Method for cooperative treatment and recycling of sewage tail gas and sulfur dioxide
By combining cross-linked polymer-sulfonated macroporous resin and modified cation exchange resin, the problems of difficult wastewater and exhaust gas treatment and low resource utilization rate of pyrethroid insecticides have been solved, achieving efficient wastewater and exhaust gas treatment and resource recovery.
Patent Information
- Application Number
- CN202511559879.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-29
- Publication Date
- 2026-02-27
AI Technical Summary
Wastewater and exhaust gas from pyrethroid insecticides are difficult to treat, have high pesticide residue rates, high costs, and low recycling rates, making it difficult for existing technologies to effectively treat and utilize them as resources.
A cross-linked polymer-sulfonated macroporous resin composite filler is used to adsorb volatile organic compounds, sodium bisulfite solution is prepared using sulfur dioxide tail gas to remove cyanide, and heavy metal ions and residual organic matter are treated by modified cation exchange resin to achieve resource recycling.
It effectively removes volatile organic compounds and cyanides from wastewater, reduces harmful gas emissions, extends the life of packing materials, enables resource recovery and reuse, and reduces treatment costs.
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Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of sewage tail gas treatment, and particularly relates to a method for sewage tail gas and sulfur dioxide cooperative treatment and recycling. BACKGROUND
[0002] Pyrethroid insecticides are a class of high-efficiency, broad-spectrum, low-residue biomimetic pesticides, which are widely used in agriculture, forestry and horticulture. In the production process of pyrethroid insecticides, sewage tail gas containing cyanide, volatile organic compounds and acyl chloride tail gas is generated, which affects the ecological environment and human health. However, due to the characteristics of pyrethroid insecticide sewage tail gas, such as high content of refractory organic matter, poor biodegradability and low treatment efficiency, the current sewage tail gas treatment faces problems such as high treatment difficulty, high pesticide residue rate, high cost and low recycling rate. At the same time, with the increasingly stringent requirements of environmental protection, developing efficient, economical and environmentally friendly sewage tail gas treatment process has become a hot spot in pollution control.
[0003] Therefore, it is of great significance to develop a method for sewage tail gas and sulfur dioxide cooperative treatment and recycling. SUMMARY
[0004] The present application relates to the technical field of sewage tail gas treatment, and particularly relates to a method for sewage tail gas and sulfur dioxide cooperative treatment and recycling.
[0005] To achieve the above-mentioned purpose, the present application provides the following technical scheme: A method for sewage tail gas and sulfur dioxide cooperative treatment and recycling, comprising the following steps: S1: crosslinking polymer-sulfonated macroporous resin is loaded in a fixed bed adsorption column, and the filtered sewage is passed through the fixed bed adsorption column to obtain pretreated sewage; S2: sodium hydroxide is added to the pretreated sewage, the pH value is adjusted to 10-11, sodium bisulfite absorbing solution is added, air is introduced, stirring reaction is carried out, and then standing and precipitation, solid-liquid separation are carried out to obtain secondary treated sewage; S3: the modified resin is filled into the adsorption column, and the secondary treated sewage passes through the adsorption column to obtain dischargeable sewage.
[0006] Further, in step S1, the preparation method of the crosslinking polymer-sulfonated macroporous resin is as follows: sulfonated macroporous resin, crosslinking polymer and glutaraldehyde are placed in a dimethylformamide solution, sealed and stirred, filtered and dried, and then heat treated at 200-270 DEG C for 30-60 min under nitrogen protection to obtain the crosslinking polymer-sulfonated macroporous resin. In the preparation process of the crosslinking polymer-sulfonated macroporous resin, the mass ratio of sulfonated macroporous resin, crosslinking polymer and glutaraldehyde is 1:(0.03-0.05):(0.05-0.1).
[0007] Further, the preparation method of the sulfonated macroporous resin is as follows: add polystyrene macroporous resin to dichloromethane, stir and mix well, add concentrated sulfuric acid for sulfonation for 30-60 min, wash and dry to obtain sulfonated macroporous resin; In the preparation process of the sulfonated macroporous resin, the mass ratio of polystyrene macroporous resin to concentrated sulfuric acid is 1:(14-18).
