Regeneration tail gas recovery device and process for triethylene glycol dehydration skid of gas collection station

Abstract

The invention provides a gas gathering station triethylene glycol dehydration skid regeneration tail gas recovery device and process, and the regeneration tail gas recovery device comprises an emergency cut-off unit, a tail gas pressurization unit, a tail gas cooling unit and a tail gas separation unit which are sequentially communicated through a pipeline; a gas phase separated by the tail gas separation unit enters a flash steam recycling and collecting system; and the liquid phase separated by the tail gas separation unit is pressurized and then discharged to the produced liquid buffer tank. The whole recovery process is hermetically connected through a pipeline to ensure that the whole gas collection process is closed. Compared with a traditional recovery mode in which combustion of an incinerator is converted into a flash steam recovery and collection system, the method has the advantages that in the regeneration tail gas recovery process, the separated gas phase is sent to the flash steam recovery and collection system, environmental pollution caused by triethylene glycol dehydration skid regeneration tail gas emission and combustion is effectively treated, and meanwhile, the recovery efficiency of triethylene glycol dehydration skid regeneration tail gas is improved. And the tail gas contains a small amount of methane and alkane, so that the effects of energy conservation and emission reduction can be achieved.

Description

Technical Field

[0001] The present invention belongs to the field of triethylene glycol dehydration process equipment, and particularly relates to a regeneration tail gas recovery device and process for a triethylene glycol dehydration skid in a gas gathering station. Background Art

[0002] The surface system of a gas field mainly consists of gas wells, gas gathering stations, and purification (treatment) plants. Among them, the gas gathering stations in the Lower Paleozoic (sulfur-containing) gas fields mainly undertake the work of natural gas gathering, separation, dehydration, and boosting. The water in the Lower Paleozoic (sulfur-containing) natural gas has a greater impact on the transportation and use of natural gas. When economic conditions permit, it is necessary to remove the water in natural gas as much as possible. Triethylene glycol dehydration, as a method for natural gas dehydration, has been widely used. According to the operation effect, dry gas transportation has become an effective measure to control corrosion in pipelines, effectively improving the safety and reliability of natural gas transportation.

[0003] The triethylene glycol dehydration process is as follows:

[0004] The raw material gas from the well station first enters a filter separator for pretreatment to separate the solid and liquid impurities in the gas. After treatment, the wet natural gas enters from the lower part of the absorption tower and contacts the TEG lean liquid at the upper part of the absorption tower countercurrently in the tower. The saturated water in the natural gas is absorbed by the TEG and removed. The dehydrated natural gas is heat-exchanged and separated through a dry gas-lean liquid heat exchanger at the top of the TEG absorption tower and then exported; the TEG rich liquid is discharged from the liquid collection tank at the lower part of the absorption tower, passes through a level control valve, and then enters the top coil of the rich liquid rectification column of the reboiler for heat exchange and then enters the TEG flash tank, where H 2 S, CO 2 、H 2 O and a small amount of gases such as hydrocarbons are flashed out; the flashed TEG rich liquid enters the TEG mechanical filter and activated carbon filter through a level control valve to remove impurities and degradation products; thereafter, the rich liquid enters the heat exchange coil in the triethylene glycol buffer tank to exchange heat with the hot TEG lean liquid. After the rich liquid is heated, it enters the rich liquid rectification column on the triethylene glycol regeneration tower; the regenerated TEG lean liquid exchanges heat with the rich liquid in the triethylene glycol buffer tank, is cooled by water, enters the TEG circulation pump to boost the pressure after cooling, and then enters the upper part of the TEG absorption tower after further cooling through the dry gas-lean liquid heat exchanger, completing the TEG absorption and regeneration cycle process.

[0005] In the above process flow, the regeneration temperature of the reboiler in the regeneration tower is about 200°C, the molar ratio of water vapor in the gas discharged from the top of the regeneration tower is 93%, and the temperature is 93°C - 103°C. The main components are H 2 S, CO 2 、H 2 O and hydrocarbon gases. The amount of regeneration tail gas generated by a gas gathering station with a capacity of (30 - 200) 10,000 m³ / day is about (25 - 127) m 3 / h. At present, the regeneration tail gas of some Lower Paleozoic gas gathering stations is burned through a tail gas incinerator, and the regeneration tail gas of some stations is directly discharged into the atmosphere.

