A cold-carrying cycle heat recovery oil gas recovery system

Abstract

The present application relates to oil gas recovery technical field, disclose a kind of cold carrier circulation heat recovery oil gas recovery system, comprising: oil gas cooling liquefaction recovery subsystem and cold carrier circulation heat recovery subsystem;The oil gas cooling liquefaction recovery subsystem includes sequentially communicated first-stage cooling module, second-stage cooling module, third-stage cooling module and four-stage temperature rising module by oil gas connecting pipe;The cold carrier circulation heat recovery subsystem includes first-stage oil gas condenser A, first-stage oil gas condenser B, first cold carrier valve, second cold carrier valve, third cold carrier valve, fourth cold carrier valve, fifth cold carrier valve, sixth cold carrier valve, cold carrier pump and four-stage oil gas heater.The cold carrier circulation heat recovery oil gas recovery system provided by the present application has the advantages of low energy consumption, energy saving and environmental protection, simple refrigeration system, low cost, high reliability and other advantages, which greatly improves the energy saving and environmental protection of oil gas recovery system, cost performance and operation reliability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil gas recovery, in particular to a cold-carrying cycle heat recovery oil gas recovery system. BACKGROUND

[0002] At present, there is an ordinary oil gas recovery system, which can be used for multi-stage deep cooling, and the lowest cooling temperature can reach about-70 DEG C. The system is used for condensation and liquefaction recovery of volatile organic compounds in oil gas (VOCs gas), reduces environmental pollution, and the recovered volatile organic compounds can also produce considerable economic benefits.

[0003] However, after the ordinary oil gas recovery system cools the imported oil gas in multiple stages, the oil gas is cooled to-70 DEG C. The-70 DEG C oil gas tail gas recovered by cooling is generally directly discharged into the atmosphere, or a heating device is additionally provided to heat the low-temperature oil gas to about 10 DEG C before discharging it into the atmosphere. However, the-70 DEG C oil gas tail gas at the outlet of the last-stage cold-carrying cycle heat recovery oil gas recovery system has a lot of high-grade refrigeration capacity, which is discharged into the atmosphere or set to consume energy for heating the low-temperature oil gas before discharging. This way makes the traditional oil gas recovery system have problems such as high energy consumption, serious pollution, complex refrigeration system, high cost, low reliability and the like, which seriously limits the development of oil gas condensation equipment.

[0004] Therefore, the prior art still needs to be improved and improved. SUMMARY

[0005] In view of the above problems of the prior art, the present application aims to provide a cold-carrying cycle heat recovery oil gas recovery system, which aims to solve the problems of high energy consumption, serious pollution, complex refrigeration system, high cost and low reliability of the traditional oil gas recovery system.

[0006] In order to achieve the above-mentioned purpose, the present application adopts the following technical scheme:

[0007] A cold-carrying cycle heat recovery oil gas recovery system, characterized in that it comprises an oil gas cooling and liquefaction recovery subsystem and a cold-carrying cycle heat recovery subsystem.

[0008] The oil and gas cooling liquefied recovery subsystem comprises a first-stage cooling module, a second-stage cooling module, a third-stage cooling module and a fourth-stage heating module connected in sequence through an oil and gas connecting pipe; wherein the first-stage cooling module comprises an oil and gas inlet (21), a first-stage cooling tank A (22), a first-stage cooling tank B (23), a first oil and gas valve (24), a second oil and gas valve (25) and a first oil and gas connecting pipe (26); the oil and gas inlet (21) is divided into two paths, one path is connected with one end of the first-stage cooling tank A (22), and the other end of the first-stage cooling tank A (22) is connected with one end of the first oil and gas valve (24); the other path is connected with one end of the first-stage cooling tank B (23), and the other end of the first-stage cooling tank B (23) is connected with one end of the second oil and gas valve (25); the other end of the first oil and gas valve (24) is connected with the other end of the second oil and gas valve (25), and is connected with one end of the first oil and gas connecting pipe (26);