[0008] Further, the preparation method of the cross-linked polymer is as follows: cashew phenol is added to 1,2 dichloroethane, stirred and mixed, ferric chloride is added, and under nitrogen protection, the mixture is heated to 35-40℃ and reacted for 16-24 hours. After washing, Soxhlet extraction and vacuum drying, the cross-linked polymer is obtained. In the preparation of the crosslinked polymer, the mass ratio of cashew phenol to ferric chloride is 1:(1-3).
[0009] Further, in step S2, the preparation method of the sodium bisulfite absorbent is as follows: collect acyl chloride tail gas, separate and collect sulfur dioxide tail gas through a separation device, spray sulfur dioxide with sodium bisulfite solution, collect the liquid, and obtain sodium bisulfite absorbent.
[0010] Further, in step S3, the modified resin is prepared as follows: sulfonyl chloride resin is added to propylene diamine, stirred and reacted at 60-80°C for 16-24 hours, washed and hydrolyzed to obtain the modified resin; In the preparation of the modified resin, the mass ratio of sulfonyl chloride resin to propylene diamine is 1:(10-15).
[0011] Further, the preparation method of the sulfonyl chloride resin is as follows: add dry hydrogen-form cation exchange resin to a container, add ethanol to swell, add pyridine, stir and react for 4-6 hours, then add chloroform and thionyl chloride, stir and react for 1-3 hours to obtain sulfonyl chloride resin; In the preparation process of the sulfonyl chloride resin, the mass ratio of hydrogen cation exchange resin, ethanol, pyridine, chloroform and thionyl chloride is 1:(1-3):(1-1.5):(1-3):(1-1.5).
[0012] Further, the preparation method of the hydrogen-form cation exchange resin is as follows: the sulfonic acid-type cation exchange resin is washed with deionized water, soaked in sodium hydroxide solution, washed with deionized water until neutral, stirred and exchanged with hydrochloric acid solution, washed until neutral, the above steps are repeated, and vacuum dried to obtain the hydrogen-form cation exchange resin.
[0013] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention introduces a cross-linked polymer-sulfonated macroporous resin composite packing to remove volatile organic compounds (VOCs) from wastewater. First, a cross-linked polymer is formed using cashew phenol as a raw material. Its high specific surface area and mesoporous structure not only facilitate the adsorption of VOCs from wastewater but also synergistically enhance the adsorption capacity and mechanical stability of the composite packing with the sulfonated macroporous resin. Second, the introduction of strong acidic cationic sulfonate groups onto the macroporous resin effectively adsorbs cationic pollutants from wastewater; simultaneously, the larger pore size improves the diffusion and adsorption efficiency of VOCs within the resin. Furthermore, glutaraldehyde is used as a cross-linking agent in the cross-linked polymer-sulfonated macroporous resin composite packing, strengthening the connection between the cross-linked polymer and the sulfonated macroporous resin, improving the mechanical stability of the packing, and extending its service life.
[0014] 2. This invention utilizes sulfur dioxide gas separated from acyl chloride tail gas to prepare sodium bisulfite absorbent, converting harmful sulfur dioxide tail gas into sodium bisulfite solution. This not only effectively reduces harmful gas emissions and prevents tail gas leakage, but also effectively removes cyanide from wastewater, achieving resource recycling.
[0015] 3. This invention introduces a modified cation exchange resin for the harmless treatment of secondary wastewater. Pyridine and thionyl chloride are grafted onto the cation exchange resin, introducing pyridine salt and sulfonyl chloride groups. This promotes the formation of sulfonamide bonds between the sulfonic acid groups and the amino groups on ethylenediamine, thereby introducing amino groups onto the cation exchange resin and improving its adsorption and separation of heavy metal ions and residual organic matter in the secondary wastewater. Simultaneously, the sulfur dioxide recovered from the acyl chloride gas generated in this process can be used to prepare sodium bisulfite solution to remove cyanide from the wastewater, achieving resource recycling. Detailed Implementation
[0016] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0017] In the following examples: the polystyrene macroporous resin is model AB-8; the sulfonic acid cation exchange resin is model D113; the CAS number of dichloromethane is 75-09-2; the CAS number of cashew phenol is 501-24-6; and the CAS number of thionyl chloride is 7719-09-7.
