Low-temperature oil gas recovery device

Abstract

The utility model discloses a low-temperature oil gas recovery device. The recovery device comprises a first-stage absorption tower in which oil gas is contacted with a first-stage absorbent to remove most of water and heavy hydrocarbon; primary absorption tail gas is in contact with a secondary absorbent in the secondary absorption tower, part of C3 and above components are condensed and absorbed, and residual water is frozen into ice particles; second-stage absorption tail gas is in contact with a second-stage absorbent in the third-stage absorption tower, and light hydrocarbon is further removed; the filter is used for filtering the ice-containing absorption liquid, obtained ice particles enter the first-stage absorption tower, and obtained filtrate is used as a second-stage absorbent; the primary circulating pump is used for circularly spraying the primary absorbent; and the second-stage circulating pump is used for circulating the second-stage absorption liquid to the filter so as to realize circulating spraying of the second-stage absorbent after deicing. The low-temperature oil gas recovery device has the advantages of being stable and reliable in process, simple in equipment, safe, energy-saving and the like.

Description

Technical Field

[0001] This utility model belongs to the field of environmental protection and energy conservation technology, and relates to a low-temperature oil and gas recovery and treatment device, specifically a low-temperature oil and gas recovery and treatment device for tank farms. Background Technology

[0002] During the storage and cleaning processes of oil products in tank farms, a significant amount of oil vapors and volatile organic compounds (VOCs) are released. Statistics show that approximately 0.5% of light oil products are lost annually due to these releases. This results in a substantial waste of oil vapors and VOCs, reducing the economic benefits for enterprises, and also causes serious environmental pollution. Furthermore, because oil vapors and air easily form explosive mixtures (with a lower explosive limit generally between 1% and 6%), the release of oil vapors can cause the concentration of oil vapors around the affected facilities to easily reach explosive limits. Oil vapors accumulating on the ground pose a significant safety hazard to enterprises and consumers, endangering safe production and directly impacting the health of operators and those in the surrounding environment. Therefore, the recovery and treatment of released oil vapors is essential.

[0003] There are three traditional methods for oil and gas recovery and treatment: one is to use it directly as fuel; the second is to return the oil and gas to the oil tank gas-liquid balance system to increase the partial pressure of oil and gas and reduce the loss of oil evaporation; the third is to use recovery devices and technologies, such as condensation, absorption, adsorption and their combination processes.

[0004] Patent CN202246576 U discloses a cryogenic condensation absorption and recovery device for oil and gas, including a refrigeration unit, a lean absorbent delivery pump, a venturi ejector, an oil and gas condensation absorption mixture separator, an oil and gas precooler heat exchanger, and a precooler oil and gas gas-liquid separator. Oil and gas are introduced into the venturi ejector and mixed with the cryogenic absorbent, and the oil and gas components are separated by the cryogenic absorbent through condensation and cooling. However, at the same time, the moisture in the oil and gas will be condensed and frozen by the sub-zero absorbent, and the device has an ice blockage problem during operation.

[0005] Patent CN204637927 U discloses an oil and gas recovery device. The oil and gas are first dried, then absorbed by gasoline at -30°C, with the exhaust gas used as regeneration gas for the dryer. During operation, the molecular sieve inside the dryer simultaneously adsorbs oil and gas components. During microwave thermal desorption, these components enter the regeneration gas, increasing the concentration of oil and gas in the exhaust gas and posing a safety risk of overheating the adsorbent bed.

[0006] CN101342427A discloses a method for recovering oil and gas using a combined condensation-adsorption process. The oil and gas first undergo cooling-condensation to separate some of their components. Uncondensed oil and gas are recovered by adsorption-pressure swing desorption. The adsorption tail gas meets emission standards, and the desorbed oil and gas is returned to the cooling device to mix with the collected oil and gas before entering the condenser. The recommended oil and gas condensation temperature is -80℃ to 30℃, preferably -70℃ to 40℃. This method primarily relies on condensation and liquefaction to recover oil and gas components. However, the low condensation temperature leads to crystallization within the condenser, requiring periodic removal of water crystals and condensed oil. Therefore, two series of condensers need to be used interchangeably. The overall energy consumption of the device is relatively high, and the failure rate of the refrigeration equipment is also relatively high. Furthermore, crystallization also occurs in the subsequent adsorption tank, significantly reducing the lifespan of the adsorbent.