[0009] The cold carrier circulation heat recovery subsystem comprises a first-stage oil and gas condenser A (31) installed in the first-stage cooling tank A (22), a first-stage oil and gas condenser B (32) installed in the first-stage cooling tank B (23), a first cold carrier valve (33), a second cold carrier valve (34), a third cold carrier valve (35), a fourth cold carrier valve (36), a fifth cold carrier valve (37), a sixth cold carrier valve (38), a cold carrier pump (39) and a fourth-stage oil and gas heater (310); wherein the cold carrier outlet of the first-stage oil and gas condenser A (31) is divided into two paths, one path is connected with one end of the first cold carrier valve (33), and the other path is connected with one end of the second cold carrier valve (34); the other end of the first cold carrier valve (33) is connected with the cold carrier outlet of the first-stage oil and gas condenser B (32); the other end of the second cold carrier valve (34) is connected with one end of the cold carrier pump (39), the other end of the cold carrier pump (39) is connected with the cold carrier inlet of the fourth-stage oil and gas heater (310), the cold carrier outlet of the fourth-stage oil and gas heater (310) is divided into two paths, one path is connected with one end of the fourth cold carrier valve (36), and the other path is connected with one end of the sixth cold carrier valve (38); the other end of the fourth cold carrier valve (36) is divided into two paths, one path is connected with the cold carrier inlet of the first-stage oil and gas condenser A (31), and the other path is connected with one end of the fifth cold carrier valve (37); the other end of the sixth cold carrier valve (38) is divided into two paths, one path is connected with the cold carrier inlet of the first-stage oil and gas condenser B (32), and the other path is connected with one end of the third cold carrier valve (35); the other end of the third cold carrier valve (35) is connected with the connecting pipe of the second cold carrier valve (34) and the cold carrier pump (39); the other end of the fifth cold carrier valve (37) is connected with the connecting pipe of the first cold carrier valve (33) and the cold carrier outlet of the first-stage oil and gas condenser B (32).

[0010] The oil gas recovery system of the cold-carrying cycle heat recovery, wherein the secondary cooling module comprises a secondary oil gas condenser A (27), a secondary oil gas condenser B (28), a third oil gas valve (29), a fourth oil gas valve (210), and a second oil gas connecting pipe (211); the other end of the first oil gas connecting pipe (26) is divided into two paths, one of which is connected with one end of the secondary oil gas condenser A (27), and the other of which is connected with one end of the secondary oil gas condenser B (28); the other end of the secondary oil gas condenser A (27) is connected with one end of the third oil gas valve (29), the other end of the secondary oil gas condenser B (28) is connected with one end of the fourth oil gas valve (210), the other end of the third oil gas valve (29) is connected with the other end of the fourth oil gas valve (210), and one end of the second oil gas connecting pipe (211) is connected with the third oil gas valve (29).

[0011] The oil gas recovery system of the cold-carrying cycle heat recovery, wherein the secondary cooling module comprises a secondary oil gas condenser A (27), a secondary oil gas condenser B (28), a third oil gas valve (29), a fourth oil gas valve (210), and a second oil gas connecting pipe (211); the other end of the first oil gas connecting pipe (26) is divided into two paths, one of which is connected with one end of the secondary oil gas condenser A (27), and the other of which is connected with one end of the secondary oil gas condenser B (28); the other end of the secondary oil gas condenser A (27) is connected with one end of the third oil gas valve (29), the other end of the secondary oil gas condenser B (28) is connected with one end of the fourth oil gas valve (210), the other end of the third oil gas valve (29) is connected with the other end of the fourth oil gas valve (210), and one end of the second oil gas connecting pipe (211) is connected with the third oil gas valve (29).

