Coke oven gas desulfurization system

Abstract

The utility model discloses a coke oven gas desulfurization system which comprises an absorption tower, a desorption tower, heat exchange equipment, first cooling equipment, second cooling equipment and gas-liquid separation equipment, wherein the absorption tower is used for contact absorption reaction of coke oven gas and a composite alcohol amine solution to implement a desulfurization process; the desorption tower is connected with the absorption tower and is used for desorption reaction of desorbing the acid gas from the composite alcohol amine solution which absorbs the acid gas and providing circulating liquid for desulfurization reaction; the first input end of the heat exchange equipment is connected to the rich liquor output end of the absorption tower, and the second input end is connected with the barren liquor output end of the desorption tower; the second output end is connected to the input end of the first cooling equipment, and the output end of the first cooling equipment is connected to the top input end of the desulfurizing tower; the input end of the second cooling equipment is connected to the acid gas output end at the top of the desorption tower, and liquid generated by the second cooling equipment and the gas-liquid separator is connected to the top of the desorption tower through a pipeline; the gas-liquid separation equipment is used for separating acid gas from water vapor.

Description

Technical Field

[0001] The utility model relates to the technical field of coke oven gas desulfurization, in particular to a coke oven gas desulfurization system. Background Art

[0002] At present, coke oven gas purification mostly adopts two-stage desulfurization or three-stage desulfurization, and the last stage is desulfurization with dry desulfurizer to meet the user's demand for gas quality. However, the dry desulfurizer after absorbing H2S, HCN, and organic sulfur saturation enters the subsequent user such as sintering process. After combustion, the SO2 content in the sintering flue gas increases, which increases the difficulty of meeting the waste gas emission standards of the sintering process, does not meet the requirements of environmental protection, and cannot reduce the hydrogen sulfide content of coke oven gas from the source.

[0003] In order to reduce SO2 pollution to the atmosphere and prevent harmful substances such as H2S, HCN, and organic sulfur in coke oven gas from affecting the quality of steel products or the quality of subsequent hydrogen production and methanol products, it is necessary to remove H2S, HCN, and organic sulfur contained in coke oven gas. The H2S, HCN, and organic sulfur content of the gas exported by the coking plant after purification is high, which cannot effectively meet the quality and environmental protection emission requirements of subsequent steel rolling, hydrogen production, methanol production, etc. Utility Model Content

[0004] In order to solve some or all of the technical problems existing in the above-mentioned prior art, the utility model provides a coke oven gas desulfurization system, which has high desulfurization efficiency, low corrosion to equipment, good stability, low thermal degradation, and is easy to recover from contaminated solutions. It can circulate desulfurization, can greatly reduce SO2 pollution to the atmosphere, and prevent harmful impurities such as H2S and HCN in coke oven gas from affecting the quality of subsequent products. In particular, desulfurization facilities are constructed for coke oven gas produced by coke ovens in coking plants, which are used to more efficiently remove H2S, HCN, organic sulfur, etc. in coke oven gas.

[0005] The technical solution of the utility model is as follows:

[0006] The utility model provides a coke oven gas desulfurization system, comprising:

[0007] An absorption tower, wherein a composite alcohol amine solution spraying channel is provided in the absorption tower, a desulfurization process is implemented in the absorption tower, and the external coke oven gas is contacted with the sprayed composite alcohol amine solution to perform an absorption reaction;

[0008] A desorption tower, which is used for desorption reaction of acid gas from the composite alcohol amine solution and provides circulating liquid for desulfurization reaction;

[0009] A heat exchange device, wherein the first input end of the heat exchange device is connected to the first output end of the absorption tower, and the second input end of the heat exchange device is connected to the second output end of the analysis tower, and is used to heat the rich liquid at the bottom of the absorption tower and the circulating liquid flowing out of the analysis tower in the heat exchange device for heating, and then reflux to the analysis tower through the first output end of the heat exchange device for regeneration after heat exchange; at the same time, the lean liquid analyzed by the analysis tower is cooled, and then sent to the top of the absorption tower after heat exchange with chilled water by the first cooling device;

[0010] A first cooling device, wherein the input end of the first cooling device is connected to the second output end of the heat exchange device, and the output end of the first cooling device is connected to the upper input end of the desulfurization tower, and is used to heat the circulating liquid flowing out of the analysis tower with the rich liquid connected to the bottom of the absorption tower in the heat exchange device, and then heat exchange and cool it in the first cooling device, and then send it to the top of the absorption tower, and then pass through the absorption tower from top to bottom for desulfurization absorption reaction;