[0018] Example 1: A method for the co-treatment and reuse of wastewater exhaust gas and sulfur dioxide: Step 1: Wastewater pretreatment: S1: Add 1 part of polystyrene macroporous resin to dichloromethane, stir and mix well, add 14 parts of concentrated sulfuric acid and sulfonate for 30 min, wash and dry to obtain sulfonated macroporous resin. S2: Add 1 part cashew phenol to 1,2 dichloroethane, stir and mix well, add 1 part ferric chloride, heat to 35°C for 16 h under nitrogen protection, wash, Soxhlet extract, and vacuum dry at 80°C for 24 h to obtain crosslinked polymer. S3: Place 10 parts of sulfonated macroporous resin, 0.3 parts of crosslinking polymer, and 0.5 parts of glutaraldehyde in a dimethylformamide solution, seal and stir for 4 hours, filter and dry, and heat-treat at 200℃ for 30 minutes under nitrogen protection to obtain crosslinking polymer-sulfonated macroporous resin; S4: The cross-linked polymer-sulfonated macroporous resin is packed into a fixed bed adsorption column, and the wastewater filtered by the filter membrane is passed through the fixed bed adsorption column to obtain pretreated wastewater; Step Two: Secondary Wastewater Treatment S1: Collect acyl chloride tail gas, separate and collect sulfur dioxide tail gas through a separation device, spray sulfur dioxide with sodium sulfite solution, collect the liquid, and obtain sodium bisulfite absorbent. S2: Add sodium hydroxide to the pretreated wastewater, adjust the pH value to 11, add sodium bisulfite absorbent, introduce air, stir and react for 1 hour, let it stand to settle, separate solid and liquid, and obtain secondary treated wastewater. Step 3: Wastewater purification and discharge: S1: Wash the sulfonic acid type cation exchange resin with deionized water, soak it in sodium hydroxide solution for 4 hours, wash it with deionized water until neutral, stir and exchange it with hydrochloric acid solution for 2 hours, wash it until neutral, repeat the above steps, and vacuum dry it to obtain the hydrogen type cation exchange resin. S2: Add 1 part of dry hydrogen-form cation exchange resin to a container, add 1 part of ethanol to swell for 24 hours, add 1 part of pyridine, stir and react for 4 hours, then add 1 part of chloroform and 1 part of thionyl chloride, stir and react for 1 hour to obtain sulfonyl chloride resin. S3: Add 1 part of sulfonyl chloride resin to 10 parts of propylene diamine, stir at 60°C for 16 h, wash and hydrolyze to obtain the modified resin; S4: The modified resin is filled into the adsorption column, so that the secondary treated wastewater passes through the adsorption column to obtain wastewater that can be discharged.
[0019] Example 2: A method for the co-treatment and reuse of wastewater exhaust gas and sulfur dioxide: Step 1: Wastewater pretreatment: S1: Add 1 part of polystyrene macroporous resin to dichloromethane, stir and mix well, add 16 parts of concentrated sulfuric acid and sulfonate for 45 min, wash and dry to obtain sulfonated macroporous resin. S2: Add 1 part cashew phenol to 1,2 dichloroethane, stir and mix well, add 2 parts ferric chloride, heat to 38°C for 20 h under nitrogen protection, wash, Soxhlet extract, and vacuum dry at 80°C for 24 h to obtain crosslinked polymer. S3: Place 10 parts of sulfonated macroporous resin, 0.4 parts of crosslinking polymer, and 0.75 parts of glutaraldehyde in a dimethylformamide solution, seal and stir for 4 hours, filter and dry, and heat-treat at 240℃ for 45 minutes under nitrogen protection to obtain crosslinking polymer-sulfonated macroporous resin. S4: The cross-linked polymer-sulfonated macroporous resin is packed into a fixed bed adsorption column, and the wastewater filtered by the filter membrane is passed through the fixed bed adsorption column to obtain pretreated wastewater; Step Two: Secondary Wastewater Treatment S1: Collect acyl chloride tail gas, separate and collect sulfur dioxide tail gas through a separation device, spray sulfur dioxide with sodium sulfite solution, collect the liquid, and obtain sodium bisulfite absorbent. S2: Add sodium hydroxide to the pretreated wastewater, adjust the pH value to 11, add sodium bisulfite absorbent, introduce air, stir and react for 1 hour, let it stand to settle, separate solid and liquid, and obtain secondary treated wastewater. Step 3: Wastewater purification and discharge: S1: Wash the sulfonic acid type cation exchange resin with deionized water, soak it in sodium hydroxide solution for 4 hours, wash it with deionized water until neutral, stir and exchange it with hydrochloric acid solution for 2 hours, wash it until neutral, repeat the above steps, and vacuum dry it to obtain the hydrogen type cation exchange resin. S2: Add 1 part of dry hydrogen-form cation exchange resin to a container, add 1 part of ethanol to swell for 24 hours, add 1 part of pyridine, stir and react for 4 hours, then add 1 part of chloroform and 1 part of thionyl chloride, stir and react for 1 hour to obtain sulfonyl chloride resin. S3: Add 1 part of sulfonyl chloride resin to 10 parts of propylene diamine, stir at 60°C for 16 h, wash and hydrolyze to obtain the modified resin; S4: The modified resin is filled into the adsorption column, so that the secondary treated wastewater passes through the adsorption column to obtain wastewater that can be discharged.
