CN215403099U - Production system for preparing sulfuric acid from coke oven gas desulfurization waste liquid and sulfur foam - Google Patents
Production system for preparing sulfuric acid from coke oven gas desulfurization waste liquid and sulfur foam Download PDFInfo
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- CN215403099U CN215403099U CN202121263034.1U CN202121263034U CN215403099U CN 215403099 U CN215403099 U CN 215403099U CN 202121263034 U CN202121263034 U CN 202121263034U CN 215403099 U CN215403099 U CN 215403099U
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Abstract
The utility model relates to the technical field of chemical equipment, in particular to a production system for preparing sulfuric acid from desulfurization waste liquid and sulfur foam of coke oven gas, which comprises a pretreatment working section, an incineration working section, a purification working section, a conversion working section, a dry absorption working section and a tail gas treatment working section, wherein the pretreatment working section comprises a dilute sulfur foam tank and a microporous filter, a waste liquid input pipeline is arranged on the dilute sulfur foam tank, the upper part of the microporous filter is connected with a clear liquid tank through a clear liquid conveying pipe, the lower part of the microporous filter is connected with a concentrated sulfur foam tank through a concentrated sulfur conveying pipe, and the concentrated sulfur foam tank is connected with the incineration working section through a first conveying pipeline. The production system for preparing the sulfuric acid from the coke oven gas desulfurization waste liquid and the sulfur foam is convenient for recycling and regenerating the clean coke oven gas desulfurization waste liquid, can effectively save fossil energy, reduces the discharge amount of combustion waste gas, and remarkably improves the comprehensive economic benefit.
Description
Technical Field
The utility model relates to the technical field of chemical equipment, in particular to a production system for preparing sulfuric acid from coke oven gas desulfurization waste liquid and sulfur foam.
Background
The main processing method of coal is high-temperature coking and chemical product recovery, so the coking industry is an important part of the coal industry. The coke product can be used as fuel for blast furnace smelting, and can also be used for smelting with casting and non-ferrous metals and producing water gas; can be used for manufacturing producer gas for producing synthetic ammonia and can also be used for manufacturing calcium carbide so as to obtain raw materials of organic synthesis industry. The chemical products generated in the coking process can be used for preparing benzene, toluene, xylene, carbon disulfide and the like after recovery, processing and extraction of products such as tar, ammonia, naphthalene, hydrogen sulfide, crude benzene and the like, and refining processing and deep processing of pure coke oven gas, coal tar and crude benzene are obtained. The purified coke oven gas can be used as civil and industrial fuel. The ammonia in the coal gas can be used for preparing ammonium sulfate, concentrated ammonia water, anhydrous ammonia and the like.
The raw gas at the outlet of the coke oven contains a large amount of harmful components in the coking process, wherein H2S gas is also one of the harmful components. The raw coke oven gas is purified and washed to obtain the product clean coke oven gas after a series of treatments, sulfur foam and desulfurization waste liquid are generated in the ammonia desulfurization process of the gas, and the sulfur foam and the desulfurization waste liquid are always the problems of headache in the coking production and need to be solved urgently. The desulfurization waste liquid and sulfur foam generated by coal gas desulfurization in the coking industry are generally melted and solidified into massive sulfur for sale, and the sulfur has low purity, the sulfur content is about 60 percent, more impurities are generated, and the sulfur is difficult to receive in the market.
SUMMERY OF THE UTILITY MODEL
In order to solve the technical problems, the utility model aims to provide a production system for preparing sulfuric acid from coke oven gas desulfurization waste liquid and sulfur foam, which is convenient for recovering and regenerating the clean coke oven gas desulfurization waste liquid, can effectively save fossil energy, reduce the discharge amount of combustion waste gas and obviously improve the comprehensive economic benefit.
