Natural gas deacidification device and natural gas deacidification process

Abstract

The application discloses a natural gas deacidification device and a natural gas deacidification process, and relates to the field of natural gas purification; the device comprises a tower type skid and a horizontal type module; the tower type skid is provided with upper halves of a plurality of absorption towers and upper halves of a plurality of regeneration towers; the horizontal type skid is provided with lower halves of the plurality of absorption towers and lower halves of the plurality of regeneration towers; the tower type skid can be fixed on the horizontal type skid to form a plurality of absorption towers connected in series and a plurality of regeneration towers connected in series; the regeneration towers are connected with the absorption towers through pipelines; the absorption towers can be contacted with natural gas by spraying lean amine solution to realize deacidification of the natural gas; the regeneration towers can transport the lean amine solution into the absorption towers, and after the rich amine solution formed after participating in the deacidification is regenerated into the lean amine solution, the lean amine solution is transported into the absorption towers again. The application can ensure the deacidification effect of the natural gas, and is convenient for transportation and installation.

Description

Technical Field

[0001] This invention relates to the field of natural gas purification technology, and in particular to a natural gas deacidification device and a natural gas deacidification process. Background Technology

[0002] The core function of a natural gas deacidification unit is to remove acidic components, mainly carbon dioxide and hydrogen sulfide, from the natural gas feedstock, preventing these components from condensing, clogging, and corroding valves, pipelines, and other equipment during subsequent liquefaction. Traditional natural gas deacidification units use large deacidification absorption towers and amine regeneration towers, typically 30-50 meters high. This height exceeds the limit, making transportation difficult and on-site installation challenging; conversely, smaller sizes cannot achieve the desired natural gas deacidification effect.

[0003] Therefore, there is an urgent need to design a technical solution that can ensure the effectiveness of natural gas deacidification while facilitating transportation and installation. Summary of the Invention

[0004] The purpose of this invention is to provide a natural gas deacidification device and a natural gas deacidification process to solve the problems existing in the prior art, which can ensure the natural gas deacidification effect while facilitating transportation and installation.

[0005] To achieve the above objectives, the present invention provides the following solution: This invention provides a natural gas deacidification device, comprising: A tower-type skid block, which has the upper half of multiple absorption towers and the upper half of multiple regeneration towers; A horizontal skid has a lower half of multiple absorption towers and a lower half of multiple regeneration towers; the tower skid can be fixedly mounted on the horizontal skid so that the upper half of the absorption tower can be fixedly and sealedly connected with the lower half of the corresponding absorption tower to form multiple absorption towers connected in series, and the upper half of the regeneration tower can be fixedly and sealedly connected with the lower half of the corresponding regeneration tower to form multiple regeneration towers connected in series. The regeneration tower and the absorption tower are connected by pipelines. The absorption tower can use sprayed amine lean liquid to contact natural gas to achieve acid removal from natural gas. The regeneration tower can transport amine lean liquid into the absorption tower and regenerate the amine rich liquid formed after acid removal in the absorption tower into amine lean liquid, which is then transported back into the absorption tower.

[0006] Preferably, the absorption tower includes a first absorption tower and a second absorption tower, the upper halves of the first and second absorption towers are fixedly installed inside the tower skid, and the lower halves of the first and second absorption towers are fixedly installed inside the horizontal skid; the bottom of the first absorption tower is provided with a natural gas inlet, and the top of the first absorption tower is connected to the bottom of the second absorption tower through a natural gas pipeline; the top of the second absorption tower is externally connected to a post-treatment device through a natural gas pipeline; both the top of the first and second absorption towers are provided with a spraying device, which is used to spray the lean amine solution.

[0007] Preferably, the regeneration tower includes a first regeneration tower and a second regeneration tower. The upper halves of the first and second regeneration towers are respectively fixed inside the tower skid, and the lower halves of the first and second regeneration towers are respectively fixed inside the horizontal skid. The top of the second regeneration tower is connected to the bottom of the first and second absorption towers respectively through a rich amine solution pipeline, and the bottom of the second regeneration tower is connected to the top of the first regeneration tower through an amine solution pipeline. A regeneration tower delivery pump is provided on the amine solution pipeline between the second and first regeneration towers. The bottom of the first regeneration tower is connected to the spray devices of the first and second absorption towers respectively through a lean amine solution pipeline. A lean solution pump and a lean solution cooler are sequentially provided on the lean amine solution pipeline.

