

[0070] Preferably, the pre-valve pressure threshold of the automatic regulating valve is adjustable and is set to 0.7 MPa.

[0071] Preferably, the cold field temperature of the dewatering heat exchanger A is +5°C.

[0072] Preferably, the cold field temperature of the pressurized condensing oil separation heat exchanger A is -35°C.

[0073] Preferably, the cold field temperature of the water removal heat exchanger B is +5°C.

[0074] Preferably, the cold field temperature of the pressurized condensing oil separation heat exchanger B is -35°C.

[0075] Preferably, the cold field temperature of the air-cooled recovery heat exchanger is 15°C.

[0076] Preferably, the emergency exhaust valve is a normally open valve.

[0077] Further preferably, any of the above-mentioned one-island-type fully quantitative recovery methods for oilfield associated gas is used for a one-island-type fully quantitative recovery system for oilfield associated gas, the system comprising an air intake unit, a compression and conveying unit connected to the gas phase pipeline of the air intake unit, a pressurized condensing unit connected to the gas phase pipeline of the compression and conveying unit, a dry gas power generation unit connected to the gas phase pipeline of the pressurized condensing unit, and an emergency air discharge unit connected to the gas phase pipelines of the air intake unit, the compression and conveying unit, and the dry gas power generation unit;

[0078] The air intake unit includes an air intake flow meter and an air intake flame arrester connected to the air outlet end of the air intake flow meter;

[0079] The gas phase pipeline of the compression and delivery unit includes an air intake filter, a loading valve connected to the outlet end of the air intake filter, a gas compressor connected to the outlet end of the loading valve, an oil-gas separator connected to the outlet end of the gas compressor, an oil-gas one-way valve connected to the first air outlet end of the oil-gas separator, a reflux cut-off valve connected to the second air outlet end of the oil-gas separator, and an air-cooled heat exchanger connected to the outlet end of the oil-gas one-way valve;

[0080] The oil phase pipeline of the compression and delivery unit includes an oil-gas separator, an oil-cooling heat exchanger connected to the oil outlet end of the oil-gas separator, an oil filter connected to the outlet end of the oil-cooling heat exchanger, and an oil cut-off valve connected to the outlet end of the oil filter; the other end of the oil cut-off valve is connected to the oil return port of the gas compressor.

[0081] Further preferably, the pressurized condensing unit includes an air-cooled recovery heat exchanger, and an air intake cut-off valve A, a water removal heat exchanger A, a pressurized condensing oil separation heat exchanger A and an air outlet cut-off valve A located on the A side branch, and an air intake cut-off valve B, a water removal heat exchanger B, a pressurized condensing oil separation heat exchanger B, and an air outlet cut-off valve B located on the B side branch;

[0082] The emergency exhaust unit includes an air inlet emergency exhaust valve, an oil separation safety valve and an air outlet emergency exhaust valve;

[0083] The dry gas power generation unit comprises a first intermediate one-way valve, a second intermediate one-way valve, an associated gas generator and a self-operated regulating valve.

[0084] Further preferably, the inlet end of the air intake emergency exhaust valve is connected to the outlet of the air intake flame arrester (102) in the air intake unit;

[0085] The inlet end of the oil safety valve is connected to the third outlet end of the oil-gas separator;

[0086] The inlet end of the air outlet emergency exhaust valve is connected to the outlet of the air intake flame arrester in the air intake unit;

[0087] The inlet end of the second intermediate one-way valve is connected to the outlet end of the emergency exhaust valve;

[0088] The inlet end of the first intermediate one-way valve is connected to the cold side air path outlet of the air-cooled recovery heat exchanger.

[0089] More preferably, the reflux cut-off valve is interlockedly controlled with the gas compressor.

[0090] More preferably, the air-cooled temperature transmitter is interlockedly controlled with the air-cooled fan.

[0091] More preferably, the oil temperature transmitter is interlocked with the oil cooling fan.

[0092] More preferably, the outlet pressure transmitter and the liquid level transmitter are both interlocked with the gas compressor.

[0093] More preferably, the oxygen content detector, the intake pressure transmitter and the intake flow meter are all interlocked with the gas compressor.

[0094] More preferably, the oxygen content detector, the intake pressure transmitter and the intake flow meter are all interlocked with the intake emergency exhaust valve.

[0095] Beneficial effects: The island-type fully quantitative recovery method and system for oilfield associated gas provided by the present invention combines compression transportation and pressurized condensation, and has the following advantages over the prior art:

[0096] (1) The Dokdo-type fully quantitative recovery method and system for oilfield associated gas provided by the present invention integrates the technologies of gas compression and pressurized condensation through a combined process of pressurization and condensation. A high recovery rate can be achieved by pressurized condensation to about -35°C, without the need for ultra-low temperature condensation at about -70°C, thereby greatly improving resource utilization efficiency.

[0097] (2) In the single-island type fully quantitative recovery method and system for oilfield associated gas provided by the present invention, multiple dimensions of emergency discharge air are set up to effectively avoid overpressure, overflow, and overoxygen content, and have high safety.

[0098] (3) The island-type fully quantitative recovery method and system for oilfield associated gas provided by the present invention is a compression pressure conveying system. Through compression pressure conveying, long-distance conveying can be achieved, and the conveying distance can be as long as several thousand meters. Moreover, pressure conveying at normal temperature is safe and reliable.

[0099] (4) The single-island type full-quantity recovery method and system for oilfield associated gas provided by the present invention is equipped with four independent refrigeration systems with two-way two-stage condensation to provide the required cooling capacity for the associated gas. The automatic switching of the A / B bilateral branches can effectively ensure the continuity of the associated gas recovery operation. Even under load changes or high-intensity use, the system can maintain stability and efficiency, ensuring continuous operation 24 hours a day.

[0100] (5) At the same time, in the single-island type fully quantitative recovery method and system for oilfield associated gas provided by the present invention, the dual parallel design of the A / B bilateral branches and the segmented multi-stage high-efficiency condensation recovery technology can optimize the recovery process according to the exhaust gas temperature, combined with different cold field temperature setting controls, etc., and can significantly reduce the heat load of the subsequent compressor, thereby ensuring the long-term stable operation of the entire process / system / device.

[0101] (6) In the single-island type full-quantity recovery method and system for oilfield associated gas provided by the present invention, the pressurized condensing unit adopts a dual-branch channel. When one branch / channel is working, the other branch / channel can automatically enter the defrosting process to eliminate ice blockage. In this way, the dual branches / channels are switched periodically and uninterruptedly, which can effectively ensure that the air intake unit continuously intakes air and the entire process / system / equipment can meet 24-hour continuous operation.

[0102] (7) In the single-island type full-quantity recovery method and system for oilfield associated gas provided by the present invention, the pressurized condensing unit first performs gas-to-gas heat exchange and first-stage cooling. The gas after the first-stage cooling can enter the dewatering heat exchanger of the corresponding branch for second-stage cooling to separate free water or part of heavy hydrocarbons, and then enter the pressurized condensing oil separation heat exchanger of the branch for third-stage cooling to separate supersaturated water or part of light hydrocarbons. Through this unique light hydrocarbon component separation technology, most of the volatile light components are stripped from the recovered condensate oil, significantly reducing its volatility. This technology makes the recovered oil products more stable and safe during transportation and storage, and at the same time makes the recovered condensate oil more stable and reliable in chemical processing and industrial use, improves the use value of the oil products, and promotes the effective use of resources.

[0103] (8) Based on the structure and construction provided by the present invention, the power supply required by the four refrigeration compressors, gas compressors, air cooling fans, oil cooling fans and other moving parts in the dual-path two-stage condensation four-set independent refrigeration system, as well as the control power supply required by each valve and each instrument, can be provided by the associated gas generator, thereby realizing the island operation of the entire device / system; the entire device / system not only has the ability to efficiently recover condensate oil, but also can be self-sufficient to achieve island-type power generation, power supply and gas recovery without the need for external power supply. On the one hand, it can ensure normal operation in an environment without public engineering support, and the power generation technology meets the requirements of severe working conditions. On the other hand, through the built-in oil field associated gas power generation function, it can not only maintain the continuous operation of the system / equipment itself, but also supply surplus electricity to the operation of other surrounding power facilities; overall, the full energy recovery of oil field associated gas is realized (wherein the full energy recovery can be referred to as full quantification, which means that in the oil field associated gas recovery process of the present invention, on the one hand, liquid condensate oil, etc. are recovered, and on the other hand, gas is used for power generation, and all are converted into energy to the maximum extent), which is green, environmentally friendly, energy-saving and efficient.

[0104] (9) Based on the structure and construction provided by the present invention, the associated gas of the oil field can be filtered and separated by an air intake filter first, and then enter the gas compressor for compression and pressurization at room temperature. The pressurized gas is separated into gas and oil, and the separated gas is transmitted to an air-cooled heat exchanger for air-cooled heat exchange and cooled to room temperature. The pressurized room-temperature gas is then pressurized and condensed in three stages. The technology of gas compression and pressurized condensation is effectively integrated. Efficient recovery can be achieved by pressurizing and condensing to about -35°C (no ultra-low temperature condensation of about -70°C is required, which greatly improves the resource utilization efficiency), which is green and environmentally friendly.

[0105] In general, the present invention can effectively overcome the resistance in the fluid transportation process by combining pressurized condensation recovery and compression transportation, so that oil and gas can be transmitted more quickly and over longer distances, and the recovery efficiency of oilfield associated gas can be greatly improved; the present invention can use its own oilfield associated gas power generation function to not only power the system internally to maintain the continuous operation of the system / equipment itself, but also maintain efficient and stable operation under different load and environmental conditions, and the surplus electricity can also be supplied to the operation of other surrounding power facilities, realizing single-island full-quantity recovery. Overall, it is green, environmentally friendly, energy-saving and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0106] Figure 1 This is a schematic structural diagram of one of the Dokdo-type full-quantity recovery systems used in one of the Dokdo-type full-quantity recovery methods for oilfield associated gas provided in this embodiment.