[0007] Currently, the condensation method is mainly used to recover oil and gas in the exhaust of oil loading vehicles. The condensation temperature is -35℃ and -75℃. However, the condensation method oil and gas treatment device has the following problems during operation: (1) The condensation system is severely frosted. There is ice blockage at the switching valve or pipeline of condensation and defrosting, which makes it difficult for the condensation system to operate stably; (2) The defrosting process uses hot gas defrosting, such as hot nitrogen or refrigerant hot vapor. Using hot nitrogen defrosting increases the refrigeration load of the condensing unit, thereby increasing the condensing energy consumption; using refrigerant hot vapor defrosting not only causes the refrigeration system to operate stably and increases the configuration of the refrigeration system, but also increases the operating power of the unit. Utility Model Content

[0008] To address the shortcomings of existing condensation-based oil and gas recovery devices, this invention provides a low-temperature oil and gas recovery device. This device eliminates the problem of system ice blockage and offers advantages such as stable and reliable operation, simple equipment, safety, and energy efficiency.

[0009] The cryogenic oil and gas recovery device provided by this utility model includes:

[0010] In the primary absorption tower, the oil and gas cooled by the oil and gas cooler and the oil and gas heat exchanger come into contact with the primary absorbent, and the primary absorption tail gas is obtained at the top of the tower, and the primary absorption liquid containing water and heavy hydrocarbons is obtained at the bottom of the tower.

[0011] In a two-stage absorption tower, the tail gas from the first-stage absorption is contacted with the secondary absorbent from the secondary cooler to obtain the tail gas from the second-stage absorption and the secondary absorbent containing ice particles.

[0012] In a three-stage absorption tower, the tail gas from the secondary absorption stage comes into contact with the secondary absorbent from the secondary cooler to obtain purified gas and tertiary absorbent liquid.

[0013] The filter is used to filter the ice-containing secondary absorbent obtained from the secondary absorption tower and the tertiary absorbent obtained from the tertiary absorption tower to obtain ice particles and filtrate; the obtained ice particles are then transported to the lower part of the primary absorption tower and the obtained filtrate is then transported to the inlet of the secondary cooler.

[0014] The primary circulation pump is used to circulate the absorbent from the lower storage section of the primary absorption tower through the primary cooler to the absorbent inlet at the upper part of the primary absorption tower.

[0015] The secondary circulation pump is used to transport the ice-containing absorbent obtained from the secondary absorption tower and the tertiary absorbent obtained from the tertiary absorption tower to the filter, and to transport the secondary absorbent obtained from the filter to the secondary cooler.

[0016] Furthermore, the primary absorption tower has a cylindrical structure, comprising an upper absorption section and a lower storage section. The lower end of the absorption section has a primary oil / gas inlet, the upper end has a primary absorbent inlet, and the upper part of the absorption section has an absorbent spray system. The top end of the absorption section has an exhaust port. The middle of the storage section has a primary absorbent outlet, the upper part has an ice particle inlet, and the bottom end of the storage section has a drain port.

[0017] Furthermore, the secondary absorption tower has a cylindrical structure. The lower part of the secondary absorption tower body has a secondary oil / gas inlet (i.e., the tail gas from the primary absorption stage), the upper part has a secondary absorbent inlet, and the upper part of the body has an absorbent spray system. The top end cap of the secondary absorption tower has a secondary absorption tail gas exhaust port, and the bottom end cap has a secondary absorbent liquid outlet.

[0018] Furthermore, the three-stage absorption tower has a cylindrical structure. The lower end of the tower body has a three-stage oil / gas inlet (i.e., a two-stage absorption tail gas inlet), and the upper end has a three-stage absorbent inlet (with the same composition and temperature as the two-stage absorbent). An absorbent spray system is located in the upper part of the tower body. The top end cap of the three-stage absorption tower has a purified gas exhaust port, and the bottom end cap has a three-stage absorbent liquid outlet.

