A sour gas classification absorption tower

Abstract

The utility model discloses a kind of acid gas classification suction type absorption towers, belong to desulfurization equipment technical field, it includes tower body and inclined partition, inclined partition separates tower body into two cavities, the cavity above inclined partition in tower body is carbon dioxide absorption cavity, the cavity below inclined partition in tower body is hydrogen sulfide absorption cavity, plate type microchannel unit is equipped in hydrogen sulfide absorption cavity and located above the inlet of gas to be treated gas, and desulfurization gas outlet is equipped on the lateral wall of hydrogen sulfide absorption cavity, desulfurization gas inlet is equipped on the lateral wall of carbon dioxide absorption cavity, desulfurization gas inlet is communicated with the desulfurization gas outlet by desulfurization gas pipe, and baffle type staggered plate group is equipped in carbon dioxide absorption cavity and located above desulfurization gas inlet.The application improves acid gas classification suction type absorption tower, realizes acid gas classification suction type classification processing, solves the problem that CO2 co-absorption in amine method desulfurization causes acid gas H2S concentration low.

Description

Technical Field

[0001] This utility model relates to the technical field of desulfurization equipment for natural gas, syngas and refinery gas, specifically an acid gas classification and absorption tower. Background Technology

[0002] Amine-based H2S removal technology is widely used in the desulfurization processes of natural gas, syngas, and refinery gas. However, amine-based desulfurizing agents absorb CO2 from the process gas along with H2S, leading to a decrease in the H2S concentration in the regenerated acid gas. The high CO2 content in the acid gas makes subsequent sulfur recovery processes difficult to operate and increases investment. For units with a low H2S / CO2 ratio in the process gas, a two-stage absorption-two-stage regeneration process must be used to ensure that the H2S concentration in the regenerated acid gas meets the CLAUS (Clearance of Intake) requirement, or a large amount of fuel gas must be used for co-firing to ensure the thermal balance of the sulfur production unit. Therefore, existing amine-based H2S removal equipment needs to be improved to meet energy-saving and environmental protection requirements. Utility Model Content

[0003] The purpose of this invention is to provide an acid gas classification and absorption tower that improves the H2S regeneration concentration in acid gas.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: A gas separation and absorption tower for acid gases includes a tower body and an inclined partition plate. The inclined partition plate is located inside the tower body and divides the tower body into upper and lower cavities. The cavity above the inclined partition plate is a carbon dioxide absorption cavity, and the cavity below the inclined partition plate is a hydrogen sulfide absorption cavity. The top of the tower body has a treated gas outlet, and the bottom of the tower body has a hydrogen sulfide-rich liquid outlet. The side wall of the hydrogen sulfide absorption cavity has a gas inlet for untreated gases. A plate-type microchannel unit is located inside the hydrogen sulfide absorption cavity and above the gas inlet for untreated gases. A plate-type microchannel unit is located on the side wall of the hydrogen sulfide absorption cavity and above the plate-type microchannel unit. A hydrogen sulfide absorbent inlet is provided; a desulfurization gas outlet is provided on the side wall of the hydrogen sulfide absorption chamber at the highest point of the inclined partition plate; a carbon dioxide rich liquid outlet is provided on the side wall of the carbon dioxide absorption chamber at the lowest point of the inclined partition plate; a desulfurization gas inlet is provided on the side wall of the carbon dioxide absorption chamber above the carbon dioxide rich liquid outlet, and the desulfurization gas inlet is connected to the desulfurization gas outlet through a desulfurization gas conduit; a baffle-type staggered plate assembly is provided inside the carbon dioxide absorption chamber above the desulfurization gas inlet; and a carbon dioxide absorbent inlet is provided on the side wall of the carbon dioxide absorption chamber above the baffle-type staggered plate assembly.

[0005] Furthermore, a gas-liquid separation hydrophilic membrane is provided inside the hydrogen sulfide absorption chamber and near the hydrogen sulfide rich liquid outlet. The gas-liquid separation hydrophilic membrane is used to block gas and allow the hydrogen sulfide rich liquid to pass through the gas-liquid separation hydrophilic membrane.