In order to achieve the technical effect, the utility model adopts the following technical scheme:
a production system for preparing sulfuric acid from coke oven gas desulfurization waste liquid and sulfur foam comprises a pretreatment working section, an incineration working section, a purification working section, a conversion working section, a dry absorption working section and a tail gas treatment working section, wherein the pretreatment working section comprises a dilute sulfur foam tank and a microporous filter, a waste liquid input pipeline is arranged on the dilute sulfur foam tank, the upper part of the microporous filter is connected with a clear liquid tank through a clear liquid conveying pipe, the lower part of the microporous filter is connected with a concentrated sulfur foam tank through a concentrated sulfur conveying pipe, the concentrated sulfur foam tank is connected with the incineration working section through a first conveying pipe, and the incineration working section is connected with the purification working section through a second conveying pipe; the dry absorption working section comprises a sulfuric acid drying tower and a sulfuric acid absorption tower, the purification working section is connected with the sulfuric acid drying tower through a third conveying pipeline, the sulfuric acid drying tower is connected with the conversion working section through a fourth conveying pipeline, the conversion working section is connected with the sulfuric acid absorption tower through a fifth conveying pipeline, and the sulfuric acid absorption tower is connected with the tail gas treatment working section through a sixth conveying pipeline.
Further, the pretreatment working section further comprises an effect separator, the clear liquid tank is communicated with the effect separator through a liquid separating pipeline, the effect separator is further connected with a steam heater through a forced circulation pipeline, a forced circulation pump is arranged on the forced circulation pipeline, a steam output pipe is further arranged at the top end of the effect separator, and a condenser is arranged at the tail end of the steam output pipe.
Furthermore, still be provided with the discharging pipe on the separator is imitated to one and just the separator is imitated to one and passes through discharging pipe and dense sulphur foam groove intercommunication, be provided with the circulation discharge pump on the discharging pipe.
Furthermore, a clear liquid return pipe is arranged on the clear liquid tank, and a clear liquid pump is arranged on the clear liquid return pipe.
Further, the incineration section comprises an incinerator, the first conveying pipeline is communicated with the incinerator, a waste heat boiler, a secondary air preheater and a primary air preheater are sequentially arranged at the lower reaches of the incinerator, and the primary air preheater is communicated with the purification section through a second conveying pipeline.
Compared with the prior art, the utility model has the beneficial effects that: the production system for preparing the sulfuric acid from the coke oven gas desulfurization waste liquid and the sulfur foam provided by the utility model can be used for firstly separating the coke oven gas desulfurization waste liquid and the sulfur foam to form clear liquid and concentrated sulfur foam, then continuously conveying the clear liquid to the one-effect separator for concentrating the desulfurization waste liquid, improving the total amount of the sulfur foam and the recovery rate of sulfur resources in the coke oven gas desulfurization waste liquid, then conveying the prepared sulfur foam to the incinerator for incineration to generate sulfur-containing flue gas, purifying, drying, converting and absorbing the sulfur-containing flue gas, and treating tail gas, so that the regeneration of the sulfur resources in the coke oven gas desulfurization waste liquid and the sulfur foam can be realized, fossil energy can be effectively saved, the emission of combustion waste gas is reduced, and the comprehensive economic benefit is remarkably improved.
Drawings
FIG. 1 is a schematic diagram of an overall structure of a production system for producing sulfuric acid from a desulfurization waste liquid of coke oven gas and sulfur foam according to an embodiment of the present invention;
the reference signs are: 11, a dilute sulfur foam tank, 111, a waste liquid input pipeline, 12, a microporous filter, 13, a clear liquid tank, 14, a concentrated sulfur foam tank, 141, a first conveying pipeline, 15, a first-effect separator, 16, a steam heater, 161, a forced circulation pump, 17, a steam output pipe, 171, a condenser, 18, a circulation discharge pipe, 19, a clear liquid return pipe, 20, an incinerator, 21, a waste heat boiler, 22, a secondary air preheater, 23, a primary air preheater, 31, a dynamic wave washing tower, 32, a packed washing tower, 33, an electric demister, 41, a drying tower, 42, an absorption tower, 51, a gas-gas heat exchanger, 52, a converter, 521, a catalytic packing layer, 61, a desulfurization tower, 62, a desorption tower, 63 and a gas-liquid separator.
Detailed Description
Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and therefore are only examples, and the protection scope of the present invention is not limited thereby.
As shown in fig. 1, the production system for preparing sulfuric acid from coke oven gas desulfurization waste liquid and sulfur foam provided in this embodiment includes a pretreatment section, an incineration section, a purification section, a conversion section, a dry absorption section, and a tail gas treatment section, where the pretreatment section is configured to collect and separate coke oven gas desulfurization waste liquid and sulfur foam in a centralized manner, and then incinerate the coke oven gas desulfurization waste liquid and sulfur foam in the incineration section, and the purification section, the conversion section, the dry absorption section, and the tail gas treatment section are configured to treat flue gas generated by incineration and absorb sulfur elements to prepare sulfuric acid.
