CN112919678B - Acetic acid production wastewater treatment process - Google Patents
Acetic acid production wastewater treatment process Download PDFInfo
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- CN112919678B CN112919678B CN202110122699.9A CN202110122699A CN112919678B CN 112919678 B CN112919678 B CN 112919678B CN 202110122699 A CN202110122699 A CN 202110122699A CN 112919678 B CN112919678 B CN 112919678B
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F9/00—Multistage treatment of water, waste water or sewage
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B7/00—Halogens; Halogen acids
- C01B7/13—Iodine; Hydrogen iodide
- C01B7/14—Iodine
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/16—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation
- C07C51/285—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with peroxy-compounds
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/28—Treatment of water, waste water, or sewage by sorption
- C02F1/283—Treatment of water, waste water, or sewage by sorption using coal, charred products, or inorganic mixtures containing them
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
- C02F1/722—Oxidation by peroxides
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/34—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32
- C02F2103/36—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32 from the manufacture of organic compounds
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Abstract
The invention discloses a process for treating acetic acid production wastewater, which comprises the following steps: adding aqueous hydrogen peroxide into acetic acid production wastewater, and reacting hydrogen peroxide with iodide ions in the wastewater to generate an iodine simple substance; filtering solid iodine elementary substance generated by the reaction out of the wastewater, wherein the residual liquid is a liquid-phase product 1; adding activated carbon powder into the treated liquid-phase product 1; filtering the treated liquid-phase product 1, separating out the active carbon in the liquid-phase product, and taking the residual liquid as a liquid-phase product 2; adding aqueous hydrogen peroxide into the treated liquid-phase product 2, reacting the hydrogen peroxide with acetaldehyde in the liquid-phase product 2 to generate acetic acid, converting the liquid into a liquid-phase product 3, and conveying the liquid-phase product 3 to an acetic acid production system for separating the acetic acid. The acetic acid production wastewater treatment process can recycle iodine generated by iodine in wastewater, convert acetaldehyde in wastewater into acetic acid, improve acetic acid yield and avoid environmental pollution.
Description
Technical Field
The invention belongs to the technical field of industrial wastewater treatment and effective substance recycling, in particular to a treatment process of acetic acid production wastewater, and particularly relates to a low-cost treatment process of acetic acid production wastewater for recycling iodine and acetaldehyde in the acetic acid production wastewater.
Background
In the existing acetic acid production process, methanol carbonylation reaction is used as a main production process, and a large amount of hydroiodic acid is used in the production process. In the prior art, the methanol carbonylation reaction is not easy to completely react, homogeneous hydriodic acid and acetic acid products are not easy to separate, after a crude product is obtained, the crude product needs to be refined through a plurality of procedures such as primary separation, catalyst removal, promoter removal, acetaldehyde enrichment and the like to obtain a product acetic acid, waste water generated in the refining process is difficult to effectively recycle due to very high organic content and iodine content, and the organic matter in the waste water is further treated after iodine is absorbed by a silver-based material, so that the waste water can be discharged after reaching a discharge standard. The existing acetic acid production wastewater treatment process has the defects that the cost of the silver-based material adopted by the existing acetic acid production wastewater treatment process is very high, so that the wastewater treatment cost is greatly increased, and the method only discharges the wastewater after the wastewater treatment reaches the discharge standard, so that the acetaldehyde and the iodine in the wastewater cannot be effectively recycled, and the resource waste is caused, so that the existing acetic acid production wastewater treatment process needs to be improved.
Disclosure of Invention
The invention aims to provide a treatment process for acetic acid production wastewater, which can solve the problems that the treatment process for acetic acid production wastewater in the prior art is high in cost and acetaldehyde and iodine in the wastewater cannot be recycled.