[0008] Preferably, the post-processing equipment includes a natural gas cooler and a natural gas separator fixedly installed in the horizontal skid. The top of the second absorption tower is connected in series with the natural gas cooler and the natural gas separator via a natural gas pipeline. The output end of the natural gas separator is used to connect to a dehydration device.

[0009] Preferably, the horizontal skid is equipped with a lean-rich liquid heat exchanger, and both the amine rich liquid pipeline and the amine lean liquid pipeline flow through the lean-rich liquid heat exchanger, so that the amine rich liquid in the amine rich liquid pipeline and the amine lean liquid in the amine lean liquid pipeline can exchange heat in the lean-rich liquid heat exchanger.

[0010] Preferably, a reboiler is connected to one side of the first regeneration tower and the other side of the second regeneration tower. The amine-rich liquid in the first regeneration tower is heated in the reboiler and then circulated back into the first regeneration tower to form an amine-poor liquid. The amine-rich liquid in the second regeneration tower is heated in the reboiler and then circulated back into the second regeneration tower to form an amine-poor liquid.

[0011] Preferably, both the first regeneration tower and the second regeneration tower are equipped with acid gas pipelines, which are connected to a main acid gas pipeline. The main acid gas pipeline is sequentially connected to an acid gas cooler, an acid gas separator, and a sulfur recovery unit. The acid gas separator is connected to the first regeneration tower and the second regeneration tower respectively through a liquid phase pipeline. The liquid phase pipeline is equipped with a regeneration tower reflux pump, which can pressurize the liquid phase separated in the acid gas separator and return it to the second regeneration tower.

[0012] Preferably, the lean solution pump is connected to an activated carbon adsorber pipeline and a dosing device pipeline, which can defoam, adsorb, and filter the amine solution. Both the activated carbon adsorber pipeline and the dosing device pipeline are equipped with solenoid valves.

[0013] Preferably, the lean liquid cooler is connected to an underground amine liquid tank via a replenishment pipeline equipped with a solenoid valve, the underground amine liquid tank being used to store amine liquid.

[0014] The present invention also provides a natural gas deacidification process based on the above-mentioned natural gas deacidification device, comprising the following steps: The natural gas feedstock flows sequentially through the first and second absorption towers and comes into countercurrent contact with the sprayed amine lean liquid. The natural gas discharged from the second absorption tower is cooled down by the natural gas cooler and then enters the natural gas separator for gas-liquid separation, and then enters the dehydration equipment for dehydration process. The rich amine solution discharged from the first and second absorption towers enters the lean-rich solution heat exchanger to exchange heat with the lean solution discharged from the first regeneration tower and is heated. Then it flows through the second and first regeneration towers in sequence for stripping regeneration. The regenerated lean solution is cooled by exchanging heat with the rich solution in the lean-rich solution heat exchanger and is then transported to the spraying device for spraying. During the regeneration process of the lean amine solution in the first and second regeneration towers, the acidic gas sequentially enters the acid gas cooler for cooling and the acid gas separator for gas-liquid separation before entering the subsequent sulfur recovery unit. The liquid phase in the acid gas separator is pressurized by the regeneration tower reflux pump and returned to the second regeneration tower.

[0015] The present invention achieves the following technical effects compared to the prior art: This invention separates the integrated absorption tower and integrated regeneration tower into two absorption towers and two regeneration towers connected in series, respectively. While maintaining performance, this reduces the size and height of the equipment, lowers production and processing difficulty, facilitates transportation and on-site installation, and streamlines later maintenance and adjustments. The absorption tower and regeneration tower are further divided into upper and lower sections, and upper and lower sections, respectively, which are skid-mounted within tower-type and horizontal skids, further reducing the size and height of the equipment. The entire device consists of two skids: a tower-type skid and a horizontal skid. This reduces the overall height while maintaining performance, significantly reduces transportation limitations for each skid, facilitates transport, makes on-site installation more convenient, and adapts to complex site conditions. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of a natural gas deacidification device in one or more embodiments of the present invention; Figure 2 This is a schematic diagram of the tower skid structure of a natural gas deacidification device in one or more embodiments of the present invention. Figure 3 This is a schematic diagram of a horizontal skid structure of a natural gas deacidification device in one or more embodiments of the present invention. Figure 4 This is a schematic diagram of the natural gas feedstock deacidification process of the natural gas deacidification process of the present invention; Figure 5 This is a schematic diagram of the amine liquid regeneration process of the natural gas deacidification process of the present invention.