[0012] The oil gas recovery system of the cold-carrying cycle heat recovery, wherein the secondary cooling module comprises a secondary oil gas condenser A (27), a secondary oil gas condenser B (28), a third oil gas valve (29), a fourth oil gas valve (210), and a second oil gas connecting pipe (211); the other end of the first oil gas connecting pipe (26) is divided into two paths, one of which is connected with one end of the secondary oil gas condenser A (27), and the other of which is connected with one end of the secondary oil gas condenser B (28); the other end of the secondary oil gas condenser A (27) is connected with one end of the third oil gas valve (29), the other end of the secondary oil gas condenser B (28) is connected with one end of the fourth oil gas valve (210), the other end of the third oil gas valve (29) is connected with the other end of the fourth oil gas valve (210), and one end of the second oil gas connecting pipe (211) is connected with the third oil gas valve (29).

[0013] The oil gas recovery system of the cold-carrying cycle heat recovery, wherein the secondary cooling module comprises a secondary oil gas condenser A (27), a secondary oil gas condenser B (28), a third oil gas valve (29), a fourth oil gas valve (210), and a second oil gas connecting pipe (211); the other end of the first oil gas connecting pipe (26) is divided into two paths, one of which is connected with one end of the secondary oil gas condenser A (27), and the other of which is connected with one end of the secondary oil gas condenser B (28); the other end of the secondary oil gas condenser A (27) is connected with one end of the third oil gas valve (29), the other end of the secondary oil gas condenser B (28) is connected with one end of the fourth oil gas valve (210), the other end of the third oil gas valve (29) is connected with the other end of the fourth oil gas valve (210), and one end of the second oil gas connecting pipe (211) is connected with the third oil gas valve (29).

[0014] Beneficial effects:

[0015] The application provides a cold carrier circulation heat recovery oil gas recovery system, which adopts high-temperature cold carriers discharged from a first-stage oil gas condenser in a cold carrier circulation heat recovery subsystem, absorbs the cold quantity of oil gas tail gas at about-70 DEG C through a fourth-stage oil gas heater, is cooled to become low-temperature cold carriers, and simultaneously heats the-70 DEG C oil gas tail gas to be discharged at about 10 DEG C; the low-temperature cold carriers enter the first-stage oil gas condenser again, release the cold quantity to reduce the temperature of imported oil gas, absorb the heat of the imported oil gas to be heated to become high-temperature cold carriers, and the cycle operation is realized; based on the cold carrier circulation heat recovery subsystem, the cold quantity of the oil gas tail gas at about-70 DEG C can be effectively recovered to replace the compressor refrigeration for providing the refrigeration quantity for the first-stage oil gas condenser, the compressor configuration of the first-stage oil gas condenser is reduced, and the energy utilization rate of the oil gas recovery unit is greatly improved. The cold carrier circulation heat recovery oil gas recovery system provided by the application has the advantages of low energy consumption, energy saving and environmental protection, simple refrigeration system, low cost, high reliability and the like, and the energy saving and environmental protection performance, cost performance and operation reliability of the oil gas recovery system are greatly improved. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 The application provides a cold carrier circulation heat recovery oil gas recovery system.

[0017] Main element symbol explanation: 21-oil gas inlet, 22-first-stage cooling box A, 23-first-stage cooling box B, 24-first oil gas valve, 25-second oil gas valve, 26-first oil gas connecting pipe, 27-second-stage oil gas condenser A, 28-second-stage oil gas condenser B, 29-third oil gas valve, 210-fourth oil gas valve, 211-second oil gas connecting pipe, 212-third-stage oil gas condenser A, 213-third-stage oil gas condenser B, 214-fifth oil gas valve, 215-sixth oil gas valve, 216-third oil gas connecting pipe, 217-fourth-stage heating box, 218-oil gas outlet, 219-liquid oil outlet pipe. DETAILED DESCRIPTION

[0018] The application provides a cold carrier circulation heat recovery oil gas recovery system, and the purpose, technical scheme and effects of the application are more clearly and definitely described below by referring to the drawings and taking examples to make further detailed description.

[0019] In the description of the application, it should be understood that the orientation or position relationship indicated by the terms "top", "bottom" and the like is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the application and simplifying the description, and cannot be understood as a limitation on the application; in addition, the terms "mounting", "connecting" and the like should be understood in a broad sense, and those skilled in the art can understand the specific meanings of the above terms in the application according to specific circumstances.