[0107] In the figure, 100-air intake unit, 200-compression and transportation unit, 300-pressurization and condensation unit, 400-urgent air discharge unit, 500-dry gas power generation unit;

[0108] 101-intake flow meter, 102-intake flame arrester, 103-oxygen content detector, 106-intake pressure transmitter;

[0109] 201-intake filter, 202-loading valve, 203-gas compressor, 204-oil-gas separator, 205-oil-gas check valve, 2061-air-cooling fan, 2062-air-cooling heat exchanger, 207-temperature transmitter, 208-outlet pressure transmitter, 2091-oil-cooling fan, 2092-oil-cooling heat exchanger, 210-liquid level transmitter, 211-oil filter, 212-oil cut-off valve, 213-oil temperature transmitter, 214-return cut-off valve;

[0110] 301-air-cooled recovery heat exchanger, 3021-water removal heat exchanger A, 3022-water removal heat exchanger B, 3031-pressurized condensing oil separation heat exchanger A, 3032-pressurized condensing oil separation heat exchanger B, 304-oil-gas separator, 305-condensate tank, 3061-air inlet shut-off valve A, 3062-air inlet shut-off valve B, 3071-air outlet shut-off valve A, 3072-air outlet shut-off valve B, 3111-first refrigeration compressor, 3121-second refrigeration compressor, 3112-third refrigeration compressor, 3122-fourth refrigeration compressor;

[0111] 401-air intake emergency exhaust valve, 402-fire arrester single call valve, 403-air outlet emergency exhaust valve, 404-oil separation safety valve;

[0112] 501-associated gas generator, 502-inlet one-way valve, 503-first intermediate one-way valve, 504-second intermediate one-way valve, 505-gas outlet regulating valve, 506-gas outlet flame arrester, 507-self-operated regulating valve, 508-export one-way valve. DETAILED DESCRIPTION

[0113] The present invention will be further described in detail below in conjunction with the embodiments and drawings, and the following embodiments do not limit the present invention.

[0114] This embodiment provides a single-island type full-quantity recovery method for oilfield associated gas, which comprises the following steps:

[0115] The air intake step specifically includes: in the air intake unit 100, the oilfield associated gas drawn in enters the compression and delivery unit 200 through the air intake flow meter 101 and the air intake flame arrester 102;

[0116] The step of compression and delivery specifically includes: the gas entering the compression and delivery unit 200 through the air intake unit 100 is first filtered and separated by the air intake filter 201, and then enters the power equipment gas compressor 203 for compression and pressurization at room temperature, and the pressurized gas enters the oil-gas separator 204 for separation of gas and oil, and the separated gas is sent to the air-cooled heat exchanger 2062 for air-cooled heat exchange and cooled to room temperature, and then output to the pressurized condensing unit 300;

[0117] The step of pressurized condensation specifically includes: the pressurized normal temperature gas after being pressurized by the compression and delivery unit 200 enters the pressurized condensation unit 300, and first enters the air-cooled recovery heat exchanger 301 for air-to-air heat exchange and first-stage cooling (in this embodiment, air-to-air heat exchange and first-stage cooling are performed, and the temperature drops to about 15°C. Among them, the cold field temperature of the air-cooled recovery heat exchanger 301 is 15°C);

[0118] When a branch is ventilated, the gas after primary cooling can enter the dehydration heat exchanger of the branch for secondary cooling to separate free water or part of heavy hydrocarbons, and then enter the pressurized condensation oil separation heat exchanger of the branch for tertiary cooling to separate supersaturated water or part of light hydrocarbons, and then enter the oil-gas separator 304 through the outlet cut-off valve of the branch;

[0119] The step of dry gas power generation specifically includes: the associated gas dry gas input into the dry gas power generation unit 500 is input / entered into the associated gas generator 501 through the first intermediate one-way valve 503 and the inlet one-way valve 502 in sequence to generate electricity.

[0120] In certain preferred embodiments, the method further comprises:

[0121] The step of emergency discharge of air; specifically comprising: when the oxygen content measured by the oxygen content detector 103 in the air intake unit 100 is higher than the first preset oxygen content threshold, opening the air intake emergency discharge valve 401 in the emergency discharge air unit 400 to perform emergency discharge of air; when the oxygen content measured by the oxygen content detector 103 is lower than the first preset oxygen content threshold, closing the air intake emergency discharge valve 401;

[0122] When the pressure value measured by the intake pressure transmitter 106 exceeds the first preset pressure threshold, the intake emergency exhaust valve 401 is opened / activated to perform emergency exhaust; when the pressure value measured by the intake pressure transmitter 106 is less than the first preset pressure threshold, the intake emergency exhaust valve 401 is closed;

[0123] When the flow rate measured by the air intake flow meter 101 exceeds the rated flow rate of the whole equipment, the air intake emergency exhaust valve 401 is opened / activated for emergency exhaust; when the flow rate measured by the air intake flow meter 101 is lower than the rated flow rate of the whole equipment, the air intake emergency exhaust valve 401 is closed;

[0124] When the pressure of the oil safety valve 404 in the emergency air discharge unit 400 exceeds its set pressure, the oil safety valve 404 is opened to discharge air urgently.

[0125] Another one-island type full-quantity recovery method for oilfield associated gas provided in this embodiment comprises the following steps:

[0126] The air intake step specifically includes: in the air intake unit 100, the oilfield associated gas drawn in enters the compression and delivery unit 200 through the air intake flow meter 101 and the air intake flame arrester 102;

[0127] The steps of compression and transportation include: the gas entering the compression and transportation unit 200 through the air intake unit 100 first passes through the air intake filter 201 for high-efficiency filtration and separation (to protect the gas compressor from impurities, and high-efficiency filtration and separation also requires a filtration level of not less than 10 μm), and then enters the moving equipment gas compressor 203 through the loading valve 202 for normal temperature compression and pressurization to a first compression and pressurization threshold (such as 0.8 MPa), and the pressurized gas enters the oil-gas separator 204 for gas and oil separation, and the separated gas is discharged from the first gas outlet of the oil-gas separator 204, and is transmitted to the air-cooled heat exchanger 2062 through the oil-gas one-way valve 205 for air-cooled heat exchange and cooling to room temperature, and then output to the pressurized condensing unit 300;

[0128] The step of pressurized condensation specifically includes: the pressurized normal temperature gas after being pressurized by the compression and delivery unit 200 enters the pressurized condensation unit 300, and first enters the air-cooled recovery heat exchanger 301 for air-to-air heat exchange and first-stage cooling (in this embodiment, air-to-air heat exchange and first-stage cooling are performed, and the temperature drops to about 15°C. Among them, the cold field temperature of the air-cooled recovery heat exchanger 301 is 15°C);

[0129] When the A-side branch is ventilated, the gas after primary cooling can enter the water removal heat exchanger A3021 through the air inlet cut-off valve A3061 for secondary cooling to separate free water or some heavy hydrocarbons, and then enter the pressurized condensation oil separation heat exchanger A3031 for tertiary cooling to separate supersaturated water or some light hydrocarbons, and then enter the oil-gas separator 304 through the air outlet cut-off valve A3071;

[0130] When the B-side branch is ventilated, the gas after the primary cooling can enter the water removal heat exchanger B3022 through the air inlet cut-off valve B3062 for secondary cooling to separate free water or some heavy hydrocarbons, and then enter the pressurized condensation oil separation heat exchanger B3032 for tertiary cooling to separate supersaturated water or some light hydrocarbons, and then enter the oil-gas separator 304 through the air outlet cut-off valve B3072;

[0131] The step of emergency discharge of air; specifically comprising: when the oxygen content measured by the oxygen content detector 103 in the air intake unit 100 is higher than the first preset oxygen content threshold (the first preset oxygen content threshold is adjustable, such as set to 5%), the air intake emergency discharge valve 401 in the emergency discharge air unit 400 is opened to discharge air urgently (the gas passes through the air intake emergency discharge valve 401 and then passes through the fire-blocking single call valve 402 for safe discharge); when the oxygen content measured by the oxygen content detector 103 is lower than the first preset oxygen content threshold (the first preset oxygen content threshold is adjustable, such as set to 5%), the air intake emergency discharge valve 401 is closed;

[0132] When the pressure value measured by the intake pressure transmitter 106 exceeds the first preset pressure threshold (the first preset pressure threshold is adjustable, such as set to 2500Pa), the intake emergency exhaust valve 401 is opened / activated for emergency exhaust (the gas passes through the intake emergency exhaust valve 401 and then safely exhausted through the fire-blocking single-call valve 402); when the pressure value measured by the intake pressure transmitter 106 is less than the first preset pressure threshold (the first preset pressure threshold is adjustable, such as set to 2500Pa), the intake emergency exhaust valve 401 is closed;

[0133] When the flow rate measured by the air inlet flow meter 101 exceeds the rated flow rate of the whole equipment (the rated flow rate of the whole equipment is an adjustable preset value, such as 3000m 3 / d), open / start the air intake emergency exhaust valve 401 for emergency exhaust (the gas passes through the air intake emergency exhaust valve 401 and then safely exhausts through the fire-blocking single-call valve 402); when the flow rate measured by the air intake flow meter 101 is lower than the rated flow rate of the whole equipment (the rated flow rate of the whole equipment is an adjustable preset value, such as 3000m 3 / d), close the air intake emergency exhaust valve 401;

[0134] When the pressure of the oil safety valve 404 in the emergency air discharge unit 400 exceeds its set pressure, the oil safety valve 404 is opened to discharge air urgently (the gas passes through the oil safety valve 404 and then through the fire-blocking single-call valve 402 for safe discharge);

[0135] Among them: the oil safety valve 404 is used to automatically open when the associated gas pressure is too high to release the pressure and ensure the safety of the system; in this embodiment, the set pressure of the oil safety valve 404 is set to 0.96MPa, and the excess pressure of the entire compression and delivery unit / system is discharged in time when overpressure occurs to prevent accidents;

[0136] The steps of dry gas power generation; specifically include: the associated gas dry gas output from the oil-gas separator 304 enters the air-cooled recovery heat exchanger 301 for cold recovery, and then is input into the dry gas power generation unit 500 and sequentially passes through the first intermediate one-way valve 503 and the inlet one-way valve 502 to enter / enter the associated gas generator 501 for power generation.

[0137] The oil field associated gas mentioned in this article refers to the natural gas that is extracted from underground oil layers along with crude oil during the process of oil extraction.

[0138] In this embodiment, the oilfield associated gas is fed with a pressure of about 1500 Pa. In this embodiment, the oilfield associated gas is usually fed continuously without gas supplementation, and the gas compressor 203 can work continuously.