[0006] The process flow of burning the regenerated tail gas of the gas gathering station in the tail gas incinerator is shown in Figure 1 , according to Figure 1 As shown, the regenerated tail gas of the triethylene glycol dehydration skid is cooled by an aluminum radiator fin pipeline from the exhaust port of the distillation column of the dehydration skid and then enters the gas-liquid separator. The separated gas phase enters the positive pressure incinerator of the dehydration skid tail gas for combustion and is then converted into sulfur dioxide and discharged into the atmosphere. The liquid phase flows by gravity into the atmospheric underground sewage tank in the station; however, there are the following problems with this treatment process:

[0007] (1) According to the on-site analysis results, the concentration of SO 2 in the regenerated tail gas of the gas gathering station is 6032 mg / m 3 , which is much higher than the maximum allowable emission concentration of 960 mg / m 3 required by GB16297. In addition, the non-methane total hydrocarbon emission concentration is about 3200 mg / m 3 , which is much higher than the technical index of non-methane total hydrocarbon emission concentration ≤ 120 mg / m 3 ; (2) Due to the implementation of VOCs treatment, in accordance with Article 5.7.3 of GB 39728: "The whole process of collecting, treating, and transporting the well products produced by gas wells in the gas field shall adopt a closed process flow", the underground sewage tank in the station was replaced with a pressure buffer tank, resulting in the inability of the separated liquid phase to enter the sewage storage facility by gravity; (3) According to the gas gathering station with a capacity of 1 million cubic meters per day, this process consumes 385 m 3 / d of natural gas, which does not meet the current requirements of energy conservation, emission reduction, quality improvement, and efficiency increase. Summary of the Invention

[0008] The purpose of the present invention is to provide a device and process for recovering the regenerated tail gas of the triethylene glycol dehydration skid in the gas gathering station to overcome the above technical defects.

[0009] To solve the above technical problems, the present invention provides a device for recovering the regenerated tail gas of the triethylene glycol dehydration skid in the gas gathering station, which includes an emergency cut-off unit, a tail gas boosting unit, a tail gas cooling unit, and a tail gas separation unit connected in sequence through pipelines;

[0010] The gas phase separated by the tail gas separation unit goes to the flash gas recovery gas gathering system;

[0011] The liquid phase separated by the tail gas separation unit is pressurized and then discharged into the produced liquid buffer tank.

[0012] The emergency cut-off unit includes a first pipeline, on which a temperature transmitter for monitoring the temperature of the regenerated tail gas and a pressure transmitter for monitoring the pressure of the regenerated tail gas are installed;

[0013] An emergency cut-off valve is also installed on the first pipeline.

[0014] The tail gas boosting unit includes a second pipeline, and a Roots blower is installed on the second pipeline;

[0015] The first pipeline is connected and communicated with the second pipeline.

[0016] The tail gas cooling unit includes a third pipeline, and an air cooler is installed on the third pipeline;

[0017] The second pipeline is connected and communicated with the third pipeline.

[0018] The tail gas separation unit includes a separator;

[0019] The outlet of the air cooler is connected to the inlet of the separator through the third pipeline;

[0020] The gas outlet of the separator is connected with a fourth pipeline, and the fourth pipeline leads to the flash gas recovery gas collection system, and a vent branch is connected to the fourth pipeline;

[0021] The liquid outlet of the separator is connected with a fifth pipeline, and the fifth pipeline leads to the produced liquid buffer tank.

[0022] A liquid phase boosting unit is installed on the fifth pipeline. The liquid phase boosting unit includes a sewage pump installed on the fifth pipeline, and also includes a standby pipeline. One end of the standby pipeline is connected to the inlet side pipe of the sewage pump, and the other end of the standby pipeline is connected to the outlet side pipe of the sewage pump. A standby sewage pump is installed on the standby pipeline;

[0023] The liquid phases discharged by the sewage pump and the standby sewage pump are both discharged to the produced liquid buffer tank.

[0024] The regeneration tail gas recovery device of the triethylene glycol dehydration skid in the gas gathering station further includes a gas supplementing unit. The gas supplementing unit includes a sixth pipeline. One end of the sixth pipeline is connected to the pipeline between the tail gas boosting unit and the tail gas cooling unit, and the other end of the sixth pipeline is connected to the pipeline between the emergency cut-off unit and the tail gas boosting unit;

[0025] A gas supplementing regulating valve is installed on the sixth pipeline;

[0026] The regenerated tail gas boosted by the tail gas boosting unit flows through the gas supplementing regulating valve and is recycled to the inlet of the tail gas boosting unit.