In this embodiment, the pretreatment section includes a dilute sulfur foam tank 11 and a microporous filter 12 connected in sequence, the dilute sulfur foam tank 11 is provided with a waste liquid input pipeline 111, the upper part of the microporous filter 12 is connected with a clear liquid tank 13 through a clear liquid conveying pipe, the lower part of the microporous filter 12 is connected with a concentrated sulfur foam tank 14 through a concentrated sulfur conveying pipe, the concentrated sulfur foam tank 14 is connected with the incineration section through a first conveying pipe 141, and the incineration section is connected with the purification section through a second conveying pipe; the dry absorption section comprises a sulfuric acid drying tower 41 and a sulfuric acid absorption tower 42, the purification section is connected with the sulfuric acid drying tower 41 through a third conveying pipeline, the sulfuric acid drying tower 41 is connected with the conversion section through a fourth conveying pipeline, the conversion section is connected with the sulfuric acid absorption tower 42 through a fifth conveying pipeline, and the sulfuric acid absorption tower 42 is connected with the tail gas treatment section through a sixth conveying pipeline. In specific implementation, the dilute sulfur foam tank 11 can collect and buffer the coke oven gas desulfurization waste liquid and sulfur foam, then the dilute sulfur foam is pressurized by a dilute sulfur foam delivery pump and sent into the microporous filter 12 for filtration and separation, the solid-liquid separation is carried out on the coke oven gas desulfurization waste liquid and the sulfur foam through filter element micropores of the microporous filter 12, the filtrate at the upper part outlet of the microporous filter 12 is conveyed to the clear liquid tank 13 for buffer storage through a clear liquid conveying pipe, the content of the sulfur foam in the filtrate is below 5mg/m3, the concentrated slurry at the lower part of the microporous filter 12 is periodically discharged into the concentrated sulfur foam tank 14 through a concentrated sulfur conveying pipe for collection and buffer storage, and during implementation, the content of the sulfur foam in the concentrated slurry is controlled to be 50% ± 10%.
In this embodiment, the pretreatment section further includes an effective separator 15, the clear liquid tank 13 is communicated with the effective separator 15 through a liquid separation pipeline, the effective separator 15 is further connected with a steam heater 16 through a forced circulation pipeline, the forced circulation pipeline is provided with a forced circulation pump 161, the top end of the effective separator 15 is further provided with a steam output pipe 17, the tail end of the steam output pipe 17 is provided with a condenser 171, and the condenser 171 is used for condensing moisture in the steam to generate condensed water, and the condensed water can be sent back to the coke oven gas desulfurization system by a cooling water pump for recycling. Meanwhile, a discharge pipe is further arranged on the first-effect separator 15, the first-effect separator 15 is communicated with the concentrated sulfur foam tank 14 through the discharge pipe, and a circulating discharge pump is arranged on the discharge pipe. A clear liquid return pipe 19 is arranged on the clear liquid tank 13, and a clear liquid pump is arranged on the clear liquid return pipe 19. In specific implementation, the clear liquid pump sends most of clear liquid cached in the clear liquid tank 13 back to the coke oven gas desulfurization system to be recycled as desulfurization circulating absorption liquid, a small part of clear liquid (the clear liquid is called desulfurization waste liquid) is separated to carry out desulfurization waste liquid concentration, the desulfurization waste liquid is firstly sent into the one-effect separator 15, the desulfurization waste liquid automatically flows to the forced circulation pump 161, the desulfurization waste liquid is pressurized by the forced circulation pump 161 to enter the steam heater 16 for heating, the heated desulfurization waste liquid returns to the one-effect separator 15 for flash evaporation and concentration, the desulfurization waste liquid is circularly heated and flash evaporated, and secondary steam obtained by flash evaporation is condensed by the condenser 171. And after the salt content of the concentrated solution of the desulfurization waste liquid in the first-effect separator 15 reaches 50% + -10%, the concentrated solution is conveyed to a concentrated sulfur foam tank 14 through a circulating discharge pump, is mixed with concentrated sulfur foam filtered by a microporous filter 12, and is finally conveyed to an incinerator 20 of an incineration section through a concentrated sulfur foam pump for incineration.