[0139] In certain preferred embodiments, the method further comprises:

[0140] The step of collecting and recovering liquids; specifically comprising: the water or part of hydrocarbon liquid condensed and separated from the oilfield associated gas in the water removal heat exchanger A3021, the pressurized condensation oil separation heat exchanger A3031, the water removal heat exchanger B3022, the pressurized condensation oil separation heat exchanger B3032, and the oil-gas separator 304 respectively flows into the condensate tank 305 for collecting and recovering liquids (the liquid in the condensate tank 305 can be regularly discharged to the subsequent NGL processing unit through liquid level control. NGL is the abbreviation of Natural Gas Liquids, which refers to a liquid hydrocarbon mixture obtained by separation and condensation during the natural gas extraction and processing process); and / or

[0141] The steps of starting and stopping air cooling; specifically comprising: when the temperature measured by the air cooling temperature transmitter 207 is higher than the first preset air cooling threshold (the first preset air cooling threshold is adjustable, such as set to 40°C), the air cooling fan 2061 is turned on; when the temperature measured by the air cooling temperature transmitter 207 is lower than the second preset air cooling threshold (the second preset air cooling threshold is adjustable, such as set to 25°C), the air cooling fan 2061 is turned off; and / or

[0142] The steps of starting and stopping oil cooling include: when the temperature measured by the oil temperature transmitter 213 is higher than the first preset oil cooling threshold (the first preset oil cooling threshold is adjustable, such as set to 60°C), the oil cooling fan 2091 is turned on; when the temperature measured by the oil temperature transmitter 213 is lower than the second preset oil cooling threshold (the second preset oil cooling threshold is adjustable, such as set to 50°C), the oil cooling fan 2091 is turned off.

[0143] In certain preferred embodiments, the method further comprises:

[0144] The steps of chain alarm include:

[0145] When the pressure measured by the outlet pressure transmitter 208 is higher than a third preset pressure threshold (the third preset pressure threshold is adjustable, such as set to 0.88 MPa), an interlock alarm is triggered and the gas compressor 203 is shut down; and / or

[0146] When the liquid level measured by the liquid level transmitter 210 is lower than a first preset liquid level threshold (the first preset liquid level threshold is adjustable, such as set to 50 mm), an interlock alarm is triggered and the gas compressor 203 is shut down; and / or

[0147] When the oxygen content measured by the oxygen content detector 103 is higher than the first preset oxygen content threshold (the first preset oxygen content threshold is adjustable, such as set to 5%), the air intake emergency discharge valve 401 is opened for emergency discharge (the gas passes through the air intake emergency discharge valve 401 and then safely discharged through the fire-blocking single-call valve 402), and the interlocking alarm is triggered and the gas compressor 203 is shut down;

[0148] When the pressure value measured by the intake pressure transmitter 106 exceeds the first preset pressure threshold (the first preset pressure threshold is adjustable, such as set to 2500Pa), the intake emergency exhaust valve 401 is opened / activated for emergency exhaust (the gas passes through the intake emergency exhaust valve 401 and then safely exhausted through the fire-blocking single-call valve 402), and the interlocking alarm is triggered and the gas compressor 203 is shut down;

[0149] When the flow rate measured by the air inlet flow meter 101 exceeds the rated flow rate of the whole equipment (the rated flow rate of the whole equipment is an adjustable preset value, such as 3000m 3 / d), open / activate the air intake emergency exhaust valve 401 for emergency exhaust (the gas passes through the air intake emergency exhaust valve 401 and then through the fire-blocking single-call valve 402 for safe exhaust), and at the same time, set the alarm chain and shut down the gas compressor 203.

[0150] After the interlocking alarm is sounded and the gas compressor 203 is shut down, the system / process / device can be inspected / maintained / adjusted, and then the entire recovery system / process / device can be restarted as needed.

[0151] In this embodiment, in the step of pressurized condensation:

[0152] The associated gas dry gas outputted from the oil-gas separator 304 enters the air-cooled recovery heat exchanger 301 for cold recovery, and then passes through the first intermediate check valve 503 and the inlet check valve 502 in sequence to enter the associated gas generator 501 for power generation; thus completing the system flow of associated gas from air intake, compression and transportation, pressurization and condensation to dry gas power generation;

[0153] Among them, the cold source of the water removal heat exchanger A3021 is provided by the first refrigeration compressor 3111; the cold source of the pressurized condensing oil separation heat exchanger A3031 is provided by the second refrigeration compressor 3121; the cold source of the water removal heat exchanger B3022 is provided by the third refrigeration compressor 3112; the cold source of the pressurized condensing oil separation heat exchanger B3032 is provided by the fourth refrigeration compressor 3122;

[0154] Among them, the power supply required by the moving parts such as the first refrigeration compressor 3111, the second refrigeration compressor 3121, the third refrigeration compressor 3112, the fourth refrigeration compressor 3122, the gas compressor 203, the air-cooling fan 2061, and the oil-cooling fan 2091, and the control power supply required by each valve and each instrument are all provided by the associated gas generator 501, thereby realizing the island operation of the entire device / system (that is, the entire device / system does not require external power supply and operates in an island).

[0155] In some embodiments, the emergency exhaust valve 403 is a normally open valve (FO). The symbol of the normally open valve is FO. When the normally open valve is powered off, the valve is in an open state, and its opening and closing can be controlled according to the power on and off.

[0156] In this embodiment, when the oil field associated gas is first introduced, it first passes through the intake flow meter 101, the intake flame arrester 102, the exhaust emergency valve 403, the second intermediate one-way valve 504, and the inlet one-way valve 502, and enters the associated gas generator 501 for power generation. After generating electricity, it can provide power supply for the entire system.

[0157] Among them, when the associated gas generator 501 obtains gas to generate electricity, the refrigeration compressor of the A side branch or the B side branch can be started to establish the cold field temperature of the water removal heat exchanger and the pressurized condensation oil separation heat exchanger of the corresponding branch. After the cold field temperature is established, the outlet emergency exhaust valve 403 is closed, the gas compressor 203 is started, and the air intake shut-off valve and the air outlet shut-off valve of the corresponding branch are opened. The system operation process of oilfield associated gas intake, compression and transportation, pressurization and condensation and dry gas power generation is carried out.

[0158] In this embodiment, the power generation of the associated gas generator 501×0.8≥(the sum of the maximum power consumption of all electrical equipment such as the first refrigeration compressor 3111, the second refrigeration compressor 3121, the third refrigeration compressor 3112, the fourth refrigeration compressor 3122, the gas compressor 203, the air-cooling fan 2061, the oil-cooling fan 2091, and each valve in the system and each instrument in the system)×120%.

[0159] In certain preferred embodiments, the first preset oxygen content threshold is adjustable. In this embodiment, the first preset oxygen content threshold is set to 5%.

[0160] In certain preferred embodiments, the first preset pressure threshold is adjustable. In this embodiment, the first preset pressure threshold is set to 2500Pa.

[0161] In some preferred embodiments, the rated flow rate of the whole machine is adjustable. In this embodiment, the rated flow rate of the whole machine is set to 3000m 3 / d.

[0162] In some preferred embodiments, the set pressure of the oil safety valve 404 is set to 0.96Mpa. In case of overpressure, specifically, when the pressure of the oil safety valve 404 exceeds its set pressure, the oil safety valve 404 is opened, and the gas is discharged from the exhaust port of the safety valve, and the excess pressure of the entire compression and delivery system / compression and delivery unit is discharged in time to prevent the entire system from continuing to increase pressure, effectively preventing accidents. Of course, in some embodiments, the set pressure of the oil safety valve 404 can also be set to 0.96±0.03Mpa.

[0163] In certain preferred embodiments, the third preset pressure threshold is adjustable. In this embodiment, the third preset pressure threshold is set to 0.88 MPa.

[0164] In certain preferred embodiments, the first preset liquid level threshold is adjustable. In this embodiment, the first preset liquid level threshold is set to 50 mm.

[0165] In certain preferred embodiments, the first preset air cooling threshold is adjustable. In this embodiment, the first preset air cooling threshold is set to 40°C.

[0166] In certain preferred embodiments, the second preset air cooling threshold is adjustable. In this embodiment, the second preset air cooling threshold is set to 25°C.

[0167] In certain preferred embodiments, the first preset oil cooling threshold is adjustable. In this embodiment, the first preset oil cooling threshold is set to 60°C.

[0168] In certain preferred embodiments, the second preset oil cooling threshold is adjustable. In this embodiment, the second preset oil cooling threshold is set to 50°C.

[0169] In some preferred embodiments, specifically, the A side branch and the B side branch are switched regularly according to a set time period, T is the regular switching time period, and T is adjustable;

[0170] In this embodiment, the time period T of the timed switching between side A and side B is set to 4, that is, one cycle is 4 hours. The pressurized condensing unit adopts a dual branch channel. When one branch / channel is working, the other branch / channel automatically enters the defrosting process to eliminate ice blockage. In this way, the dual branches / channels are periodically and uninterruptedly switched, which can effectively ensure that the air intake unit continuously intakes air, and the entire process / system / equipment can meet 24-hour continuous operation.

[0171] In this embodiment, when the A side branch is ventilated, the air intake cut-off valve A3061 and the air outlet cut-off valve A3071 are opened; when the A side branch is not ventilated, the air intake cut-off valve A3061 and the air outlet cut-off valve A3071 are closed.

[0172] In this embodiment, when the B side branch is ventilated, the air intake cut-off valve B3062 and the air outlet cut-off valve B3072 are opened; when the B side branch is not ventilated, the air intake cut-off valve B3062 and the air outlet cut-off valve B3072 are closed.

[0173] Among them, the air inlet cut-off valve A3061 and the air outlet cut-off valve A3071 on the A-side branch are opened and closed at the same time;

[0174] Among them, the air intake cut-off valve B3062 and the air outlet cut-off valve B3072 on the B side branch are opened and closed at the same time.