[0027] The regeneration tail gas recovery device of the triethylene glycol dehydration skid in the gas gathering station further includes a circulating cooling unit. The circulating cooling unit includes a seventh pipeline, and a circulating water tank and a circulating water pump are installed on the seventh pipeline;

[0028] The cooling water in the seventh pipeline circulates and returns to cool the Roots blower.

[0029] The present invention also provides a regeneration tail gas recovery process for the triethylene glycol dehydration skid in the gas gathering station, which is applicable to the regeneration tail gas recovery device of the triethylene glycol dehydration skid in the gas gathering station. The regeneration tail gas recovery process includes:

[0030] The regeneration tail gas from the triethylene glycol dehydration skid of the gas gathering station enters the tail gas boosting unit through the emergency cut-off unit. The regeneration tail gas boosted by the tail gas boosting unit is cooled down by the tail gas cooling unit. The cooled regeneration tail gas enters the tail gas separation unit. The gas phase separated by the tail gas separation unit goes to the flash gas recovery gas gathering system, and the liquid phase separated by the tail gas separation unit is discharged to the produced liquid buffer tank after being boosted.

[0031] Before the regeneration tail gas enters the tail gas cooling unit, it specifically includes the following steps:

[0032] The emergency cut-off unit monitors the temperature and pressure of the regeneration tail gas. If the temperature of the regeneration tail gas is higher than 120°C or the pressure is lower than -10 KPa, the emergency cut-off valve in the emergency cut-off unit is closed. If the temperature of the regeneration tail gas is 95°C - 105°C and the pressure is -1 KPa - 2 KPa, the emergency cut-off valve is opened;

[0033] Detect the gas volume of the regeneration tail gas. If the gas volume of the regeneration tail gas is lower than 30 m 3 / h, the air make-up regulating valve on the air make-up unit is interlocked to open. The regeneration tail gas boosted by the Roots blower flows through the air make-up regulating valve and then returns to the Roots blower until the gas volume of the regeneration tail gas is higher than or equal to 30 m 3 / h.

[0034] The regeneration tail gas recovery device for the triethylene glycol dehydration skid of the gas gathering station proposed by the present invention is composed of an emergency cut-off unit, a tail gas boosting unit, a tail gas cooling unit, and a tail gas separation unit that are sequentially connected through pipelines. The whole process is hermetically connected through pipelines to ensure the airtightness of the entire gas gathering process. Compared with the traditional recovery method of using an incinerator to burn and convert it into the flash gas recovery gas gathering system, in the process of recovering the regeneration tail gas of the present invention, the separated gas phase goes to the flash gas recovery gas gathering system, effectively controlling the environmental pollution caused by the emission and combustion of the regeneration tail gas of the triethylene glycol dehydration skid. At the same time, there is a small amount of methane and alkanes in the tail gas, which can also play a role in energy conservation and emission reduction.

[0035] To make the above content of the present invention more obvious and understandable, the following specifically gives preferred embodiments and, in conjunction with the attached drawings, makes a detailed description as follows. Description of the Drawings

[0036] Figure 1 It is a process flow diagram of the existing regeneration tail gas treatment process for the triethylene glycol dehydration skid in the background technology.

[0037] Figure 2 It is a process flow diagram of the regeneration tail gas recovery process for the triethylene glycol dehydration skid of the gas gathering station proposed in this application.

[0038] Description of the Reference Numerals:

[0039] 10. Emergency cut-off unit;

[0040] 20. Tail gas supercharging unit; 21. Roots blower;

[0041] 30. Tail gas cooling unit;

[0042] 40. Tail gas separation unit;

[0043] 50. Liquid phase supercharging unit; 51. Sewage pump; 52. Standby sewage pump;

[0044] 60. Air supplement unit;

[0045] 70. Circulating cooling unit; 71. Circulating water tank; 72. Circulating water pump. Detailed implementation mode

[0046] The following specific embodiments illustrate the implementation mode of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0047] It should be noted that in the present invention, the up, down, left, and right in the figure are regarded as the up, down, left, and right of the regenerated tail gas recovery device of the triethylene glycol dehydration skid in the gas gathering station described in this specification.

