An integrated process for the treatment of high-hydrocarbon-acid gas

Abstract

The present application relates to the chemical industry field, specifically to an integrated treatment process of high hydrocarbon-containing acid gas, the high hydrocarbon-containing acid gas is sequentially treated by an acid gas pretreatment unit, a sulfur preparation unit and a tail gas incineration unit, wherein the treatment process of the acid gas pretreatment unit is as follows: the high hydrocarbon-containing acid gas from the upstream enters an acid gas liquid separator to remove condensate; the gas after the liquid separation enters an acid gas absorption tower to be in countercurrent contact with the lean liquid from top to bottom to selectively absorb H2S and part of CO2; the rich liquid at the bottom is pressurized by a rich liquid pump and then sent to a matched solvent regeneration unit, the regenerated lean liquid is returned to the absorption tower for recycling, and the high-concentration acid gas desorbed at the top of the regeneration tower is sent to the sulfur preparation unit. The process is efficient and stable, the acid gas pretreatment unit effectively removes hydrocarbons and enriches H2S, thereby providing stable and high-quality feed for the downstream sulfur preparation unit, and fundamentally solving the problem of deactivation of the sulfur preparation furnace and catalyst due to carbon deposition.

Description

Technical Field

[0001] This invention relates to the field of chemical technology, specifically an integrated treatment process for acidic gases with high hydrocarbon content. Background Technology

[0002] Industries such as oil refining, coal chemical industry, and natural gas purification produce large amounts of acidic gases containing hydrogen sulfide. These acidic gases typically contain complex components such as hydrocarbons and carbon dioxide. Direct emission or incineration of these gases would cause serious environmental pollution and waste of sulfur resources.

[0003] In existing technologies, the Claus process is the core technology for treating acidic gases, but it faces challenges when treating acidic gases with high hydrocarbon content, namely, hydrocarbons in the sulfur production furnace can easily lead to carbon buildup, interfere with air distribution control, and reduce sulfur conversion rate.

[0004] While individual amine-based desulfurization, Claus reaction, and tail gas treatment technologies are all mature, how to efficiently and stably integrate them to cope with complex and variable acid gas sources and achieve optimal economic and environmental benefits remains a pressing technical challenge in this field. In particular, a standardized process is needed that can cover the entire process from source purification to end-of-pipe emissions and can be flexibly configured according to the gas source properties and environmental requirements.

[0005] In addition, the existing exhaust gas treatment structure does not completely remove acidic substances, resulting in insufficient recovery of sulfur resources and failing to truly achieve a balance between resource utilization, greening, and economic efficiency in the treatment of acidic gases. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide an integrated treatment process for acidic gases with high hydrocarbon content.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0008] An integrated treatment process for high-hydrocarbon-content acidic gas involves the gas sequentially passing through an acidic gas pretreatment unit, a sulfur production unit, and a tail gas incineration unit. The acidic gas pretreatment unit's process is as follows:

[0009] High-hydrocarbon acidic gas from upstream first enters the acidic gas separator to remove condensate;

[0010] After separation, the gas enters the acid gas absorption tower and comes into countercurrent contact with the lean liquid flowing from top to bottom, selectively absorbing H2S and part of CO2.

[0011] The purified fuel gas exiting from the top of the tower is sent to the fuel gas pipeline network or power station;

[0012] The rich liquid at the bottom of the tower is pressurized by the rich liquid pump and sent to the matching solvent regeneration unit. The regenerated lean liquid is returned to the absorption tower for recycling. The high-concentration acid gas desorbed from the top of the regeneration tower is sent to the sulfur production unit.

[0013] The above process can remove complex components such as light hydrocarbons to obtain clean, high-concentration acidic gas.

[0014] Furthermore, the processing procedure of the sulfur production unit is as follows:

[0015] Clean acidic gas from the acidic gas pretreatment unit, along with air or oxygen supplied by the sulfur-making blower, enters the sulfur-making combustion furnace.

[0016] The high-temperature process gas is cooled and recovered by passing through the steam generator of the sulfur production furnace and the multi-stage condenser in sequence, while liquid sulfur is condensed and separated.

[0017] After each stage of condenser, the process gas is reheated by a steam heater and then enters the corresponding converter for a low-temperature catalytic Claus reaction to further generate elemental sulfur.

[0018] All the liquid sulfur flowing out from the bottom of the condenser is collected in the sulfur sealing tank, and the final product is sulfur.

[0019] Furthermore, the processing procedure of the exhaust gas incineration unit is as follows:

[0020] The exhaust gas enters the exhaust gas incinerator, where the remaining sulfides, H2, and hydrocarbons are completely burned into SO2, H2O, and CO2 at a high temperature of ≥600℃.

[0021] The high-temperature flue gas generated by incineration is cooled to 280℃~300℃ after heat recovery by a waste heat boiler and then sent to subsequent flue gas desulfurization facilities.

