A purification device for coke oven gas
The methanol absorption purification device solves the problem of impurity treatment in coke oven gas, achieving efficient and low-cost purification, reducing equipment investment and energy consumption, and improving product value and production stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 天津德瑞化工技术有限公司
- Filing Date
- 2025-07-01
- Publication Date
- 2026-07-14
AI Technical Summary
The composition of impurities in coke oven gas is complex. Existing desulfurization methods involve high investment, high cost, and insufficient desulfurization depth, leading to increased purification costs, affecting production stability and wasting resources. Furthermore, compressors are prone to clogging.
The methanol absorption method is adopted, which uses a purification device consisting of a water washing ammonia tower, an ammonia stripping tower, an ammonia water refining tower, an ambient temperature methanol washing tower, a low temperature methanol washing tower and a flash evaporation tower. Combined with the multi-stage absorption and separation of methanol and water, the coke oven gas is purified efficiently.
It achieves efficient purification of coke oven gas, reduces equipment investment and energy consumption, reduces waste liquid and slag, increases product value, and achieves a near 100% benzene recovery rate, ensuring production stability and environmental protection.
Smart Images
Figure CN224494102U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of chemical equipment technology, specifically to a purification device for coke oven gas. Background Technology
[0002] Coke oven gas is an important byproduct of the coking process. One ton of coke produces 430-450 cubic meters of coke oven gas, which has significant utilization value. Its main components include H2, CH4, CO, CO2, N4, and C. n H m While coke oven gas contains O2, it also contains many complex impurities that affect its utilization. The main impurities are shown in the table below:
[0003]
[0004] The ammonia and benzene compounds in the above-mentioned impurities can be recovered and reused as useful components. Traditional ammonia recovery methods use sulfuric acid and ammonia to generate sulfuric ammonia. A small part of the deammoniation process uses phosphoric acid to absorb ammonia, and then distills it to generate liquid ammonia or ammonia water. Both of these processes have large investment and high production costs, and the deammoniation accuracy is not high. After deammoniation, the raw coal gas still contains 50 mg / m³ of ammonia, which leads to low product value. The traditional benzene washing process uses oil washing to remove benzene, which has large investment and high energy consumption, and the benzene removal accuracy is not high. After benzene removal, the raw coal gas still contains 2-5 g / m³ of benzene, which not only requires subsequent deep purification, but also wastes benzene resources.
[0005] The core issue in recovering and utilizing the aforementioned useful components lies in desulfurization. Currently, the commonly used desulfurization methods for coke oven gas are dry desulfurization and wet desulfurization. Dry desulfurization mainly utilizes a desulfurization catalyst synthesized from ferric hydroxide and other agents to remove H2S from the gas. The regenerated desulfurizing agent can be reused. Dry desulfurization is mainly applied to desulfurization of coke oven gas with small volumes or secondary desulfurization with high desulfurization precision. Wet desulfurization processes utilize liquid desulfurizing agents to remove H2S and HCN from coke oven gas. Currently, commonly used wet desulfurization methods include the modified ADA method, naphthoquinone method, gel method, FRC method, TH method, HPF method, PDS method, OPT method, complexed iron method, and ammonia catalytic method. Larger-scale coking enterprises typically use wet desulfurization. However, wet desulfurization cannot remove organic sulfur, and inorganic sulfur can only be removed down to 20 mg / m³. The sulfur byproduct of wet desulfurization is of poor quality and low value, and wet desulfurization inevitably produces byproduct salts. To avoid the accumulation of byproduct salts in the desulfurization wastewater... A small amount of waste liquid will be discharged. In the past, the measures taken were to send the discharged desulfurization waste liquid into the coal blending system, but this method would cause environmental problems and pollute the environment. At present, the investment in the treatment of desulfurization waste liquid is large, and although the treatment process seems to be recycled, it also has many shortcomings.