[0019] Furthermore, the lower cylinder of the spray system within the primary absorption tower is equipped with packing material for absorbent distribution, enhancing gas-liquid mass and heat transfer. The spray system within the primary absorption tower is connected to its primary absorbent inlet, enabling the absorbent to be sprayed and dispersed within the tower.

[0020] Furthermore, the area below the spraying equipment in the secondary absorption tower is an empty tower, and the spraying equipment in the secondary absorption tower is connected to the inlet of its secondary absorbent, so as to achieve spraying and dispersion of the absorbent in the tower.

[0021] Furthermore, the cylinder below the spray system in the tertiary absorption tower is filled with packing material for absorbent distribution, enhancing gas-liquid mass and heat transfer. The spray system in the tertiary absorption tower is connected to its tertiary absorbent inlet, enabling the absorbent to be sprayed and dispersed within the tower.

[0022] Furthermore, the top of the primary, secondary, and tertiary absorption towers is preferably equipped with a demisting section, which is used to capture the mist droplets carried by the exhaust gas of each absorption tower.

[0023] Furthermore, the combined cryogenic oil and gas recovery device of this utility model includes an induced draft fan, which is used to introduce oil and gas into the oil and gas recovery device. The inlet of the induced draft fan is connected to the oil and gas inlet pipe, and the outlet of the induced draft fan is connected to the inlet of the oil and gas cooler.

[0024] Furthermore, the outlet of the oil-gas cooler is connected to the high-temperature oil-gas inlet of the oil-gas heat exchanger, and the high-temperature oil-gas outlet of the oil-gas heat exchanger is connected to the oil-gas inlet of the absorption section of the primary absorption tower.

[0025] Furthermore, the exhaust port of the primary absorption tail gas of the primary absorption tower is connected to the secondary oil and gas inlet of the absorption section of the secondary absorption tower through a pipeline; the outlet of the primary absorption liquid of the primary absorption tower is connected to the inlet of the primary circulation pump, the outlet of the primary circulation pump is connected to the inlet of the primary cooler; the outlet of the primary cooler is connected to the inlet of the primary absorbent of the primary absorption tower; and the drain outlet of the primary absorption tower is connected to the drainage pipeline.

[0026] Furthermore, the oil and gas inlet of the secondary absorption tower is connected to the exhaust port of the primary absorption tail gas through a pipeline; the exhaust port of the secondary absorption tower is connected to the oil and gas inlet of the tertiary cooler through a pipeline; the absorbent outlet of the secondary absorption tower is connected to the inlet of the secondary circulation pump, and the outlet of the secondary circulation pump is connected to the inlet of the filter; the slag discharge port at the bottom of the filter is connected to the ice particle inlet of the primary absorption tower, the liquid outlet of the filter is connected to the inlet of the secondary cooler, and the outlet of the secondary cooler is connected to the inlet of the secondary absorbent.

[0027] Furthermore, the tertiary oil and gas inlet of the tertiary absorption tower is connected to the exhaust port of the secondary absorption tail gas via a pipeline; the purified gas exhaust port of the tertiary absorption tower is connected to the low-temperature oil and gas inlet of the oil and gas heat exchanger via a pipeline. The low-temperature oil and gas outlet of the oil and gas heat exchanger is connected to the purified gas pipeline. The tertiary absorbent outlet of the tertiary absorption tower is connected to the inlet of the secondary circulation pump, the outlet of the secondary circulation pump is connected to the inlet of the filter, the filtered ice particles are connected to the ice particle inlet of the primary absorption tower through the filter slag outlet, the filtered filtrate is connected to the inlet of the secondary cooler through the filter liquid outlet, and the outlet of the secondary cooler is connected to the tertiary absorbent inlet of the tertiary absorption tower. The refrigerant inlet and refrigerant outlet of the tertiary absorption tower are connected to the outlet and inlet of the refrigeration unit, respectively; an oil drain port is provided at the bottom of the tertiary absorption tower, and the oil drain port is connected to the oil drain pipeline.