[0022] Furthermore, the high-hydrocarbon acidic gas is sequentially processed through an acidic gas pretreatment unit, a sulfur production unit, a tail gas treatment unit, and a tail gas incineration unit. The processing procedure of one of the tail gas treatment units is as follows:

[0023] The sulfur production tail gas is mixed with hydrogen, heated, and then enters the hydrogenation reactor. Under the action of the tail gas hydrogenation catalyst, SO2 and S... X COS is reduced by hydrogenation or hydrolyzed to H2S and S;

[0024] After hydrogenation, the exhaust gas is cooled by a condenser and the steam is recovered. At the same time, liquid sulfur is separated by condensation.

[0025] After cooling, the hydrogenation tail gas is mixed with industrial air, heated, and then enters the oxidation reactor. Under the action of a catalyst, the remaining H2S in the process gas is directly catalytically oxidized into elemental sulfur.

[0026] The exhaust gas after the oxidation reaction is cooled by a condenser and the steam is recovered. At the same time, liquid sulfur is separated by condensation.

[0027] All liquid sulfur flowing from the bottom of the condenser is collected in the sulfur sealing tank, and the final product is sulfur.

[0028] Another type of exhaust gas treatment unit processes the following:

[0029] The sulfur production tail gas is mixed with hydrogen, heated, and then enters the hydrogenation reactor. Under the action of the tail gas hydrogenation catalyst, SO2 and S... X COS is reduced by hydrogenation or hydrolyzed to H2S;

[0030] After hydrogenation, the tail gas is cooled by a steam generator and the heat is recovered to generate steam. After being cooled by the tail gas quench tower, it enters the tail gas absorption tower and comes into countercurrent contact with lean or semi-lean liquid. The H2S in the tail gas is absorbed. The rich liquid that has absorbed H2S is sent to the matching solvent regeneration unit for treatment.

[0031] The purified exhaust gas at the top of the exhaust gas absorption tower is separated into liquids by the liquid separator at the top of the absorption tower before entering the exhaust gas incineration unit.

[0032] Furthermore, the light hydrocarbons flashed out by the acid gas pretreatment unit are sent to a flare or incinerator.

[0033] Furthermore, in the sulfur production unit's sulfur combustion furnace, the air volume is adjusted in real time using an online H2S / SO2 ratio analyzer to precisely control the molar ratio of H2S to SO2 to be 2:1.

[0034] Furthermore, the sulfur production unit is equipped with two- or three-stage converters for low-temperature catalytic Claus reaction.

[0035] The sulfur production unit is equipped with two or three stages of converters for low-temperature catalytic Claus reaction.

[0036] Furthermore, an air inlet pipe is connected to the outside of the tail gas absorption tower, a tail gas pipe is installed at the top of the tail gas absorption tower, a rich amine liquid discharge pipe is installed near the bottom of the outside of the tail gas absorption tower, two sets of main lean amine liquid supply pipes are installed on the outside of the tail gas absorption tower, a baffle plate is installed on the inside of the tail gas absorption tower near the tail gas pipe, two sets of amine storage sleeves are installed inside the tail gas absorption tower, the amine storage sleeves are connected to the main lean amine liquid supply pipes, the two sets of amine storage sleeves are arranged at an interval, a gas washing component is installed on the amine storage sleeves, and a liquid guide plate is installed on the inner bottom wall of the tail gas absorption tower.

[0037] An I-shaped gas guide pipe is installed on the outside of the tail gas absorption tower, near the tail gas pipe. A reflux box is installed at one end of the I-shaped gas guide pipe. Two branches of the I-shaped gas guide pipe are connected to the interior of the tail gas absorption tower and the tail gas pipe, respectively, with a baffle plate as the dividing point. A lean amine solution supply pipe is installed at the top of the reflux box, extending into the interior of the reflux box. Multiple filter plates are evenly spaced inside the reflux box. One end of the lean amine solution supply pipe passes through the multiple filter plates. The inner bottom wall of the reflux box is equipped with… The interceptor plate and the I-shaped air guide pipe are located inside the reflux box. One end of the I-shaped air guide pipe is equipped with a diversion pipe. A valve plate motor is installed between the two branches of the I-shaped air guide pipe. The two branches of the I-shaped air guide pipe are each equipped with a movable circular valve plate. The two output ends of the valve plate motor are fixedly connected to the two circular valve plates respectively. The circular valve plates are arranged in a longitudinal and transverse manner to ensure that one set of I-shaped air guide pipes is in an open and closed state while the other set is in a closed state. The inner bottom wall of the reflux box is divided into two areas by the interceptor plate, one of which is a liquid seal area.

[0038] Furthermore, the gas washing assembly includes a liquid storage chamber, a partition ring, a protective layer, a slow-flow cone, and a spray head. The liquid storage chamber is located in the middle of the amine storage sleeve. The partition ring is located inside the liquid storage chamber and divides the liquid storage chamber into two completely enclosed spaces. The protective layer is located on the top surface of the partition ring. The amine storage sleeve is annular in shape, with the slow-flow cone located on the inner ring surface of the amine storage sleeve. The spray head is located on the inner ring surface of the amine storage sleeve and is connected to the liquid storage chamber through it.