[0006] In summary, desulfurization of coke oven gas faces several challenges. Dry desulfurization involves high investment and costs, making it unsuitable for large-scale coke oven gas production. Traditional wet desulfurization suffers from insufficient desulfurization depth, requiring further deep treatment before utilization, and difficulties in waste liquid treatment, which cannot guarantee the safe, stable, normal, and full-scale operation of subsequent units. If the desulfurized gas is used for other purposes, organic sulfur needs to be converted into inorganic sulfur for removal, resulting in large investments and high costs.
[0007] With the expansion of coking scale and industrial agglomeration, coke oven gas has become an important chemical feedstock. This change in the use of coke oven gas has resulted in the original design specifications for chemical purification being far from meeting current requirements. Abnormal desulfurization in chemical production causes premature failure of the desulfurizing agent in fine desulfurization, affecting production operations, mainly due to sulfur penetration. This necessitates premature replacement of the desulfurizing agent, leading to frequent replacements and increased costs for coke oven gas purification. Furthermore, the high tar and naphthalene content in the purified coke oven gas severely affects the normal operation of compressors. This is mainly because the high tar and naphthalene content in the coke oven gas causes tar gasification and coking during compression, as well as naphthalene condensation and crystallization, resulting in naphthalene blockage in the compressor and preventing normal operation, forcing shutdowns for repairs. Sometimes, the compressor can only operate for 1-2 days before needing to be shut down for emergency repairs, putting production in a very passive position, often resulting in a situation of 1 operating with 2 or 3 on standby.
[0008] The applicant intends to solve the above-mentioned technical problems by methanol absorption, but after a detailed search, no relevant technical solutions were found.
[0009] Therefore, a new technical solution is needed to solve the above-mentioned technical problems. Utility Model Content
[0010] This application provides a purification device for coke oven gas, including a water-washing ammonia tower, a feed pipeline is provided on one side of the water-washing ammonia tower, and the bottom of the water-washing ammonia tower is connected to an ammonia stripping tower.
[0011] The bottom of the ammonia stripping tower is equipped with a wastewater outlet pipeline for the ammonia stripping tower. The top of the ammonia stripping tower is connected to the ammonia refining tower. A pipeline for ammonia-containing materials is installed on one side of the ammonia refining tower. A wastewater outlet pipeline for the ammonia refining tower is installed at the bottom of the ammonia refining tower.
[0012] The top of the ammonia washing tower is connected to the ambient temperature methanol washing tower, and the bottom of the ambient temperature methanol washing tower is connected to the extraction tower. An oil collection pipeline is installed at the top of the extraction tower, and the bottom of the extraction tower is connected to the methanol water separator. The bottom of the methanol water separator is connected to the methanol water separator wastewater collection pipeline. The top of the methanol water separator is connected to the upper middle part of the methanol water separator through the methanol water separator tower top circulation pipeline. One end of the circulation pipeline is connected to the methanol water separator tower top circulation pipeline, and the other end of the circulation pipeline is connected to the ambient temperature methanol washing tower.
[0013] The top of the ambient temperature methanol washing tower is connected to the low temperature methanol washing tower via the top outlet pipeline of the ambient temperature methanol washing tower. The top of the low temperature methanol washing tower is equipped with a clean coal gas outlet pipeline. The bottom of the low temperature methanol washing tower is connected to the flash evaporator. The top of the flash evaporator is connected to the top outlet pipeline of the ambient temperature methanol washing tower via the flash vapor pipeline. The bottom of the flash evaporator is connected to the thermal regeneration tower. The bottom of the thermal regeneration tower is connected to the upper middle part of the low temperature methanol washing tower via the recycle pipeline of the thermal regeneration tower.
[0014] As a preferred embodiment, the recycle pipeline of the thermal regeneration tower is connected to the recycle pipeline via a methanol replenishment pipeline.
[0015] As a preferred embodiment, the wastewater extraction pipeline of the ammonia refining tower is connected to the wastewater extraction pipeline of the ammonia stripping tower.