[0028] Furthermore, the oil-gas cooler and oil-gas heat exchanger can adopt conventional heat exchanger structures in this field.

[0029] Furthermore, the inlet of the primary circulation pump is equipped with a primary replenishment pipe, and the inlet of the secondary circulation pump is equipped with a secondary replenishment pipe.

[0030] Furthermore, a centrifugal pump is preferred for the primary circulation pump, and a slurry pump is preferred for the secondary circulation pump.

[0031] Other technologies in this novel low-temperature oil and gas recovery device, such as refrigeration technology, heat exchange technology, and gas-liquid separation technology, are well-known to those skilled in the art.

[0032] The cryogenic oil and gas recovery device of this invention is suitable for the recovery and treatment of oil and gas, especially for the recovery and treatment of oil and gas in storage tank areas.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1. In the low-temperature oil and gas recovery device of this utility model, the oil and gas to be treated can be completely removed by primary absorption, secondary absorption and tertiary absorption. The water in the oil and gas is discharged from the oil and gas recovery device by oil-water separation, water is turned into ice particles and then simply filtered. This effectively avoids the problem of ice blockage in the current condensation method oil and gas recovery device system. At the same time, this utility model does not require the defrosting process of heat exchanger, which simplifies the process flow and greatly saves system energy consumption.

[0035] 2. In this novel low-temperature oil and gas recovery device, the primary absorption tower is used to cool and separate most of the water and heavy components in the oil and gas; the secondary absorption tower is used to separate some of the C3-C5 components and the remaining water in the oil and gas; and the tertiary absorption tower is used to separate the remaining C3-C5 components in the oil and gas. The oil and gas recovery efficiency is high and the effect is good. The primary absorption tower can prevent heavy components in the oil and gas from entering the absorbent in the secondary and tertiary absorption towers, thereby increasing the cold filter point of the absorbent in the secondary and tertiary absorption towers and extending the long-term cycle of the absorbent.

[0036] 3. In this utility model of low-temperature oil and gas recovery device, the tail gas of the absorption tower is exchanged with the pressurized and cooled oil and gas through an oil and gas heat exchanger, which effectively utilizes the cold energy contained in the low-temperature absorption tail gas and saves energy consumption.

[0037] 4. The low-temperature oil and gas recovery device of this utility model has the advantages of stable and reliable process, simple equipment, safety and energy saving. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of a low-temperature oil and gas recovery method according to the present invention.

[0039] The numbers correspond to the following: 101-exhaust fan, 102-oil-gas cooler, 103-oil-gas heat exchanger, 104-primary absorption tower, 105-primary circulating pump, 106-primary cooler, 107-secondary absorption tower, 108-tertiary absorption tower, 109-secondary circulating pump, 110-filter, 111-secondary cooler.

[0040] 1- Primary oil and gas inlet, 2- Primary absorbent inlet, 3- Primary absorption tail gas exhaust port, 4- Primary absorbent liquid outlet, 5- Ice particle inlet, 6- Drain outlet, 7- Secondary oil and gas inlet, 8- Secondary absorbent inlet, 9- Secondary absorption tail gas exhaust port, 10- Secondary absorbent liquid outlet, 11- Tertiary oil and gas inlet, 12- Tertiary absorbent inlet, 13- Purified gas exhaust port, 14- Tertiary absorbent liquid outlet, 15- Liquid inlet, 16- Absorbent outlet, 17- Slag outlet. Detailed Implementation

[0041] The present invention will be further illustrated by specific embodiments below, but is not limited to the embodiments described below.

[0042] Combination Figure 1 The low-temperature oil and gas recovery device of this utility model includes: an exhaust fan 101, an oil and gas cooler 102, an oil and gas heat exchanger 103, a primary absorption tower 104, a secondary absorption tower 107, a tertiary absorption tower 108, a primary circulation pump 105, a secondary circulation pump 109, a primary cooler 106, a secondary cooler 111, a filter 110, and related connecting pipes.

[0043] The primary absorption tower 104 contains oil and gas that have been cooled by heat exchanger 102 and oil and gas cooler 103, which come into contact with primary absorbent from primary cooler 106. Primary absorption tail gas is obtained at the top of the tower, and primary absorption liquid containing water and heavy hydrocarbons is obtained in the storage section at the bottom of the tower.