[0175] In certain preferred embodiments, specifically, after the associated gas generator 501 obtains gas for the first time to generate electricity, and the A side branch is selected for ventilation, the first refrigeration compressor 3111 and the second refrigeration compressor 3121 on the A side branch are started to establish the cold field temperature of the dehydration heat exchanger A3021 (+5°C cold field) and the pressurized condensation oil separation heat exchanger A3031 (-35°C cold field); (The first cold field temperature establishment takes about 30 minutes, and the dehydration heat exchanger A3021 reaches the first-level cold field temperature such as +5°C in about 30 minutes, and the pressurized condensation oil separation heat exchanger A3031 reaches the second-level cold field temperature such as -35°C.) After the first cold field temperature is established, the outlet emergency exhaust valve 403 is closed, the gas compressor 203 is started, and the air intake shut-off valve A3061 and the air outlet shut-off valve A3071 are opened, and the oilfield associated gas undergoes the conventional system operation process of air intake, compression and transportation, pressurization and condensation, and dry gas power generation.

[0176] In certain preferred embodiments, specifically, after the associated gas generator 501 obtains gas for the first time to generate electricity, and the B-side branch is selected for ventilation, the third refrigeration compressor 3112 and the fourth refrigeration compressor 3122 on the B-side branch are started to establish the cold field temperature of the dehydration heat exchanger B3022 (+5°C cold field) and the pressurized condensation oil separation heat exchanger B3032 (-35°C cold field); (The first cold field temperature establishment takes about 30 minutes, and the dehydration heat exchanger A3021 reaches the first-level cold field temperature such as +5°C in about 30 minutes, and the pressurized condensation oil separation heat exchanger A3031 reaches the second-level cold field temperature such as -35°C.) After the first cold field temperature is established, the outlet emergency exhaust valve 403 is closed, the gas compressor 203 is started, and the air intake shut-off valve B3062 and the air outlet shut-off valve B3072 are opened, and the oilfield associated gas undergoes the conventional system operation process of air intake, compression and transportation, pressurization and condensation, and dry gas power generation.

[0177] In this embodiment, when the associated gas generator 501 is continuously generating gas, such as switching between the A-side branch and the B-side branch, before switching, the refrigeration compressor of the other branch (the branch to be ventilated) is first started to establish the cold field temperature of the water removal heat exchanger and the pressurized condensation oil separation heat exchanger of the corresponding branch. After the cold field temperature is established, the air inlet shut-off valve and the air outlet shut-off valve of the original ventilation branch are closed, and the air inlet shut-off valve and the air outlet shut-off valve of the branch to be ventilated are opened / opened, so as to realize seamless and flexible switching of the bilateral branches, and realize the intake, compression, transportation and pressurization of the oil field associated gas. Continuous operation of condensation and dry gas power generation; the original ventilation branch that is switched (that is, closed) is switched from refrigeration mode to defrost mode (the associated gas contains trace amounts of moisture, which will freeze and block the gas channel below zero degrees. Regular defrosting and unblocking are required to ensure that the gas channel is unobstructed during the next cycle of air intake and the system equipment operates continuously). After the defrost is completed, the branch is shut down until the next branch switching, when the refrigeration compressor of the branch is started again to enter the refrigeration mode, and the cold field temperature of the dehydration heat exchanger and the pressurized condensation oil separation heat exchanger of the branch is established; and the cycle operation is alternating like this.

[0178] In certain preferred embodiments, specifically, when the associated gas generator 501 is continuously generating electricity, such as switching from the A-side branch to the B-side branch, before switching, the third refrigeration compressor 3112 and the fourth refrigeration compressor 3122 on the B-side branch are started first, and the cold field temperature of the water removal heat exchanger B3022 (+5°C cold field) and the pressurized condensing oil separation heat exchanger B3032 (-35°C cold field) are established. After the cold field temperature is established, the air inlet shut-off valve B3062 and the air outlet shut-off valve B3072 of the B-side branch are opened / opened, and the air inlet shut-off valve A3061 and the air outlet shut-off valve A3071 of the A-side branch are closed, so as to achieve A The side branch is seamlessly switched to the B side branch, thereby realizing the continuous operation of oilfield associated gas intake, compression and transportation, pressurization and condensation, and dry gas power generation; the A side branch that is switched (that is, closed) is switched from the cooling mode to the defrosting mode. After the defrosting is completed, the first refrigeration compressor 3111 and the second refrigeration compressor 3121 of the A side branch are shut down until the next branch switching, and the first refrigeration compressor 3111 and the second refrigeration compressor 3121 of the A side branch are restarted to enter the cooling mode to establish the cold field temperature of the A side branch dehydration heat exchanger A3021 and the pressurization condensation oil separation heat exchanger A3031; and the cycle operation is alternating like this.

[0179] In certain preferred embodiments, specifically, when the associated gas generator 501 is continuously generating electricity, such as switching from the B-side branch to the A-side branch, before switching, the first refrigeration compressor 3111 and the second refrigeration compressor 3121 on the A-side branch are started first to establish the cold field temperature of the water removal heat exchanger A3021 (+5°C cold field) and the pressurized condensing oil separation heat exchanger A3031 (-35°C cold field). After the cold field temperature is established, the air inlet shut-off valve A3061 and the air outlet shut-off valve A3071 of the A-side branch are opened / opened, and the air inlet shut-off valve B3062 and the air outlet shut-off valve B3072 of the B-side branch are closed to achieve B The side branch is seamlessly switched to the A side branch, thereby realizing the continuous operation of oilfield associated gas intake, compression and transportation, pressurization and condensation, and dry gas power generation; the switched (i.e., closed) B side branch is switched from refrigeration mode to defrost mode, and after the defrost is completed, the third refrigeration compressor 3112 and the fourth refrigeration compressor 3122 of the B side branch are shut down until the next branch switching, and the third refrigeration compressor 3112 and the fourth refrigeration compressor 3122 of the B side branch are restarted to enter the refrigeration mode, and the cold field temperature of the B side branch dehydration heat exchanger B3022 and the pressurization condensation oil separation heat exchanger B3032 is established; and the cycle operation is alternating like this.

[0180] In certain preferred embodiments, specifically, the step of dry gas power generation also includes: when the oilfield associated gas is first introduced, the oilfield associated gas is successively / sequentially passed through the intake flow meter 101, the intake flame arrester 102, the outlet emergency exhaust valve 403, the second intermediate one-way valve 504, and the inlet one-way valve 502, and is input / entered into the associated gas generator 501 for power generation, and after generating electricity, it can provide power supply for the entire system.

[0181] When the associated gas processing capacity of the oil field exceeds the maximum power distribution demand of the system, the remaining associated gas dry gas can be output to external equipment through the self-operated regulating valve 507, the outlet check valve 508 and the outlet flame arrester 506 in sequence, such as output to the subsequent pipeline network, power generation, LNG or CNG processing unit;

[0182] Among them: LNG is the abbreviation of Liquefied Natural Gas, which means liquefied natural gas. It is the product of natural gas that has been purified and cooled and liquefied at ultra-low temperatures (such as -162°C).

[0183] Among them: CNG is the abbreviation of Compressed Natural Gas, which means compressed natural gas. It refers to gaseous natural gas compressed to a pressure greater than or equal to 10MPa and not greater than 25MPa. The natural gas is pressurized and stored in a container in a gaseous state.

[0184] In this embodiment, the associated gas processing capacity of the oil field is 3000m 3 / d, producing dry gas of about 3000m3 / d×70%=2100m 3 / d=87.5m 3 / h, the power generation capacity (gas: electricity = 1:3) is 87.5×3=262.5kWh, and the maximum power distribution of the calculated power equipment is 50kW (corresponding to 17m dry gas 3 / h), considering the margin, choose 80kW generator, it can be seen that there is about 70m 3 / h dry gas cannot be used, that is, the processing capacity of the oil field associated gas exceeds the maximum power distribution demand of the system.

[0185] In this embodiment, the outlet flame arrester 506 is used to prevent the spread of outlet flame; the self-controlled regulating valve 505 is arranged in parallel with the self-operated regulating valve 507 to improve the reliability of the regulating valve; the inlet check valve 502, the first intermediate check valve 503, the second intermediate check valve 504 and the outlet check valve 508 are used to ensure the correct flow direction of gas and prevent gas backflow.

[0186] In this embodiment, the pre-valve pressure threshold of the self-operated regulating valve 507 is set to about 0.7 MPa. In the present invention, the pre-valve pressure threshold of the self-operated regulating valve 507 is adjustable, such as being adjusted according to the pipe network pressure and set to 0.7 MPa±0.1 MPa.

[0187] In this embodiment, the pre-valve pressure threshold of the automatic regulating valve 505 is set to about 0.7 MPa. In the present invention, the pre-valve pressure threshold of the automatic regulating valve 505 is adjustable, such as being adjusted according to the pipe network pressure and set to 0.7 MPa±0.1 MPa.

[0188] In certain preferred embodiments, in the above-mentioned compression and transportation step: the temperature of the gas after being pressurized by the gas compressor 203 is between 60 and 80°C, and then it is cooled to a normal temperature of about 45°C by the air-cooled heat exchanger 2062.

[0189] In certain preferred embodiments, the first compression pressure threshold is set to 0.8 MPa.

[0190] In some preferred embodiments, the oil and gas one-way valve 205 is a mechanical one, and its pressure setting value is 0.4 MPa.

[0191] In certain preferred embodiments, the pre-valve pressure threshold of the self-operated regulating valve 507 is adjustable and is set to 0.7 MPa.

[0192] In certain preferred embodiments, the pre-valve pressure threshold of the automatic regulating valve 505 is adjustable and is set to 0.7 MPa.

[0193] In certain preferred embodiments, the cold field temperature of the water removal heat exchanger A3021 is +5°C.

[0194] In certain preferred embodiments, the cold field temperature of the pressurized condensing oil separation heat exchanger A3031 is -35°C.

[0195] In certain preferred embodiments, the cold field temperature of the dewatering heat exchanger B3022 is +5°C.

[0196] In certain preferred embodiments, the cold field temperature of the pressurized condensing oil separation heat exchanger B3032 is -35°C.

[0197] In certain preferred embodiments, the cold field temperature of the air-cooled recovery heat exchanger 301 is 15°C.

[0198] In certain preferred embodiments, the air outlet emergency exhaust valve 403 is a normally open valve.

[0199] In this embodiment, the gas compressor used is a variable frequency single-screw compressor, combined with oil injection and exhaust cooling, the exhaust temperature is no higher than 45°C, and the system is safe and reliable for normal temperature transportation.

[0200] Any of the above-mentioned methods for the full-quantity recovery of oilfield associated gas, which is used for the full-quantity recovery system of oilfield associated gas, such as Figure 1 As shown, the system includes an air intake unit 100, a compression and transportation unit 200, a pressurized condensation and separation unit 300, an emergency air discharge unit 400 and a dry gas power generation unit 500.