[0048] Now refer to the accompanying drawings to introduce the exemplary implementation mode of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present invention in detail and completely, and to fully convey the scope of the present invention to those skilled in the relevant technical field. The terms in the exemplary implementation modes shown in the accompanying drawings are not limitations on the present invention. In the drawings, the same unit / element uses the same reference numeral.

[0049] Unless otherwise specified, the terms (including scientific and technical terms) used herein have the ordinary meaning understood by those skilled in the relevant technical field. In addition, it can be understood that the terms defined in the commonly used dictionary should be understood as having a meaning consistent with the context of their relevant fields, and should not be understood as idealized or overly formal meanings.

[0050] This implementation mode relates to a regenerated tail gas recovery device for a triethylene glycol dehydration skid in a gas gathering station. Please refer to Figure 2 , which includes an emergency cut-off unit 10, a tail gas supercharging unit 20, a tail gas cooling unit 30, and a tail gas separation unit 40 that are connected in sequence through pipelines.

[0051] The working process of the regenerated tail gas recovery device for the triethylene glycol dehydration skid in the gas gathering station is as follows:

[0052] The regeneration tail gas from the triethylene glycol dehydration skid of the gas gathering station enters the tail gas boosting unit 20 through the emergency cut-off unit 10. The regeneration tail gas boosted by the tail gas boosting unit 20 is cooled down by the tail gas cooling unit 30, and the cooled regeneration tail gas enters the tail gas separation unit 40 for gas-liquid separation.

[0053] The gas phase separated by the tail gas separation unit 40 goes to the flash gas recovery gas gathering system without combustion, and thus no SO 2 is generated, and no natural gas is consumed, which can effectively control the environmental pollution caused by the emission and combustion of the regeneration tail gas of the triethylene glycol dehydration skid; the liquid phase separated by the tail gas separation unit 40 is boosted and then discharged to the produced liquid buffer tank.

[0054] Continue to refer to Figure 1 the emergency cut-off unit 10 includes a first pipeline, on which a temperature transmitter for monitoring the temperature of the regeneration tail gas and a pressure transmitter for monitoring the pressure of the regeneration tail gas are installed, and an emergency cut-off valve is also installed on the first pipeline.

[0055] The temperature transmitter can monitor the temperature of the regeneration tail gas, and the pressure transmitter can monitor the pressure of the regeneration tail gas. If the temperature of the regeneration tail gas is higher than 120 °C or the pressure is lower than -10 KPa, the emergency cut-off valve is closed and the venting process is interlocked to open; if the temperature of the regeneration tail gas is 95 °C - 105 °C and the pressure is -1 KPa - 2 KPa, the emergency cut-off valve is opened.

[0056] Since the molar ratio of water vapor in the regeneration tail gas is 93%, and the waste gas volume is 25 m 3 / h - 127 m 3 / h, the temperature is 95 °C - 105 °C. If the gas phase flow rate after gas-liquid separation is 4 m 3 / h - 6 m 3 / h, and the minimum processing capacity of the current gas boosting facilities at home and abroad is 60 m 3 / h, then the equipment will not operate properly. Therefore, to meet the minimum allowable flow rate requirement of the boosting facilities, the pipeline between the emergency cut-off valve and the tail gas boosting unit 20 needs to be insulated to avoid as much as possible the temperature drop of the process pipeline resulting in gas-liquid separation and reducing the boosting gas volume.

[0057] The tail gas boosting unit 20 includes a second pipeline, on which a Roots blower 21 is installed, and the first pipeline is connected to the second pipeline.

[0058] The regeneration tail gas pressure is -1 KPa - 2 KPa, and the piston compressor does not have the negative pressure suction ability, so it cannot be applied. In addition, the regeneration tail gas temperature is 95 °C - 105 °C, and the required pressure boosting capacity is 100 KPa. The manufacturing cost of the screw compressor is relatively high and does not meet the requirements of improving quality and efficiency. Under the above requirements, according to the regeneration tail gas flow rate and the pressure boosting situation, a Roots blower is selected for the gas boosting facility.

