A multi-stage adsorption and condensation combined oil and gas recovery system

Abstract

This utility model discloses a multi-stage adsorption and condensation combined oil and gas recovery system, belonging to the field of oil and gas recovery technology. It includes a pretreatment module, a multi-stage condensation module, an adsorption module, an oil-water separation module, a vacuum regeneration module, and a control system. The pretreatment module is connected sequentially via pipelines to a flame arrester, a vacuum pump, a compressor, and a shell-and-tube heat exchanger. The compressor outlet is connected to the multi-stage condensation module and the adsorption module via a first three-way valve. The multi-stage condensation module consists of three condensers connected in series, with the condensation temperature decreasing progressively in each stage. The outlet of the final condenser is connected to the inlet of the adsorption module via a flame arrester. The adsorption module includes two adsorption tanks, A and B, connected in parallel. Each tank is filled with an activated carbon adsorption layer and a ceramic fiber filter layer. The bottom of the adsorption tank is connected to the vacuum regeneration module via a second three-way valve. By gradually reducing the gas volume through the multi-stage condensation module, the refrigeration load of subsequent stages is reduced, improving the adsorption efficiency of the subsequent adsorption modules.

Description

Technical Field

[0001] This utility model belongs to the field of oil and gas recovery technology, specifically relating to an oil and gas recovery system that combines multi-stage adsorption and condensation. Background Technology

[0002] In traditional oil and gas recovery technologies, condensation and adsorption methods are often used alone, which has the following drawbacks:

[0003] 1. The single condensation method requires deep condensation to below -100℃ to process low-boiling-point hydrocarbons, which consumes a lot of energy and has high equipment costs;

[0004] 2. When using a single adsorption method to treat high-concentration oil and gas, the adsorbent saturates quickly, requiring frequent regeneration, and the quality of the recovered oil is not high.

[0005] To overcome the above problems, oil and gas recovery systems that combine adsorption and condensation have emerged. However, the process arrangement of adsorption and condensation in existing technologies is not optimized enough, resulting in the need to improve the overall system efficiency. Some systems lack adaptability to oil and gas components during oil and gas processing, and the equipment structure is complex with low automation, making it difficult to achieve precise control and efficient operation. Summary of the Invention

[0006] To address the aforementioned problems, this utility model discloses an oil and gas recovery system that combines multi-stage adsorption and condensation. Through multi-stage condensation modules, high-boiling-point components, medium-boiling-point components, and low-boiling-point components in the oil and gas are liquefied sequentially, gradually reducing the gas volume and lowering the refrigeration load in subsequent stages. After condensation, the oil and gas load entering the adsorption module is significantly reduced, extending the regeneration cycle of the activated carbon adsorption layer and improving the adsorption efficiency of subsequent adsorption modules.

[0007] To achieve the above objectives, the specific technical solution of this application is as follows:

[0008] A multi-stage adsorption and condensation combined oil and gas recovery system includes a pretreatment module, a multi-stage condensation module, an adsorption module, an oil-water separation module, a vacuum regeneration module, and a control system.

[0009] The pretreatment module is connected in sequence to a flame arrester, an air extraction pump, a compressor, and a shell-and-tube heat exchanger via pipelines. The outlet of the shell-and-tube heat exchanger is connected to a multi-stage condensation module and an adsorption module via a first three-way valve.

[0010] The multi-stage condensation module consists of three condensers connected in series. The condensation temperature of the three condensers decreases step by step. The outlet of the last condenser is connected to the inlet of the adsorption module via a flame arrester.

[0011] The adsorption module includes adsorption tank A and adsorption tank B connected in parallel. The tanks are filled with activated carbon adsorption layers and ceramic fiber filter layers. The bottom of the adsorption tank is connected to the vacuum regeneration module through a second three-way valve.

[0012] The oil-water separation module is a horizontal separator, including an aqueous phase zone, an oil phase zone, and a buffer zone. The top is connected to the compressor inlet via a gas phase pipeline, and the bottom is connected to the oil storage tank via an explosion-proof oil pump.

[0013] The vacuum regeneration module includes a dry vortex vacuum pump, an air-cooled condenser, and a return-to-tank pipeline. The vacuum pump is connected to the bottom of the adsorption tank, and its outlet is connected to the compressor inlet of the pretreatment module via the air-cooled condenser and the return-to-tank pipeline.

[0014] Based on the above technical features, preferably, the preprocessing module includes a temperature sensor and a humidity sensor.