[0006] Furthermore, a gas-liquid separation hydrophobic membrane is provided inside the carbon dioxide absorption chamber and above the carbon dioxide absorbent, and the gas-liquid separation hydrophobic membrane is located below the treated gas outlet.

[0007] Furthermore, the plate-type microchannel unit adopts a pull-out modular plate-type microchannel. The tower body has a pull-out opening on its side wall, and the tower body is equipped with load-bearing guide rails on both sides of the pull-out opening. The pull-out modular plate-type microchannel extends from the pull-out opening and is supported on the load-bearing guide rails.

[0008] Furthermore, the plate-type microchannel unit includes a square frame and multiple corrosion-resistant plates, which are stacked side-by-side in the square frame. Each corrosion-resistant plate has a row of vertical microchannels on its surface, and protrusions are distributed on the inner wall of each vertical microchannel. These protrusions disrupt the gas-liquid boundary layer, increasing turbulence and thus improving the mass transfer coefficient.

[0009] Furthermore, the outer side of the square frame is provided with a pull-out handle, and the bottom of both sides of the square frame is provided with rollers, which are supported on the support rail and can roll along the support rail.

[0010] Furthermore, the corrosion-resistant plate is made of silicon carbide ceramic or PTFE material; the vertical microchannel has a diameter of 50-300μm and a length of 4-6cm.

[0011] Furthermore, the gas-liquid separation hydrophobic membrane is a pull-out modular gas-liquid separation hydrophobic membrane, and the gas-liquid separation hydrophilic membrane is a pull-out modular gas-liquid separation hydrophilic membrane. The tower body has an upper pull-out port and a lower pull-out port on its side wall. The tower body has upper support guide rails on both sides of the upper pull-out port and lower support guide rails on both sides of the lower pull-out port. The pull-out modular gas-liquid separation hydrophobic membrane extends from the upper pull-out port and is supported on the upper support guide rail, and the pull-out modular gas-liquid separation hydrophilic membrane extends from the lower pull-out port and is supported on the lower support guide rail.

[0012] Furthermore, the gas-liquid separation hydrophobic membrane includes a hydrophobic membrane body made of PTFE material, and membrane pores distributed on the surface of the hydrophobic membrane body, with an inner diameter of 0.15-0.35 μm; the gas-liquid separation hydrophilic membrane includes a hydrophilic membrane body made of PVDF material, and membrane pores distributed on the surface of the hydrophilic membrane body, with an inner diameter of 0.55-0.65 μm.

[0013] The beneficial effects of this utility model are as follows: This application improves the acid gas classification and absorption tower, realizing the classification and treatment of acid gas, and solving the problem of low H2S concentration in acid gas caused by CO2 co-absorption in amine desulfurization. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 for Figure 1 The side view shown; Figure 3 for Figure 1 The diagram shows the structure of the plate-type microchannel unit. Figure 4 for Figure 3 The diagram shows the structure of the corrosion-resistant plate.

[0015] In the diagram: 1. Tower body; 2. Inclined partition plate; 3. Carbon dioxide absorption chamber; 4. Hydrogen sulfide absorption chamber; 5. Treated gas outlet; 6. Hydrogen sulfide rich liquid outlet; 7. Gas-liquid separation hydrophilic membrane; 8. Gas to be treated outlet; 9. Plate-type microchannel unit; 10. Hydrogen sulfide absorbent outlet; 11. Desulfurized gas outlet; 12. Carbon dioxide rich liquid outlet; 13. Desulfurized gas inlet; 14. Desulfurized gas conduit; 15. Baffle-type staggered plate assembly; 16. Carbon dioxide absorbent outlet; 17. Gas-liquid separation hydrophobic membrane; 18. Upper pull-out port; 19. Lower pull-out port; 20. Upper support guide rail; 21. Lower support guide rail; 22. Pull-out port; 23. Support guide rail; 24. Square frame; 25. Corrosion-resistant plate; 26. Vertical microchannel; 27. Protrusion; 28. Pull-out handle; 29. ​​Roller. Detailed Implementation