[0016] As a preferred embodiment, the wastewater collection pipeline of the ammonia stripping tower is connected to the ammonia washing tower via a wastewater circulation pipeline, and a filter is installed on the wastewater circulation pipeline.
[0017] As a preferred embodiment, the top of the ammonia washing tower is connected to the ambient temperature methanol washing tower via a pipeline at the top of the ammonia washing tower, and a cooling device is installed on the pipeline at the top of the ammonia washing tower.
[0018] As a preferred embodiment, the cooling device includes a water cooling device and an ammonia cooling device connected in sequence.
[0019] As a preferred embodiment, a saturator is provided at the front of the cooling device.
[0020] As a preferred embodiment, the methanol water separator wastewater utilization pipeline is connected to one end of the wastewater utilization pipeline, and the other end of the wastewater utilization pipeline is connected to the upper part of the extraction tower.
[0021] As a preferred embodiment, a compressor and a condenser are installed on the top outlet pipeline of the ambient temperature methanol washing tower.
[0022] As a preferred embodiment, the condensation device includes a water cooler, a condenser, and an ammonia cooler connected in sequence.
[0023] As a preferred embodiment, the clean gas extraction pipeline is connected to the input and output ends of the condenser.
[0024] This application has the following advantages:
[0025] 1. The purification device of this application has a short process, requires less equipment and investment, and produces coke oven gas with high purification index that can be directly utilized;
[0026] 2. No waste liquid, waste residue, or waste catalyst; green and environmentally friendly.
[0027] 3. Low energy consumption;
[0028] 4. It can generate 20% ammonia water or liquid ammonia, resulting in high product value;
[0029] 5. Acidic gases can be used to produce sulfur or sulfuric acid through Claus, resulting in high-value products;
[0030] 6. Benzene removal is thorough, with a recovery rate of nearly 100%, resulting in high profits.
[0031] 7. This unit can use the residual pressure of the gas from the coke oven to drive the ammonia compression refrigeration in the expander, providing cooling for this unit and also providing some cooling to the outside world. Attached Figure Description
[0032] Figure 1 This is a schematic diagram of this application;
[0033] 1. Ammonia washing tower; 2. Feed pipeline; 3. Ammonia washing tower bottom pipeline; 4. Ammonia stripping tower; 5. Ammonia water pipeline; 6. Ammonia stripping tower wastewater collection pipeline; 7. Wastewater circulation pipeline; 8. Filter; 9. Ammonia stripping tower top pipeline; 10. Ammonia water refining tower; 11. Ammonia-containing material collection pipeline; 12. Ammonia water refining tower wastewater collection pipeline; 13. Ammonia washing tower top pipeline; 14. Ambient temperature methanol washing tower; 15. Water cooling unit; 16. Ammonia cooling unit; 17. Saturator; 18. Ambient temperature methanol washing tower bottom pipeline; 19. Extraction tower; 20. Oil collection pipeline; 21. Extraction tower bottom pipeline; 22. Methanol-water separation tower; 23. Extraction tower bottom heat exchanger one; 24. Extraction tower bottom heat exchanger two; 25. Methanol-water separation tower wastewater collection pipeline; 26. Wastewater utilization pipeline; 27. 28. Wastewater cooler; 29. Methanol-water separator top circulation pipeline; 30. Circulation pipeline; 31. Circulation pipeline water cooling device; 32. Circulation pipeline ammonia cooling device; 33. Reflux tank; 34. Reflux pump; 35. Ambient temperature methanol washing tower top outlet pipeline; 36. Low temperature methanol washing tower; 37. Compressor; 38. Water cooler; 39. Condenser; 40. Ammonia cooler; 41. Clean coal gas outlet pipeline; 42. Low temperature methanol washing tower bottom pipeline; 43. Flash evaporator; 44. Condensate pipeline; 45. Condensate air cooler; 46. Flash vapor pipeline; 47. Compressor I; 48. Flash evaporator bottom pipeline; 49. Thermal regeneration tower; 50. Flash evaporator bottom heat exchanger; 51. Acid gas outlet pipeline; 52. Thermal regeneration tower bottom circulation pipeline; 53. Condensate ammonia cooler; 54. Methanol makeup pipeline. Detailed Implementation