[0018] In the diagram: 1-First absorption tower, 2-Second absorption tower, 3-First regeneration tower, 4-Second regeneration tower, 5-Acid gas cooler, 6-Acid gas separator, 7-Activated carbon adsorber, 8-Dosing device, 9-Lean solution cooler, 10-Reboiler, 11-Lean and rich solution heat exchanger, 12-Lean solution pump, 13-Regeneration tower delivery pump, 14-Regeneration tower reflux pump, 15-Natural gas cooler, 16-Natural gas separator. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] The purpose of this invention is to provide a natural gas deacidification device and a natural gas deacidification process to solve the problems existing in the prior art, which can ensure the natural gas deacidification effect while facilitating transportation and installation.

[0021] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] Existing natural gas deacidification units utilize large-sized deacidification absorption towers and amine regeneration towers, exceeding height limits and posing challenges for transportation and on-site installation. Conversely, smaller towers fail to achieve the desired deacidification effect. Therefore, simply reducing the size of the absorption and regeneration towers is insufficient to solve this problem. To ensure effective deacidification while facilitating transportation and installation, this invention provides a natural gas deacidification device, as described in the reference. Figure 1 , Figure 2 , Figure 3As shown, the system includes a tower-type skid and a horizontal skid. The tower-type skid has upper halves of multiple absorption towers and upper halves of multiple regeneration towers; the horizontal skid has lower halves of multiple absorption towers and lower halves of multiple regeneration towers. The tower-type skid can be fixedly mounted on the horizontal skid, so that the upper halves of the absorption towers can be fixedly and sealed to the corresponding lower halves of the absorption towers by threaded connection or by snap-fit ​​with sealing rings to form multiple absorption towers connected in series. The upper halves of the regeneration towers can be fixedly and sealed to the corresponding lower halves of the regeneration towers by threaded connection or by snap-fit ​​with sealing rings to form multiple regeneration towers connected in series. The regeneration towers and absorption towers are connected by pipelines. The absorption towers can use sprayed amine lean solution to contact natural gas to achieve acid removal from the natural gas. The regeneration towers can supply amine lean solution to the absorption towers and regenerate the amine rich solution formed after acid removal in the absorption towers into amine lean solution, which is then resupplyed to the absorption towers. This invention separates the integrated absorption tower and integrated regeneration tower into two absorption towers and two regeneration towers connected in series, respectively. While maintaining performance, this reduces the size and height of the equipment, lowers production and processing difficulty, facilitates transportation and on-site installation, and streamlines later maintenance and adjustments. The absorption tower and regeneration tower are further divided into upper and lower sections, and upper and lower sections, respectively, which are skid-mounted within tower-type and horizontal skids, further reducing the size and height of the equipment. The entire device consists of two skids: a tower-type skid and a horizontal skid. This reduces the overall height while maintaining performance, significantly reduces transportation limitations for each skid, facilitates transport, makes on-site installation more convenient, and adapts to complex site conditions.

[0023] In one embodiment, the absorption tower includes a first absorption tower 1 and a second absorption tower 2. The upper halves of the first absorption tower 1 and the second absorption tower 2 are fixedly installed inside a tower skid, and the lower halves of the first absorption tower 1 and the second absorption tower 2 are fixedly installed inside a horizontal skid. The bottom of the first absorption tower 1 is provided with a natural gas inlet, and the top of the first absorption tower 1 is connected to the bottom of the second absorption tower 2 through a natural gas pipeline. The top of the second absorption tower 2 is externally connected to a post-processing device through a natural gas pipeline. Both the top of the first absorption tower 1 and the top of the second absorption tower 2 are provided with a spraying device, which is used to spray the lean amine solution. The regeneration tower in this embodiment includes a first regeneration tower 3 and a second regeneration tower 4. The upper halves of the first regeneration tower 3 and the second regeneration tower 4 are fixedly installed in tower-type skids, and the lower halves of the first regeneration tower 3 and the second regeneration tower 4 are fixedly installed in horizontal skids. The top of the second regeneration tower 4 is connected to the bottom of the first absorption tower 1 and the second absorption tower 2 respectively through a rich amine liquid pipeline, and the bottom of the second regeneration tower 4 is connected to the top of the first regeneration tower 3 through an amine liquid pipeline. A regeneration tower delivery pump 13 is provided on the amine liquid pipeline between the second regeneration tower 4 and the first regeneration tower 3. The bottom of the first regeneration tower 3 is connected to the spray devices of the first absorption tower 1 and the second absorption tower 2 respectively through a lean amine liquid pipeline. A lean liquid pump 12 and a lean liquid cooler 9 are sequentially provided on the lean amine liquid pipeline.