[0044] In the secondary absorption tower 107, the primary absorption tail gas comes into contact with the secondary absorbent from the secondary cooler 111, and the secondary absorption tail gas is obtained at the top of the tower, while the ice-containing secondary absorbent liquid is obtained at the bottom of the tower.

[0045] In the three-stage absorption tower 108, the secondary absorption tail gas comes into contact with a stream of secondary absorbent from the secondary cooler 111, and the tertiary absorption tail gas is obtained at the top of the tower and the tertiary absorption liquid is obtained at the bottom of the tower.

[0046] The filter 110 filters the ice-containing secondary absorbent obtained from the bottom of the secondary absorption tower 107 and the tertiary absorbent obtained from the tertiary absorption tower 108 to obtain ice particles and filtrate; and the obtained ice particles are transported to the storage section 104B at the bottom of the primary absorption tower 104 and the obtained filtrate is transported to the inlet of the secondary cooler 111.

[0047] The primary circulation pump 105 is used to circulate the primary absorbent in the lower storage section 104B of the primary absorption tower 104 to the inlet of the primary cooler 106, and then to the absorbent inlet at the upper part of the primary absorption tower 104.

[0048] The secondary circulation pump 109 is used to transport the ice-containing absorbent obtained from the secondary absorption tower 107 and the tertiary absorbent obtained from the tertiary absorption tower 108 to the filter 110, and to transport the secondary absorbent obtained from the filter 110 to the secondary cooler 111.

[0049] The primary absorption tower 104 has a cylindrical structure, comprising an upper absorption section 104A and a lower storage section 104B. The lower end of the absorption section 104A has a primary oil / gas inlet 1, and the upper end has a primary absorbent inlet 2. An absorbent spray system is located in the upper part of the cylinder, and the top end cap of the absorption section 104A has a primary absorption tail gas exhaust port 3. The storage section 104B has a primary absorbent liquid outlet 4 in the middle, an ice particle inlet 5 at the upper end, and a drain outlet 6 at the bottom end cap. The primary absorption tower 104 is preferably a packed tower. Packing material is installed below the spray system for absorbent distribution, enhancing gas-liquid mass and heat transfer. The spray system within the primary absorption tower is connected to the primary absorbent inlet 2, enabling the absorbent to be sprayed and dispersed within the tower.

[0050] The secondary absorption tower 107 has a cylindrical structure. The lower part of the absorption section is equipped with a secondary oil and gas inlet 7, and the upper part of the section is equipped with a secondary absorbent inlet 8. The upper part of the inner part of the section is also equipped with absorbent spraying facilities. The top end of the absorption section is equipped with a secondary absorption tail gas exhaust port 9, and the bottom end is equipped with a secondary absorbent liquid outlet 10.

[0051] The secondary absorption tower 107 is preferably a spray tower. A spray system is installed in the upper part of the secondary absorption tower 107, with an empty tower below the spray system. The spray system inside the secondary absorption tower is connected to the secondary absorbent inlet 8, enabling the absorbent to be sprayed and dispersed within the tower.

[0052] The three-stage absorption tower 108 has a cylindrical structure. The lower part of the absorption section is equipped with a three-stage oil and gas inlet 11, the upper part of the section is equipped with a three-stage absorbent inlet 12, the upper part of the internal space is equipped with an absorbent spraying facility, the top end of the absorption section is equipped with a purified gas exhaust port 13, and the bottom end is equipped with a three-stage absorbent liquid outlet 14.

[0053] The three-stage absorption tower 108 is preferably a packed tower. The lower cylinder of the three-stage spray tower 108 is filled with packing material for absorbent distribution and to enhance gas-liquid mass and heat transfer.

[0054] The top of the primary absorption tower 104, the secondary absorption tower 107, and the tertiary absorption tower 108 is preferably equipped with a demisting section, which is used to capture the mist droplets carried in the exhaust gas of each absorption tower.