[0201] Specifically, Figure 1 As shown, the above-mentioned single-island type fully quantitative recovery system for oilfield associated gas includes an air intake unit 100, a compression and conveying unit 200 connected to the gas phase pipeline of the air intake unit 100, a pressurized condensing unit 300 connected to the gas phase pipeline of the compression and conveying unit 200, a dry gas power generation unit 500 connected to the gas phase pipeline of the pressurized condensing unit 300, and an emergency discharge air unit 400 connected to the gas phase pipelines of the air intake unit 100, the compression and conveying unit 200 and the dry gas power generation unit 500.

[0202] It can also be said that the island-type fully quantitative recovery system for oilfield associated gas includes an air intake unit 100, a compression and delivery unit 200 connected to the gas phase pipeline of the air intake unit 100, a pressurized condensation unit 300 connected to the gas phase pipeline of the compression and delivery unit 200, an emergency air discharge unit 400 connected to the gas phase pipelines of the air intake unit 100 and the compression and delivery unit 200, and a dry gas power generation unit 500 connected to the gas phase pipelines of the pressurized condensation unit 300 and the emergency air discharge unit 400. Each unit is interconnected through pipelines and valves to form a complete oilfield associated gas recovery system.

[0203] In the single-island type fully quantitative recovery system for oilfield associated gas provided in this embodiment, specifically, the air intake unit 100 includes an air intake flow meter 101 and an air intake flame arrester 102 connected to the air outlet end of the air intake flow meter 101 .

[0204] The oilfield associated gas inlet of the system is connected to the inlet end of the air intake flow meter 101 .

[0205] In this embodiment, specifically, an intake pressure transmitter 106 is provided on the pipeline connecting the oilfield associated gas inlet and the inlet end of the intake flowmeter 101; an oxygen content detector 103 is provided on the pipeline connecting the outlet of the intake flame arrester 102 and the compression and delivery unit 200.

[0206] In the single-island type fully quantitative recovery system for oilfield associated gas provided in this embodiment, specifically, the gas phase pipeline of the compression and delivery unit 200 includes an air intake filter 201, a loading valve 202 connected to the outlet end of the air intake filter 201, a gas compressor 203 connected to the outlet end of the loading valve 202, an oil-gas separator 204 connected to the outlet end of the gas compressor 203, an oil-gas check valve 205 connected to the first gas outlet end of the oil-gas separator 204, a reflux cut-off valve 214 connected to the second gas outlet end of the oil-gas separator 204, and an air-cooled heat exchanger 2062 connected to the outlet end of the oil-gas check valve 205;

[0207] The other end of the reflux cut-off valve 214 is connected to the inlet end of the loading valve 202. In other words, the other end of the reflux cut-off valve 214 is connected to the inlet end of the loading valve 202 and the outlet end (i.e., the gas outlet end) of the air intake filter 201, and the gas is output from the other end of the reflux cut-off valve 214 and / or the outlet end of the air intake filter 201 to the inlet end of the loading valve 202.

[0208] When the air intake of the gas compressor 203 is unstable, the reflux can be adjusted through the reflux cut-off valve 214. That is, the reflux is adjusted by opening the bypass where the reflux cut-off valve 214 is located.

[0209] In this embodiment, the outlet end of the air-cooled heat exchanger 2062 is connected to the hot side air path inlet of the air-cooled recovery heat exchanger 301 in the pressurized condensing unit 300; the inlet end of the air intake filter 201 is connected to the outlet of the air intake flame arrester 102 in the air intake unit 100.

[0210] In certain preferred embodiments, an oil temperature transmitter 213 is provided on the pipeline connecting the outlet of the gas compressor 203 and the inlet of the oil-gas separator 204 .

[0211] In certain preferred embodiments, an air-cooled temperature transmitter 207 and an outlet air pressure transmitter 208 are provided on the outlet pipeline of the air-cooled heat exchanger 2062 .

[0212] In certain preferred embodiments, a liquid level transmitter 210 is provided at the liquid storage portion (also referred to as a liquid storage portion) at the lower portion of the oil-gas separator 204 .

[0213] In the single-island type full-quantity recovery system for oilfield associated gas provided in this embodiment, specifically, the oil phase pipeline of the compression and conveying unit 200 includes an oil-gas separator 204, an oil-cooling heat exchanger 2092 connected to the oil outlet end of the oil-gas separator 204, an oil filter 211 connected to the outlet end of the oil-cooling heat exchanger 2092, and an oil shut-off valve 212 connected to the outlet end of the oil filter 211; the other end of the oil shut-off valve 212 is connected to the oil return port (also called the oil phase pipeline inlet) of the gas compressor 203.

[0214] In the single-island type fully quantitative recovery system for oilfield associated gas provided in this embodiment, specifically, the pressurized condensing unit 300 includes an air-cooled recovery heat exchanger 301; and

[0215] An air inlet shut-off valve A3061 located on the A side branch connected to the hot side air outlet of the air-cooled recovery heat exchanger 301, a dehydration heat exchanger A3021 connected to the air outlet of the air inlet shut-off valve A3061, a pressurized condensing oil separation heat exchanger A3031 connected to the air outlet of the dehydration heat exchanger A3021, and an air outlet shut-off valve A3071 connected to the air outlet of the pressurized condensing oil separation heat exchanger A3031; and

[0216] An air inlet shut-off valve B3062 located on the B side branch and connected to the hot side air outlet of the air-cooled recovery heat exchanger 301, a dehydration heat exchanger B3022 connected to the air outlet end of the air inlet shut-off valve B3062, a pressurized condensing oil separation heat exchanger B3032 connected to the air outlet end of the dehydration heat exchanger B3022, and an air outlet shut-off valve B3072 connected to the air outlet end of the pressurized condensing oil separation heat exchanger B3032.

[0217] In this embodiment, specifically, the pressurized condensing unit 300 also includes an oil-gas separator 304 ; the outlet end of the outlet shut-off valve A 3071 and the outlet end of the outlet shut-off valve B 3072 are both connected to the inlet end of the oil-gas separator 304 .

[0218] Among them, the air inlet end of the air inlet shut-off valve A3061 located on the A side branch and the air inlet end of the air inlet shut-off valve B3062 located on the B side branch are both connected to the hot side air outlet of the air-cooled recovery heat exchanger 301.

[0219] The gas outlet end of the oil-gas separator 304 is connected to the cold side gas path inlet of the air-cooled recovery heat exchanger 301 .

[0220] The cold side gas path outlet of the air-cooled recovery heat exchanger 301 is connected to the inlet end of the first intermediate one-way valve 503 .

[0221] In certain preferred embodiments, the outlet end of the air outlet shut-off valve A3071 and the outlet end of the air outlet shut-off valve B3072 are merged and connected to the air inlet end of the oil-gas separator 304, and the outlet end of the oil-gas separator 304 is connected to the cold side air path inlet of the air-cooled recovery heat exchanger 301.

[0222] Among them, the air inlet end of the air inlet shut-off valve A3061 located on the A side branch and the air inlet end of the air inlet shut-off valve B3062 located on the B side branch are both connected to the hot side air outlet of the air-cooled recovery heat exchanger 301; the A side branch and the B side branch are two parallel air branches separated after the hot side air outlet of the air-cooled recovery heat exchanger 301.

[0223] The A side gas path described herein may also be referred to as the A side branch or the first branch or the first gas path, or simply referred to as the A path or gas path A. The B side gas path described herein may also be referred to as the B side branch or the second branch or the second gas path, or simply referred to as the B path or gas path B. The air intake cut-off valve described herein may also be referred to as the air intake switching valve. The air outlet cut-off valve described herein may also be referred to as the air outlet switching valve.

[0224] In the single-island type fully quantitative recovery system for oilfield associated gas provided in this embodiment, specifically, the pressurized condensing unit 300 also includes a first refrigeration compressor 3111, a second refrigeration compressor 3121, a third refrigeration compressor 3112, a fourth refrigeration compressor 3122 and a condensate tank 305.

[0225] Among them: the cold source of the dewatering heat exchanger A3021 is provided by the first refrigeration compressor 3111; the cold source of the pressurized condensing oil separation heat exchanger A3031 is provided by the second refrigeration compressor 3121; the cold source of the dewatering heat exchanger B3022 is provided by the third refrigeration compressor 3112; the cold source of the pressurized condensing oil separation heat exchanger B3032 is provided by the fourth refrigeration compressor 3122. It can also be said that the pressurized condensing unit 300 also includes the first refrigeration compressor 3111 providing a cold source for the dewatering heat exchanger A3021, the second refrigeration compressor 3121 providing a cold source for the pressurized condensing oil separation heat exchanger A3031, the third refrigeration compressor 3112 providing a cold source for the dewatering heat exchanger B3022, the fourth refrigeration compressor 3122 providing a cold source for the pressurized condensing oil separation heat exchanger B3032, and the condensate tank 305.

[0226] The liquid outlet ends of the water removal heat exchanger A3021, the pressurized condensing oil separation heat exchanger A3031, the water removal heat exchanger B3022, the pressurized condensing oil separation heat exchanger B3032, and the oil-gas separator 304 are all connected to the liquid inlet end of the condensate tank 305.

[0227] In the single-island type fully quantitative recovery system for oilfield associated gas provided in this embodiment, specifically, the emergency discharge air unit 400 includes an air intake emergency discharge valve 401, an oil separation safety valve 404 and an air outlet emergency discharge valve 403;

[0228] The inlet end (i.e., the air inlet end or the air inlet end) of the air inlet emergency exhaust valve 401 is connected to the outlet of the air inlet flame arrester 102 in the air inlet unit 100;

[0229] The inlet end of the oil safety valve 404 is connected to the third outlet end of the oil-gas separator 204;

[0230] The inlet end of the air outlet emergency exhaust valve 403 is connected to the outlet of the air intake flame arrester 102 in the air intake unit 100;

[0231] The outlet end (i.e., the outlet end) of the air intake emergency exhaust valve 401 is connected to the inlet end of the fire-blocking single-call valve 402;

[0232] The outlet of the oil safety valve 404 is connected to the inlet of the fire-blocking single-call valve 402;

[0233] The outlet end of the gas emergency exhaust valve 403 is connected to the inlet end of the second intermediate check valve 504 in the dry gas power generation unit 500;

[0234] The outlet end of the fire-blocking single-call valve 402 is used for exhaustion.