[0039] The beneficial effects achieved by this invention are:

[0040] 1. The process of this invention is highly efficient and stable. The acid gas pretreatment unit effectively removes hydrocarbons and enriches H2S, providing a stable and high-quality feed for the downstream sulfur production unit, fundamentally solving the problem of deactivation of the sulfur production furnace and catalyst due to carbon buildup.

[0041] 2. This invention adopts a fully integrated and optimized approach, seamlessly connecting the four units of pretreatment, sulfur production, tail gas treatment, and incineration, forming a highly efficient and synergistic standardized integrated process, which is particularly suitable for treating complex high-hydrocarbon acidic gases from industries such as oil refining and coal chemical engineering.

[0042] 3. This invention features flexibility and high recovery rate. The sulfur production unit can adopt two-stage or three-stage catalytic reaction, and the tail gas treatment unit can flexibly select process technology according to environmental protection requirements. It can meet different emission standards and achieve a total sulfur recovery rate of up to 99.9%.

[0043] 4. The process of this invention can achieve energy integration, fully recover the heat of reaction and condensation at each stage within the system, and generate high, medium and low pressure steam for heating the device, solvent regeneration and external output, which significantly reduces the energy consumption of the device operation.

[0044] 5. This invention has a wide range of applications. The high-hydrocarbon acidic gas can be generated from coal gasification units (coal to natural gas, low-temperature coal pyrolysis, etc.), coal syngas purification units (low-temperature methanol washing, etc.), shift conversion units, and ammonia synthesis and hydrogen production units in the coal chemical industry, etc.; it can also be generated from gases and sulfur-containing wastewater generated from various hydrogenation units, atmospheric and vacuum distillation units, catalytic cracking units, and coking units in the oil refining industry, respectively, after being treated by amine desulfurization units and acidic water stripping units, to generate acidic gas rich in H2S; it can also be generated from acidic gases generated in other chemical industries such as natural gas purification units and carbon disulfide units; it can be one of the above-mentioned acidic gases, or a mixture of several acidic gases.

[0045] 6. The exhaust gas absorption tower structure of the present invention is optimized, adopting a multi-stage structure to thoroughly absorb acidic substances. Attached Figure Description

[0046] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0047] Figure 1 This is a process flow diagram of the acid gas pretreatment unit of the present invention;

[0048] Figure 2 This is a process flow diagram of the sulfur production unit in Embodiment 1 of the present invention;

[0049] Figure 3 This is a process flow diagram of the sulfur production unit in Embodiments 2 and 3 of the present invention;

[0050] Figure 4 This is a process flow diagram of the exhaust gas treatment unit in Embodiment 2 of the present invention;

[0051] Figure 5 This is a process flow diagram of the exhaust gas treatment unit in Embodiment 3 of the present invention;

[0052] Figure 6 This is a process flow diagram of the exhaust gas incineration unit of the present invention;

[0053] Figure 7 This is a schematic diagram of the tail gas absorption tower structure in this invention;

[0054] Figure 8 This is a schematic diagram of the internal structure of the exhaust gas absorption tower in this invention. Figure 1 ;

[0055] Figure 9 This is the present invention. Figure 8 Enlarged schematic diagram of section A in the middle;

[0056] Figure 10 This is a schematic diagram of the internal structure of the exhaust gas absorption tower in this invention. Figure 2 ;

[0057] Figure 11 This is a schematic diagram of the internal structure of the exhaust gas absorption tower in this invention. Figure 3 ;

[0058] Figure 12 This is a schematic diagram of the internal structure of the exhaust gas absorption tower in this invention. Figure 4 ;

[0059] Figure 13 This is a schematic diagram of the reflux box structure in this invention. Figure 1 ;

[0060] Figure 14 This is a schematic diagram of the reflux box structure in this invention. Figure 2 ;

[0061] Figure 15 This is a schematic diagram of the reflux box structure in this invention. Figure 3 .

[0062] In the diagram: 1. Acid gas separator; 2. Acid gas absorption tower; 3. Sulfur combustion furnace; 4. First-stage condenser; 5. First-stage heater; 6. First-stage converter; 7. Second-stage condenser; 8. Second-stage heater; 9. Second-stage converter; 10. Third-stage condenser; 11. Third-stage heater; 12. Third-stage converter; 13. Fourth-stage condenser; 14. Sulfur sealer; 15. Hydrogenation reactor; 16. Hydrogenation reaction condenser; 17. Hydrogenation tail gas heater; 18. Oxidation reactor; 19. Oxidation reaction condenser; 20. Steam generator; 21. Tail gas quenching. 22. Tail gas absorption tower; 23. Tail gas incinerator; 24. Main lean amine liquid supply pipe; 25. Inlet pipe; 26. Rich amine liquid discharge pipe; 27. Tail gas pipe; 28. Liquid guide plate; 29. ​​Amine storage sleeve; 30. Flow guide groove; 31. Liquid storage chamber; 32. Separating ring; 33. Protective layer; 34. Slow flow cone; 35. Liquid spray head; 36. Cut-off plate; 37. Return box; 38. I-shaped gas guide pipe; 39. Secondary lean amine liquid supply pipe; 40. Valve plate motor; 41. Interceptor plate; 42. Diversion pipe; 43. Liquid seal zone; 44. Circular valve plate; 45. Multi-stage filter plate; 46. Vertical filter plate. Detailed Implementation