[0055] The filter 110 includes a liquid inlet 15, an absorbent outlet 16 for discharging secondary absorbent liquid, and a slag outlet 17 for discharging ice particles.

[0056] Combination Figure 1 The working process of the cryogenic oil and gas recovery device provided by this utility model includes the following:

[0057] (1) The oil and gas to be processed is Stream I. Stream I is pressurized by the exhaust fan 101, cooled by the oil and gas cooler 102, and heated by the oil and gas heat exchanger 103. The resulting oil and gas is Stream II. Stream II enters the primary absorption tower 104.

[0058] (2) The oil and gas (material II) entering the first-stage absorption tower undergoes countercurrent mass transfer and heat transfer with the absorbent at 4~8℃ in the first-stage absorption tower. Most of the C6 and above components are absorbed and condensed into the absorbent. At the same time, the water in material II is cooled and separated. Most of the cooled water also enters the absorbent. The exhaust gas at the top of the first-stage absorption tower is the tail gas of the first-stage absorption tower (material III), which is sent to the second-stage absorption tower 107. The absorbent used in the first-stage absorption process is pressurized and circulated by the first-stage circulation pump 105. Before entering the first-stage absorption tower, the absorbent is cooled to 4~8℃ by the first-stage cooler 106 and then enters the first-stage absorption tower 104.

[0059] (3) The tail gas of the first-stage absorption tower (material III) enters the second-stage absorption tower 107 for absorption and treatment: Material III is in the second-stage absorption tower and undergoes countercurrent mass transfer and heat transfer with the absorbent at -65~-70℃. Most of the C3 and above components are absorbed and condensed into the absorbent. The water in material III comes into contact with the absorbent below zero and is directly condensed into ice particles. The exhaust gas at the top of the second-stage absorption tower is the tail gas of the second-stage absorption tower (material IV).

[0060] (4) The tail gas of the secondary absorption tower (material IV) enters the tertiary absorption tower 108 for absorption and treatment. In the tertiary absorption tower, material IV is again subjected to countercurrent mass transfer and heat transfer with the absorbent at -65~-70℃. The remaining C3 and above components are absorbed and condensed into the absorbent. The exhaust gas at the top of the tertiary absorption tower is the tail gas of the tertiary absorption tower (material IV).

[0061] (5) The absorbent used in the absorption process in the secondary absorption tower 107 and the tertiary absorption tower 108 is pressurized and circulated by the secondary circulation pump 109; the ice particles in the absorbent are filtered and separated in the filter 110, and the ice particles are sent to the primary absorption tower 104 through the pipeline. The filtrate enters the secondary cooler 111 and is cooled to -65~-70℃ before re-entering the secondary absorption tower 107 and the tertiary absorption tower 108 to absorb the oil and gas.

[0062] (6) The tail gas (material IV) of the three-stage absorption tower and the pressurized and cooled oil and gas exchange heat through the oil and gas heat exchanger 103 to obtain purified gas at a temperature of 40~45℃. The purified gas can be further sent to boilers, catalytic oxidation, regenerative oxidation and adsorption devices for further treatment to meet emission standards.

[0063] The operating pressure of the primary absorption tower is 0~200 kPa, and the absorption temperature is 4~8℃. The operating pressure of the secondary absorption tower is 0~200 kPa, and the absorption temperature is -65~-70℃. The operating pressure of the tertiary absorption tower is 0~200 kPa, and the absorption temperature is -65~-70℃.

[0064] The absorbents used in the primary, secondary, and tertiary absorption towers are oil products with a distillation range of 30~200℃, and the absorbents are recycled.

[0065] This novel low-temperature oil and gas recovery device uses a primary absorption tower to cool and separate most of the water and heavy components in the oil and gas; a secondary absorption tower to separate some of the C3-C5 components and the remaining water; and a tertiary absorption tower to separate the remaining C3-C5 components. It achieves high oil and gas recovery efficiency and good results, effectively avoiding the ice blockage problem in current condensation-based oil and gas recovery systems. It also extends the long-term recycling cycle of the absorbent and has advantages such as stable and reliable process, simple equipment, safety, and energy saving.