[0011] A second cooling device, wherein the input end of the second cooling device is connected to the top output end of the analytical tower, the output end of the second cooling device is connected to the top input end of the analytical tower through a first output pipeline, and the output end of the second cooling device is connected to the input end of the gas-liquid separation device through a second output pipeline, for cooling the acid gas and water vapor outputted from the analytical tower;

[0012] A gas-liquid separation device is used to separate the acid gas and water vapor input by the second cooling device, and input the separated clean coke oven gas into an external clean gas main pipe, input the separated acid gas into an external acid gas main pipe for acid production, and reflux the separated liquid to the top input pipe of the analysis tower to enter the analysis tower for regeneration.

[0013] Furthermore, in the above-mentioned coke oven gas desulfurization system, the first cooling device is a cooler.

[0014] Furthermore, in the above-mentioned coke oven gas desulfurization system, the heat exchange equipment is a heat exchanger.

[0015] Furthermore, in the above-mentioned coke oven gas desulfurization system, the heat exchange equipment is a spiral heat exchanger.

[0016] Furthermore, in the above-mentioned coke oven gas desulfurization system, the second cooling equipment includes three-stage coolers connected in sequence, which are used to cool the mixed gas of acid gas and water vapor output from the top of the decomposition tower through an air cooler for primary cooling, and then enter the condenser cooler after primary cooling in the air cooler, and use circulating water for secondary cooling in the condenser cooler, and then enter the chilled water cooler for tertiary cooling after secondary cooling.

[0017] Furthermore, in the above-mentioned coke oven gas desulfurization system, a reboiler is arranged on the analysis tower, which is used to pass the excess rich liquid from top to bottom through the analysis tower to countercurrently contact with the gas generated by the reboiler, so that the acid gas is evaporated from the rich liquid.

[0018] Furthermore, in the above-mentioned coke oven gas desulfurization system, a reflux tank is provided between the second cooling device and the analysis tower for storing the liquid cooled by the second cooling device and the liquid separated by the gas-liquid separation device.

[0019] Furthermore, in the above-mentioned coke oven gas desulfurization system, the heat exchange equipment is a heat exchanger made of stainless steel.

[0020] The main advantages of the technical solution of this utility model are as follows:

[0021] The coke oven gas desulfurization system of the utility model is to introduce the coke oven gas to be purified and the circulating liquid into the absorption tower for reaction to generate rich liquid, and under the conditions of heat exchange heating and cooling of the heat exchange equipment, the rich liquid generated after the reaction of the coke oven gas and the circulating liquid is refluxed to the analysis tower for analysis and regeneration, and acidic gas and water vapor are analyzed, and the regenerated circulating liquid is introduced into the absorption tower for reaction, forming a cycle of circulating liquid regeneration and desulfurization reaction, avoiding the discharge pollution and waste of the circulating liquid, and reducing the preparation process of the circulating liquid; through the cooling of the second cooling device, the mixed gas of the acidic gas and water vapor analyzed at the top of the analysis tower is cooled and separated, so as to achieve the purpose of separation and desulfurization. The desulfurization efficiency is fast, the corrosion to the equipment is small, the stability is good, the thermal degradation is small, it is easy to recover from the contaminated solution, and it can be cyclically desulfurized, which can greatly reduce the pollution of SO2 to the atmosphere and prevent the harmful impurities such as H2S and HCN in the coke oven gas from affecting the quality of subsequent products. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings described herein are used to provide a further understanding of the embodiments of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0023] Figure 1 This is a schematic structural diagram of a coke oven gas desulfurization system according to an embodiment of the utility model;

[0024] Description of reference numerals:

[0025] 1. Absorption tower; 2. Gas-liquid separation equipment; 3. Analysis tower; 4. Heat exchange equipment; 5. First cooling equipment; 6. Second cooling equipment; 7. Reboiler; 8. Reflux tank. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the utility model clearer, the technical solution of the utility model will be clearly and completely described below in combination with the specific embodiments of the utility model and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0027] The technical solution provided by the embodiment of the utility model is described in detail below in conjunction with the accompanying drawings.