[0015] Based on the above technical features, preferably, a liquid level sensor and a pneumatic regulating valve are installed at the outlet of each stage of the condenser.

[0016] Based on the above technical features, the control system further includes a PLC controller, a frequency converter, and a touch screen. The PLC controller is connected to a temperature sensor, a humidity sensor, a liquid level sensor, and a pneumatic regulating valve via signal lines. The frequency converter controls the speed of the compressor and the vacuum pump.

[0017] Based on the above technical features, preferably, the shell-and-tube heat exchanger of the pretreatment module adopts a counter-flow design, with cooling water flowing through the shell side and oil and gas flowing through the tube side, the heat exchange area ratio being 1:1.5-3.0, and the outlet oil and gas temperature dropping to 10-25℃.

[0018] Based on the above technical features, preferably, the first stage condensing temperature of the three-stage condenser is set to 3-8℃, the second stage to -40-60℃, and the third stage to -70-100℃.

[0019] Based on the above technical features, preferably, the third-stage condenser of the multi-stage condensing module adopts a finned evaporator, and the refrigerant is R507A.

[0020] Based on the above technical features, preferably, a differential pressure sensor is installed on the top of the adsorption tank A and the adsorption tank B, the activated carbon adsorption layer has a thickness of 800-1200mm, the ceramic fiber filter layer is located above the adsorption layer with a thickness of 200-400mm, and the inner wall of the adsorption tank is coated with a polytetrafluoroethylene anti-corrosion coating.

[0021] Based on the above technical features, preferably, a Venturi injector is installed on the return capsule pipeline of the vacuum regeneration module, the injection medium is nitrogen, the injection pressure is 0.3-0.5 MPa, and the return capsule gas is cooled to -10~5℃ by an air-cooled condenser before entering the compressor.

[0022] Compared with the prior art, the beneficial effects of this application include at least one of the following:

[0023] This application uses a multi-stage condensation module to sequentially liquefy high-boiling-point components, medium-boiling-point components and low-boiling-point components in oil and gas, gradually reducing the gas volume and lowering the refrigeration load in subsequent stages. After condensation, the oil and gas load entering the adsorption module is greatly reduced, the regeneration cycle of the activated carbon adsorption layer is extended and the adsorption efficiency of subsequent adsorption modules is improved.

[0024] The redundant design of the first three-way valve allows it to bypass the condensation module and directly enter the adsorption module for processing when the initial concentration of oil and gas is low, thus avoiding energy waste from low-temperature condensation and saving energy.

[0025] The ceramic fiber filter layer prevents activated carbon from pulverizing, the polytetrafluoroethylene coating resists corrosion, and the adsorption module lifespan is extended.

[0026] The parallel connection of dual adsorption tanks and Venturi injectors enhances the flow of desorbed gas, and the polytetrafluoroethylene anti-corrosion coating extends the tank life.

[0027] By dynamically adjusting the condensing temperature at each stage using a PLC, it can adapt to changes in ambient temperature and maintain stable condensing efficiency. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of an oil and gas recovery system combining multi-stage adsorption and condensation according to the present invention.

[0029] List of identifiers in attached diagrams:

[0030] Pretreatment module; 101, flame arrester; 102, temperature sensor; 103, humidity sensor; 104, air extraction pump; 105, compressor; 106, shell and tube heat exchanger; 107, first three-way valve;

[0031] Multi-stage condensation module; 201, liquid level sensor; 202, pneumatic control valve;

[0032] Adsorption module; 301, Adsorption tank A; 302, Adsorption tank B; 303, Activated carbon adsorption layer; 304, Ceramic fiber filter layer; 305, Second three-way valve;

[0033] 4. Oil-water separation module; 401. Aqueous phase zone; 402. Oil phase zone; 403. Buffer zone; 404. Explosion-proof oil pump; 405. Oil storage tank;

[0034] 5. Vacuum regeneration module; 501. Dry vortex vacuum pump; 502. Air-cooled condenser; 503. Return capsule pipeline;

[0035] 6. Control system. Detailed Implementation

[0036] The present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are for illustrative purposes only and are not intended to limit the scope of the invention.

[0037] It should be noted that the terms "upper," "lower," "left," "right," "front," and "rear" used in the following description refer to the directions shown in the accompanying drawings, while the terms "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively. Furthermore, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0038] like Figure 1 As shown, an oil and gas recovery system combining multi-stage adsorption and condensation includes a pretreatment module 1, a multi-stage condensation module 2, an adsorption module 3, an oil-water separation module 4, a vacuum regeneration module 5, and a control system 6.