Claims

1. A cryogenic oil and gas recovery apparatus, characterized by, The application relates to an oil and gas recovery device. The device comprises: a first absorption tower, in which oil gas cooled by an oil gas cooler and an oil gas heat exchanger is contacted with a first absorption agent, and first absorption tail gas is obtained at the top of the tower, and first absorption liquid containing water and heavy hydrocarbon is obtained at the bottom of the tower; a second absorption tower, in which the first absorption tail gas is contacted with a second absorption agent from a second cooler, and second absorption tail gas and second absorption liquid containing ice particles are obtained; a third absorption tower, in which the second absorption tail gas is contacted with the second absorption agent from the second cooler, and purified gas and third absorption liquid are obtained; a filter, in which the second absorption liquid containing ice particles obtained from the second absorption tower and the third absorption liquid obtained from the third absorption tower are filtered, and ice particles and filtrate are obtained; the obtained ice particles are transported to the lower part of the first absorption tower, and the obtained filtrate is transported to the inlet of the second cooler; a first circulating pump, which is used for circulating the absorption liquid in the liquid storage section of the lower part of the first absorption tower to the absorption agent inlet of the upper part of the first absorption tower after passing through the first cooler; 2. The cryogenic oil and gas recovery apparatus of claim 1, wherein, a second circulating pump, which is used for transporting the second absorption liquid containing ice obtained from the second absorption tower and the third absorption liquid obtained from the third absorption tower to the filter, and transporting the second absorption agent obtained from the filter to the second cooler.

3. The cryogenic oil and gas recovery apparatus of claim 1, wherein, The device further comprises an air induction fan, which is used for inducing oil gas into the oil and gas recovery device.

4. The cryogenic oil and gas recovery apparatus of claim 3, wherein, The cylinder of the first absorption tower comprises an upper absorption section and a lower liquid storage section; a first absorption liquid outlet is arranged in the middle of the cylinder of the liquid storage section, an ice particle inlet is arranged at the upper end of the cylinder, and a water outlet is arranged on the bottom head of the liquid storage section.

5. The cryogenic oil and gas recovery apparatus of claim 1, wherein, The lower end of the cylinder of the absorption section of the first absorption tower is provided with a first oil gas inlet, the upper end of the cylinder is provided with a first absorption agent inlet, absorption agent spraying facilities are arranged in the cylinder, and a first absorption tail gas exhaust port is arranged on the top head of the absorption section.

6. The cryogenic oil vapor recovery unit of claim 1, wherein, The lower end of the cylinder of the second absorption tower is provided with a second oil gas inlet, the upper end of the cylinder is provided with a second absorption agent inlet, absorption agent spraying facilities are arranged in the upper part of the cylinder, a second absorption tail gas exhaust port is arranged on the top head of the absorption tower, and a second absorption liquid outlet is arranged on the bottom head.

7. The cryogenic oil vapor recovery unit of claim 1, wherein, The lower end of the cylinder of the third absorption tower is provided with a third oil gas inlet, the upper end of the cylinder is provided with a third absorption agent inlet, absorption agent spraying facilities are arranged in the upper part of the cylinder, a third absorption tail gas exhaust port is arranged on the top head of the absorption section, and a third absorption liquid outlet is arranged on the bottom head. The lower part of the spraying facilities in the first absorption tower is provided with a filler; and / or The lower part of the spraying facilities in the second absorption tower is empty; and / or 8. The cryogenic oil and gas recovery apparatus of claim 1, wherein, The lower part of the spraying facilities in the third absorption tower is provided with a filler. The top of the first absorption tower is provided with a demisting section; and / or The top of the second absorption tower is provided with a demisting section; and / or 9. The cryogenic oil and gas recovery apparatus of claim 1, wherein, The top of the third absorption tower is provided with a demisting section. The inlet of the first circulating pump is provided with a first liquid supplementing pipe; and / or 10. The cryogenic oil and gas recovery apparatus of claim 1, wherein, The inlet of the second circulating pump is provided with a second liquid supplementing pipe. The first circulating pump is a centrifugal pump; and / or The second circulating pump is a slurry pump.

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