[0034] The following is in conjunction with the appendix Figure 1 The specific embodiments of this utility model will be described in detail below. It should be noted that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of this utility model. Example 1
[0035] This embodiment provides a purification device for coke oven gas, including a water-washed ammonia tower 1. A feed pipeline 2 is installed on one side of the water-washed ammonia tower 1. The coke oven gas first passes through a cooling and blowing section to separate tar and ammonia water. Then, it is pressurized by a blower and an electric tar remover removes tar entrainment. Afterward, the coke oven gas enters the water-washed ammonia tower 1 through the feed pipeline 2 for ammonia washing, reducing the ammonia content to below 2 PPM. The bottom of the water-washed ammonia tower 1 is connected to the upper part of an ammonia stripping tower 4 via a water-washed ammonia tower bottom pipeline 3. The water-washed ammonia tower bottom pipeline 3 is also connected to an ammonia water pipeline 5. The remaining ammonia water from the cooling and blowing section, along with the washing water from the water-washed ammonia tower 1, enters the ammonia stripping tower 4. The bottom of the ammonia stripping tower 4 is configured with... A wastewater collection pipeline 6 from the ammonia stripping tower is provided. Preferably, the wastewater collection pipeline 6 is connected to the ammonia washing tower 1 via a wastewater circulation pipeline 7. A filter 8 is installed on the wastewater circulation pipeline 7, and the filtered wastewater enters the ammonia washing tower 1 for further ammonia washing. The top of the ammonia stripping tower 4 is connected to the ammonia water refining tower 10 via a top pipeline 9. An ammonia-containing material collection pipeline 11 is provided on one side of the ammonia water refining tower 10, which collects pure ammonia gas or 20% ammonia water. The bottom of the ammonia water refining tower 10 is provided with an ammonia water refining tower wastewater collection pipeline 12. Preferably, the ammonia water refining tower wastewater collection pipeline 12 is connected to the wastewater collection pipeline 6 from the ammonia stripping tower.
[0036] The top of the ammonia washing tower 1 is connected to the ambient temperature methanol washing tower 14 via a top pipeline 13. A cooling device is installed on the top pipeline 13, which includes a water cooling device 15 and an ammonia cooling device 16 connected in sequence. Preferably, a saturator 17 is installed in front of the water cooling device 15 for fine washing and ammonia removal. When the ammonia washing tower 1 can meet the ammonia removal standard, there is no need to install the saturator 17. Technicians can make the appropriate settings according to the specific situation.
[0037] The bottom of the ambient temperature methanol washing tower 14 is connected to the extraction tower 19 via the ambient temperature methanol washing tower bottom pipeline 18. The top of the extraction tower 19 is equipped with an oil extraction pipeline 20, which is used to extract oily substances and some ammonia and sulfur from the coke oven gas. The bottom of the extraction tower 19 is connected to the methanol-water separation tower 22 via the extraction tower bottom pipeline 21. The extraction tower bottom pipeline 21 is equipped with an extraction tower bottom heat exchanger 23 and an extraction tower bottom heat exchanger 24. The bottom of the methanol-water separation tower 22 is connected to a methanol-water separation tower wastewater extraction pipeline 25. Preferably, the methanol-water separation tower wastewater outlet pipeline 25 passes through the extraction tower bottom heat exchanger 24 and exchanges heat with the extraction tower bottom heat exchanger 24. The wastewater after heat exchange is sent to biochemical treatment. Further, one end of the methanol-water separation tower wastewater outlet pipeline 25 is connected to the wastewater utilization pipeline 26, and the other end of the wastewater utilization pipeline 26 is connected to the upper part of the extraction tower 19. The wastewater utilization pipeline 26 is equipped with a wastewater cooler 27. Part of the wastewater collected from the methanol-water separation tower 22 enters the extraction tower 19 for further extraction, and part is directly sent to biochemical treatment.