In this embodiment, the incineration section includes an incinerator 20, the first conveying pipeline 141 is communicated with the incinerator 20, a waste heat boiler 21, a secondary air preheater 22 and a primary air preheater 23 are sequentially arranged at the downstream of the incinerator 20, and the primary air preheater 23 is communicated with the purification section through a second conveying pipeline. In specific implementation, the sulfur foam slurry pressurized and conveyed by a concentrated sulfur foam pump in the pretreatment section is atomized by compressed air in a spray gun and then is incinerated in an incinerator 20, and the desulfurized waste liquid and the sulfur foam are fully combusted at a high temperature of about 1150 ℃ to generate SO2 flue gas. The combustion air is heated and heated up step by the first-stage air preheater 23 and the second-stage air preheater 22, and then sent into the incinerator 20, and the main chemical reactions in the incinerator 20 are as follows:
S+O2＝SO2
NH4SCN+3O2＝N2+CO2+SO2+2H2O
2(NH4)2S2O3+5O2＝2N2+4SO2+8H2O
(NH4)2SO4+O2＝N2+SO2+4H2O
4NH3+3O2＝2N2+6H2O
the temperature of the flue gas at the outlet of the incinerator 20 is about 1150 ℃, the SO2 gas content is about 6%, the high-temperature flue gas firstly enters the waste heat boiler 21, the waste heat boiler 21 recovers the waste heat of the high-temperature flue gas, and the recovered heat generates medium-pressure saturated steam and is merged into a steam pipe network for use. The flue gas at the outlet of the waste heat boiler 21 exchanges heat with combustion air, is cooled to about 350 ℃ through the heat exchange of an air primary-secondary preheater, and finally the SO2 flue gas is sent to a purification section for evolution.
In the embodiment, the purification section comprises a dynamic wave washing tower 31, a packing washing tower 32 and an electric demister 33 which are connected in sequence, wherein the dynamic wave washing tower 31 is connected with the incinerator 20, and the electric demister 33 is connected to the dry absorption section. In the specific implementation, the incineration flue gas from the incineration working section enters the reverse spray pipe of the dynamic wave washing tower 31 from the upper part of the dynamic wave washing tower 31, then passes through the packing washing tower 32 for further temperature reduction and dust removal, finally the acid mist water mist is removed through the electric demister 33, and the purified flue gas is sent to the dry absorption working section continuously.
In this embodiment, the dry absorption section includes a drying tower 41 and an absorption tower 42, the drying tower 41 is connected to the purification section and the drying tower 41 is connected to the conversion section. In specific implementation, the purified flue gas is dried by concentrated sulfuric acid in a drying tower 41 and then is transported to a conversion section.
In this embodiment, the conversion section includes a heat exchange unit and a converter 52 disposed at the downstream of the heat exchange unit, a multi-section catalytic filler layer 521 is sequentially disposed in the converter 52 from top to bottom, and the catalytic filler layer 521 is filled with a catalytic filler for catalyzing sulfur dioxide to convert into sulfur trioxide. Specifically, the heat exchange unit includes a plurality of gas-gas heat exchangers 51 connected in series. In specific implementation, the flue gas from the dry absorption section and dried by the drying tower 41 passes through the plurality of gas-gas heat exchangers 51 in sequence to exchange heat and raise the temperature, and enters the converter 52 to be subjected to catalytic conversion.
In this embodiment, the converter 52 is connected to the absorber 42 of the dry suction section. In specific implementation, after the sulfur dioxide flue gas is converted into sulfur trioxide flue gas by the converter 52, the sulfur trioxide flue gas is sent back to the dry absorption working section again and enters the absorption tower 42, the sulfur trioxide flue gas enters the absorption tower 42 from the bottom of the absorption tower 42 and is absorbed by the concentrated sulfuric acid in the absorption tower 42, so that the sulfur trioxide is converted into sulfuric acid, thereby completing the recovery of sulfur resources in the coke oven gas desulfurization waste liquid and the sulfur foam, and the sulfur dioxide contained in the flue gas generated by the absorption working section continues to enter the tail gas treatment working section for treatment, thereby realizing the environmental-friendly standard emission of the flue gas.