[0059] As Figure 2 shown, the regeneration tail gas recovery device of the triethylene glycol dehydration skid in the gas gathering station further includes a gas supplementing unit 60. The gas supplementing unit 60 includes a sixth pipeline. One end of the sixth pipeline is connected to the pipeline between the tail gas boosting unit 20 and the tail gas cooling unit 30, and the other end of the sixth pipeline is connected to the pipeline between the emergency cut-off unit 10 and the tail gas boosting unit 20. A gas supplementing regulating valve is installed on the sixth pipeline. Specifically:

[0060] The regenerated tail gas boosted by the tail gas boosting unit 20 flows through the gas supplementing regulating valve and is returned to the inlet of the tail gas boosting unit 20. That is, the regenerated tail gas and the gas boosted by the boosted return gas are boosted to 0.06 MPa to 0.10 MPa. The main function of the boosted return gas is to supplement gas. When the amount of regenerated tail gas is less than 30 m 3 / h, the gas supplementing regulating valve is interlocked to open to ensure the continuous operation of the boosting facilities.

[0061] The gas supplementing unit 60 further includes a standby line. One end of the standby line is connected to the inlet side pipe of the gas supplementing regulating valve, and the other end is connected to the outlet side pipe of the gas supplementing regulating valve. A standby gas supplementing regulating valve is installed on the standby line. When the gas supplementing regulating valve needs to be overhauled, replaced, or repaired, the sixth pipeline can be closed and the standby gas supplementing regulating valve can be started to ensure the normal progress of the gas supplementing process.

[0062] To avoid that the gas volume after cooling and separation cannot meet the gas supplementing volume, the boosted return gas supplementing process (i.e., the gas supplementing unit 60) is arranged between the tail gas boosting unit 20 and the tail gas cooling unit 30.

[0063] The regeneration tail gas recovery device of the triethylene glycol dehydration skid in the gas gathering station further includes a circulating cooling unit 70. The circulating cooling unit 70 includes a seventh pipeline. A circulating water tank 71 and a circulating water pump 72 are installed on the seventh pipeline. The cooling water in the seventh pipeline circulates back to cool the roots blower 21. Specifically:

[0064] Since the temperature of the regenerated tail gas to be boosted is relatively high, in order to reduce the heat transfer from the gas cavity and rotor of the roots blower 21 to the mechanical seal, bearings, oil tank, etc., and ensure the reliable operation of the equipment, a cooling system is required to cool the bearings and lubricating oil tank of the roots blower 21. Therefore, the circulating cooling unit 70 is proposed. The circulating cooling unit 70 is composed of a circulating water pump 72, a circulating water tank 71, and corresponding pipelines, valves, etc. Among them, the inlet of the circulating water pump 72 is connected to the circulating water tank 71, the outlet of the circulating water pump 72 is connected to the roots blower 21 for cooling, and finally the coolant enters the circulating water tank 71 to complete a cooling cycle.

[0065] A bypass is also provided in the tail gas boosting unit 20 for purging during equipment commissioning or after commissioning and maintenance.

[0066] The tail gas cooling unit 30 includes a third pipeline, on which an air cooler is installed, and the second pipeline is connected to the third pipeline.

[0067] The pressurized regenerated tail gas is cooled to 15°C - 50°C by the air cooler. Due to the large variation in gas volume load and ambient temperature difference, the air cooler needs to apply variable frequency speed regulation.

[0068] The tail gas separation unit 40 includes a separator. The outlet of the air cooler is connected to the inlet of the separator through the third pipeline; the gas outlet of the separator is connected with a fourth pipeline, and the fourth pipeline leads to the flash gas recovery gas collection system, and a vent branch is connected to the fourth pipeline; the liquid outlet of the separator is connected with a fifth pipeline, and the fifth pipeline leads to the produced liquid buffer tank.

[0069] A liquid phase pressurization unit 50 is installed on the fifth pipeline. The liquid phase pressurization unit 50 includes a sewage pump 51 installed on the fifth pipeline, and also includes a standby pipeline. One end of the standby pipeline is connected to the inlet side pipe of the sewage pump 51, and the other end of the standby pipeline is connected to the outlet side pipe of the sewage pump 51. A standby sewage pump 52 is installed on the standby pipeline; the liquid phases discharged by the sewage pump 51 and the standby sewage pump 52 are both discharged to the produced liquid buffer tank.