[0020] In traditional oil and gas recovery systems, the exhaust gas at around -70°C after multi-stage cooling of imported oil and gas is simply released into the atmosphere or even requires energy to be consumed to heat the low-temperature oil and gas before being released. This fails to effectively recover and utilize the high-grade cooling capacity of the -70°C exhaust gas, resulting in problems such as high energy consumption, significant pollution, complex refrigeration systems, high costs, and low reliability in traditional oil and gas recovery systems.

[0021] To address the problems of traditional oil and gas recovery systems, this invention provides a cooling cycle heat recovery oil and gas recovery system, such as... Figure 1 As shown, it includes: an oil and gas cooling liquefaction and recovery subsystem and a cooling cycle heat recovery subsystem; the oil and gas cooling liquefaction and recovery subsystem includes a primary cooling module, a secondary cooling module, a tertiary cooling module, and a quaternary heating module connected sequentially through an oil and gas connecting pipe; wherein, the primary cooling module includes: an oil and gas inlet (21), a primary cooling box A (22), a primary cooling box B (23), a first oil and gas valve (24), a second oil and gas valve (25), and a first oil and gas connecting pipe (26). 6); The oil and gas inlet (21) is divided into two paths. One path is connected to one end of the first-stage cooling box A (22), and the other end of the cooling box A (22) is connected to one end of the first oil and gas valve (24); the other path is connected to one end of the first-stage cooling box B (23), and the other end of the first-stage cooling box B (23) is connected to one end of the second oil and gas valve (25); the other end of the first oil and gas valve (24) is connected to the other end of the second oil and gas valve (25), and is connected to one end of the first oil and gas connecting pipe (26);

[0022] The cold-carrying circulating heat recovery subsystem comprises: a first-stage oil-gas condenser A (31) installed in a first-stage cooling oil tank A (22), a first-stage oil-gas condenser B (32) installed in a first-stage cooling oil tank B (23), a first cold-carrying agent valve (33), a second cold-carrying agent valve (34), a third cold-carrying agent valve (35), a fourth cold-carrying agent valve (36), a fifth cold-carrying agent valve (37), a sixth cold-carrying agent valve (38), a cold-carrying agent pump (39), and a fourth-stage oil-gas heater (310); wherein the cold-carrying agent outlet of the first-stage oil-gas condenser A (31) is divided into two paths, one of which is connected with one end of the first cold-carrying agent valve (33), and the other of which is connected with one end of the second cold-carrying agent valve (34); the other end of the first cold-carrying agent valve (33) is connected with the cold-carrying agent outlet of the first-stage oil-gas condenser B (32); the other end of the second cold-carrying agent valve (34) is connected with one end of the cold-carrying agent pump (39), the other end of the cold-carrying agent pump (39) is connected with the cold-carrying agent inlet of the fourth-stage oil-gas heater (310), the cold-carrying agent outlet of the fourth-stage oil-gas heater (310) is divided into two paths, one of which is connected with one end of the fourth cold-carrying agent valve (36), and the other of which is connected with one end of the sixth cold-carrying agent valve (38); the other end of the fourth cold-carrying agent valve (36) is divided into two paths, one of which is connected with the cold-carrying agent inlet of the first-stage oil-gas condenser A (31), and the other of which is connected with one end of the fifth cold-carrying agent valve (37); the other end of the sixth cold-carrying agent valve (38) is divided into two paths, one of which is connected with the cold-carrying agent inlet of the first-stage oil-gas condenser B (32), and the other of which is connected with one end of the third cold-carrying agent valve (35); the other end of the third cold-carrying agent valve (35) is connected with the connecting pipe of the second cold-carrying agent valve (34) and the cold-carrying agent pump (39); and the other end of the fifth cold-carrying agent valve (37) is connected with the connecting pipe of the first cold-carrying agent valve (33) and the cold-carrying agent outlet of the first-stage oil-gas condenser B (32).