[0038] The top of the methanol-water separator 22 is connected to the upper middle part of the methanol-water separator 22 via the top circulation pipeline 28. One end of the circulation pipeline 29 is connected to the top circulation pipeline 28, and the other end of the circulation pipeline 29 is connected to the ambient temperature methanol washing tower 14. A circulation pipeline cooling device is provided on the circulation pipeline 29. Further, the circulation pipeline cooling device includes a circulation pipeline water cooling device 30 and a circulation pipeline ammonia cooling device 31 connected in sequence. Both are commonly used cooling devices in the prior art. The different descriptions are to distinguish different installation positions. Preferably, the top circulation pipeline 28 of the methanol-water separator passes through the extraction tower bottom heat exchanger 23. A reflux tank 32 and a reflux pump 33 are also provided on the top circulation pipeline 28 of the methanol-water separator.
[0039] The top of the ambient temperature methanol washing tower 14 is connected to the low temperature methanol washing tower 35 via the ambient temperature methanol washing tower top outlet pipeline 34. The ambient temperature methanol washing tower top outlet pipeline 34 is equipped with a compressor 36 and a condensing device. The condensing device includes a water cooler 37, a condenser 38, and an ammonia cooler 39 connected in sequence. The top of the low temperature methanol washing tower 35 is equipped with a clean coal gas outlet pipeline 40. Preferably, the clean coal gas outlet pipeline 40 exchanges heat through the condenser 38, that is, the clean coal gas outlet pipeline 40 is connected to the input end and the output end of the condenser 38.
[0040] The bottom of the low-temperature methanol washing tower 35 is connected to the flash tower 42 via a low-temperature methanol washing tower bottom pipeline 41. A condensate air cooler 44 is installed on the low-temperature methanol washing tower bottom pipeline 41. Furthermore, the water cooler 37, condenser 38, and ammonia cooler 39 are all connected to a condensate pipeline 43, which is connected to the low-temperature methanol washing tower bottom pipeline 41. The top of the flash tower 42 is connected to the ambient temperature methanol washing tower top outlet pipeline 34 via a flash vapor pipeline 45. A compressor 46 is installed on the ambient temperature methanol washing tower top outlet pipeline 34. The bottom of the flash tower 42 is connected to the thermal regeneration tower 48 via a flash tower bottom pipeline 47. A flash evaporator reboiler heat exchanger 49 is installed on the reboiler pipeline 47. An acid gas extraction pipeline 50 is installed at the top of the thermal regeneration tower 48. The extracted acid gas is used to produce sulfur or sulfuric acid through Claus, resulting in high-value products. The bottom of the thermal regeneration tower 48 is connected to the upper middle part of the low-temperature methanol washing tower 35 through a thermal regeneration tower reboiler circulation pipeline 51. The thermal regeneration tower reboiler circulation pipeline 51 passes sequentially through the flash evaporator reboiler heat exchanger 49 and the condensate air cooler 44. Furthermore, a condensate ammonia cooler 52 is installed on the rear side of the condensate air cooler 44. The thermal regeneration tower reboiler circulation pipeline 51 is connected to the circulation pipeline 29 through a methanol replenishment pipeline 53 for methanol replenishment.
[0041] The specific working principle of this application is as follows:
[0042] The coke oven gas first passes through the cooling section to separate tar and ammonia water. After being pressurized by the blower and the tar entrainment removed by the electric tar replenisher, the coke oven gas enters the water washing ammonia tower 1 through the feed pipeline 2 for ammonia washing, reducing the ammonia content to below 2PPM.