[0020] Example 3: A method for the co-treatment and reuse of wastewater exhaust gas and sulfur dioxide: Step 1: Wastewater pretreatment: S1: Add 1 part of polystyrene macroporous resin to dichloromethane, stir and mix well, add 18 parts of concentrated sulfuric acid and sulfonate for 60 min, wash and dry to obtain sulfonated macroporous resin. S2: Add 1 part cashew phenol to 1,2 dichloroethane, stir and mix well, add 3 parts ferric chloride, heat to 40°C for 24 h under nitrogen protection, wash, Soxhlet extract, and vacuum dry at 80°C for 24 h to obtain crosslinked polymer. S3: Place 10 parts of sulfonated macroporous resin, 0.5 parts of crosslinking polymer, and 1 part of glutaraldehyde in a dimethylformamide solution, seal and stir for 4 hours, filter and dry, and heat-treat at 270℃ for 60 minutes under nitrogen protection to obtain crosslinking polymer-sulfonated macroporous resin. S4: The cross-linked polymer-sulfonated macroporous resin is packed into a fixed bed adsorption column, and the wastewater filtered by the filter membrane is passed through the fixed bed adsorption column to obtain pretreated wastewater; Step Two: Secondary Wastewater Treatment S1: Collect acyl chloride tail gas, separate and collect sulfur dioxide tail gas through a separation device, spray sulfur dioxide with sodium sulfite solution, collect the liquid, and obtain sodium bisulfite absorbent. S2: Add sodium hydroxide to the pretreated wastewater, adjust the pH value to 10, add sodium bisulfite absorbent, introduce air, stir and react for 1 hour, let it stand to settle, separate solid and liquid, and obtain secondary treated wastewater. Step 3: Wastewater purification and discharge: S1: Wash the sulfonic acid type cation exchange resin with deionized water, soak it in sodium hydroxide solution for 4 hours, wash it with deionized water until neutral, stir and exchange it with hydrochloric acid solution for 2 hours, wash it until neutral, repeat the above steps, and vacuum dry it to obtain the hydrogen type cation exchange resin. S2: Add 1 part of dry hydrogen-form cation exchange resin to a container, add 1 part of ethanol to swell for 24 hours, add 1 part of pyridine, stir and react for 4 hours, then add 1 part of chloroform and 1 part of thionyl chloride, stir and react for 1 hour to obtain sulfonyl chloride resin. S3: Add 1 part of sulfonyl chloride resin to 10 parts of propylene diamine, stir at 60°C for 16 h, wash and hydrolyze to obtain the modified resin; S4: The modified resin is filled into the adsorption column, so that the secondary treated wastewater passes through the adsorption column to obtain wastewater that can be discharged.