In order to realize the purpose, the invention is realized by the following technical scheme: the acetic acid production wastewater treatment process is characterized in that: which comprises the following steps:
s1, adding aqueous hydrogen peroxide into acetic acid production wastewater, wherein the molar equivalent ratio of hydrogen peroxide to iodine in the wastewater is 1: 1-3;
s2, filtering the mixture after the reaction in the step S1, and separating solid iodine elementary substance generated by the reaction from the wastewater, wherein the residual liquid is a liquid-phase product 1;
s3, adding activated carbon powder into the liquid-phase product 1 treated in the step S2, wherein the mass ratio of the added activated carbon to the residual iodine in the liquid-phase product 1 is (1);
s4, filtering the liquid-phase product 1 treated in the step S3, separating out active carbon in the liquid-phase product, and taking the residual liquid as a liquid-phase product 2;
s5, adding aqueous hydrogen peroxide into the liquid-phase product 2 treated in the step S4, wherein the molar equivalent ratio of hydrogen peroxide to acetaldehyde in the wastewater is 1: 1-5, reacting the hydrogen peroxide with the acetaldehyde in the liquid-phase product 2 to generate acetic acid, converting the liquid into a liquid-phase product 3, and conveying the liquid-phase product 3 to an acetic acid production system for separating the acetic acid.
In the further scheme, in the step S1, the reaction is carried out under normal pressure, and the reaction temperature is 15-60 ℃. By controlling the reaction temperature, the rate of iodine simple substance generated by iodide ions in the wastewater is higher, the reaction efficiency is higher, and the best treatment effect is achieved.
In a further scheme, in the step S1, the reaction time is 5-60 min. By controlling the reaction time, the reaction of converting the iodide ions in the wastewater into the iodine simple substance is more sufficient, and the conversion rate is higher.
In the further scheme, in the step S5, the reaction is carried out under normal pressure, and the reaction temperature is 15-80 ℃. By controlling the reaction temperature, the ratio of acetaldehyde in the wastewater to generate acetic acid is higher, the reaction efficiency is higher, and the best treatment effect is achieved.
In a further scheme, in the step S5, the reaction time is 0.5-10h. By controlling the reaction time, the reaction of converting acetaldehyde in the wastewater into acetic acid is more sufficient, and the conversion rate is higher.
In the step S5, after the reaction of the hydrogen peroxide and the acetaldehyde is finished, the waste water is heated to 60-80 ℃ in a system with condensation reflux for 0.5-10h, so that the redundant hydrogen peroxide in the waste water is completely decomposed. After the hydrogen peroxide is decomposed, the acetic acid in the wastewater is separated, so that the purity of the obtained acetic acid is higher, the discharged wastewater does not contain hydrogen peroxide, and the acetic acid can be prevented from volatilizing by heating through a condensation reflux system.
In the further proposal, in the steps S2 and S4, the wastewater is filtered by adopting gravity filtration or reduced pressure filtration. Through gravity filtration or reduced pressure filtration, the iodine simple substance and the active carbon in the wastewater can be thoroughly separated, and the wastewater treatment efficiency is improved.
The further scheme is that after the treatment in the step S4, the iodine content in the liquid-phase product 2 is detected through starch, the iodine recovery rate in the liquid-phase product 2 reaches more than 99%, and the residual iodine content in the liquid-phase product 2 is less than 100 ppm.
In a further scheme, after the treatment in the step S5, the conversion rate of acetaldehyde in the liquid-phase product 2 into acetic acid is more than 85%.
It is further preferred that the concentration of the aqueous hydrogen peroxide solution in steps S1 and S5 is from 30 to 40% by weight.
The beneficial effects of the invention are as follows: 1) Compared with the prior art in which a silver-based material is adopted to treat iodide ions in wastewater, the treatment process of the acetic acid production wastewater and the wastewater treatment process greatly reduce the treatment cost; 2) The acetic acid production wastewater treatment process can separate iodine in the wastewater into iodine simple substances, recycle the waste and improve the economic benefit; 3) The acetic acid production wastewater treatment process can convert acetaldehyde in the wastewater into acetic acid, not only can improve the yield of the acetic acid and the economic benefit, but also can greatly reduce the content of the acetaldehyde in the wastewater, and the wastewater can be conveyed to an acetic acid production system to be reused for acetic acid production, thereby solving the problem of wastewater discharge and avoiding environmental pollution.