[0028] As attached Figure 1 As shown, the embodiment of the utility model provides a coke oven gas desulfurization system, which includes an absorption tower 1, a desorption tower 3, a heat exchange device 4, a first cooling device 5, a second cooling device 6 and a gas-liquid separation device 2, wherein:

[0029] A composite alcohol amine solution spraying channel is provided in the absorption tower 1, which is used to contact the external coke oven gas with the sprayed composite alcohol amine solution to carry out an absorption reaction, implement a desulfurization process in the desulfurization tower 1, and carry out a desulfurization reaction; the first output end of the analysis tower 3 is connected to the absorption tower 1, which is used for analyzing the acid gas from the composite alcohol amine solution and providing a circulating liquid for the desulfurization reaction; the first input end of the heat exchange device 4 is connected to the first output end of the absorption tower 1, and the second input end of the heat exchange device 4 is connected to the second output end of the analysis tower 3, which is used to heat exchange and heat up the rich liquid at the bottom of the absorption tower 1 with the circulating liquid flowing out of the analysis tower 3 in the heat exchange device 4, and after heat exchange and heating, it flows back to the analysis tower 3 through the first output end of the heat exchange device 4 for analysis and regeneration, and at the same time, the lean liquid analyzed by the analysis tower 3 is cooled, and then sent to the top of the absorption tower 1 after heat exchange and cooling with chilled water by the first cooling device 5; the input end of the first cooling device 5 is connected to the second output end of the heat exchange device 4, and the first cooling device 5 The output end is connected to the upper input end of the absorption tower 1, and is used to send the circulating liquid flowing out of the analysis tower 3 to the top of the absorption tower 1 after heat exchange and cooling with the rich liquid connected to the bottom of the absorption tower 1 in the heat exchange device 4, and then to the first cooling device 5 after heat exchange and cooling, and to carry out desulfurization absorption reaction from top to bottom through the absorption tower 1; the input end of the second cooling device 6 is connected to the top output end of the analysis tower 3, the output end of the second cooling device 6 is connected to the top input end of the analysis tower 3 through the first output pipeline, and the output end of the second cooling device 6 is connected to the input end of the gas-liquid separation device 2 through the second output pipeline, which is used to cool the acid gas and water vapor output by the analysis tower 3; the gas-liquid separation device 2 is used to separate the acid gas and water vapor input by the second cooling device 6, and input the separated clean coke oven gas into the external clean gas main pipe, input the separated acid gas into the external acid gas main pipe for acid production, and reflux the separated liquid to the top input pipe of the analysis tower 3, and enter the analysis tower 3 for regeneration.

[0030] The desulfurization principle of the coke oven gas desulfurization system of the utility model is:

[0031] The coke oven gas to be purified is introduced into the absorption tower 1 from the bottom of the absorption tower 1, passes through the absorption tower 1 from bottom to top, and contacts with the circulating liquid sprayed into the absorption tower 1 in countercurrent. The acid gas in the coke oven gas is absorbed by the circulating liquid and purified. The purified gas is drawn out from the top of the tower, and enters the clean gas main after most of the water carried is removed by the gas-liquid separation equipment. The circulating liquid sprayed into the absorption tower 1 for desulfurization reaction is the circulating solution after desorption in the analysis tower 3. The lean amine liquid coming out of the upper and lower sections of the analysis tower 3 is cooled by heat exchange with the rich liquid connected to the bottom of the absorption tower 1 through the heat exchange equipment 4, and then cooled by heat exchange with chilled water through the first cooling equipment 5, and then sent to the top of the absorption tower 1, passing through the absorption tower 1 from top to bottom to carry out the desulfurization absorption reaction. The rich liquid flowing out from the bottom of the absorption tower 1 is heated by heat exchange with the lean amine liquid through the heat exchange equipment 4, and then enters the top of the analysis tower 3 for desorption and regeneration. Part of the absorbed acidic gas will flash out from the hot rich liquid on the tower plate at the top of the analysis tower 3, and the remaining rich liquid will be countercurrently contacted with the gas produced by the reboiler 7 through the analysis tower 3 from top to bottom, so that the acidic gas will be evaporated from the rich liquid; the mixed gas of the acidic gas and water vapor coming out of the top of the analysis tower 3 will be cooled by the second cooling device 6, and the cooled liquid and the liquid separated by the gas-liquid separation device 2 will be transported to the rich liquid main pipe for regeneration at the top of the analysis tower 3 through a reflux pump, and then enter the top of the analysis tower 3 for regeneration, and the above-mentioned desulfurization reaction will be circulated until the coke oven gas to be purified is completely purified and separated.