[0021] Example 4: A method for the co-treatment and reuse of wastewater exhaust gas and sulfur dioxide: Step 1: Wastewater pretreatment: S1: Add 1 part of polystyrene macroporous resin to dichloromethane, stir and mix well, add 18 parts of concentrated sulfuric acid and sulfonate for 60 min, wash and dry to obtain sulfonated macroporous resin. S2: Add 1 part cashew phenol to 1,2 dichloroethane, stir and mix well, add 3 parts ferric chloride, heat to 40°C for 24 h under nitrogen protection, wash, Soxhlet extract, and vacuum dry at 80°C for 24 h to obtain crosslinked polymer. S3: Place 10 parts of sulfonated macroporous resin, 0.5 parts of crosslinking polymer, and 1 part of glutaraldehyde in a dimethylformamide solution, seal and stir for 4 hours, filter and dry, and heat-treat at 270℃ for 60 minutes under nitrogen protection to obtain crosslinking polymer-sulfonated macroporous resin. S4: The cross-linked polymer-sulfonated macroporous resin is packed into a fixed bed adsorption column, and the wastewater filtered by the filter membrane is passed through the fixed bed adsorption column to obtain pretreated wastewater; Step Two: Secondary Wastewater Treatment S1: Collect acyl chloride tail gas, separate and collect sulfur dioxide tail gas through a separation device, spray sulfur dioxide with sodium sulfite solution, collect the liquid, and obtain sodium bisulfite absorbent. S2: Add sodium hydroxide to the pretreated wastewater, adjust the pH value to 10.5, add sodium bisulfite absorbent, introduce air, stir and react for 2 hours, let it stand to precipitate, separate solid and liquid, and obtain secondary treated wastewater; Step 3: Wastewater purification and discharge: S1: Wash the sulfonic acid type cation exchange resin with deionized water, soak it in sodium hydroxide solution for 4 hours, wash it with deionized water until neutral, stir and exchange it with hydrochloric acid solution for 2 hours, wash it until neutral, repeat the above steps, and vacuum dry it to obtain the hydrogen type cation exchange resin. S2: Add 1 part of dry hydrogen-form cation exchange resin to a container, add 1 part of ethanol to swell for 24 hours, add 1 part of pyridine, stir and react for 4 hours, then add 1 part of chloroform and 1 part of thionyl chloride, stir and react for 1 hour to obtain sulfonyl chloride resin. S3: Add 1 part of sulfonyl chloride resin to 10 parts of propylene diamine, stir at 60°C for 16 h, wash and hydrolyze to obtain the modified resin; S4: The modified resin is filled into the adsorption column, so that the secondary treated wastewater passes through the adsorption column to obtain wastewater that can be discharged.
[0022] Example 5: A method for the co-treatment and reuse of wastewater exhaust gas and sulfur dioxide: Step 1: Wastewater pretreatment: S1: Add 1 part of polystyrene macroporous resin to dichloromethane, stir and mix well, add 18 parts of concentrated sulfuric acid and sulfonate for 60 min, wash and dry to obtain sulfonated macroporous resin. S2: Add 1 part cashew phenol to 1,2 dichloroethane, stir and mix well, add 3 parts ferric chloride, heat to 40°C for 24 h under nitrogen protection, wash, Soxhlet extract, and vacuum dry at 80°C for 24 h to obtain crosslinked polymer. S3: Place 10 parts of sulfonated macroporous resin, 0.5 parts of crosslinking polymer, and 1 part of glutaraldehyde in a dimethylformamide solution, seal and stir for 4 hours, filter and dry, and heat-treat at 270℃ for 60 minutes under nitrogen protection to obtain crosslinking polymer-sulfonated macroporous resin. S4: The cross-linked polymer-sulfonated macroporous resin is packed into a fixed bed adsorption column, and the wastewater filtered by the filter membrane is passed through the fixed bed adsorption column to obtain pretreated wastewater; Step Two: Secondary Wastewater Treatment S1: Collect acyl chloride tail gas, separate and collect sulfur dioxide tail gas through a separation device, spray sulfur dioxide with sodium sulfite solution, collect the liquid, and obtain sodium bisulfite absorbent. S2: Add sodium hydroxide to the pretreated wastewater, adjust the pH value to 11, add sodium bisulfite absorbent, introduce air, stir and react for 3 hours, let it stand to settle, separate the solid and liquid, and obtain the secondary treated wastewater. Step 3: Wastewater purification and discharge: S1: Wash the sulfonic acid type cation exchange resin with deionized water, soak it in sodium hydroxide solution for 4 hours, wash it with deionized water until neutral, stir and exchange it with hydrochloric acid solution for 2 hours, wash it until neutral, repeat the above steps, and vacuum dry it to obtain the hydrogen type cation exchange resin. S2: Add 1 part of dry hydrogen-form cation exchange resin to a container, add 1 part of ethanol to swell for 24 hours, add 1 part of pyridine, stir and react for 4 hours, then add 1 part of chloroform and 1 part of thionyl chloride, stir and react for 1 hour to obtain sulfonyl chloride resin. S3: Add 1 part of sulfonyl chloride resin to 10 parts of propylene diamine, stir at 60°C for 16 h, wash and hydrolyze to obtain the modified resin; S4: The modified resin is filled into the adsorption column, so that the secondary treated wastewater passes through the adsorption column to obtain wastewater that can be discharged.