[0024] In one embodiment, the post-processing equipment includes a natural gas cooler 15 and a natural gas separator 16 fixedly installed within a horizontal skid. The top of the second absorption tower 2 is sequentially connected to the natural gas cooler 15 and the natural gas separator 16 via a natural gas pipeline. The output end of the natural gas separator 16 is used to connect to a dehydration device. A lean-rich liquid heat exchanger 11 is installed within the horizontal skid. Both the rich amine liquid pipeline and the lean amine liquid pipeline flow through the lean-rich liquid heat exchanger 11, allowing heat exchange between the rich amine liquid in the rich amine liquid pipeline and the lean amine liquid in the lean amine liquid pipeline within the lean-rich liquid heat exchanger 11. Figure 5 As shown, a reboiler 10 is connected to one side of the first regeneration tower 3. After the amine-rich liquid in the first regeneration tower 3 is heated in the reboiler 10, it is circulated back into the first regeneration tower 3 to form an amine-lean liquid. A reboiler 10 is connected to one side of the second regeneration tower 4. After the amine-rich liquid in the second regeneration tower 4 is heated in the reboiler 10, it is circulated back into the second regeneration tower 4 to form an amine-lean liquid.

[0025] In one embodiment, both the first regeneration tower 3 and the second regeneration tower 4 are equipped with acidic gas pipelines. The acidic gas pipelines of the first regeneration tower 3 and the second regeneration tower 4 converge and connect to an acidic gas main pipe. The acidic gas main pipe is sequentially connected to an acidic gas cooler 5, an acidic gas separator 6, and a sulfur recovery unit. The acidic gas separator 6 is connected to both the first regeneration tower 3 and the second regeneration tower 4 via a liquid phase pipeline. A regeneration tower reflux pump 14 is installed on the liquid phase pipeline, which pressurizes the liquid phase separated in the acidic gas separator 6 and returns it to the second regeneration tower 4. A lean liquid pump 12 is connected to an activated carbon adsorber 7 pipeline and a dosing device 8 pipeline, which can perform defoaming adsorption filtration on the amine solution. Both the activated carbon adsorber 7 pipeline and the dosing device 8 pipeline are equipped with solenoid valves. The activated carbon adsorber 7 pipeline is used to remove heavy hydrocarbons, other liquid contaminants, and dissolved solids from the lean liquid. The dosing device 8 pipeline is used to add defoamer, effectively reducing the surface tension of the liquid and reducing foaming loss of the amine solution. The lean liquid cooler 9 is connected to an underground amine liquid tank via a replenishment pipeline equipped with a solenoid valve. The underground amine liquid tank is used to store amine liquid.

[0026] This invention incorporates various online analyzers, including online hydrogen sulfide and carbon dioxide detectors, into its pipelines and equipment, enabling online monitoring of various natural gas parameters and providing timely early warning information. Furthermore, it adds online metering instruments to the traditional natural gas processing system, allowing for monitoring of parameters such as gas pressure and flow rate without the need for on-site sampling.