[0043] The washing water from the bottom of the ammonia washing tower 1, along with the remaining ammonia water from the cooling drum section, enters the ammonia stripping tower 4 for ammonia stripping. The top of the ammonia stripping tower 4 produces approximately 10% ammonia water, which then enters the ammonia water refining tower 10 to separate acidic gas. This acidic gas is collected from the top of the ammonia water refining tower 10 and can be used to produce sulfur or sulfuric acid via Claus, resulting in high-value products. Ammonia vapor is collected from the side stream in the middle of the ammonia water refining tower 10 and undergoes multiple cooling and separation processes to obtain 20% refined ammonia water or further processed into liquid ammonia. The wastewater from the bottom of the ammonia stripping tower 4, after passing through filter 8, is partially recycled back to the ammonia washing tower 1 for ammonia washing, with the excess undergoing biochemical treatment.
[0044] After ammonia washing in the water-washing ammonia tower, the coke oven gas is cooled to about 5°C using water cooling device 15 and ammonia cooling device 16, and then enters the ambient temperature methanol washing tower 14. Methanol at 0-5°C is used for washing to remove oily substances and some ammonia and sulfur from the coke oven gas. The washed methanol enters the extraction tower 19 for extraction with water. The oily substances are removed from the top of the extraction tower 19 and sent to the tank area as crude benzene for external sale.
[0045] The methanol-water mixture at the bottom of extraction tower 19 enters methanol-water separation tower 22 to remove water. Methanol is used as a circulating washing liquid and exchanges heat with heat exchanger 23 at the bottom of extraction tower to cool down. Part of the methanol is returned to methanol-water separation tower 22 for use, and part is returned to room temperature methanol washing tower 14 for recycling. Part of the water collected from the bottom of methanol-water separation tower 22 is returned to extraction tower 19 for recycling as extraction water, and the excess is sent to biochemical treatment.
[0046] The coke oven gas, after being washed with methanol at room temperature in the ambient temperature methanol washing tower 14, is pressurized to 2.5 MPa in the compressor 36. The waste liquid from each stage of the separator in the compressor 36 is returned to the extraction tower 19. The pressurized coke oven gas is then cooled to about -25°C by the water cooler 37, condenser 38, and ammonia cooler 39, and then enters the low-temperature methanol washing tower 35 for washing to remove all other impurities from the coke oven gas, achieving the purification standards: total sulfur 0.1 ppm, ammonia content 0.1 ppm, and no oil. The coke oven gas after the low-temperature methanol washing can be directly supplied to downstream applications.
[0047] The methanol-rich solution washed in the low-temperature methanol washing tower 35 enters the flash tower 42 for flash evaporation, where some carbon dioxide is flashed out. After being compressed by the compressor 46, it is mixed with the coke oven gas from the top of the ambient temperature methanol washing tower 14 and then continues to be washed in the low-temperature methanol washing tower 35. The flash-evaporated rich methanol exchanges heat with the heat exchanger 49 at the bottom of the flash tower and then enters the thermal regeneration tower 48 for regeneration. The thermal regeneration tower 48 removes acidic gas, which is collected from the top of the thermal regeneration tower 48 and can be subsequently used to produce sulfur or sulfuric acid through Claus, resulting in high-value products. The regenerated methanol collected from the bottom of the thermal regeneration tower 48 exchanges heat and then enters the low-temperature methanol washing tower 35 for recycling.
[0048] In summary, due to the adoption of the above-mentioned technical solutions, this application has advantages over existing purification devices, including shorter purification processes, lower equipment investment, smaller footprint, and higher coke oven gas purification index that can be directly utilized. In addition, it also has the advantages of producing no waste liquid, waste residue, or waste catalyst, making it green and environmentally friendly; low energy consumption; more thorough benzene removal with a recovery rate of nearly 100%, and high profits.
[0049] The preferred embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this application, various simple modifications can be made to the technical solution of this application, and these simple modifications all fall within the protection scope of this application.
[0050] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable way without contradiction. In order to avoid unnecessary repetition, the various possible combinations in this application will not be described separately.
[0051] Furthermore, various different implementations of this application can be combined in any way, as long as they do not violate the spirit of this application, and such combinations should also be regarded as the content disclosed in this application.