[0039] The pretreatment module 1 is connected in sequence to a flame arrester 101, a temperature sensor 102, a humidity sensor 103, a vacuum pump 104, a compressor 105, and a shell-and-tube heat exchanger 106 via pipelines. The outlet of the shell-and-tube heat exchanger 106 is connected to a multi-stage condensation module 2 and an adsorption module 3 via a first three-way valve 107.

[0040] The multi-stage condensing module 2 consists of three condensers connected in series. Each condenser outlet is equipped with a liquid level sensor 201 and a pneumatic regulating valve 202. The condensing temperature of the three condensers decreases progressively. The outlet of the final condenser is connected to the inlet of the adsorption module 3 via a flame arrester. Preferably, the condensing temperature of the first stage of the three condensers is set to 3-8℃, the second stage to -40-60℃, and the third stage to -70-100℃. The third stage condenser of the multi-stage condensing module 2 is a finned evaporator, and the refrigerant is R507A.

[0041] The adsorption module 3 includes adsorption tanks A301 and B302 connected in parallel. The tanks are filled with activated carbon adsorption layer 303 and ceramic fiber filter layer 304. The bottom of the adsorption tank is connected to the vacuum regeneration module 5 through a second three-way valve 305.

[0042] The oil-water separation module 4 is a horizontal separator, including an aqueous phase zone 401, an oil phase zone 402 and a buffer zone 403. The top is connected to the compressor 105 inlet through a gas phase pipeline, and the bottom is connected to the oil storage tank 405 through an explosion-proof oil pump 404.

[0043] The vacuum regeneration module 5 includes a dry vortex vacuum pump 501, an air-cooled condenser 502, and a return chamber pipe 503. The vacuum pump 501 is connected to the bottom of the adsorption tank, and its outlet is connected to the inlet of the compressor 105 of the pretreatment module 1 via the air-cooled condenser 502 and the return chamber pipe 503.

[0044] The control system 6 includes a PLC controller, a frequency converter, and a touch screen. The PLC controller is connected to the temperature sensor 102, humidity sensor 103, liquid level sensor 201, and pneumatic regulating valve 202 via signal lines. The frequency converter controls the speed of the compressor 105 and the vacuum pump 501.

[0045] The shell-and-tube heat exchanger 106 of the pretreatment module 1 adopts a counter-flow design, with cooling water flowing through the shell side and oil and gas flowing through the tube side. The heat exchange area ratio is 1:1.5-3.0, and the outlet oil and gas temperature drops to 10-25℃.

[0046] Differential pressure sensors 306 are installed on the top of adsorption tanks A301 and B302. The activated carbon adsorption layer 303 has a thickness of 800-1200mm. The ceramic fiber filter layer 304 is located above the adsorption layer and has a thickness of 200-400mm. The inner wall of the adsorption tank is coated with a polytetrafluoroethylene anti-corrosion coating.

[0047] The vacuum regeneration module 5 is equipped with a venturi injector 505 on the return capsule pipeline 503. The injection medium is nitrogen gas, and the injection pressure is 0.3-0.5MPa. The return capsule gas is cooled to -10~5℃ by the air-cooled condenser 502 and then enters the compressor 105.

[0048] Working principle:

[0049] Oil and gas treatment stage: After being cooled and pressurized by the pretreatment module, the oil and gas enter the multi-stage condensation module 2 through the first three-way valve 107, where it is condensed and liquefied step by step; the uncondensed low-temperature and low-concentration oil and gas enters the adsorption module, where residual hydrocarbons are adsorbed by activated carbon, and the purified gas is discharged in compliance with standards.

[0050] Adsorbent regeneration stage: When the differential pressure sensor 306 detects that the resistance of the adsorption tank exceeds the limit, the PLC controls the three-way valve 305 to switch to the regeneration mode; the vacuum pump 501 draws a vacuum for desorption, and the desorbed gas is returned to the system after condensation and recovery, and the activated carbon restores its adsorption capacity.

[0051] Oil-water separation stage: Condensate enters horizontal separator 4, oil phase is transported to oil storage tank 406 by explosion-proof oil pump 405, water phase is discharged periodically, and gas phase is returned to compressor 105 for recycling.

[0052] In summary, this application solves the above problems by designing a multi-stage condensation temperature gradient, implementing a dynamic switching mechanism for adsorption-regeneration, and optimizing the intelligent control system, thereby achieving a synergy between high recovery rate and low energy consumption.