In this embodiment, the tail gas treatment section includes a desulfurization tower 61, a desorption tower 62 and a gas-liquid separator 63 connected in sequence, the desulfurization tower 61 uses organic amine as a desulfurizing agent to remove sulfur dioxide, the organic amine becomes rich liquid after absorbing sulfur dioxide and is conveyed to the desorption tower 62 to be heated and desorbed, the flue gas generated in the desorption process is subjected to gas-liquid separation by the gas-liquid separator 63, the flue gas separated by the gas-liquid separator 63 is mixed with the flue gas generated in the purification section and is conveyed to the drying tower 41 to be subjected to cyclic treatment, so that sulfur resources are fully utilized, and the standard emission of the sulfur dioxide flue gas is facilitated.
Although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the utility model as defined in the appended claims. The techniques, shapes, and configurations not described in detail in the present invention are all known techniques.
Claims (5)
1. A production system for preparing sulfuric acid from coke oven gas desulfurization waste liquid and sulfur foam is characterized in that: the device comprises a pretreatment working section, a burning working section, a purification working section, a conversion working section, a dry absorption working section and a tail gas treatment working section, wherein the pretreatment working section comprises a dilute sulfur foam tank (11) and a microporous filter (12), a waste liquid input pipeline (111) is arranged on the dilute sulfur foam tank (11), the upper part of the microporous filter (12) is connected with a clear liquid tank (13) through a clear liquid conveying pipe, the lower part of the microporous filter (12) is connected with a concentrated sulfur foam tank (14) through a concentrated sulfur conveying pipe, the concentrated sulfur foam tank (14) is connected with the burning working section through a first conveying pipeline (141), and the burning working section is connected with the purification working section through a second conveying pipeline; the dry absorption working section comprises a sulfuric acid drying tower (41) and a sulfuric acid absorption tower (42), the purification working section is connected with the sulfuric acid drying tower (41) through a third conveying pipeline, the sulfuric acid drying tower (41) is connected with the conversion working section through a fourth conveying pipeline, the conversion working section is connected with the sulfuric acid absorption tower (42) through a fifth conveying pipeline, and the sulfuric acid absorption tower (42) is connected with the tail gas treatment working section through a sixth conveying pipeline.
2. The production system for preparing sulfuric acid from coke oven gas desulfurization waste liquid and sulfur foam as claimed in claim 1, characterized in that: the pretreatment working section further comprises an effect separator (15), the clear liquid tank (13) is communicated with the effect separator (15) through a liquid separating pipeline, the effect separator (15) is further connected with a steam heater (16) through a forced circulation pipeline, a forced circulation pump (161) is arranged on the forced circulation pipeline, a steam output pipe (17) is further arranged at the top end of the effect separator (15), and a condenser (171) is arranged at the tail end of the steam output pipe (17).
3. The production system for preparing sulfuric acid from coke oven gas desulfurization waste liquid and sulfur foam as claimed in claim 2, characterized in that: still be provided with the discharging pipe on one imitates separator (15) and pass through discharging pipe and dense sulphur foam groove (14) intercommunication, be provided with the circulation bleeder pump on the discharging pipe.
4. The production system for preparing sulfuric acid from coke oven gas desulfurization waste liquid and sulfur foam as claimed in claim 1, characterized in that: a clear liquid return pipe (19) is arranged on the clear liquid tank (13), and a clear liquid pump is arranged on the clear liquid return pipe (19).
5. The production system for preparing sulfuric acid from coke oven gas desulfurization waste liquid and sulfur foam as claimed in claim 1, characterized in that: the incineration section comprises an incinerator (20), a first conveying pipeline (141) is communicated with the incinerator (20), a waste heat boiler (21), a secondary air preheater (22) and a primary air preheater (23) are sequentially arranged at the lower reaches of the incinerator (20), and the primary air preheater (23) is communicated with the purification section through a second conveying pipeline.
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| CN202121263034.1U CN215403099U (en) | 2021-06-07 | 2021-06-07 | Production system for preparing sulfuric acid from coke oven gas desulfurization waste liquid and sulfur foam |
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| CN202121263034.1U CN215403099U (en) | 2021-06-07 | 2021-06-07 | Production system for preparing sulfuric acid from coke oven gas desulfurization waste liquid and sulfur foam |
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| CN202121263034.1U Active CN215403099U (en) | 2021-06-07 | 2021-06-07 | Production system for preparing sulfuric acid from coke oven gas desulfurization waste liquid and sulfur foam |
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