[0032] With such arrangement, the coke oven gas desulfurization system of the utility model has high desulfurization efficiency, low corrosion to equipment, good stability, low thermal degradation, easy recovery from contaminated solution, and can circulate desulfurization, which can greatly reduce the pollution of SO2 to the atmosphere and prevent the harmful impurities such as H2S, HCN, organic sulfur in the coke oven gas from affecting the quality of subsequent products. Specifically, the coke oven gas to be purified and the circulating liquid are introduced into the absorption tower 1 for reaction to generate rich liquid, and the rich liquid generated after the reaction of the coke oven gas and the circulating liquid is refluxed to the analysis tower 3 for analysis and regeneration under the heat exchange heating and cooling of the heat exchange equipment 4, and the regenerated circulating liquid is introduced into the absorption tower 1 for reaction, forming a cycle of the circulating liquid regeneration reaction, avoiding the discharge pollution and waste of the circulating liquid, and reducing the preparation of the circulating liquid; the mixed gas of the acid gas and water vapor evaporated from the top of the analysis tower 3 is cooled and separated by the cooling of the second cooling device 6, so as to achieve the purpose of separation and desulfurization.

[0033] At the same time, in the coke oven gas desulfurization system of the utility model, the recovery of the coke oven gas to be desulfurized in the absorption tower 1, such as hydrogen sulfide in the coke oven gas, and the regeneration of the solution in the desorption tower are divided into two stages, thereby improving the desulfurization and circulating liquid regeneration efficiency. By continuously adding fresh circulating liquid and steam condensate or desalted water to the existing circulating solution, the stability and balance of the circulating liquid volume of the desulfurization system are maintained, so that the desulfurization reaction can be carried out continuously and stably.

[0034] Preferably, in the coke oven gas desulfurization system of the present invention, the first cooling device 5 is a cooler.

[0035] Preferably, in the coke oven gas desulfurization system of the present invention, the gas-liquid separation device 2 is a gas-liquid separator.

[0036] Specifically, in the coke oven gas desulfurization system of the present invention, the heat exchange device 4 is a heat exchanger; preferably, the heat exchange device 4 is a spiral heat exchanger; most preferably, the heat exchange device 4 is a heat exchanger made of stainless steel, such as a spiral heat exchanger made of stainless steel 2205.

[0037] In this way, the heating / cooling circulating fluid exchanges heat in the stainless steel 2205 spiral heat exchanger, which has high heat exchange efficiency and long equipment life. The second cooling device of the regenerated circulating fluid uses chilled water as the medium for cooling. The cooler is small in size and has a good cooling effect.

[0038] Specifically, in the coke oven gas desulfurization system of the present invention, the second cooling equipment includes three-stage coolers connected in sequence, which are used to cool the mixed gas of acid gas and water vapor output from the top of the analysis tower 3 through an air cooler for primary cooling, and then enter the condenser cooler after primary cooling in the air cooler, and use circulating water for secondary cooling in the condenser cooler, and then enter the chilled water cooler for tertiary cooling after secondary cooling.

[0039] In some optional implementations of the present embodiment, the mixed gas of acid gas and water vapor coming out from the top of the desorption tower is first cooled by 6 air coolers, and the acid gas cooled by the air cooler then enters the condenser cooler, undergoes secondary cooling in the circulating water cooler, and then enters the chilled water cooler for tertiary cooling. After cooling, the acid gas enters the gas-liquid separator for further separation of water, and is then sent to the acid production process through the acid gas main line for acid production.

[0040] With this arrangement, the flash gas of the steam-acid gas mixture at the outlet of the desorption tower is first cooled by the air cooler and then cooled by circulating water and chilled water in the condenser cooler for the second and third stages, thus ensuring the cooling effect while saving energy.

[0041] Specifically, in the coke oven gas desulfurization system of the present invention, a reboiler 7 is further provided on the analysis tower 3, for countercurrently contacting the excess rich liquid with the gas generated by the reboiler 7 from top to bottom through the analysis tower 3, so that the acid gas is evaporated from the rich liquid.