[0016] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0017] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper surface", "lower surface", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "forward", "reverse", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0018] like Figure 1 , Figure 2 As shown, an acid gas separation and absorption tower includes a tower body 1 and an inclined partition plate 2. The inclined partition plate 2 is located inside the tower body 1 and divides the tower body 1 into upper and lower cavities. The cavity above the inclined partition plate 2 inside the tower body 1 is a carbon dioxide absorption cavity 3, and the cavity below the inclined partition plate 2 inside the tower body is a hydrogen sulfide absorption cavity 4. The top of the tower body 1 is provided with a treated gas outlet 5, and the bottom of the tower body 1 is provided with a hydrogen sulfide-rich liquid outlet 6. The hydrogen sulfide absorption cavity 4 is located inside and near the hydrogen sulfide... A gas-liquid separation hydrophilic membrane 7 is installed at the hydrogen-rich liquid outlet 6. This membrane prevents gas from escaping from the hydrogen sulfide-rich liquid outlet 6, allowing the hydrogen sulfide-rich liquid to pass through it and exit smoothly from the outlet 6, thus preventing carbon dioxide from reacting with the liquid due to prolonged contact. A gas-to-be-treated inlet 8 is located on the side wall of the hydrogen sulfide absorption chamber 4, above the gas-liquid separation hydrophilic membrane 7. A plate-type microchannel unit is located inside the hydrogen sulfide absorption chamber 4, above the gas-to-be-treated inlet 8. 9. A hydrogen sulfide absorbent inlet 10 is provided on the side wall of the hydrogen sulfide absorption chamber 4 and above the plate-type microchannel unit 9; a desulfurization gas outlet 11 is provided on the side wall of the hydrogen sulfide absorption chamber 4 near the highest point of the inclined partition plate 2; a carbon dioxide rich liquid outlet 12 is provided on the side wall of the carbon dioxide absorption chamber 4 near the lowest point of the inclined partition plate 2; and a desulfurization gas inlet 13 is provided on the side wall of the carbon dioxide absorption chamber 3 above the carbon dioxide rich liquid outlet 12. The desulfurization gas inlet 13 is connected to the desulfurization gas outlet 11 through the desulfurization gas conduit 14. A baffle-type staggered plate group 15 is provided inside the carbon dioxide absorption chamber 3 and above the desulfurization gas inlet 13. A carbon dioxide absorbent outlet 16 is provided on the side wall of the carbon dioxide absorption chamber 3 and above the baffle-type staggered plate group 15. A gas-liquid separation hydrophobic membrane 17 is provided inside the carbon dioxide absorption chamber 3 and above the carbon dioxide absorbent outlet 16. The gas-liquid separation hydrophobic membrane 17 is located below the treated gas outlet 5.

[0019] The gas-liquid separation hydrophobic membrane 17 and the gas-liquid separation hydrophilic membrane 7 are both pull-out modular designs. The tower body 1 has an upper pull-out port 18 and a lower pull-out port 19 on its side wall. Upper support rails 20 are located inside the tower body 1 on both sides of the upper pull-out port 18, and lower support rails 21 are located inside the tower body 1 on both sides of the lower pull-out port 19. The pull-out modular gas-liquid separation hydrophobic membrane extends from the upper pull-out port 18 and is supported on the upper support rail 20, while the pull-out modular gas-liquid separation hydrophilic membrane extends from the lower pull-out port 19 and is supported on the lower support rail 21. This pull-out modular design facilitates the installation and replacement of the gas-liquid separation hydrophobic membrane 17 and the gas-liquid separation hydrophilic membrane 7, greatly simplifying subsequent maintenance procedures.

[0020] The gas-liquid separation hydrophobic membrane 17 includes a hydrophobic membrane body made of PTFE material, and membrane pores distributed on the surface of the hydrophobic membrane body, with an inner diameter of 0.15-0.35 μm. The gas-liquid separation hydrophilic membrane 7 includes a hydrophilic membrane body made of PVDF material, and membrane pores distributed on the surface of the hydrophilic membrane body, with an inner diameter of 0.55-0.65 μm.