[0053] It should be noted that the accompanying drawings merely illustrate the technical concept of the present invention and should not be used to limit the scope of protection of the present invention. For those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and all such improvements and modifications fall within the scope of protection of the claims of the present invention.

Claims

1. An oil and gas recovery system combining multi-stage adsorption and condensation, characterized in that: It includes a pretreatment module (1), a multi-stage condensation module (2), an adsorption module (3), an oil-water separation module (4), a vacuum regeneration module (5), and a control system (6); The pretreatment module (1) is connected in sequence to a flame arrester (101), a vacuum pump (104), a compressor (105), and a shell-and-tube heat exchanger (106) via pipes. The outlet of the shell-and-tube heat exchanger (106) is connected to a multi-stage condensation module (2) and an adsorption module (3) via a first three-way valve (107). The multi-stage condensation module (2) is composed of three condensers connected in series. The condensation temperature of the three condensers decreases step by step. The outlet of the last condenser is connected to the inlet of the adsorption module (3) via a flame arrester. The adsorption module (3) includes adsorption tank A (301) and adsorption tank B (302) connected in parallel. The tanks are filled with activated carbon adsorption layer (303) and ceramic fiber filter layer (304). The bottom of the adsorption tank is connected to the vacuum regeneration module (5) through a second three-way valve (305). The oil-water separation module (4) is a horizontal separator, including an aqueous phase zone (401), an oil phase zone (402) and a buffer zone (403). The top is connected to the compressor (105) inlet through a gas phase pipeline, and the bottom is connected to the oil storage tank (405) through an explosion-proof oil pump (404). The vacuum regeneration module (5) includes a dry vortex vacuum pump (501), an air-cooled condenser (502), and a return tank pipeline (503). The vacuum pump (501) is connected to the bottom of the adsorption tank, and its outlet is connected to the inlet of the compressor (105) of the pretreatment module (1) via the air-cooled condenser (502) and the return tank pipeline (503).

2. The oil and gas recovery system combining multi-stage adsorption and condensation according to claim 1, characterized in that: The preprocessing module (1) is equipped with a temperature sensor (102) and a humidity sensor (103).

3. The oil and gas recovery system combining multi-stage adsorption and condensation according to claim 2, characterized in that: Each stage of the condenser outlet is equipped with a liquid level sensor (201) and a pneumatic regulating valve (202).

4. The oil and gas recovery system combining multi-stage adsorption and condensation according to claim 3, characterized in that: The control system (6) includes a PLC controller, a frequency converter and a touch screen. The PLC controller is connected to a temperature sensor (102), a humidity sensor (103), a liquid level sensor (201) and a pneumatic regulating valve (202) via signal lines. The frequency converter controls the speed of the compressor (105) and the vacuum pump (501).

5. The oil and gas recovery system combining multi-stage adsorption and condensation according to claim 1, characterized in that: The shell-and-tube heat exchanger (106) of the pretreatment module (1) adopts a counter-flow design, with cooling water flowing through the shell side and oil and gas flowing through the tube side. The heat exchange area ratio is 1:1.5-3.0, and the outlet oil and gas temperature drops to 10-25℃.

6. The oil and gas recovery system combining multi-stage adsorption and condensation according to claim 1, characterized in that: The first stage of the three-stage condenser is set to a condensation temperature of 3-8℃, the second stage to -40-60℃, and the third stage to -70-100℃.

7. The oil and gas recovery system combining multi-stage adsorption and condensation according to claim 1, characterized in that: The third-stage condenser of the multi-stage condensing module (2) is a finned evaporator, and the refrigerant is R507A.

8. The oil and gas recovery system combining multi-stage adsorption and condensation according to claim 1, characterized in that: The adsorption tanks A (301) and B (302) are equipped with differential pressure sensors (306) on top. The activated carbon adsorption layer (303) has a thickness of 800-1200 mm. The ceramic fiber filter layer (304) is located above the adsorption layer and has a thickness of 200-400 mm. The inner wall of the adsorption tank is coated with a polytetrafluoroethylene anti-corrosion coating.

9. The oil and gas recovery system combining multi-stage adsorption and condensation according to claim 1, characterized in that: The vacuum regeneration module (5) has a Venturi ejector (505) installed on the return capsule pipeline (503). The return capsule gas is cooled to -10~5℃ by the air-cooled condenser (502) and then enters the compressor (105).

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