Drawings
FIG. 1 is a process flow diagram of the acetic acid production wastewater treatment process of the present invention.
FIG. 2 is a process flow diagram of the wastewater treatment process of example 1.
Detailed Description
The technical solutions of the present invention are described below clearly and completely by way of examples, and it is obvious that the described examples are only some examples of the present invention, and not all examples. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
A process for treating acetic acid production wastewater comprises the following steps:
s1, adding 30 wt% of hydrogen peroxide aqueous solution into acetic acid production wastewater, wherein the molar equivalent ratio of hydrogen peroxide to iodine in the wastewater is 1:1, reacting the hydrogen peroxide with iodine ions in the wastewater to generate iodine simple substance, and reacting at the normal pressure at the reaction temperature of 15 ℃ for 60min;
s2, filtering the mixture after the reaction in the step S1, and separating solid iodine elementary substance generated by the reaction from the wastewater, wherein the residual liquid is a liquid-phase product 1;
s3, adding activated carbon powder into the liquid-phase product 1 treated in the step S2, wherein the mass ratio of the added activated carbon to the residual iodine in the liquid-phase product 1 is 1;
s4, filtering the liquid-phase product 1 treated in the step S3, separating out active carbon in the liquid-phase product, and taking the residual liquid as a liquid-phase product 2;
s5, adding 30 wt% of hydrogen peroxide aqueous solution into the liquid-phase product 2 treated in the step S4, wherein the molar equivalent ratio of hydrogen peroxide to acetaldehyde in the wastewater is 1:1, the hydrogen peroxide reacts with the acetaldehyde in the liquid-phase product 2 under normal pressure, the reaction temperature is 15 ℃, the reaction time is 10 hours, acetic acid is generated, the liquid is converted into the liquid-phase product 3, the liquid-phase product 3 is heated to 60 ℃ in a heating system with condensation reflux and lasts for 10 hours, so that the redundant hydrogen peroxide in the wastewater is completely decomposed, then the liquid-phase product 3 is conveyed into an acetic acid production system, and the acetic acid in the liquid-phase product 3 is separated through the acetic acid production system.
Example 2
A process for treating acetic acid production wastewater comprises the following steps:
s1, adding 30 wt% of aqueous hydrogen peroxide into acetic acid production wastewater, wherein the molar equivalent ratio of hydrogen peroxide to iodine in the wastewater is 2: 1, reacting the hydrogen peroxide with iodine ions in the wastewater to generate an iodine simple substance, and reacting at the normal pressure for 20min at the reaction temperature of 30 ℃;
s2, performing gravity filtration or reduced pressure filtration on the mixture after the reaction in the step S1, separating solid iodine elementary substance generated by the reaction from the wastewater, and taking the residual liquid as a liquid-phase product 1;
s3, adding activated carbon powder into the liquid-phase product 1 treated in the step S2, wherein the mass ratio of the added activated carbon to the residual iodine in the liquid-phase product 1 is 1;
s4, performing gravity filtration or reduced pressure filtration on the liquid-phase product 1 treated in the step S3 to separate out active carbon, wherein the residual liquid is the liquid-phase product 2;
s5, adding 40 wt% of aqueous hydrogen peroxide into the liquid-phase product 2 treated in the step S4, enabling the molar equivalent ratio of hydrogen peroxide to acetaldehyde in the wastewater to be 1: 3, enabling the hydrogen peroxide to react with the acetaldehyde in the liquid-phase product 2 at normal pressure, enabling the reaction temperature to be 30 ℃ and the reaction time to be 5 hours, generating acetic acid, converting the liquid into the liquid-phase product 3, heating the liquid-phase product 3 to 80 ℃ in a heating system with condensation reflux and continuing for 0.5 hour to completely decompose redundant hydrogen peroxide in the wastewater, then conveying the liquid-phase product 3 into an acetic acid production system, and separating the acetic acid in the liquid-phase product 3 through the acetic acid production system.