Claims
1. A purification device for coke oven gas, comprising a water-washing ammonia tower (1), wherein a feed pipeline (2) is provided on one side of the water-washing ammonia tower (1), characterized in that, The bottom of the ammonia washing tower (1) is connected to the ammonia stripping tower (4); The bottom of the ammonia stripping tower (4) is equipped with an ammonia stripping tower wastewater outlet pipeline (6), the top of the ammonia stripping tower (4) is connected to the ammonia water refining tower (10), the ammonia water refining tower (10) is equipped with an ammonia-containing material outlet pipeline (11) on one side, and the bottom of the ammonia water refining tower (10) is equipped with an ammonia water refining tower wastewater outlet pipeline (12). The top of the water washing ammonia tower (1) is connected to the ambient temperature methanol washing tower (14), the bottom of the ambient temperature methanol washing tower (14) is connected to the extraction tower (19), the top of the extraction tower (19) is provided with an oil extraction pipeline (20), the bottom of the extraction tower (19) is connected to the methanol-water separation tower (22), the bottom of the methanol-water separation tower (22) is connected to the methanol-water separation tower wastewater extraction pipeline (25), the top of the methanol-water separation tower (22) is connected to the middle and upper part of the methanol-water separation tower (22) through the methanol-water separation tower top circulation pipeline (28), one end of the circulation pipeline (29) is connected to the methanol-water separator tower top circulation pipeline (28), and the other end of the circulation pipeline (29) is connected to the ambient temperature methanol washing tower (14). The top of the ambient temperature methanol washing tower (14) is connected to the low temperature methanol washing tower (35) via the ambient temperature methanol washing tower top outlet pipeline (34). The top of the low temperature methanol washing tower (35) is equipped with a clean coal gas outlet pipeline (40). The bottom of the low temperature methanol washing tower (35) is connected to the flash evaporator (42). The top of the flash evaporator (42) is connected to the ambient temperature methanol washing tower top outlet pipeline (34) via the flash vapor pipeline (45). The bottom of the flash evaporator (42) is connected to the thermal regeneration tower (48). The bottom of the thermal regeneration tower (48) is connected to the middle and upper part of the low temperature methanol washing tower (35) via the thermal regeneration tower bottom circulation pipeline (51).
2. The coke oven gas purification device according to claim 1, characterized in that, The recycle pipeline (51) of the thermal regeneration tower is connected to the recycle pipeline (29) via the methanol replenishment pipeline (53).
3. The coke oven gas purification device according to claim 1, characterized in that, The wastewater collection pipeline (6) of the ammonia stripping tower is connected to the ammonia washing tower (1) through the wastewater circulation pipeline (7), and a filter (8) is installed on the wastewater circulation pipeline (7).
4. The coke oven gas purification device according to claim 1, characterized in that, The ammonia refining tower wastewater collection pipeline (12) is connected to the ammonia stripping tower wastewater collection pipeline (6).
5. A coke oven gas purification device according to claim 1, characterized in that, The top of the ammonia washing tower (1) is connected to the ambient temperature methanol washing tower (14) via the top pipeline (13) of the ammonia washing tower. A cooling device is installed on the top pipeline (13) of the ammonia washing tower.
6. A coke oven gas purification device according to claim 5, characterized in that, A saturator (17) is provided at the front of the cooling device.
7. A coke oven gas purification device according to claim 1, characterized in that, The methanol water separator wastewater collection pipeline (25) is connected to one end of the wastewater utilization pipeline (26), and the other end of the wastewater utilization pipeline (26) is connected to the upper part of the extraction tower (19).
8. A coke oven gas purification device according to claim 1, characterized in that, A compressor (36) and a condenser are installed on the top outlet pipeline (34) of the ambient temperature methanol washing tower.
9. A coke oven gas purification device according to claim 8, characterized in that, The condensation device includes a water cooler (37), a condenser (38), and an ammonia cooler (39) connected in sequence.
10. A coke oven gas purification device according to claim 9, characterized in that, The clean gas extraction pipeline (40) is connected to the input and output ends of the condenser (38).