[0235] That is, the emergency exhaust unit 400 includes an air intake emergency exhaust valve 401, a fire-blocking single-call valve 402 connected to the air outlet end of the air intake emergency exhaust valve 401, an oil separation safety valve 404 connected to the third air outlet end of the oil-gas separator 204, and an air outlet emergency exhaust valve 403 connected to the air inlet end of the air intake emergency exhaust valve 401;

[0236] The inlet end (i.e., the air inlet end or the air inlet end) of the air inlet emergency exhaust valve 401 is connected to the outlet of the air inlet flame arrester 102 in the air inlet unit 100;

[0237] It can also be said that: the outlet of the air intake flame arrester 102 in the air intake unit 100 is connected to the inlet end (i.e., the air inlet end) of the air intake emergency exhaust valve 401 and the inlet end (i.e., the air inlet end) of the air outlet emergency exhaust valve 403 at the same time;

[0238] The outlet of the oil safety valve 404 is connected to the inlet of the fire-blocking single-call valve 402;

[0239] The outlet end of the emergency exhaust valve 403 is connected to the inlet end of the second intermediate check valve 504 in the dry gas power generation unit 500; the outlet end of the fire-blocking single-call valve 402 is used for exhaust.

[0240] In the single-island type full-quantity recovery system for oilfield associated gas provided in this embodiment, specifically, the dry gas power generation unit 500 includes a first intermediate one-way valve 503, an inlet one-way valve 502 connected to the outlet end of the first intermediate one-way valve 503, an inlet associated gas generator 501 connected to the outlet end of the inlet one-way valve 502, a self-operated regulating valve 507 connected to the outlet end of the first intermediate one-way valve 503, a gas outlet one-way valve 508 connected to the outlet end of the self-operated regulating valve 507, a gas outlet flame arrester 506 connected to the outlet end of the gas outlet one-way valve 508, and a second intermediate one-way valve 504 connected to the outlet end of the gas outlet emergency exhaust valve 403; that is: the inlet end of the second intermediate one-way valve 504 is connected to the outlet end of the gas outlet emergency exhaust valve 403; the other end (that is, the outlet end) of the second intermediate one-way valve 504 is connected / communicated with the inlet end of the inlet one-way valve 502.

[0241] Wherein: the inlet end of the first intermediate non-return valve 503 is connected to the cold side gas path outlet of the air-cooled recovery heat exchanger 301 .

[0242] In some preferred embodiments, the dry gas power generation unit 500 further includes an automatic control valve 505 connected in parallel with both ends of the self-operated control valve 507;

[0243] The other end (i.e., the outlet end) of the second intermediate one-way valve 504 is connected / communicated with the outlet end of the first intermediate one-way valve 503, the inlet end of the inlet one-way valve 502, the inlet end of the self-operated regulating valve 507, and the inlet end of the automatic regulating valve 505; the outlet end of the self-operated regulating valve 507 and the outlet end of the automatic regulating valve 505 are connected / communicated with the inlet end of the gas outlet one-way valve 508.

[0244] In this embodiment, the outlet end of the gas outlet flame arrester 506 is used to output to external equipment, such as output to a pipeline network, output for power generation, output to make LNG, CNG and other subsequent peripheral devices / systems.

[0245] In some preferred embodiments, the air-cooled heat exchanger 2062 is equipped with an air-cooled fan 2061. In some preferred embodiments, the oil-cooled heat exchanger 2092 is equipped with an oil-cooled fan 2091.

[0246] In some preferred embodiments, the gas compressor 203 uses a variable frequency single screw.

[0247] In certain preferred embodiments, the backflow cut-off valve 214 is interlocked with the gas compressor 203 .

[0248] In certain preferred embodiments, the air-cooling temperature transmitter 207 is interlockedly controlled with the air-cooling fan 2061 .

[0249] In certain preferred embodiments, the oil temperature transmitter 213 is interlocked with the oil cooling fan 2091 .

[0250] In certain preferred embodiments, both the outlet gas pressure transmitter 208 and the liquid level transmitter 210 are interlocked with the gas compressor 203 .

[0251] In certain preferred embodiments, the oxygen content detector 103 , the intake air pressure transmitter 106 and the intake air flow meter 101 are all interlocked with the gas compressor 203 .

[0252] In certain preferred embodiments, the oxygen content detector 103 , the intake pressure transmitter 106 and the intake flow meter 101 are all interlocked with the intake emergency exhaust valve 401 .

[0253] The full quantification (meaning full energyization) mentioned in the text can also be called full energyization. It can also be said to be full energyization, which can be referred to as full quantification, which means that in the oil field associated gas recovery process / method / system / device of the present invention, on the one hand, liquid condensate oil is recovered, and on the other hand, gas is used for power generation, and the oil field associated gas recovery is fully converted into energy to the maximum extent.

[0254] In the present invention, the interlocking control between the components, the opening / closing / starting / stopping of the components, the switching / conversion / adjustment of the operation modes (including the switching / conversion / adjustment of the operation modes related to the A-side branch and the B-side branch, etc.), the opening and closing or the opening adjustment of the related valves can be performed manually, or the automatic switching / control / adjustment can be realized through the PLC control logic. The automatic switching / control / adjustment here can be realized by the conventional control logic in the prior art, which will not be described in detail. In some preferred embodiments, various transmitters and / or sensors can be further combined to realize the automatic switching / conversion / adjustment of the related operation modes.

[0255] The gas pipelines described herein are connected, which can also be referred to as gas lines; the gas pipelines described herein can also be referred to as gas pipelines. The oil pipelines described herein can also be referred to as oil pipelines. The interlocking control described herein can also be referred to as interlocking control. The inlet / outlet described herein can also be referred to as inlet / outlet, or inlet / outlet end.

[0256] ***A mentioned in the text can also be called A-line ***. ***B mentioned in the text can also be called B-line ***. "***" can be a water removal heat exchanger, a pressurized condensing oil separation heat exchanger, an air inlet shut-off valve, an air outlet shut-off valve, etc.

[0257] The Dokdo-type fully quantified recovery system for oilfield associated gas described herein may also be referred to as a Dokdo-type quantified recovery system for / based on oilfield associated gas, or a Dokdo-type recovery system for / based on oilfield associated gas. The Dokdo-type fully quantified recovery method for oilfield associated gas described herein may also be referred to as a Dokdo-type quantified recovery method for / based on oilfield associated gas, or a Dokdo-type recovery method for / based on oilfield associated gas. The full quantification (meaning full energyization) described herein may also be referred to as full energyization, or simply quantification.

[0258] The Dokdo-type full-quantity recycling system described herein may also be referred to as the Dokdo-type full-quantity recycling device, the Dokdo-type quantitative recycling device, or the Dokdo-type recycling device. The “ / ” described herein means or.

[0259] The above embodiments do not limit the present invention. Various changes and modifications made by relevant personnel without departing from the technical concept of the present invention are all within the protection scope of the present invention.

Claims

1. A Dokdo-type fully quantitative recovery method for oilfield associated gas, characterized in that: The system is a one-island type fully quantitative recovery system for oilfield associated gas, the system comprising an air intake unit (100), a compression and transportation unit (200), a pressurized condensation separation unit (300), an emergency air discharge unit (400) and a dry gas power generation unit (500); the method comprises the following steps: The air intake step specifically comprises: in the air intake unit (100), the oilfield associated gas drawn in enters the compression and delivery unit (200) through the air intake flow meter (101) and the air intake flame arrester (102); The step of compression and transportation specifically comprises: the gas entering the compression and transportation unit (200) through the air intake unit (100) is first filtered and separated by the air intake filter (201), and then enters the moving equipment gas compressor (203) for compression and pressurization at room temperature, the pressurized gas enters the oil-gas separator (204) for separation of gas and oil, and the separated gas is sent to the air-cooled heat exchanger (2062) for air-cooled heat exchange and cooled to room temperature, and then output to the pressurized condensing unit (300); The step of pressurized condensation specifically comprises: the pressurized gas at room temperature after being pressurized by the compression and delivery unit (200) enters the pressurized condensation unit (300), and first enters the air-cooled recovery heat exchanger (301) for gas-to-gas heat exchange and primary cooling; When a branch is ventilated, the gas after primary cooling can enter the dehydration heat exchanger of the branch for secondary cooling to separate free water or part of heavy hydrocarbons, and then enter the pressurized condensation oil separation heat exchanger of the branch for tertiary cooling to separate supersaturated water or part of light hydrocarbons, and then enter the oil-gas separator (304) through the outlet cut-off valve of the branch; The step of dry gas power generation specifically comprises: the associated dry gas input into the dry gas power generation unit (500) is sequentially input into the associated gas generator (501) through the first intermediate one-way valve (503) and the inlet one-way valve (502) to generate electricity.

2. The method for recovering associated gas from an oil field using a single island method according to claim 1, characterized in that: Also includes: The step of emergency air discharge comprises: when the oxygen content measured by the oxygen content detector (103) in the air intake unit (100) is higher than a first preset oxygen content threshold, opening the air intake emergency discharge valve (401) in the emergency air discharge unit (400) to discharge air urgently; when the oxygen content measured by the oxygen content detector (103) is lower than the first preset oxygen content threshold, closing the air intake emergency discharge valve (401); When the pressure value measured by the intake pressure transmitter (106) exceeds a first preset pressure threshold, the intake emergency exhaust valve (401) is opened / activated to perform emergency exhaust; when the pressure value measured by the intake pressure transmitter (106) is less than the first preset pressure threshold, the intake emergency exhaust valve (401) is closed; When the flow rate measured by the air intake flow meter (101) exceeds the rated flow rate of the whole equipment, the air intake emergency exhaust valve (401) is opened / activated to perform emergency exhaust; when the flow rate measured by the air intake flow meter (101) is lower than the rated flow rate of the whole equipment, the air intake emergency exhaust valve (401) is closed; When the pressure of the oil safety valve (404) in the emergency air discharge unit (400) exceeds its set pressure, the oil safety valve (404) is opened to perform emergency air discharge.