[0023] Example 6: A method for the co-treatment and reuse of wastewater exhaust gas and sulfur dioxide: Step 1: Wastewater pretreatment: S1: Add 1 part of polystyrene macroporous resin to dichloromethane, stir and mix well, add 18 parts of concentrated sulfuric acid and sulfonate for 60 min, wash and dry to obtain sulfonated macroporous resin. S2: Add 1 part cashew phenol to 1,2 dichloroethane, stir and mix well, add 3 parts ferric chloride, heat to 40°C for 24 h under nitrogen protection, wash, Soxhlet extract, and vacuum dry at 80°C for 24 h to obtain crosslinked polymer. S3: Place 10 parts of sulfonated macroporous resin, 0.5 parts of crosslinking polymer, and 1 part of glutaraldehyde in a dimethylformamide solution, seal and stir for 4 hours, filter and dry, and heat-treat at 270℃ for 60 minutes under nitrogen protection to obtain crosslinking polymer-sulfonated macroporous resin. S4: The cross-linked polymer-sulfonated macroporous resin is packed into a fixed bed adsorption column, and the wastewater filtered by the filter membrane is passed through the fixed bed adsorption column to obtain pretreated wastewater; Step Two: Secondary Wastewater Treatment S1: Collect acyl chloride tail gas, separate and collect sulfur dioxide tail gas through a separation device, spray sulfur dioxide with sodium sulfite solution, collect the liquid, and obtain sodium bisulfite absorbent. S2: Add sodium hydroxide to the pretreated wastewater, adjust the pH value to 11, add sodium bisulfite absorbent, introduce air, stir and react for 3 hours, let it stand to settle, separate the solid and liquid, and obtain the secondary treated wastewater. Step 3: Wastewater purification and discharge: S1: Wash the sulfonic acid type cation exchange resin with deionized water, soak it in sodium hydroxide solution for 4 hours, wash it with deionized water until neutral, stir and exchange it with hydrochloric acid solution for 2 hours, wash it until neutral, repeat the above steps, and vacuum dry it to obtain the hydrogen type cation exchange resin. S2: Add 1 part of dry hydrogen-form cation exchange resin to a container, add 2 parts of ethanol to swell for 24 hours, add 1.25 parts of pyridine, stir and react for 5 hours, then add 2 parts of chloroform and 1.25 parts of thionyl chloride, stir and react for 2 hours to obtain sulfonyl chloride resin. S3: Add 1 part of sulfonyl chloride resin to 13 parts of propylene diamine, stir at 70°C for 20 h, wash and hydrolyze to obtain the modified resin; S4: The modified resin is filled into the adsorption column, so that the secondary treated wastewater passes through the adsorption column to obtain wastewater that can be discharged.
[0024] Example 7: A method for the co-treatment and reuse of wastewater exhaust gas and sulfur dioxide: Step 1: Wastewater pretreatment: S1: Add 1 part of polystyrene macroporous resin to dichloromethane, stir and mix well, add 18 parts of concentrated sulfuric acid and sulfonate for 60 min, wash and dry to obtain sulfonated macroporous resin. S2: Add 1 part cashew phenol to 1,2 dichloroethane, stir and mix well, add 3 parts ferric chloride, heat to 40°C for 24 h under nitrogen protection, wash, Soxhlet extract, and vacuum dry at 80°C for 24 h to obtain crosslinked polymer. S3: Place 10 parts of sulfonated macroporous resin, 0.5 parts of crosslinking polymer, and 1 part of glutaraldehyde in a dimethylformamide solution, seal and stir for 4 hours, filter and dry, and heat-treat at 270℃ for 60 minutes under nitrogen protection to obtain crosslinking polymer-sulfonated macroporous resin. S4: The cross-linked polymer-sulfonated macroporous resin is packed into a fixed bed adsorption column, and the wastewater filtered by the filter membrane is passed through the fixed bed adsorption column to obtain pretreated wastewater; Step Two: Secondary Wastewater Treatment S1: Collect acyl chloride tail gas, separate and collect sulfur dioxide tail gas through a separation device, spray sulfur dioxide with sodium sulfite solution, collect the liquid, and obtain sodium bisulfite absorbent. S2: Add sodium hydroxide to the pretreated wastewater, adjust the pH value to 11, add sodium bisulfite absorbent, introduce air, stir and react for 3 hours, let it stand to settle, separate the solid and liquid, and obtain the secondary treated wastewater. Step 3: Wastewater purification and discharge: S1: Wash the sulfonic acid type cation exchange resin with deionized water, soak it in sodium hydroxide solution for 4 hours, wash it with deionized water until neutral, stir and exchange it with hydrochloric acid solution for 2 hours, wash it until neutral, repeat the above steps, and vacuum dry it to obtain the hydrogen type cation exchange resin. S2: Add 1 part of dry hydrogen-form cation exchange resin to a container, add 3 parts of ethanol to swell for 24 hours, add 1.5 parts of pyridine, stir and react for 6 hours, then add 3 parts of chloroform and 1.5 parts of thionyl chloride, stir and react for 3 hours to obtain sulfonyl chloride resin. S3: Add 1 part of sulfonyl chloride resin to 15 parts of propylene diamine, stir at 80°C for 24 hours, wash and hydrolyze to obtain the modified resin; S4: The modified resin is filled into the adsorption column, so that the secondary treated wastewater passes through the adsorption column to obtain wastewater that can be discharged.