[0023] In the present application, for the cold-carrying agent side, when the first-stage oil-gas condenser A is not frosted, and the first-stage oil-gas condenser B is frosted, the cold-carrying agent valve is used to control the flow direction of the cold-carrying agent, the higher-temperature cold-carrying agent from the first-stage oil-gas condenser A in the cold-carrying circulating heat recovery subsystem first passes through the first-stage oil-gas condenser B, is used to heat the frosted first-stage oil-gas condenser B, and defrosts the same; then absorbs the coldness of the oil-gas tail gas at about -70 DEG C through the fourth-stage oil-gas heater, is cooled to become lower-temperature cold-carrying agent, and at the same time, heats the oil-gas tail gas at -70 DEG C to about 10 DEG C for discharge; the lower-temperature cold-carrying agent enters the first-stage oil-gas condenser A again, radiates coldness to reduce the temperature of the imported oil-gas, absorbs the heat of the imported oil-gas to become higher-temperature cold-carrying agent;

[0024] When the primary oil-gas condenser A is frosted while the primary oil-gas condenser B is not, the refrigerant flow direction is switched using a refrigerant valve. The higher-temperature refrigerant from the primary oil-gas condenser B in the refrigerant circulation heat recovery subsystem first passes through the primary oil-gas condenser A to heat the frosted primary oil-gas condenser A and defrost it. Then, it passes through the fourth-stage oil-gas heater to absorb the cold energy of the oil-gas exhaust gas at around -70°C, cooling it down to become a lower-temperature refrigerant. At the same time, it heats the -70°C oil-gas exhaust gas to around 10°C before discharging it. The lower-temperature refrigerant enters the primary oil-gas condenser B, where it releases its cold energy to lower the temperature of the inlet oil-gas and absorbs the heat from the inlet oil-gas to become a higher-temperature refrigerant. This cycle continues in this manner.

[0025] Regarding the oil and gas side, when the first-stage oil and gas condenser A is not frosted while the first-stage oil and gas condenser B is frosted, an oil and gas valve is used to control the flow of oil and gas through the first-stage oil and gas cooling box A; when the first-stage oil and gas condenser A is frosted while the first-stage oil and gas condenser B is not frosted, an oil and gas valve is used to switch the flow of oil and gas through the first-stage oil and gas cooling box B.

[0026] This invention, based on a refrigerant-cooled cycle heat recovery subsystem, can effectively recover the cooling capacity of oil and gas exhaust gases at approximately -70°C. This subsystem replaces the original compressor-based refrigeration system that provides cooling capacity to the primary oil and gas condenser, reducing the compressor requirements of the primary condenser and significantly improving the energy efficiency of the oil and gas recovery unit. By cyclically switching the refrigerant flow direction, it cleverly achieves cooling, frosting, and defrosting cycles, thereby effectively ensuring the normal and stable operation of the refrigerant-cooled cycle heat recovery system. The refrigerant-cooled cycle heat recovery oil and gas recovery system provided by this invention has advantages such as low energy consumption, energy saving and environmental protection, simple refrigeration system, low cost, and high reliability, significantly improving the energy efficiency, environmental friendliness, cost-effectiveness, and operational reliability of oil and gas recovery systems.

[0027] In some implementations, such as Figure 1 As shown, the secondary cooling module includes a secondary oil-gas condenser A (27), a secondary oil-gas condenser B (28), a third oil-gas valve (29), a fourth oil-gas valve (210), and a second oil-gas connecting pipe (211). The other end of the first oil-gas connecting pipe (26) is divided into two paths, one of which is connected to one end of the secondary oil-gas condenser A (27), and the other is connected to one end of the secondary oil-gas condenser B (28). The other end of the secondary oil-gas condenser A (27) is connected to one end of the third oil-gas valve (29), the other end of the secondary oil-gas condenser B (28) is connected to one end of the fourth oil-gas valve (210), the other end of the third oil-gas valve (29) is connected to the other end of the fourth oil-gas valve (210), and is connected to one end of the second oil-gas connecting pipe (211).