[0027] The present invention also provides a natural gas desulfurization process based on the above-mentioned natural gas desulfurization device, with reference to Figure 4 and Figure 5 As shown, it includes the following steps: Natural gas feedstock acid removal process: Natural gas feedstock enters from the bottom of the first absorption tower 1 and flows from bottom to top through the first absorption tower 1, where it comes into countercurrent contact with the MDEA lean liquid sprayed from the top of the tower. The MDEA lean liquid is an amine lean liquid, which absorbs acidic gases such as CO2 and H2S in the gas. The treated natural gas is drawn out from the top of the first absorption tower 1 and enters the bottom of the second absorption tower 2. After being absorbed and deacidified again by the MDEA lean liquid, it is drawn out from the top of the second absorption tower 2. After being cooled by the natural gas cooler 15, it enters the natural gas separator 16 for gas-liquid separation, and then enters the existing dehydration equipment for dehydration. Both the dehydration equipment and the dehydration process are mature existing technologies.

[0028] Amine liquid regeneration process: After the MDEA lean liquid sprayed at the top of the absorber comes into contact with natural gas, the CO2 and H2S content increases, turning it into MDEA rich liquid. The MDEA rich liquid is also known as amine rich liquid. It is discharged from the bottom of the absorber and enters the lean-rich liquid heat exchanger 11 to exchange heat with the higher-temperature lean liquid and is heated to 96°C before entering the second regeneration tower 4 for stripping regeneration. After being collected at the bottom of the second regeneration tower 4, it is then pressurized by the regeneration tower delivery pump 13 and sent to the first regeneration tower 3 for stripping regeneration again. At the same time, the reboiler 10 heated by heat transfer oil raises the temperature of the amine rich liquid to 114°C to generate amine vapor. The acidic gas in the amine liquid is desorbed, and the amine liquid is circulated and regenerated until it is converted into amine lean liquid. The regenerated amine lean liquid flows out from the bottom of the first regeneration tower 3 and is cooled by exchanging heat with the lower-temperature amine rich liquid through the lean-rich liquid heat exchanger 11. After being pressurized by the lean liquid pump 12, the amine lean liquid is cooled to the required temperature by the lean liquid cooler 9 and returned to the first absorber tower 1 and the second absorber tower 2. The acidic gas exiting from the top of the first regeneration tower 3 and the second regeneration tower 4 carries a small amount of amine liquid. This gas enters the acid gas cooler 5 for cooling and the acid gas separator 6 for gas-liquid separation before entering the subsequent sulfur recovery unit, which is a mature, existing technology. The liquid phase in the acid gas separator 6 is pressurized by the regeneration tower reflux pump 14 and returned to the second regeneration tower 4. Figure 5 The red line represents the flow path of the lean amine solution, and the blue line represents the flow path of the rich amine solution. Amine solutions lost during operation are replenished by drawing amine solutions from the underground amine tank using a replenishment pump. The replenished amine solution is prepared by mixing amine solutions from the underground amine tank with demineralized water.

[0029] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A natural gas deacidification device, characterized in that: include: A tower-type skid block, which has the upper half of multiple absorption towers and the upper half of multiple regeneration towers; A horizontal skid block having the lower half of multiple absorption towers and the lower half of multiple regeneration towers; The tower-type skid can be fixedly mounted on the horizontal skid so that the upper half of the absorption tower can be fixedly and sealedly connected with the lower half of the corresponding absorption tower to form multiple absorption towers connected in series. The upper half of the regeneration tower can be fixedly and sealedly connected with the lower half of the corresponding regeneration tower to form multiple regeneration towers connected in series. The regeneration tower and the absorption tower are connected by pipelines. The absorption tower can use sprayed amine lean liquid to contact natural gas to achieve acid removal from natural gas. The regeneration tower can transport amine lean liquid into the absorption tower and regenerate the amine rich liquid formed after acid removal in the absorption tower into amine lean liquid, which is then transported back into the absorption tower. The absorption tower includes a first absorption tower and a second absorption tower. The upper halves of the first and second absorption towers are fixedly installed within the tower-type skid, and the lower halves of the first and second absorption towers are fixedly installed within the horizontal skid. The regeneration tower includes a first regeneration tower and a second regeneration tower. The upper halves of the first and second regeneration towers are respectively fixedly installed within the tower-type skid, and the lower halves of the first and second regeneration towers are respectively fixedly installed within the horizontal skid. The bottom of the first absorption tower is provided with a natural gas inlet, and the top of the first absorption tower is connected to the horizontal skid via a natural gas pipeline. The bottom of the second absorption tower is connected; the top of the second absorption tower is connected to a post-processing device via a natural gas pipeline; the post-processing device includes a natural gas cooler and a natural gas separator fixedly installed inside the horizontal skid; the top of the second regeneration tower is connected to the bottom of the first and second absorption towers respectively via a rich amine liquid pipeline; the bottom of the first regeneration tower is connected to the spray devices of the first and second absorption towers respectively via a lean amine liquid pipeline; a rich-lean-lean liquid heat exchanger is provided inside the horizontal skid, and both the rich amine liquid pipeline and the lean amine liquid pipeline flow through the rich-lean-lean liquid heat exchanger.