[0025] Comparative Example 1: A method for the co-treatment and reuse of wastewater exhaust gas and sulfur dioxide: Step 1: Wastewater pretreatment: S1: Add 1 part of polystyrene macroporous resin to dichloromethane, stir and mix well, add 18 parts of concentrated sulfuric acid and sulfonate for 60 min, wash and dry to obtain sulfonated macroporous resin. S2: Sulfonated macroporous resin is packed into a fixed bed adsorption column, and the wastewater filtered by the filter membrane is passed through the fixed bed adsorption column to obtain pretreated wastewater; The remaining steps are the same as in Example 7.
[0026] Comparative Example 2: A method for the co-treatment and reuse of wastewater exhaust gas and sulfur dioxide: Step 2: Secondary treatment of wastewater: Sodium hydroxide was added to the pretreated wastewater to adjust the pH to 13. Sodium sulfite absorbent was added, air was introduced, the mixture was stirred and reacted for 3 hours, and the mixture was allowed to settle and precipitate. Solid-liquid separation was then performed to obtain the secondary treated wastewater. The remaining steps are the same as in Example 7.
[0027] Comparative Example 3: A method for the co-treatment and reuse of wastewater exhaust gas and sulfur dioxide: Step 3: Wastewater purification and discharge: S1: Wash the sulfonic acid type cation exchange resin with deionized water, soak it in sodium hydroxide solution for 4 hours, wash it with deionized water until neutral, stir and exchange it with hydrochloric acid solution for 2 hours, wash it until neutral, repeat the above steps, and vacuum dry it to obtain the hydrogen type cation exchange resin. S2: Fill the adsorption column with hydrogen-form cation exchange resin, so that the secondary treated wastewater passes through the adsorption column to obtain wastewater that can be discharged; The remaining steps are the same as in Example 7.
[0028] Testing: The wastewater prepared in the above examples and comparative examples was tested for cyanide in the wastewater according to the national standard HJ484-2009.
[0029] Table 1 Performance test data of dischargeable wastewater
[0030] Conclusion: This invention achieves the safe discharge and recycling of wastewater exhaust gas from pyrethroid insecticides by adjusting the processes at each stage of wastewater treatment.
[0031] In Comparative Example 1, only sulfonated macroporous resin was used as a packing material to remove organic matter from wastewater. Due to the lack of cross-linking polymer, not only was the organic matter adsorption capacity of the packing material reduced, but the mechanical strength and chemical stability of the packing material were also reduced, thereby reducing the service life of the packing material.
[0032] In Comparative Example 2, sodium sulfite was used to treat cyanide in wastewater, but the acyl chloride gas generated during the production of pyrethroid insecticides was not recovered, separated, or utilized, which increased the risk of environmental pollution.
[0033] In Comparative Example 3, only hydrogenated cation exchange resin was used to treat the wastewater to render it harmless. This reduced the resin's adsorption of residual organic matter and metal ions in the wastewater, increasing the risk of environmental pollution from the discharge of harmful compounds from the wastewater.
[0034] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.