[0042] With such arrangement, since part of the absorbed acidic gas will flash out from the hot rich liquid on the tower plate at the top of the desorption tower, the remaining rich liquid can be countercurrently contacted with the gas generated by the reboiler 7 from top to bottom through the desorption tower, so that the acidic gas is evaporated from the rich liquid, thereby making the removal of the acidic gas more thorough.

[0043] Specifically, in the coke oven gas desulfurization system of the present invention, a reflux tank 8 is provided between the second cooling device 6 and the analysis tower 3 for storing the liquid cooled by the second cooling device 6 and the liquid separated by the gas-liquid separation device 2 .

[0044] Such arrangement enables the liquid cooled by the second cooling device 6 and the liquid separated by the gas-liquid separation device 2 to be buffered in the reflux tank 8, thereby avoiding excessive circulating liquid in the analysis tower 3 caused by excessive liquid cooled or excessive liquid separated, causing the concentration of the circulating liquid to change, thereby avoiding the problems of insufficient and incomplete desulfurization reaction and poor desulfurization effect.

[0045] Specifically, in order to better illustrate how the coke oven gas desulfurization system of the present invention removes H2S, HCN and organic sulfur contained in the coke oven gas, an exemplary description is given below:

[0046] A circulating liquid is introduced into the analysis tower 3, and the coke oven gas to be purified is introduced into the absorption tower 1, and the circulating liquid in the analysis tower 3 is introduced into the absorption tower 1 to react with the coke oven gas for desulfurization to generate a rich liquid; the rich liquid at the bottom of the absorption tower 1 and the circulating liquid flowing out of the analysis tower 3 are heat exchanged and heated in the heat exchange device 4, and after the heat exchange and heating, they are refluxed to the analysis tower 3 through the first output end of the heat exchange device 4 for analysis and regeneration; the circulating liquid flowing out of the analysis tower 3 is heat exchanged and cooled with the rich liquid connected to the bottom of the absorption tower 1 in the heat exchange device 4, and then heat exchanged and cooled in the first cooling device 5, and then sent to the upper part of the absorption tower 1, and from top to bottom through the absorption tower 1, the rich liquid at the bottom of the absorption tower 1 is heat exchanged and cooled in the first cooling device 5, and then sent to the upper part of the absorption tower 1, and then the rich liquid at the bottom of the absorption tower 1 is heat exchanged and cooled in the first cooling device 5, and then the rich liquid at the bottom of the absorption tower 1 is heat exchanged and cooled in the absorption tower 1 ... Tower 1 performs desulfurization absorption reaction; the excess rich liquid in the absorption tower 1 passes through the analysis tower 3 from top to bottom, and contacts with the gas generated by the reboiler 7 on the analysis tower 3 in countercurrent flow, so that the acid gas is evaporated from the rich liquid; the acid gas and water vapor output by the analysis tower 3 are cooled and separated, the separated clean coke oven gas is input into the external clean gas main pipe, the separated acid gas is input into the external acid gas main pipe for acid production, and the separated liquid is refluxed and transported to the top input pipe of the analysis tower 3, and enters the analysis tower 3 for regeneration; the desulfurization reaction is circulated to the cooling and separation reaction until the coke oven gas to be purified is completely purified and separated.

[0047] Thus arranged, the coke oven gas desulfurization system of the utility model generates rich liquid by introducing the coke oven gas to be purified and the circulating liquid into the absorption tower 1 for reaction, and returns the rich liquid generated after the reaction of the coke oven gas and the circulating liquid to the analysis tower 3 for analysis and regeneration under the heat exchange heating and cooling of the heat exchange equipment 4, and introduces the regenerated circulating liquid into the absorption tower 1 for reaction, thus forming a cycle of the circulating liquid regeneration reaction, avoiding the discharge pollution and waste of the circulating liquid, and reducing the preparation of the circulating liquid; through the cooling of the second cooling equipment 6, the mixed gas of the acid gas and water vapor evaporated from the top of the analysis tower 3 is cooled and separated, so as to achieve the purpose of separation and desulfurization, which can greatly reduce the pollution of SO2 to the atmosphere and prevent the influence of harmful impurities such as H2S, HCN, organic sulfur in the coke oven gas on the quality of subsequent products.

[0048] In some optional implementations of this embodiment, the circulating liquid includes a complex alcohol amine aqueous solution with a concentration of 15%-45%.