[0070] The cooled gas-liquid mixture enters the separator for gas-liquid separation after being monitored for temperature and pressure. Among them, the gas phase conditions are gas volume Q: 4m 3 / h - 6m 3 / h, pressure P: 0.08 MPa, temperature T: 15°C - 50°C, and the medium components are mainly methane, hydrogen sulfide and alkanes, and finally it is connected to the inlet of the flash gas recovery device and pressurized to the gas collection system; the liquid phase is mainly a mixed solution of water and triethylene glycol. The liquid phase is pressurized to 0.2 MPa by the set sewage pump 51 and enters the produced water buffer tank, and finally is transported to the downstream treatment station through a pipeline. High and low liquid level interlocks with the start and stop of the sewage pump 51 are set in the separator. The high liquid level interlock starts the pump, and the low liquid level interlock stops the pump; the high-high liquid level interlock closes the emergency cut-off valve.

[0071] This embodiment also provides a process for recovering the regenerated tail gas of the triethylene glycol dehydration skid in the gas gathering station, which is applicable to the regenerated tail gas recovery device of the triethylene glycol dehydration skid in the gas gathering station. The regenerated tail gas recovery process includes:

[0072] (1) The regenerated tail gas from the triethylene glycol dehydration skid in the gas gathering station enters the tail gas pressurization unit 20 through the emergency cut-off unit 10. The emergency cut-off unit 10 monitors the temperature and pressure of the regenerated tail gas. If the temperature of the regenerated tail gas is higher than 120°C or the pressure is lower than -10 KPa, the emergency cut-off valve in the emergency cut-off unit 10 is closed. If the temperature of the regenerated tail gas is 95°C - 105°C and the pressure is -1 KPa - 2 KPa, the emergency cut-off valve is opened.

[0073] (2) Detect the gas volume of the regenerated tail gas. If the gas volume of the regenerated tail gas is less than 30m3 / h, the air make-up regulating valve on the air make-up unit 60 is interlocked and opened, and the regenerated tail gas pressurized by the Roots blower 21 flows back to the Roots blower 21 after passing through the air make-up regulating valve until the gas volume of the regenerated tail gas is higher than or equal to 30 m 3 / h.

[0074] (3) The regenerated tail gas pressurized by the tail gas pressurizing unit 20 is cooled down by the tail gas cooling unit 30.

[0075] (4) The cooled regenerated tail gas enters the tail gas separation unit 40. The gas phase separated by the tail gas separation unit 40 goes to the flash gas recovery and collection system, and the liquid phase separated by the tail gas separation unit 40 is pressurized and then discharged to the produced liquid buffer tank.

[0076] After applying the regenerated tail gas recovery process of the glycol dehydration skid in the gas gathering station provided in this embodiment to a certain gas gathering station, the relevant data is collected. Compared with the combustion of the tail gas incinerator and entering the venting system, the economic index comparison table is as follows:

[0077] Table 1 Comparison table of different process technologies and economic indexes of the regenerated tail gas of the glycol dehydration skid in a single gas gathering station

[0078]

[0079] Therefore, the application of the present invention can not only ensure that the gas field development meets the national environmental protection and technical index requirements, but also has the effects of cost reduction, efficiency increase, added value increase and energy conservation and emission reduction.

[0080] Those of ordinary skill in the art can understand that the above embodiments are specific embodiments for implementing the present invention, and in actual applications, various changes can be made in form and details without departing from the spirit and scope of the present invention.

Claims

1. The gas gathering station triethylene glycol dehydration skid regeneration tail gas recovery device is characterized by: It comprises an emergency cut-off unit (10), an exhaust gas pressurizing unit (20), an exhaust gas cooling unit (30), and an exhaust gas separation unit (40) which are sequentially connected through pipelines; The gas phase separated by the tail gas separation unit (40) is sent to a flash gas recovery gas collection system; The liquid phase separated by the tail gas separation unit (40) is pressurized and discharged to the produced liquid buffer tank.

2. The gas gathering station triethylene glycol dehydration skid regeneration tail gas recovery device according to claim 1, characterized in that: The emergency cutoff unit (10) comprises a first pipeline, on which a temperature transmitter for monitoring the temperature of the regenerated tail gas and a pressure transmitter for monitoring the pressure of the regenerated tail gas are installed; An emergency shut-off valve is also installed on the first pipeline.

3. The gas gathering station triethylene glycol dehydration skid regeneration tail gas recovery device according to claim 2, characterized in that: The exhaust gas boosting unit (20) comprises a second pipeline, on which a Roots blower (21) is installed; The first pipeline is communicated with the second pipeline.