Claims
1. A method for the co-treatment and reuse of wastewater exhaust gas and sulfur dioxide, characterized in that: Includes the following steps: S1: The cross-linked polymer-sulfonated macroporous resin is packed into a fixed bed adsorption column, and the wastewater filtered by the filter membrane is passed through the fixed bed adsorption column to obtain pretreated wastewater; S2: Add sodium hydroxide to the pretreated wastewater, adjust the pH value to 10-11, add sodium bisulfite absorbent, introduce air, stir the reaction, let it stand to precipitate, separate solid and liquid, and obtain secondary treated wastewater. S3: The modified resin is filled into the adsorption column, and the secondary treated wastewater is passed through the adsorption column to obtain wastewater that can be discharged.
2. The method for co-treatment and reuse of wastewater tail gas and sulfur dioxide according to claim 1, characterized in that: In step S1, the preparation method of the crosslinked polymer-sulfonated macroporous resin is as follows: sulfonated macroporous resin, crosslinked polymer, and glutaraldehyde are placed in a dimethylformamide solution, sealed and stirred, filtered and dried, and heat-treated at 200-270℃ for 30-60 min under nitrogen protection to obtain crosslinked polymer-sulfonated macroporous resin. In the preparation process of the crosslinked polymer-sulfonated macroporous resin, the mass ratio of sulfonated macroporous resin, crosslinked polymer, and glutaraldehyde is 1:(0.03-0.05):(0.05-0.1).
3. The method for co-treatment and reuse of wastewater tail gas and sulfur dioxide according to claim 2, characterized in that: The preparation method of the sulfonated macroporous resin is as follows: add polystyrene macroporous resin to dichloromethane, stir and mix well, add concentrated sulfuric acid for sulfonation for 30-60 min, wash and dry to obtain sulfonated macroporous resin. In the preparation process of the sulfonated macroporous resin, the mass ratio of polystyrene macroporous resin to concentrated sulfuric acid is 1:(14-18).
4. The method for co-treatment and reuse of wastewater tail gas and sulfur dioxide according to claim 2, characterized in that: The preparation method of the cross-linked polymer is as follows: cashew phenol is added to 1,2 dichloroethane, stirred and mixed, ferric chloride is added, and under nitrogen protection, the mixture is heated to 35-40℃ and reacted for 16-24 hours. The mixture is then washed, Soxhlet extracted, and vacuum dried to obtain the cross-linked polymer. In the preparation of the crosslinked polymer, the mass ratio of cashew phenol to ferric chloride is 1:(1-3).
5. The method for co-treatment and reuse of wastewater tail gas and sulfur dioxide according to claim 1, characterized in that: In step S2, the sodium bisulfite absorbent is prepared as follows: acyl chloride tail gas is collected, sulfur dioxide tail gas is separated and collected by a separation device, sulfur dioxide is sprayed with sodium bisulfite solution, and the liquid is collected to obtain sodium bisulfite absorbent.
6. The method for co-treatment and reuse of wastewater tail gas and sulfur dioxide according to claim 1, characterized in that: In step S3, the modified resin is prepared as follows: sulfonyl chloride resin is added to propylene diamine, stirred and reacted at 60-80℃ for 16-24h, washed and hydrolyzed to obtain the modified resin; In the preparation of the modified resin, the mass ratio of sulfonyl chloride resin to propylene diamine is 1:(10-15).
7. The method for co-treatment and reuse of wastewater tail gas and sulfur dioxide according to claim 6, characterized in that: The preparation method of the sulfonyl chloride resin is as follows: add dry hydrogen-form cation exchange resin to a container, add ethanol to swell, add pyridine, stir and react for 4-6 hours, then add chloroform and thionyl chloride, stir and react for 1-3 hours to obtain sulfonyl chloride resin. In the preparation process of the sulfonyl chloride resin, the mass ratio of hydrogen cation exchange resin, ethanol, pyridine, chloroform and thionyl chloride is 1:(1-3):(1-1.5):(1-3):(1-1.5).
8. The method for co-treatment and reuse of wastewater tail gas and sulfur dioxide according to claim 7, characterized in that: The preparation method of the hydrogen-form cation exchange resin is as follows: the sulfonic acid-type cation exchange resin is washed with deionized water, soaked in sodium hydroxide solution, washed with deionized water until neutral, stirred and exchanged with hydrochloric acid solution, washed until neutral, the above steps are repeated, and vacuum dried to obtain the hydrogen-form cation exchange resin.