[0028] In this embodiment, the high-temperature and high-pressure oil and gas are partially liquefied after being cooled by the first-stage cooling module. The remaining oil and gas continue to enter the second-stage cooling module through the first oil and gas connecting pipe (26) for further cooling. By controlling the opening and closing of the third oil and gas valve (29) and the fourth oil and gas valve (210), the remaining oil and gas can be further cooled and liquefied by the second-stage oil and gas condenser A (27) or the second-stage oil and gas condenser B (28). Specifically, by controlling the opening of the third oil and gas valve (29) and the closing of the fourth oil and gas valve (210), the remaining oil and gas are cooled and liquefied through the secondary oil and gas condenser A (27). During this process, if frost is detected on the secondary oil and gas condenser A (27), the third oil and gas valve (29) is closed and the fourth oil and gas valve (210) is opened, so that the remaining oil and gas are cooled and liquefied through the secondary oil and gas condenser B (28). In this way, by switching the direction of oil and gas flow in a cycle, the cooling, frosting and defrosting cycle can be cleverly realized, thereby effectively ensuring the normal and stable operation of the cooling cycle oil and gas recovery system.

[0029] In some implementations, such as Figure 1 As shown, the three-stage cooling module includes a three-stage oil-gas condenser A (212), a three-stage oil-gas condenser B (213), a fifth oil-gas valve (214), a sixth oil-gas valve (215), and a third oil-gas connecting pipe (216); the other end of the second oil-gas connecting pipe (211) is divided into two paths, one path is connected to one end of the three-stage oil-gas condenser A (212), and the other path is connected to one end of the three-stage oil-gas condenser B (213); the other end of the three-stage oil-gas condenser A (212) is connected to one end of the fifth oil-gas valve (214), the other end of the three-stage oil-gas condenser B (214) is connected to one end of the sixth oil-gas valve (215), the other end of the fifth oil-gas valve (214) is connected to the other end of the sixth oil-gas valve (215), and is connected to one end of the third oil-gas connecting pipe (216).

[0030] In the embodiment, the remaining oil gas cooled by the secondary cooling module can enter the tertiary cooling module for further cooling through the second oil gas connecting pipe (211), and the further cooling and liquefaction of the remaining oil gas through the tertiary oil gas condenser A (212) or the tertiary oil gas condenser B (213) can be realized by controlling the opening and closing of the fifth oil gas valve (214) and the sixth oil gas valve (215). Specifically, by controlling the fifth oil gas valve (214) to be opened and the sixth oil gas valve (215) to be closed, the remaining oil gas is cooled and liquefied through the tertiary oil gas condenser A (212), and in this process, if frost is monitored on the tertiary oil gas condenser A (212), the fifth oil gas valve (214) is controlled to be closed and the sixth oil gas valve (215) is controlled to be opened, so that the remaining oil gas is cooled and liquefied through the tertiary oil gas condenser B (213). By cyclically switching the oil gas flow direction, cooling, frosting and defrosting cycles can be realized, thereby effectively ensuring the normal and stable operation of the cold-carrying cycle oil gas recovery system.

[0031] In some embodiments, as shown in Figure 1 The fourth oil gas heater (310) is installed in the fourth heating tank (217).

[0032] In the embodiment, the low-temperature (-70°C or so) oil gas tail gas cooled by the tertiary cooling module enters the fourth heating tank (217) installed with the fourth oil gas heater (310) through the third oil gas connecting pipe (216). At this time, since the cold carrier becomes a higher-temperature cold carrier after cooling the high-temperature and high-pressure oil gas in the primary oil gas condenser, the higher-temperature cold carrier can absorb the cold energy of the -70°C or so oil gas tail gas through the fourth oil gas heater, become a lower-temperature cold carrier, and heat the -70°C oil gas tail gas to about 10°C for discharge. The lower-temperature cold carrier enters the primary oil gas condenser, releases cold energy to reduce the temperature of the imported oil gas, absorbs the heat of the imported oil gas to become a higher-temperature cold carrier, and so on. Based on the cold-carrying cycle heat recovery subsystem, the cold energy of the -70°C or so oil gas tail gas can be effectively recovered to replace the compressor refrigeration for providing refrigeration capacity for the primary oil gas condenser, reduce the configuration of the compressor of the primary oil gas condenser, and greatly improve the energy utilization rate of the oil gas recovery unit.