[0049] With such arrangement, the utility model adopts the composite alcoholamine aqueous solution to carry out the desulfurization reaction. On the one hand, the composite alcoholamine desulfurization method has a simple and reliable process, the desulfurizer is cheap and easy to obtain, and the composite alcoholamine reacts with acidic gases such as hydrogen sulfide at the fastest speed, has a high desulfurization efficiency, has little corrosion to equipment, and has the advantages of stability, little thermal degradation, and easy recovery from contaminated solutions. On the other hand, the composite alcoholamine aqueous solution is alkaline and has a strong absorption capacity for acidic gases H2S and CO2. In particular, when the temperature is 25 to 40°C, the composite alcoholamine aqueous solution interacts with the acidic gas to generate salts. When the temperature is higher than 105°C, the generated amine sulfides and amine carbonates decompose, and the acidic gas is released from the saturated solution. The regenerated composite alcoholamine aqueous solution is cooled and recycled, and the acidic gas is sent to the acid-making process for acid-making, so there is no waste of the generated products and no pollution to the environment.

[0050] Therefore, the coke oven gas desulfurization system of the utility model and the coke oven gas desulfurization system using the same realizes that the concentration of hydrogen sulfide in the coke oven gas produced by the coke oven is reduced from ≤7.5g / Nm 3 Reduced to ≤20mg / Nm 3 , total sulfur ≤ 100mg / Nm 3 It can greatly reduce the pollution of SO2 to the atmosphere and prevent harmful impurities such as H2S, HCN, organic sulfur in coke oven gas from affecting the quality of subsequent products.

[0051] At the same time, in the coke oven gas desulfurization system provided by the utility model, in order to reduce the consumption of the composite alcohol amine aqueous solution and the amount of residual liquid produced, the process flow also needs to meet the following process conditions:

[0052] (1) The oxygen content of coke oven gas must be controlled to be no more than 0.2-0.3%.

[0053] (2) The complex alcohol amine is stored in nitrogen to avoid evaporation loss.

[0054] (3) A gas-liquid separator is installed at the clean gas outlet of absorption tower 1 to recover the complex alcohol amine solution carried by the gas.

[0055] (4) All pumps using complex alcohol amine solutions must be equipped with end seals to reduce leakage.

[0056] (5) The acid gas is cooled in three stages and a gas-liquid separator is installed.

[0057] (6) Adding sodium hydroxide to the tar separator to decompose the fixed salt to extract the complex alcohol amine.

[0058] (7) The process of desulfurization from coke oven gas is divided into two stages of absorption in the absorption tower 1, which is absorbed by a composite alcohol amine aqueous solution with a mass content of 15%-45%.

[0059] Specifically, since the absorption reaction is an exothermic reaction, the solution and coke oven gas are heated in the absorption tower 1. The complex alcohol amine compound produced by the reaction with H2S and CO2 is unstable. When the complex alcohol amine compound solution after absorption is heated to 105°C or above, the reaction is reversed. In the desorption tower, the complex alcohol amine compound is decomposed into H2S+CO2+complex alcohol amine. In addition to the formation of renewable compounds such as hydrogen sulfide and hydrogen cyanide in the desulfurization, compounds with sufficient thermal stability are also formed. In order to reduce the loss of complex alcohol amines in the regenerated solution and eliminate the accumulated thermally stable compounds in the solution, part of the circulating solution is continuously discharged to the tar separator, and sodium hydroxide is supplied to the tar separator. In the tar separator, non-renewable compounds react with sodium hydroxide to generate sodium salts and complex alcohol amines.

[0060] In some optional embodiments of the utility model, the acid gas after desulfurization adopts a wet acid production process to produce concentrated sulfuric acid, and the concentrated sulfuric acid is temporarily stored in a concentrated sulfuric acid tank in the tank area; the concentrated sulfuric acid is used as a production raw material to supply the ammonium sulfate section of the coking plant, and the final product is ammonium sulfate. The desulfurizer adopts a finished product of a composite alcohol amine. The waste residue and waste liquid generated by the desulfurization system are collected by a residual liquid tank, and are regularly pumped from the residual liquid tank to a loading truck and transported to the briquette process to make briquette coal, and then put into the furnace for coking. No waste residue is discharged, and no solid waste is discharged from the factory, so as not to cause secondary pollution to the environment. Part of the circulating solution is continuously taken out to the tar separator to react with the injected NaOH alkali solution to remove non-renewable composite alcohol amine compounds and hydrogen cyanide. The water and composite alcohol amine removed from the tar separator are supplemented to the composite alcohol amine circulating solution, so as to minimize the consumption of composite alcohol amines, and continuously discharge the waste from the tar separator to the residual liquid collection tank. The liquid condensed during the cooling process of the flashed acid gas flows back to the condensate collection tank, and then continuously supplied to the top of the desorption tower by the reflux pump. In the event of an accident, the acid gas is discharged to the coke oven gas pipeline behind the absorption tower 1.