3. The one-island type full-quantity recovery method for oilfield associated gas according to claim 1, characterized in that: Also includes: The step of collecting and recovering liquids includes: the water or part of hydrocarbon liquid condensed and separated from the oilfield associated gas in the water removal heat exchanger A (3021), the pressurized condensation oil separation heat exchanger A (3031), the water removal heat exchanger B (3022), the pressurized condensation oil separation heat exchanger B (3032), and the oil-gas separator (304) flows into the condensate tank (305) for collecting and recovering liquids; and / or The air cooling start and stop step specifically comprises: when the temperature measured by the air cooling temperature transmitter (207) is higher than a first preset air cooling threshold, the air cooling fan (2061) is turned on; when the temperature measured by the air cooling temperature transmitter (207) is lower than a second preset air cooling threshold, the air cooling fan (2061) is turned off; and / or The oil cooling start and stop steps specifically include: when the temperature measured by the oil temperature transmitter (213) is higher than a first preset oil cooling threshold, the oil cooling fan (2091) is turned on; when the temperature measured by the oil temperature transmitter (213) is lower than a second preset oil cooling threshold, the oil cooling fan (2091) is turned off.

4. The one-island type full-quantity recovery method for oilfield associated gas according to claim 1, characterized in that: Also includes: The steps of chain alarm include: When the pressure measured by the outlet pressure transmitter (208) is higher than a third preset pressure threshold, an interlock alarm is triggered and the gas compressor (203) is shut down; and / or When the liquid level measured by the liquid level transmitter (210) is lower than a first preset liquid level threshold, an interlock alarm is triggered and the gas compressor (203) is shut down; and / or When the oxygen content measured by the oxygen content detector (103) is higher than a first preset oxygen content threshold, the air intake emergency discharge valve (401) is opened to discharge air urgently, and an alarm is triggered and the gas compressor (203) is shut down; and / or When the pressure value measured by the intake pressure transmitter (106) exceeds a first preset pressure threshold, the intake emergency exhaust valve (401) is opened / activated to perform emergency exhaust, and an alarm is triggered and the gas compressor (203) is shut down; and / or When the flow rate measured by the air intake flow meter (101) exceeds the rated flow rate of the whole equipment, the air intake emergency discharge valve (401) is opened / activated to discharge air urgently, and at the same time, an interlock alarm is triggered and the gas compressor (203) is shut down.

5. The one-island type full-quantity recovery method for oilfield associated gas according to claim 1, characterized in that: In the step of pressurized condensation: The associated gas dry gas outputted from the oil-gas separator (304) enters the air-cooled recovery heat exchanger (301) for cold recovery, and then passes through the first intermediate check valve (503) and the inlet check valve (502) in sequence to enter the associated gas generator (501) for power generation; The cold source of the water removal heat exchanger A (3021) is provided by the first refrigeration compressor (3111); the cold source of the pressurized condensing oil separation heat exchanger A (3031) is provided by the second refrigeration compressor (3121); the cold source of the water removal heat exchanger B (3022) is provided by the third refrigeration compressor (3112); the cold source of the pressurized condensing oil separation heat exchanger B (3032) is provided by the fourth refrigeration compressor (3122); Among them, the power supply of the first refrigeration compressor (3111), the second refrigeration compressor (3121), the third refrigeration compressor (3112), the fourth refrigeration compressor (3122), the gas compressor (203), the air-cooling fan (2061), and the oil-cooling fan (2091), and the control power supply required by each valve and each instrument are all provided by the associated gas generator (501), thereby realizing the island operation of the entire system.

6. The one-island type full-quantity recovery method for oilfield associated gas according to claim 1, characterized in that: in, When the oilfield associated gas is first introduced, it first passes through the intake flow meter (101), the intake flame arrester (102), the outlet emergency exhaust valve (403), the second intermediate check valve (504), and the inlet check valve (502), and then enters the associated gas generator (501) to generate electricity, thereby providing power supply for the entire system; Among them, when the associated gas generator (501) obtains gas to generate electricity, the refrigeration compressor of the A side branch or the B side branch can be started to establish the cold field temperature of the water removal heat exchanger and the pressurized condensation oil separation heat exchanger of the corresponding branch. After the cold field temperature is established, the outlet gas emergency exhaust valve (403) is closed, the gas compressor (203) is started, and the air intake shut-off valve and the air outlet shut-off valve of the corresponding branch are opened. The system operation process of oilfield associated gas intake, compression and transportation, pressurization and condensation and dry gas power generation is carried out.

7. The one-island type full-quantity recovery method for oilfield associated gas according to claim 5, characterized in that: The first preset oxygen content threshold is adjustable and is set to 5%; and / or The first preset pressure threshold is adjustable and is set to 2500 Pa; and / or The rated flow rate of the whole equipment is adjustable and is set to 3000m 3 / d; and / or The set pressure of the oil safety valve (404) is set to 0.96 MPa; and / or The third preset pressure threshold is adjustable and is set to 0.88 MPa; and / or The first preset liquid level threshold is adjustable and is set to 50 mm; and / or The first preset air cooling threshold is adjustable and is set to 40°C; and / or The second preset air cooling threshold is adjustable and is set to 25°C; and / or The first preset oil cooling threshold is adjustable and is set to 60°C; and / or The second preset oil cooling threshold is adjustable and is set to 50°C.

8. The one-island type full-quantity recovery method for oilfield associated gas according to claim 3, characterized in that: The A-side branch and the B-side branch are switched regularly according to the set time period; When the A side branch is ventilated, the air inlet cut-off valve A (3061) and the air outlet cut-off valve A (3071) are opened; when the A side branch is not ventilated, the air inlet cut-off valve A (3061) and the air outlet cut-off valve A (3071) are closed; When the B-side branch is ventilated, the air inlet shut-off valve B (3062) and the air outlet shut-off valve B (3072) are opened; when the B-side branch is not ventilated, the air inlet shut-off valve B (3062) and the air outlet shut-off valve B (3072) are closed; Among them, the air inlet cut-off valve A (3061) and the air outlet cut-off valve A (3071) on the A side branch are opened and closed at the same time; Among them, the air inlet shut-off valve B (3062) and the air outlet shut-off valve B (3072) on the B side branch are opened and closed at the same time.

9. The one-island type full-quantity recovery method for oilfield associated gas according to claim 3, characterized in that: When the associated gas generator (501) obtains gas for the first time to generate electricity and the A side branch is selected for ventilation, the first refrigeration compressor (3111) and the second refrigeration compressor (3121) on the A side branch are started to establish the cold field temperature of the water removal heat exchanger A (3021) and the pressurized condensation oil separation heat exchanger A (3031); after the first cold field temperature is established, the outlet gas emergency exhaust valve (403) is closed, the gas compressor (203) is started, and the intake shut-off valve A (3061) and the outlet shut-off valve A (3071) are opened, and the oilfield associated gas is subjected to the conventional system operation process of intake, compression and transportation, pressurization and condensation, and dry gas power generation; When the associated gas generator (501) obtains gas for the first time to generate electricity and the B side branch is selected for ventilation, the third refrigeration compressor (3112) and the fourth refrigeration compressor (3122) on the B side branch are started to establish the cold field temperature of the water removal heat exchanger B (3022) and the pressurized condensation oil separation heat exchanger B (3032); after the first cold field temperature is established, the outlet gas emergency exhaust valve (403) is closed, the gas compressor (203) is started, and the intake shut-off valve B (3062) and the outlet shut-off valve B (3072) are opened, and the oil field associated gas is subjected to the conventional system operation process of intake, compression and transportation, pressurization and condensation, and dry gas power generation.

10. The one-island type full-quantity recovery method for oilfield associated gas according to claim 3, characterized in that: When the associated gas generator (501) is continuously generating gas, for example, switching between the A-side branch and the B-side branch is performed, before the switching, the refrigeration compressor of the other branch is first started to establish the cold field temperature of the dehydration heat exchanger and the pressurized condensation oil separation heat exchanger of the corresponding branch. After the cold field temperature is established, the air inlet shut-off valve and the air outlet shut-off valve of the original ventilation branch are closed, and the air inlet shut-off valve and the air outlet shut-off valve of the branch to be ventilated are opened / opened, so as to realize seamless and flexible switching of the bilateral branches, and realize continuous operation of the oilfield associated gas for air intake, compression and transportation, pressurization and condensation, and dry gas power generation; the original ventilation branch that is switched is switched from the refrigeration mode to the defrosting mode, and the branch is shut down after the defrosting is completed, until the refrigeration compressor of the branch is started again before the next branch switching to enter the refrigeration mode, so as to establish the cold field temperature of the dehydration heat exchanger and the pressurized condensation oil separation heat exchanger of the branch; and the alternating cycle operation is carried out in this way; When the associated gas generator (501) is continuously generating electricity, if switching is performed from the A-side branch to the B-side branch, before the switching, the third refrigeration compressor (3112) and the fourth refrigeration compressor (3122) on the B-side branch are first started to establish the cold field temperature of the dewatering heat exchanger B (3022) and the pressurized condensing oil separation heat exchanger B (3032). After the cold field temperature is established, the air inlet shut-off valve B (3062) and the air outlet shut-off valve B (3072) of the B-side branch are opened / opened, and the air inlet shut-off valve A (3061) and the air outlet shut-off valve A (3071) of the A-side branch are closed, so as to realize the switching from the A-side branch to the B-side branch. The seamless switching of the A-side branch realizes the continuous operation of the associated gas intake, compression and transportation, pressurization and condensation, and dry gas power generation in the oil field; the switched A-side branch is switched from the cooling mode to the defrosting mode. After the defrosting is completed, the first refrigeration compressor (3111) and the second refrigeration compressor (3121) of the A-side branch are shut down until the next branch switching, when the first refrigeration compressor (3111) and the second refrigeration compressor (3121) of the A-side branch are restarted to enter the cooling mode, and the cold field temperature of the A-side branch water removal heat exchanger A (3021) and the pressurization and condensation oil separation heat exchanger A (3031) is established; the operation is carried out in an alternating cycle; When the associated gas generator (501) is continuously generating electricity, if switching is performed from the B-side branch to the A-side branch, before the switching, the first refrigeration compressor (3111) and the second refrigeration compressor (3121) on the A-side branch are started first to establish the cold field temperature of the water removal heat exchanger A (3021) and the pressurized condensation oil separation heat exchanger A (3031). After the cold field temperature is established, the air inlet shut-off valve A (3061) and the air outlet shut-off valve A (3071) of the A-side branch are opened / opened, and the air inlet shut-off valve B (3062) and the air outlet shut-off valve B (3072) of the B-side branch are closed, so as to realize the switching of the B-side branch to the A-side branch. Seamless switching is achieved, thereby realizing continuous operation of oilfield associated gas intake, compression and transportation, pressurized condensation and dry gas power generation; the switched B side branch is switched from refrigeration mode to defrost mode, and after defrosting, the third refrigeration compressor (3112) and the fourth refrigeration compressor (3122) of the B side branch are shut down until the next branch switching, when the third refrigeration compressor (3112) and the fourth refrigeration compressor (3122) of the B side branch are restarted to enter the refrigeration mode, and the cold field temperature of the B side branch dehydration heat exchanger B (3022) and the pressurized condensation oil separation heat exchanger B (3032) is established; and the cycle operation is alternating in this way.