[0033] In some embodiments, as shown in Figure 1As shown, the liquid oil outlet pipe (219) is connected with the liquid oil outlet of the first-stage cooling tank A (22), the liquid oil outlet of the first-stage cooling tank B (23), the liquid oil outlet of the second-stage oil gas condenser A (27), the liquid oil outlet of the second-stage oil gas condenser B (28), the liquid oil outlet of the third-stage oil gas condenser A (212), and the liquid oil outlet of the third-stage oil gas condenser B (213).

[0034] In the embodiment, the volatile organic compounds in the high-temperature and high-pressure oil gas are condensed and liquefied in the cooling process at different stages, and then recovered through the liquid oil outlet pipe (219).

[0035] In summary, the present application uses the higher-temperature cold carrier from the first-stage oil gas condenser in the cold carrier circulation heat recovery subsystem to absorb the cold quantity of the oil gas tail gas at about -70 DEG C through the four-stage oil gas heater, and the cold carrier is cooled to become lower-temperature cold carrier, and the -70 DEG C oil gas tail gas is heated to about 10 DEG C for discharge; the lower-temperature cold carrier enters the first-stage oil gas condenser again to release cold quantity for reducing the temperature of the imported oil gas, and absorbs the heat of the imported oil gas to become higher-temperature cold carrier, and the cycle is repeated; the present application is based on the cold carrier circulation heat recovery subsystem, and can effectively recover the cold quantity of the oil gas tail gas at about -70 DEG C to replace the compressor refrigeration for providing refrigeration quantity for the first-stage oil gas condenser, and reduce the compressor configuration of the first-stage oil gas condenser, and greatly improve the energy utilization rate of the oil gas recovery unit. The cold carrier circulation heat recovery oil gas recovery system provided by the present application has the advantages of low energy consumption, energy saving and environmental protection, simple refrigeration system, low cost, high reliability, and the like, and greatly improves the energy saving and environmental protection, cost performance, and operation reliability of the oil gas recovery system.

[0036] It can be understood that, for those skilled in the art, equivalent replacements or changes can be made according to the technical solutions and the inventive concept of the present application, and all the changes or replacements shall belong to the protection scope of the present application.