[0021] like Figure 2 As shown, the plate-type microchannel unit 9 adopts a pull-out modular plate-type microchannel. The tower body 1 has a pull-out opening 22 on its side wall. The tower body 1 is provided with a bearing guide rail 23 on both sides of the pull-out opening 22. The pull-out modular plate-type microchannel extends from the pull-out opening 22 and is supported on the bearing guide rail 23.

[0022] Specifically, such as Figure 3 , Figure 4 As shown, the plate-type microchannel unit 9 includes a square frame 24 and multiple corrosion-resistant plates 25. The multiple corrosion-resistant plates 25 are stacked side by side in the square frame 24. A row of vertical microchannels 26 is provided on the surface of each corrosion-resistant plate 25. Protrusions 27 are distributed on the inner wall surface of each vertical microchannel 26. The protrusions 27 are used to disrupt the gas-liquid boundary layer, increase turbulence, and improve the mass transfer coefficient. A pull-out handle 28 is provided on the outer side of the square frame 24, and rollers 29 are provided on the bottom of both sides of the square frame 24. The rollers 29 are supported on the support rail 23 and can roll along the support rail 23. The corrosion-resistant plates 25 are made of silicon carbide ceramic or PTFE material. The diameter of the vertical microchannels is 50-300μm and the length is 4-6cm.

[0023] Working principle: To solve the core problem of low H2S concentration in acid gas caused by CO2 co-absorption in amine desulfurization, breakthroughs are needed in two dimensions: enhancing H2S absorption selectivity and optimizing acid gas separation efficiency.

[0024] The essential difference between amine-based absorption of H2S and CO2 lies in: • H2S: Can react directly with the basic site (-NH) of amines. - / -N - A rapid protonation reaction occurs (without intermediate steps); • CO2: It needs to be hydrated to H2CO3 first. Its reaction with tertiary amines (such as MDEA) requires hydration catalysis. It is characterized by slow rate and low equilibrium constant.

[0025] Therefore, the technical concept of the utility model is as follows: improve the absorption tower and design an acid gas separation absorption tower. Utilize the characteristic that H2S has a weaker binding force with amines to preferentially absorb H2S gas and then absorb CO2 gas, thereby achieving acid gas separation treatment of H2S and CO2 gas in natural gas, and solving the problem of low H2S concentration in acid gas caused by CO2 co-absorption in amine desulfurization.

[0026] This application employs a plate-type microchannel unit within the hydrogen sulfide absorption chamber 4. The vertical microchannels within this unit have a diameter of 50-300 μm and a length of 4-6 cm. This design aims to shorten the contact time between the natural gas (the gas to be treated) and the absorbent. Since H2S reacts quickly while CO2 reacts slowly, the mechanism is that the short diffusion path length of the microchannels is only 4-6 cm, thus controlling the gas-liquid contact time to within 50 ms. Within 50 ms, H2S is completely absorbed by the absorbent, while CO2 requires a reaction time of 100 ms, resulting in insufficient reaction time and CO2 being "retained" in the gas phase. Based on the plate-type microchannel unit, by controlling the gas flow rate of the natural gas, the gas-liquid contact time is further controlled to within 50 ms, preventing CO2 from reacting and being absorbed within the hydrogen sulfide absorption chamber 4. The CO2 in the gas phase is then sent to the carbon dioxide absorption chamber 3 for absorption, thereby achieving the purpose of acid gas classification and treatment.