[0063] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0064] Example 1:

[0065] like Figure 1 , Figure 2 , Figure 6As shown, taking the treatment of acidic gas produced by a coal chemical plant's coal-to-natural gas conversion unit as an example, the acidic gas is sequentially processed through an acidic gas pretreatment unit, a sulfur production unit, and a tail gas incineration unit. Specifically:

[0066] like Figure 1 As shown, the treatment process of the acid gas pretreatment unit is as follows: acid gas (H2S ~30%, hydrocarbons ~5%) is separated into liquids by acid gas separator 1 and then enters acid gas absorption tower 2, where it comes into countercurrent contact with 45wt% MDEA lean solution; the rich solution enters the solvent regeneration tower after heat exchange, and the bottom of the tower is heated and regenerated by 0.35MPaG steam; the regenerated lean solution is returned to acid gas absorption tower 2 for recycling, and the H2S concentration of the regenerated acid gas is increased to ~55% before being sent to the sulfur production unit.

[0067] like Figure 2 As shown, the sulfur production unit's processing procedure is as follows: A high-temperature Claus reaction combined with a three-stage low-temperature catalytic Claus reaction is employed in the sulfur production combustion furnace 3. Regenerated acidic gas and air are burned in the sulfur production furnace (>1050℃). After heat recovery in the waste heat boiler, the process gas is condensed in a primary condenser 4 to recover heat. It then sequentially passes through a primary heater 5, a primary converter 6, a secondary condenser 7, a secondary heater 8, a secondary converter 9, a tertiary condenser 10, a tertiary heater 11, a tertiary converter 12, and a quaternary condenser 13 to achieve a low-temperature catalytic Claus reaction. All liquid sulfur flowing from the bottom of the condensers is collected in a sulfur sealing tank 14, ultimately producing sulfur. The sulfur production tail gas is sent to the tail gas incineration unit for further treatment.

[0068] The entire process utilizes an online H2S / SO2 analyzer for precise air distribution.

[0069] like Figure 6 As shown, the treatment process of the tail gas incineration unit is as follows: the sulfur production tail gas is incinerated in the tail gas incinerator 23 (800℃), and the temperature of the high-temperature flue gas is reduced to below 300℃ after waste heat recovery, and then sent to the subsequent flue gas desulfurization facility. The SO2 emission concentration meets the special emission limit requirements.

[0070] The aforementioned integrated system operates continuously and stably, with a sulfur recovery rate of approximately 96.5%, effectively solving the problem of treating acidic gases with high hydrocarbon content.

[0071] Example 2:

[0072] like Figure 1 , Figure 3 , Figure 4 , Figure 6 As shown, taking the treatment of acidic gas generated by a coal pyrolysis unit in a coal chemical industry as an example, the acidic gas is sequentially processed through an acidic gas pretreatment unit, a sulfur production unit, a tail gas treatment unit, and a tail gas incineration unit. Specifically:

[0073] like Figure 1 As shown, the treatment process of the acid gas pretreatment unit is as follows: Acid gas (H2S ~25%, hydrocarbons ~19%) is separated by acid gas separator 1 and then enters acid gas absorption tower 2, where it comes into countercurrent contact with 40wt% MDEA lean solution. The rich solution, after heat exchange, enters the solvent regeneration tower, where the bottom is heated and regenerated using 0.35MPaG steam. The regenerated lean solution is returned to acid gas absorption tower 2 for recycling. The H2S concentration of the regenerated acid gas is increased to ~65% before being sent to the sulfur production unit.

[0074] like Figure 3 As shown, the sulfur production unit employs a high-temperature Claus reaction process in a sulfur furnace followed by a two-stage low-temperature catalytic Claus reaction. The regenerated acidic gas is burned with air in the sulfur furnace (>1050℃). After heat recovery in a waste heat boiler, the process gas is condensed in a primary condenser 4 to recover heat, and then sequentially passes through a primary heater 5, a primary converter 6, a secondary condenser 7, a secondary heater 8, a secondary converter 9, and a tertiary condenser 10 to achieve a low-temperature catalytic Claus reaction. All liquid sulfur flowing from the bottom of the condensers is collected in a sulfur sealing tank 14, ultimately producing sulfur. The sulfur production tail gas is sent to a tail gas treatment unit for further processing.

[0075] The entire process utilizes an online H2S / SO2 analyzer for precise air distribution.