Claims

1. A subcooling heat recovery oil vapor recovery system characterized by, The application relates to an oil-gas cooling liquefaction recovery subsystem and a cold carrier circulation heat recovery subsystem. The oil-gas cooling liquefaction recovery subsystem comprises a first-stage cooling module, a second-stage cooling module, a third-stage cooling module and a fourth-stage heating module which are sequentially connected through an oil-gas connecting pipe; the first-stage cooling module comprises an oil-gas inlet (21), a first-stage cooling tank A (22), a first-stage cooling tank B (23), a first oil-gas valve (24), a second oil-gas valve (25) and a first oil-gas connecting pipe (26); the oil-gas inlet (21) is divided into two paths, one path is connected with one end of the first-stage cooling tank A (22), and the other end of the first-stage cooling tank A (22) is connected with one end of the first oil-gas valve (24); the other path is connected with one end of the first-stage cooling tank B (23), and the other end of the first-stage cooling tank B (23) is connected with one end of the second oil-gas valve (25); the other end of the first oil-gas valve (24) is connected with the other end of the second oil-gas valve (25), and one end of the first oil-gas connecting pipe (26) is connected with the first oil-gas valve (24) and the second oil-gas valve (25); The liquid oil outlet pipe (219) is connected with the liquid oil outlet of the first-stage cooling tank A (22), the liquid oil outlet of the first-stage cooling tank B (23), the liquid oil outlet of the second-stage oil-gas condenser A (27), the liquid oil outlet of the second-stage oil-gas condenser B (28), the liquid oil outlet of the third-stage oil-gas condenser A (212) and the liquid oil outlet of the third-stage oil-gas condenser B (213). The cold carrier circulation heat recovery subsystem comprises a first-stage oil-gas condenser A (31) installed in a first-stage cooling oil tank A (22), a first-stage oil-gas condenser B (32) installed in a first-stage cooling oil tank B (23), a first cold carrier valve (33), a second cold carrier valve (34), a third cold carrier valve (35), a fourth cold carrier valve (36), a fifth cold carrier valve (37), a sixth cold carrier valve (38), a cold carrier pump (39), and a fourth-stage oil-gas heater (310); wherein the cold carrier outlet of the first-stage oil-gas condenser A (31) is divided into two paths, one of which is connected with one end of the first cold carrier valve (33), and the other of which is connected with one end of the second cold carrier valve (34); the other end of the first cold carrier valve (33) is connected with the cold carrier outlet of the first-stage oil-gas condenser B (32); the other end of the second cold carrier valve (34) is connected with one end of the cold carrier pump (39), the other end of the cold carrier pump (39) is connected with the cold carrier inlet of the fourth-stage oil-gas heater (310), the cold carrier outlet of the fourth-stage oil-gas heater (310) is divided into two paths, one of which is connected with one end of the fourth cold carrier valve (36), and the other of which is connected with one end of the sixth cold carrier valve (38); the other end of the fourth cold carrier valve (36) is divided into two paths, one of which is connected with the cold carrier inlet of the first-stage oil-gas condenser A (31), and the other of which is connected with one end of the fifth cold carrier valve (37); the other end of the sixth cold carrier valve (38) is divided into two paths, one of which is connected with the cold carrier inlet of the first-stage oil-gas condenser B (32), and the other of which is connected with one end of the third cold carrier valve (35); the other end of the third cold carrier valve (35) is connected with the connecting pipe of the second cold carrier valve (34) and the cold carrier pump (39); the other end of the fifth cold carrier valve (37) is connected with the connecting pipe of the first cold carrier valve (33) and the cold carrier outlet of the first-stage oil-gas condenser B (32); the second-stage cooling module comprises a second-stage oil-gas condenser A (27), a second-stage oil-gas condenser B (28), a third oil-gas valve (29), a fourth oil-gas valve (210), and a second oil-gas connecting pipe (211); the other end of the first oil-gas connecting pipe (26) is divided into two paths, one of which is connected with one end of the second-stage oil-gas condenser A (27), and the other of which is connected with one end of the second-stage oil-gas condenser B (28); the other end of the second-stage oil-gas condenser A (27) is connected with one end of the third oil-gas valve (29), the other end of the second-stage oil-gas condenser B (28) is connected with one end of the fourth oil-gas valve (210), the other end of the third oil-gas valve (29) is connected with the other end of the fourth oil-gas valve (210), and is connected with one end of the second oil-gas connecting pipe (211); the third-stage cooling module comprises a third-stage oil-gas condenser A (212), a third-stage oil-gas condenser B (213), a fifth oil-gas valve (214), a sixth oil-gas valve (215), and a third oil-gas connecting pipe (216).The other end of the second oil and gas connecting pipe (211) is divided into two ways, one of which is connected with one end of the third oil and gas condenser A (212), and the other of which is connected with one end of the third oil and gas condenser B (213); the other end of the third oil and gas condenser A (212) is connected with one end of the fifth oil and gas valve (214), and the other end of the third oil and gas condenser B (213) is connected with one end of the sixth oil and gas valve (215); the other end of the fifth oil and gas valve (214) is connected with the other end of the sixth oil and gas valve (215), and one end of the third oil and gas connecting pipe (216) is connected with the other end of the fifth oil and gas valve (214) and the sixth oil and gas valve (215); the fourth temperature rising module comprises a fourth temperature rising box (217) connected with the other end of the third oil and gas connecting pipe (216), and the other end of the fourth temperature rising box (217) is connected with an oil and gas outlet (218); the fourth oil and gas heater (310) is installed in the fourth temperature rising box (217).

2. The subcooling cycle heat recovery oil gas recovery system according to claim 1, characterized by, ​

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