2. The natural gas deacidification device according to claim 1, characterized in that: Both the top of the first absorption tower and the top of the second absorption tower are equipped with spraying devices, which are used to spray the amine solution (in lean form).

3. The natural gas deacidification device according to claim 2, characterized in that: The bottom of the second regeneration tower is connected to the top of the first regeneration tower via an amine liquid pipeline. A regeneration tower delivery pump is installed on the amine liquid pipeline between the second regeneration tower and the first regeneration tower. A lean liquid pump and a lean liquid cooler are sequentially installed on the lean liquid pipeline.

4. The natural gas deacidification device according to claim 2, characterized in that: The top of the second absorption tower is connected in series with the natural gas cooler and the natural gas separator via a natural gas pipeline, and the output end of the natural gas separator is used to connect to a dehydration device.

5. The natural gas deacidification device according to claim 3, characterized in that: The rich amine solution in the rich amine solution pipeline and the lean amine solution in the lean amine solution pipeline can exchange heat in the rich and lean solution heat exchanger.

6. The natural gas deacidification device according to claim 3, characterized in that: Both the first regeneration tower and the second regeneration tower are connected to reboilers. The amine-rich liquid in the first regeneration tower is heated in the reboiler and then circulated back into the first regeneration tower to form an amine-poor liquid. The amine-rich liquid in the second regeneration tower is heated in the reboiler and then circulated back into the second regeneration tower to form an amine-poor liquid.

7. The natural gas deacidification device according to claim 3, characterized in that: Both the first regeneration tower and the second regeneration tower are equipped with acid gas pipelines. The acid gas pipelines of the first regeneration tower and the second regeneration tower are both connected to the acid gas main pipe. The acid gas main pipe is sequentially connected to an acid gas cooler, an acid gas separator, and a sulfur recovery unit. The acid gas separator is connected to the first regeneration tower and the second regeneration tower respectively through a liquid phase pipeline. The liquid phase pipeline is equipped with a regeneration tower reflux pump, which can pressurize the liquid phase separated in the acid gas separator and return it to the second regeneration tower.

8. The natural gas deacidification device according to claim 3, characterized in that: The lean solution pump is connected to an activated carbon adsorber pipeline and a dosing device pipeline, which can defoam, adsorb, and filter the amine solution. Both the activated carbon adsorber pipeline and the dosing device pipeline are equipped with solenoid valves.

9. The natural gas deacidification device according to claim 3, characterized in that: The lean liquid cooler is connected to an underground amine liquid tank via a replenishment pipeline equipped with a solenoid valve. The underground amine liquid tank is used to store amine liquid.

10. A natural gas desulfurization process based on the natural gas desulfurization device according to any one of claims 1 to 9, characterized in that: Includes the following steps: The natural gas feedstock flows sequentially through the first and second absorption towers and comes into countercurrent contact with the sprayed amine lean liquid. The natural gas discharged from the second absorption tower is cooled down by the natural gas cooler and then enters the natural gas separator for gas-liquid separation, and then enters the dehydration equipment for dehydration process. The rich amine solution discharged from the first and second absorption towers enters the lean-rich solution heat exchanger to exchange heat with the lean solution discharged from the first regeneration tower and is heated. Then it flows through the second and first regeneration towers in sequence for stripping regeneration. The regenerated lean solution is cooled by exchanging heat with the rich solution in the lean-rich solution heat exchanger and is then transported to the spraying device for spraying. During the regeneration process of the lean amine solution in the first and second regeneration towers, the acidic gas sequentially enters the acid gas cooler for cooling and the acid gas separator for gas-liquid separation before entering the subsequent sulfur recovery unit. The liquid phase in the acid gas separator is pressurized by the regeneration tower reflux pump and returned to the second regeneration tower.

Images