[0061] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In addition, "front", "back", "left", "right", "upper" and "lower" in this article are all referenced to the placement state shown in the accompanying drawings.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A coke oven gas desulfurization system, characterized in that: include: An absorption tower, wherein a composite alcohol amine solution spraying channel is provided in the absorption tower, a desulfurization process is implemented in the absorption tower, and the external coke oven gas is contacted with the sprayed composite alcohol amine solution to perform an absorption reaction; A desorption tower, which is used for desorption reaction of acid gas from the composite alcohol amine solution and provides circulating liquid for desulfurization reaction; A heat exchange device, wherein the first input end of the heat exchange device is connected to the first output end of the absorption tower, and the second input end of the heat exchange device is connected to the second output end of the analysis tower, and is used to heat the rich liquid at the bottom of the absorption tower and the circulating liquid flowing out of the analysis tower in the heat exchange device for heating, and then reflux to the analysis tower through the first output end of the heat exchange device for regeneration after heat exchange; at the same time, the lean liquid analyzed by the analysis tower is cooled, and then sent to the top of the absorption tower after heat exchange with chilled water by the first cooling device; A first cooling device, wherein the input end of the first cooling device is connected to the second output end of the heat exchange device, and the output end of the first cooling device is connected to the upper input end of the desulfurization tower, and is used to heat the circulating liquid flowing out of the analysis tower with the rich liquid connected to the bottom of the absorption tower in the heat exchange device, and then heat exchange and cool it in the first cooling device, and then send it to the top of the absorption tower, and then pass through the absorption tower from top to bottom for desulfurization absorption reaction; A second cooling device, wherein the input end of the second cooling device is connected to the top output end of the analytical tower, the output end of the second cooling device is connected to the top input end of the analytical tower through a first output pipeline, and the output end of the second cooling device is connected to the input end of the gas-liquid separation device through a second output pipeline, for cooling the acid gas and water vapor outputted from the analytical tower; A gas-liquid separation device is used to separate the acid gas and water vapor input by the second cooling device, and input the separated clean coke oven gas into an external clean gas main pipe, input the separated acid gas into an external acid gas main pipe for acid production, and reflux the separated liquid to the top input pipe of the analysis tower to enter the analysis tower for regeneration.

2. The coke oven gas desulfurization system according to claim 1, characterized in that: The first cooling device is a cooler.

3. The coke oven gas desulfurization system according to claim 1, characterized in that: The heat exchange device is a heat exchanger.

4. The coke oven gas desulfurization system according to any one of claims 1 or 3, characterized in that: The heat exchange device is a spiral heat exchanger.

5. The coke oven gas desulfurization system according to claim 1, characterized in that: The second cooling device includes three-stage coolers connected in sequence, which are used to cool the mixed gas of acid gas and water vapor output from the top of the analysis tower through an air cooler for primary cooling, and then enter the condenser cooler after primary cooling in the air cooler, and use circulating water in the condenser cooler for secondary cooling, and then enter the chilled water cooler for tertiary cooling after secondary cooling.

6. The coke oven gas desulfurization system according to any one of claims 1 or 5, characterized in that: A reboiler is arranged on the analysis tower, and is used to pass the excess rich liquid from top to bottom through the analysis tower to countercurrently contact with the gas generated by the reboiler, so that the acid gas is evaporated from the rich liquid.

7. The coke oven gas desulfurization system according to claim 1, characterized in that: A reflux tank is provided between the second cooling device and the analytical tower for storing the liquid cooled by the second cooling device and the liquid separated by the gas-liquid separation device.

8. The coke oven gas desulfurization system according to any one of claims 1 or 3, characterized in that: The heat exchange equipment is a heat exchanger made of stainless steel.

Images