[0076] like Figure 4 As shown, the tail gas treatment unit employs a selective oxidation process. The tail gas, after three stages of condensation, enters the hydrogenation reactor 15, where all sulfides are converted to H2S and S under the action of a hydrogenation catalyst. After the liquid sulfur is condensed and its heat recovered by the hydrogenation reaction condenser 16, it is reheated by the hydrogenation tail gas heater 17 and enters the oxidation reactor 18. Under the action of a selective oxidation catalyst, all H2S is directly oxidized to S. The liquid sulfur is then condensed and its heat recovered by the oxidation reaction condenser 19. The purified tail gas is then sent to the tail gas incineration unit.

[0077] like Figure 6 As shown, the treatment process of the exhaust gas incineration unit is as follows: the purified exhaust gas is incinerated in the exhaust gas incinerator 23 (900℃), and the temperature of the high-temperature flue gas is reduced to below 300℃ after waste heat recovery, and then sent to the subsequent flue gas desulfurization facility. The SO2 emission concentration meets the special emission limit requirements.

[0078] The integrated system described above operates continuously and stably, with a sulfur recovery rate of approximately 99.0%, effectively solving the problem of treating acidic gases with high hydrocarbon content.

[0079] Example 3:

[0080] like Figure 1 , Figure 3 , Figure 5 , Figure 6 As shown, taking the treatment of acidic gas from a chemical plant as an example, the acidic gas sequentially passes through an acidic gas pretreatment unit, a sulfur production unit, a tail gas treatment unit, and a tail gas incineration unit. Specifically:

[0081] like Figure 1 As shown, the treatment process of the acid gas pretreatment unit is as follows: Acid gas (H2S ~35%, hydrocarbons ~10%) is separated by acid gas separator 1 and then enters acid gas absorption tower 2, where it comes into countercurrent contact with 40wt% MDEA lean solution. The rich solution, after heat exchange, enters the solvent regeneration tower, where the bottom is heated and regenerated using 0.35MPaG steam. The regenerated lean solution is returned to acid gas absorption tower 2 for recycling. The H2S concentration of the regenerated acid gas is increased to ~70% before being sent to the sulfur production unit.

[0082] like Figure 3 As shown, the sulfur production unit employs a high-temperature Claus reaction process in a sulfur furnace followed by a two-stage low-temperature catalytic Claus reaction. The regenerated acidic gas is burned with air in the sulfur furnace (>1150℃). After heat recovery in a waste heat boiler, the process gas is condensed in a primary condenser 4 to recover heat, and then sequentially passes through a primary heater 5, a primary converter 6, a secondary condenser 7, a secondary heater 8, a secondary converter 9, and a tertiary condenser 10 to achieve a low-temperature catalytic Claus reaction. All liquid sulfur flowing from the bottom of the condensers is collected in a sulfur sealing tank 14, ultimately producing sulfur. The sulfur production tail gas is sent to a tail gas treatment unit for further processing.

[0083] The entire process utilizes an online H2S / SO2 analyzer for precise air distribution.

[0084] like Figure 5 As shown, the tail gas treatment unit employs a hydrogenation reduction absorption process. After three-stage condensation, the tail gas in the hydrogenation reactor 15 converts all sulfides into H2S and S under the action of a hydrogenation catalyst. After heat recovery in the steam generator 20, steam is generated, which is then rapidly cooled in the tail gas quench tower 21 before entering the tail gas absorption tower 22 where it comes into countercurrent contact with the lean amine solution, absorbing the H2S in the tail gas. The MDEA-rich solution, now rich in H2S, is sent to the matching solvent regeneration unit for further treatment.

[0085] like Figures 7-15As shown, an inlet pipe 25 is connected to the outside of the tail gas absorption tower 22, a tail gas pipe 27 is installed at the top of the tail gas absorption tower 22, a rich amine liquid discharge pipe 26 is installed near the bottom of the outside of the tail gas absorption tower 22, two sets of main lean amine liquid supply pipes 24 are installed on the outside of the tail gas absorption tower 22, a baffle plate 36 is installed inside the tail gas absorption tower 22 near the tail gas pipe 27, two sets of amine storage sleeves 29 are installed inside the tail gas absorption tower 22, the amine storage sleeves 29 are connected to the main lean amine liquid supply pipes 24, the two sets of amine storage sleeves 29 are arranged vertically and alternately, a gas washing component is installed on the amine storage sleeves 29, and a liquid guide plate 28 is installed on the inner bottom wall of the tail gas absorption tower 22 near the bottom.