11. A Dokdo-type fully quantitative recovery method for oilfield associated gas, characterized in that: The system is a one-island type fully quantitative recovery system for oilfield associated gas, the system comprising an air intake unit (100), a compression and transportation unit (200), a pressurized condensation separation unit (300), an emergency air discharge unit (400) and a dry gas power generation unit (500); the method comprises the following steps: The air intake step specifically comprises: in the air intake unit (100), the oilfield associated gas drawn in enters the compression and delivery unit (200) through the air intake flow meter (101) and the air intake flame arrester (102); The step of compression and transportation specifically comprises: the gas entering the compression and transportation unit (200) through the air intake unit (100) first passes through the air intake filter (201) for high-efficiency filtration and separation, then enters the moving equipment gas compressor (203) through the loading valve (202) for room temperature compression and pressurization to a first compression and pressurization threshold, the pressurized gas enters the oil-gas separator (204) for gas and oil separation, the separated gas is discharged from the first gas outlet of the oil-gas separator (204), and is transported to the air-cooled heat exchanger (2062) through the oil-gas one-way valve (205) for air-cooled heat exchange and cooling to room temperature, and then output to the pressurized condensing unit (300); The step of pressurized condensation specifically comprises: the pressurized normal temperature gas after being pressurized by the compression and delivery unit (200) enters the pressurized condensation unit (300), and first enters the air-cooled recovery heat exchanger (301) for gas-to-gas heat exchange and primary cooling; When the A side branch is ventilated, the gas after the primary cooling can enter the water removal heat exchanger A (3021) through the air inlet shut-off valve A (3061) for secondary cooling to separate free water or part of heavy hydrocarbons, and then enter the pressurized condensation oil separation heat exchanger A (3031) for tertiary cooling to separate supersaturated water or part of light hydrocarbons, and then enter the oil-gas separator (304) through the air outlet shut-off valve A (3071); When the B-side branch is ventilated, the gas after the primary cooling can enter the water removal heat exchanger B (3022) through the air inlet shut-off valve B (3062) for secondary cooling to separate free water or part of heavy hydrocarbons, and then enter the pressurized condensation oil separation heat exchanger B (3032) for tertiary cooling to separate supersaturated water or part of light hydrocarbons, and then enter the oil-gas separator (304) through the air outlet shut-off valve B (3072); The step of emergency air discharge comprises: when the oxygen content measured by the oxygen content detector (103) in the air intake unit (100) is higher than a first preset oxygen content threshold, opening the air intake emergency discharge valve (401) in the emergency air discharge unit (400) to discharge air urgently; when the oxygen content measured by the oxygen content detector (103) is lower than the first preset oxygen content threshold, closing the air intake emergency discharge valve (401); When the pressure value measured by the intake pressure transmitter (106) exceeds a first preset pressure threshold, the intake emergency exhaust valve (401) is opened / activated to perform emergency exhaust; when the pressure value measured by the intake pressure transmitter (106) is less than the first preset pressure threshold, the intake emergency exhaust valve (401) is closed; When the flow rate measured by the air intake flow meter (101) exceeds the rated flow rate of the whole equipment, the air intake emergency exhaust valve (401) is opened / activated to perform emergency exhaust; when the flow rate measured by the air intake flow meter (101) is lower than the rated flow rate of the whole equipment, the air intake emergency exhaust valve (401) is closed; When the pressure of the oil safety valve (404) in the emergency air discharge unit (400) exceeds its set pressure, the oil safety valve (404) is opened to discharge air urgently; The step of dry gas power generation specifically comprises: the associated gas dry gas outputted from the oil-gas separator (304) enters the air-cooled recovery heat exchanger (301) for cold recovery, and then enters the dry gas power generation unit (500) and sequentially passes through the first intermediate check valve (503) and the inlet check valve (502) to enter the associated gas generator (501) for power generation; When the oilfield associated gas is first introduced, the oilfield associated gas is sequentially passed through the air inlet flow meter (101), the air inlet flame arrester (102), the air outlet emergency exhaust valve (403), the second intermediate check valve (504), and the inlet check valve (502), and then input into the associated gas generator (501) to generate electricity; Part of the associated dry gas can be output to external equipment via the self-operated regulating valve (507), the outlet check valve (508) and the outlet flame arrester (506) in sequence.

12. The one-island type full-quantity recovery method for oilfield associated gas according to claim 11, characterized in that: In the step of compressing and conveying: the temperature of the gas after being pressurized by the gas compressor (203) is between 60 and 80°C, and then it is cooled to a normal temperature of about 45°C by the air-cooled heat exchanger (2062); and / or The first compression pressure threshold is set to 0.8 MPa; and / or The oil and gas one-way valve (205) is a mechanical one, and its pressure setting value is 0.4 MPa; and / or The pre-valve pressure threshold of the self-operated regulating valve (507) is adjustable and is set to 0.7 MPa; and / or The pressure threshold before the automatic regulating valve (505) is adjustable and is set to 0.7 MPa; and / or Wherein, the cold field temperature of the water removal heat exchanger A (3021) is +5°C; and / or Wherein, the cold field temperature of the pressurized condensing oil separation heat exchanger A (3031) is -35°C; and / or Wherein, the cold field temperature of the water removal heat exchanger B (3022) is +5°C; and / or Wherein, the cold field temperature of the pressurized condensing oil separation heat exchanger B (3032) is -35°C; and / or Wherein, the cold field temperature of the air-cooled recovery heat exchanger (301) is 15°C; and / or Among them, the air outlet emergency exhaust valve (403) is a normally open valve.

13. The one-island type full-quantity recovery method for oilfield associated gas according to any one of claims 11 to 12, characterized in that: The system is used for a single island type fully quantitative recovery system of associated gas in an oil field, comprising an air intake unit (100), a compression and delivery unit (200) connected to a gas phase pipeline of the air intake unit (100), a pressurization and condensation unit (300) connected to a gas phase pipeline of the compression and delivery unit (200), a dry gas power generation unit (500) connected to a gas phase pipeline of the pressurization and condensation unit (300), and an emergency air discharge unit (400) connected to the gas phase pipelines of the air intake unit (100), the compression and delivery unit (200), and the dry gas power generation unit (500); The air intake unit (100) comprises an air intake flow meter (101) and an air intake flame arrester (102) connected to the air outlet end of the air intake flow meter (101); The gas phase pipeline of the compression and delivery unit (200) comprises an air intake filter (201), a loading valve (202) connected to the outlet end of the air intake filter (201), a gas compressor (203) connected to the outlet end of the loading valve (202), an oil-gas separator (204) connected to the outlet end of the gas compressor (203), an oil-gas check valve (205) connected to the first air outlet end of the oil-gas separator (204), a reflux cut-off valve (214) connected to the second air outlet end of the oil-gas separator (204), and an air-cooled heat exchanger (2062) connected to the outlet end of the oil-gas check valve (205); The oil phase pipeline of the compression and delivery unit (200) comprises an oil-gas separator (204), an oil-cooling heat exchanger (2092) connected to the oil outlet end of the oil-gas separator (204), an oil filter (211) connected to the outlet end of the oil-cooling heat exchanger (2092), and an oil cut-off valve (212) connected to the outlet end of the oil filter (211); the other end of the oil cut-off valve (212) is connected to the oil return port of the gas compressor (203).

14. The one-island type full-quantity recovery method for oilfield associated gas according to claim 13, characterized in that: The pressurized condensing unit (300) comprises an air-cooled recovery heat exchanger (301), and an air intake cut-off valve A (3061), a water removal heat exchanger A (3021), a pressurized condensing oil separation heat exchanger A (3031), and an air outlet cut-off valve A (3071) located on the A side branch, and an air intake cut-off valve B (3062), a water removal heat exchanger B (3022), a pressurized condensing oil separation heat exchanger B (3032), and an air outlet cut-off valve B (3072) located on the B side branch; The emergency discharge air-discharging unit (400) comprises an air intake emergency discharge valve (401), an oil separation safety valve (404) and an air outlet emergency discharge valve (403); The dry gas power generation unit (500) comprises a first intermediate one-way valve (503), a second intermediate one-way valve (504), an associated gas generator (501) and a self-operated regulating valve (507); The inlet end of the air intake emergency exhaust valve (401) is connected to the outlet of the air intake flame arrester (102) in the air intake unit (100); The inlet end of the oil safety valve (404) is connected to the third outlet end of the oil-gas separator (204); The inlet end of the air outlet emergency exhaust valve (403) is connected to the outlet of the air intake flame arrester (102) in the air intake unit (100); The inlet end of the second intermediate one-way valve (504) is connected to the outlet end of the air outlet emergency exhaust valve (403); The inlet end of the first intermediate non-return valve (503) is connected to the cold side air path outlet of the air-cooled recovery heat exchanger (301).

15. The one-island type full-quantity recovery method for oilfield associated gas according to claim 11, characterized in that: The backflow cut-off valve (214) is interlocked with the gas compressor (203); and / or The air-cooling temperature transmitter (207) is interlocked with the air-cooling fan (2061); and / or The oil temperature transmitter (213) is interlocked with the oil cooling fan (2091); and / or The outlet pressure transmitter (208) and the liquid level transmitter (210) are both interlocked with the gas compressor (203); and / or The oxygen content detector (103), the intake pressure transmitter (106) and the intake flow meter (101) are all interlocked with the gas compressor (203); and / or The oxygen content detector (103), the intake pressure transmitter (106) and the intake flow meter (101) are all interlocked with the intake emergency exhaust valve (401) for control.

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