4. The gas gathering station triethylene glycol dehydration skid regeneration tail gas recovery device according to claim 3, characterized in that: The tail gas cooling unit (30) comprises a third pipeline, and an air cooler is installed on the third pipeline; The second pipeline is communicated with the third pipeline.

5. The gas gathering station triethylene glycol dehydration skid regeneration tail gas recovery device according to claim 4, characterized in that: The tail gas separation unit (40) comprises a separator; The outlet of the air cooler is connected to the inlet of the separator through the third pipeline; The gas outlet of the separator is connected to a fourth pipeline, the fourth pipeline leads to the flash gas recovery gas collection system, and the fourth pipeline is connected to a venting branch; The liquid outlet of the separator is connected with a fifth pipeline, and the fifth pipeline leads to the produced liquid buffer tank.

6. The gas gathering station triethylene glycol dehydration skid regeneration tail gas recovery device according to claim 5, characterized in that: A liquid phase pressurizing unit (50) is installed on the fifth pipeline, the liquid phase pressurizing unit (50) comprises a sewage pump (51) installed on the fifth pipeline, and also comprises a spare pipeline, one end of the spare pipeline is connected to the inlet side pipe of the sewage pump (51), the other end of the spare pipeline is connected to the outlet side pipe of the sewage pump (51), and a spare sewage pump (52) is installed on the spare pipeline; The liquid phase discharged from the sewage pump (51) and the standby sewage pump (52) is discharged to the produced liquid buffer tank.

7. The gas gathering station triethylene glycol dehydration skid regeneration tail gas recovery device according to claim 3, characterized in that: The exhaust gas cooling unit (30) further comprises an air supply unit (60), wherein the air supply unit (60) comprises a sixth pipeline, one end of the sixth pipeline is connected to the pipeline between the exhaust gas supercharging unit (20) and the exhaust gas cooling unit (30), and the other end of the sixth pipeline is connected to the pipeline between the emergency cutoff unit (10) and the exhaust gas supercharging unit (20); An air supply regulating valve is installed on the sixth pipeline; The regenerated exhaust gas pressurized by the exhaust gas pressurizing unit (20) flows through the air supply regulating valve and is then fed back to the inlet of the exhaust gas pressurizing unit (20).

8. The gas gathering station triethylene glycol dehydration skid regeneration tail gas recovery device according to claim 3 or 7, characterized in that: It also includes a circulating cooling unit (70), the circulating cooling unit (70) including a seventh pipeline, on which a circulating water tank (71) and a circulating water pump (72) are installed; The cooling water in the seventh pipeline circulates back to cool the Roots blower (21).

9. The gas gathering station triethylene glycol dehydration skid regeneration tail gas recovery process is characterized by: The regeneration tail gas recovery device for triethylene glycol dehydration skid of a gas gathering station according to any one of claims 1 to 8, wherein the regeneration tail gas recovery process comprises: The regenerated tail gas from the triethylene glycol dehydration skid of the gas gathering station enters the tail gas boosting unit (20) through the emergency shutoff unit (10), the regenerated tail gas pressurized by the tail gas boosting unit (20) is cooled by the tail gas cooling unit (30), the cooled regenerated tail gas enters the tail gas separation unit (40), the gas phase separated by the tail gas separation unit (40) is sent to the flash gas recovery gas collection system, and the liquid phase separated by the tail gas separation unit (40) is discharged to the produced liquid buffer tank after being pressurized.

10. The gas gathering station triethylene glycol dehydration skid regeneration tail gas recovery process according to claim 9, characterized in that: Before the regenerated tail gas enters the tail gas cooling unit (30), the following steps are specifically included: The emergency cut-off unit (10) monitors the temperature and pressure of the regenerated tail gas. If the temperature of the regenerated tail gas is higher than 120° C. or the pressure is lower than -10 KPa, the emergency cut-off valve in the emergency cut-off unit (10) is closed. If the temperature of the regenerated tail gas is between 95° C. and 105° C. and the pressure is between -1 KPa and 2 KPa, the emergency cut-off valve is opened. Detect the volume of the regenerated tail gas. If the volume of the regenerated tail gas is less than 30m 3 / h, the air supply regulating valve on the air supply unit (60) is interlocked and opened, and the regenerated exhaust gas pressurized by the Roots blower (21) flows through the air supply regulating valve and then flows back to the Roots blower (21) until the amount of the regenerated exhaust gas is greater than or equal to 30m 3 / h.

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