[0086] An I-shaped gas guide pipe 38 is installed on the outer side of the tail gas absorption tower 22, near the tail gas pipe 27. The I-shaped gas guide pipe 38 includes two branch pipes, which are not connected. A valve plate motor 40 is installed between the two branch pipes. A reflux box 37 is installed at one end of the I-shaped gas guide pipe 38. The two branch pipes of the I-shaped gas guide pipe 38 are connected to the interior of the tail gas absorption tower 22 and the tail gas pipe 27 respectively, with the cut-off plate 36 as the dividing point. A lean amine liquid supply pipe 39 is installed at the top of the reflux box 37, extending into the interior of the reflux box 37. Multiple filter plates 45 are evenly spaced inside the reflux box 37. Figure 15 As shown, the multi-stage filter plate 45 is a half-section filter plate. The multi-stage filter plate 45 can be made of fluoropolymer (FMS / glass fiber composite filter media), with one half being solid and the other half being a perforated plate. This design ensures that the treated gas-liquid mixture can only enter a region separated by the interceptor plate 41 on the inner bottom wall of the return box 37 through the perforated plate, preventing liquid from entering the liquid seal zone 43. One end of the lean amine liquid supply pipe 39 passes through the multi-stage filter plate 45. The inner bottom wall of the return box 37 is equipped with the interceptor plate 41. The I-shaped gas guide pipe 38, located inside the return box 37, has a modified... A valve plate motor 40 is installed between the two branches of the flow pipe 42 and the I-shaped air guide pipe 38. A circular valve plate 44 is movably installed inside the I-shaped air guide pipe 38. The two output ends of the valve plate motor 40 are fixedly connected to the two circular valve plates 44 respectively. The internal circular valve plates 44 are arranged in a longitudinal and transverse manner to ensure that one set of I-shaped air guide pipes 38 is in an open and closed state while the other set is in a closed state. The inner bottom wall of the return box 37 is divided into two areas by the interceptor plate 41. One of them is the liquid seal area 43. The liquid seal area 43 is equipped with liquid inlet and liquid outlet for periodically replacing the washing water (lean amine liquid or water).

[0087] In this embodiment, the gas washed by the gas scrubbing assembly is intercepted by the baffle plate 36. It can only enter the diversion pipe 42 through the branch pipe at the lower part of the I-shaped gas guide pipe 38 below the baffle plate 36. The circular valve plate 44 of the lower branch pipe of the I-shaped gas guide pipe 38 is in the open state. The gas enters through the inlet end of the diversion pipe 42 and exits through the other end of the diversion pipe 42. The exhaust end of the diversion pipe 42 is located in the liquid seal area 43 formed by the baffle plate 41 and the inner bottom wall of the return box 37. By filling the closed area with gas scrubbing water (lean amine liquid or water), the gas discharged through the diversion pipe 42 will first pass through the gas scrubbing water and then exit from the liquid surface of the gas scrubbing water. Since the gas cannot pass through the liquid in reverse to enter the exhaust end of the diversion pipe 42, it is ensured that the gas passing through the gas scrubbing water will not have a backflow phenomenon.

[0088] The gas, after passing through the scrubbing water, gathers in the drying area on the other side of the scrubbing water and interceptor plate 41. The gas is dispersed into several groups of flue gas columns through the perforations of the multi-stage filter plate 45 and gradually discharged upwards. Lean amine solution is supplied through the lean amine solution supply pipe 39, which has several micropores on its outer side. Under hydraulic pressure, the supplied lean amine solution is atomized and sprayed out from the micropores to desulfurize the gas entering above the multi-stage filter plate 45. The treated gas is discharged through the vertical filter plate 46 from the upper branch of the I-shaped gas guide pipe 38 and then through the tail gas pipe 27. The vertical filter plate 46 can be made of fluoropolymer (FMS / glass fiber composite filter media). The liquid sprayed from the supply pipe 39 reacts with the gas, and the resulting liquid passes through the multi-stage filter plate 45 and falls into the inner bottom wall of the return box 37, and is discharged through the discharge port. The discharge port can be connected to an external conduit to discharge and collect the liquid after reacting with the gas. It should be noted that the valve plate motor 40 drives the circular valve plates 44 inside the two I-shaped air guide pipes 38 to rotate, thereby realizing air intake and sealing. One of the circular valve plates 44 inside the I-shaped air guide pipe 38 is set horizontally and the other is set vertically. The valve plate motor 40 drives the air intake end and the exhaust end of the I-shaped air guide pipe 38 to always be in a closed state and an open state, thereby realizing the intermittent centralized processing of the gas inside the return box 37. The internal gas reaction is controlled by controlling the running time of the valve plate motor 40. The valve plate motor 40 can be connected to an external delay module to control the deflection time of the valve plate motor 40. The above is the existing technology that can achieve the function required by this device without disclosing its specific structure. Among them, the valve plate motor 40 selected as the option in this solution is a dual output shaft motor.

[0089] Furthermore, the gas washing assembly includes a liquid storage chamber 31, a partition ring 32, a protective layer 33, a slow-flow cone 34, and a spray head 35. The liquid storage chamber 31 is located in the middle of the amine storage sleeve 29. The partition ring 32 is located inside the liquid storage chamber 31 and divides the liquid storage chamber 31 into two completely enclosed spaces. The protective layer 33 is located on the top surface of the partition ring 32. The amine storage sleeve 29 is annular. The slow-flow cone 34 is located on the inner ring surface of the amine storage sleeve 29. The spray head 35 is located on the inner ring surface of the amine storage sleeve 29 and penetrates through the liquid storage chamber 31. The two are connected.