[0027] Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described herein, as well as the features of those different embodiments or examples, without contradiction. Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. An acid gas separation and absorption tower, characterized in that: The system includes a tower body and an inclined partition plate located within the tower body. The inclined partition plate divides the tower body into upper and lower cavities. The cavity above the inclined partition plate is the carbon dioxide absorption cavity, and the cavity below the inclined partition plate is the hydrogen sulfide absorption cavity. The top of the tower body has a treated gas outlet, and the bottom of the tower body has a hydrogen sulfide-rich liquid outlet. The side wall of the hydrogen sulfide absorption cavity has a gas inlet for untreated gas. A plate-type microchannel unit is located within the hydrogen sulfide absorption cavity and above the gas inlet for untreated gas. A hydrogen sulfide absorbent is located on the side wall of the hydrogen sulfide absorption cavity and above the plate-type microchannel unit. The hydrogen sulfide absorption chamber has a desulfurization gas outlet located on the side wall near the highest point of the inclined partition plate. The carbon dioxide absorption chamber has a carbon dioxide rich liquid outlet located on the side wall near the lowest point of the inclined partition plate. The carbon dioxide absorption chamber has a desulfurization gas inlet located on the side wall above the carbon dioxide rich liquid outlet. The desulfurization gas inlet is connected to the desulfurization gas outlet via a desulfurization gas conduit. The carbon dioxide absorption chamber has a baffle-type staggered plate assembly located inside and above the desulfurization gas inlet. The carbon dioxide absorbent outlet is located on the side wall of the carbon dioxide absorption chamber above the baffle-type staggered plate assembly.

2. The acid gas classification and absorption tower according to claim 1, characterized in that: A gas-liquid separation hydrophilic membrane is provided inside the hydrogen sulfide absorption chamber and near the hydrogen sulfide rich liquid outlet. The gas-liquid separation hydrophilic membrane is used to block gas and allow the hydrogen sulfide rich liquid to pass through the gas-liquid separation hydrophilic membrane.

3. The acid gas classification and absorption tower according to claim 2, characterized in that: A gas-liquid separation hydrophobic membrane is provided inside the carbon dioxide absorption chamber and above the carbon dioxide absorbent, and the gas-liquid separation hydrophobic membrane is located below the treated gas discharge outlet.

4. The acid gas classification and absorption tower according to claim 3, characterized in that: The plate-type microchannel unit adopts a pull-out modular plate-type microchannel. The tower body has a pull-out opening on its side wall. The tower body is equipped with load-bearing guide rails on both sides of the pull-out opening. The pull-out modular plate-type microchannel extends from the pull-out opening and is supported on the load-bearing guide rails.

5. The acid gas classification and absorption tower according to claim 4, characterized in that: The plate-type microchannel unit includes a square frame and multiple corrosion-resistant plates. The multiple corrosion-resistant plates are stacked side by side in the square frame. A row of vertical microchannels is provided on the surface of the corrosion-resistant plates, and protrusions are distributed on the inner wall surface of the vertical microchannels.

6. The acid gas classification and absorption tower according to claim 5, characterized in that: The outer side of the square frame is provided with a pull-out handle, and the bottom of both sides of the square frame is provided with rollers. The rollers are supported on the support rail and can roll along the support rail.

7. The acid gas classification and absorption tower according to claim 6, characterized in that: The corrosion-resistant plate is made of silicon carbide ceramic or PTFE material; the vertical microchannel has a diameter of 50-300μm and a length of 4-6cm.

8. The acid gas classification and absorption tower according to claim 3, characterized in that: The gas-liquid separation hydrophobic membrane is a pull-out modular gas-liquid separation hydrophobic membrane, and the gas-liquid separation hydrophilic membrane is a pull-out modular gas-liquid separation hydrophilic membrane. The tower body has an upper pull-out port and a lower pull-out port on its side wall. The tower body has upper support guide rails on both sides of the upper pull-out port and lower support guide rails on both sides of the lower pull-out port. The pull-out modular gas-liquid separation hydrophobic membrane extends from the upper pull-out port and is supported on the upper support guide rail, and the pull-out modular gas-liquid separation hydrophilic membrane extends from the lower pull-out port and is supported on the lower support guide rail.

9. The acid gas classification and absorption tower according to claim 8, characterized in that: The gas-liquid separation hydrophobic membrane includes a hydrophobic membrane body made of PTFE material, with membrane pores distributed on its surface, the inner diameter of which is 0.15-0.35 μm; the gas-liquid separation hydrophilic membrane includes a hydrophilic membrane body made of PVDF material, with membrane pores distributed on its surface, the inner diameter of which is 0.55-0.65 μm.

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