[0090] In this embodiment, the exhaust gas enters the exhaust gas absorption tower 22 through the inlet pipe 25 (accessed at the lower part of the tower body), flows vertically upward along the tower body, and passes through the upper and lower sets of gas washing components in sequence, coming into countercurrent contact with the lean amine liquid to complete the H2S absorption. The purified exhaust gas enters the diversion pipe 42 through the inlet end of the I-shaped gas guide pipe 38 below the baffle plate 36 and enters the return box 37 for the final desulfurization treatment of the exhaust gas. The treated exhaust gas is discharged from the exhaust pipe 27. The rich amine liquid that has absorbed H2S is collected through the liquid guide plate 28 and then transported to the solvent regeneration unit from the rich amine liquid discharge pipe 26.

[0091] Two sets of main lean amine supply pipes 24 are connected to two sets of upper and lower annular amine storage sleeves 29. Lean amine is independently supplied into the storage chamber 31 of each set of storage sleeves 29 through the supply pipes. The partition ring 32 in the storage chamber 31 divides it into two spaces, which can prevent turbulence and flow deviation when the lean amine flows in the annular sleeve. The bottom of the storage chamber 31 is provided with an annular guide groove 30 to further reduce the impact generated by the flow and ensure that the hydraulic pressure in each area of ​​the storage chamber 31 is uniform. The protective layer 33 on the top of the partition ring 32 (made of corrosion-resistant materials such as polytetrafluoroethylene) can resist the corrosion of MDEA amine and extend the service life of the partition ring 32. The two sets of main lean amine supply pipes 24 are connected to lean amine with a certain hydraulic pressure, so that the atomized spray of the spray head 35 (uniformly distributed in an annular shape) can have a certain impact force to impact the exhaust gas and make it flow, so as to better contact and react with the lean amine in the countercurrent.

[0092] The lean amine liquid in the storage chamber 31 is atomized and sprayed through the spray head 35; at the same time, the slow-flow cone 34 of the inner ring of the amine storage sleeve 29 guides the upward-flowing exhaust gas to disperse, avoiding the airflow from directly impacting the spray area and causing droplet splashing, and also allowing the exhaust gas to evenly cover the spray range, which can greatly increase the contact area between the exhaust gas and the lean amine liquid.

[0093] Because the two sets of amine storage sleeves 29 are arranged at intervals, the exhaust gas will pass through the "lower gas washing component for preliminary absorption and then through the upper gas washing component for secondary in-depth absorption", which further improves the H2S removal efficiency.

[0094] The baffle plate 36 is located inside the exhaust pipe 27.

[0095] The liquid guide plate 28 adopts a conical plate structure with a "low middle and high edge" to concentrate and guide the rich amine liquid dripping from the upper and lower gas washing components to the bottom of the tower, while ensuring the discharge efficiency of the rich amine liquid from the rich amine liquid discharge pipe 26.

[0096] The purified tail gas from the top of the tail gas absorption tower 22 is separated into liquids by the liquid separator at the top of the absorption tower and then enters the tail gas incineration unit.

[0097] like Figure 6 As shown, the treatment process of the exhaust gas incineration unit is as follows: the purified exhaust gas is incinerated in the exhaust gas incinerator 23 (600℃), and the temperature of the high-temperature flue gas is reduced to below 300℃ after waste heat recovery, and then sent to the subsequent flue gas desulfurization facility. The SO2 emission concentration meets the special emission limit requirements.

[0098] The integrated system described above operates continuously and stably, with a sulfur recovery rate of approximately 99.9%, effectively solving the problem of treating acidic gases with high hydrocarbon content.

Claims

1. An integrated treatment process for high-hydrocarbon-content acidic gases, characterized in that, The high-hydrocarbon acidic gas is sequentially processed through an acidic gas pretreatment unit, a sulfur production unit, a tail gas treatment unit, and a tail gas incineration unit. The process of the acidic gas pretreatment unit is as follows: The high-hydrocarbon acidic gas from upstream first enters the acidic gas separator (1) to remove condensate; After separation, the gas enters the acid gas absorption tower (2) and comes into countercurrent contact with the lean liquid flowing from top to bottom, selectively absorbing H2S and part of CO2; The purified fuel gas exiting from the top of the tower is sent to the fuel gas pipeline network or power station; The rich liquid at the bottom of the tower is pressurized by the rich liquid pump and sent to the matching solvent regeneration unit. The regenerated lean liquid is returned to the absorption tower for recycling. The high-concentration acid gas desorbed from the top of the regeneration tower is sent to the sulfur production unit. The exhaust gas treatment unit's processing procedure is as follows: The sulfur production tail gas is mixed with hydrogen, heated, and then enters the hydrogenation reactor (15). Under the action of the tail gas hydrogenation catalyst, SO2 and S X COS is reduced by hydrogenation or hydrolyzed to H2S; After hydrogenation, the tail gas is cooled by a steam generator (20) and heat is recovered to generate steam. After being cooled by a tail gas quench tower (21), it enters a tail gas absorption tower (22) and comes into countercurrent contact with lean or semi-lean liquid. H2S in the tail gas is absorbed. The rich liquid that has absorbed H2S is sent to the matching solvent regeneration unit for treatment. The purified tail gas at the top of the tail gas absorption tower (22) is separated into liquids by the liquid separator at the top of the absorption tower and then enters the tail gas incineration unit. An inlet pipe (25) is connected to the outside of the tail gas absorption tower (22). A tail gas pipe (27) is provided at the top of the tail gas absorption tower (22). A rich amine liquid discharge pipe (26) is provided near the bottom of the outside of the tail gas absorption tower (22). Two sets of main lean amine liquid supply pipes (24) are provided on the outside of the tail gas absorption tower (22). A baffle plate (36) is provided on the inside of the tail gas absorption tower (22) and near the tail gas pipe (27). Two sets of amine storage sleeves (29) are provided inside the tail gas absorption tower (22). The amine storage sleeves (29) are connected to the main lean amine liquid supply pipes (24). The two sets of amine storage sleeves (29) are arranged at an interval between the top and bottom. A gas washing component is provided on the amine storage sleeves (29). A liquid guide plate (28) is provided on the inner bottom wall of the tail gas absorption tower (22). An I-shaped gas guide pipe (38) is installed on the outside of the tail gas absorption tower (22) and near the tail gas pipe (27). A reflux box (37) is installed at one end of the I-shaped gas guide pipe (38). The two branches of the I-shaped gas guide pipe (38) are connected to the interior of the tail gas absorption tower (22) and the tail gas pipe (27) respectively, with the cut-off plate (36) as the dividing point. A lean amine liquid supply pipe (39) is installed at the top of the reflux box (37). The lean amine liquid supply pipe (39) extends into the interior of the reflux box (37). Multi-stage filter plates (45) are equidistantly arranged inside the reflux box (37). One end of the lean amine liquid supply pipe (39) passes through the multi-stage filter plates (45). The inner bottom wall of the reflux box (37) is provided with An interceptor plate (41) is provided. An I-shaped air guide pipe (38) is located inside the return box (37) and a diversion pipe (42) is provided at one end. A valve plate motor (40) is provided between the two branches of the I-shaped air guide pipe (38). A circular valve plate (44) is movably provided inside the two branches of the I-shaped air guide pipe (38). The two output ends of the valve plate motor (40) are fixedly connected to the two circular valve plates (44). The circular valve plates (44) are arranged in a longitudinal and transverse manner to ensure that one branch of the I-shaped air guide pipe (38) is in the open state and the other branch is in the closed state. The inner bottom wall of the return box (37) is divided into two groups of areas by the interceptor plate (41), one of which is the liquid seal area (43).

2. The integrated treatment process for high-hydrocarbon-content acidic gas according to claim 1, characterized in that, The processing procedure of the sulfur production unit is as follows: Clean acidic gas from the pretreatment unit, together with air or oxygen supplied by the sulfur-making blower, enters the sulfur-making combustion furnace (3). The high-temperature process gas is cooled and recovered by passing through the steam generator of the sulfur production furnace and the multi-stage condenser in sequence, while liquid sulfur is condensed and separated. After each stage of condenser, the process gas is reheated by a steam heater and then enters the corresponding converter for a low-temperature catalytic Claus reaction to further generate elemental sulfur. All the liquid sulfur flowing out from the bottom of the condenser is collected in the sulfur sealing tank (14), and the final product is sulfur.

3. The integrated treatment process for high-hydrocarbon-content acidic gas according to claim 1, characterized in that, The processing procedure of the exhaust gas incineration unit is as follows: The exhaust gas enters the exhaust gas incinerator (23), where the remaining sulfides, H2, and hydrocarbons are completely burned into SO2, H2O, and CO2 at a high temperature of ≥600℃. The high-temperature flue gas generated by incineration is cooled to 280℃~300℃ after heat recovery by a waste heat boiler and then sent to subsequent flue gas desulfurization facilities.

4. The integrated treatment process for high-hydrocarbon-content acidic gas according to claim 2, characterized in that, In the sulfur production unit's sulfur combustion furnace (3), the air volume is adjusted in real time by an online H2S / SO2 ratio analyzer to precisely control the molar ratio of H2S to SO2 to be 2:

1.

5. The integrated treatment process for high-hydrocarbon-content acidic gas according to claim 2, characterized in that, The sulfur production unit is equipped with two- or three-stage converters for low-temperature catalytic Claus reaction.

6. The integrated treatment process for high-hydrocarbon-content acidic gas according to claim 1, characterized in that, The gas washing assembly includes a liquid storage chamber (31), a partition ring (32), a protective layer (33), a slow-flow cone (34), and a spray head (35). The liquid storage chamber (31) is located in the middle of the amine storage sleeve (29). The partition ring (32) is located inside the liquid storage chamber (31) and divides the liquid storage chamber (31) into two completely enclosed spaces. The protective layer (33) is located on the top surface of the partition ring (32). The amine storage sleeve (29) is annular. The slow-flow cone (34) is located on the inner ring surface of the amine storage sleeve (29). The spray head (35) is located on the inner ring surface of the amine storage sleeve (29) and penetrates through the liquid storage chamber (31).

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