Example 3
A process for treating acetic acid production wastewater comprises the following steps:
s1, adding 40 wt% of aqueous hydrogen peroxide into acetic acid production wastewater, wherein the molar equivalent ratio of hydrogen peroxide to iodine in the wastewater is 3:1, reacting the hydrogen peroxide with iodine ions in the wastewater to generate an iodine simple substance, and reacting at the normal pressure at the reaction temperature of 60 ℃ for 5min;
s2, filtering the mixture after the reaction in the step S1, and separating solid iodine elementary substance generated by the reaction from the wastewater, wherein the residual liquid is a liquid-phase product 1;
s3, adding activated carbon powder into the liquid-phase product 1 treated in the step S2, wherein the mass ratio of the added activated carbon to the residual iodine in the liquid-phase product 1 is 1;
s4, filtering the liquid-phase product 1 treated in the step S3, separating out active carbon in the liquid-phase product, and taking the residual liquid as a liquid-phase product 2;
s5, adding 30 wt% of hydrogen peroxide aqueous solution into the liquid-phase product 2 treated in the step S4, wherein the molar equivalent ratio of hydrogen peroxide to acetaldehyde in the wastewater is 1:5, reacting the hydrogen peroxide with the acetaldehyde in the liquid-phase product 2 at normal pressure, wherein the reaction temperature is 80 ℃, the reaction time is 0.5h, generating acetic acid, converting the liquid into the liquid-phase product 3, conveying the liquid-phase product 3 into an acetic acid production system, and separating the acetic acid in the liquid-phase product 3 through the acetic acid production system.
As shown in fig. 2, through experiments, in step 4 of examples 1 to 3 of the present invention, activated carbon powder can not only filter iodine in the liquid-phase product 1, but also perform adsorption and decoloration on the liquid-phase product 1, so that the liquid-phase product 2 obtained after the treatment becomes a clarified liquid, and the iodine content in the liquid-phase product 2 is detected by using starch, and the experimental results show that the iodine recovery rate in the liquid-phase product 2 can reach more than 99%, and the residual iodine content in the liquid-phase product 2 reaches less than 100 ppm. And (3) detecting the liquid-phase product 3 treated in the step (S5), wherein experimental results show that the conversion rate of acetaldehyde into acetic acid can reach more than 85%.
The following table is a calculation table of the income of each ton of acetic acid production wastewater treated by the acetic acid production wastewater treatment process of the invention:
as can be seen from the above table, by using the acetic acid wastewater treatment process of the invention, 396.22 yuan can be obtained for each ton of acetic acid wastewater, and if 10 ten thousand tons of wastewater rich in iodine and acetaldehyde are treated for an acetic acid manufacturing plant every year, 3962.2 ten thousand yuan can be obtained.
Through the embodiments, it can be seen that, the acetic acid wastewater treatment process of the invention can greatly reduce the wastewater treatment cost, recycle iodine and acetaldehyde in the wastewater, generate a large amount of economic benefits, and simultaneously, remove acetaldehyde in the wastewater, ensure that the discharged wastewater is more environment-friendly and safer, and avoid environmental pollution.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (8)
1. A process for treating acetic acid production wastewater is characterized by comprising the following steps:
s1, adding aqueous hydrogen peroxide into acetic acid production wastewater, wherein the molar equivalent ratio of hydrogen peroxide to iodine in the wastewater is 1: 1-3;
s2, filtering the mixture after the reaction in the step S1, and separating solid iodine elementary substance generated by the reaction from the wastewater, wherein the residual liquid is a liquid-phase product 1;
s3, adding activated carbon powder into the liquid-phase product 1 treated in the step S2, wherein the mass ratio of the added activated carbon to the residual iodine in the liquid-phase product 1 is 1;
s4, filtering the liquid-phase product 1 treated in the step S3, separating out active carbon in the liquid-phase product, and taking the residual liquid as a liquid-phase product 2;
s5, adding aqueous hydrogen peroxide into the liquid-phase product 2 treated in the step S4, wherein the molar equivalent ratio of hydrogen peroxide to acetaldehyde in the wastewater is 1: 1-5;
in the step S1, reaction is carried out under normal pressure, and the reaction temperature is 15-60 ℃;
in step S1, the reaction time is 5-60 min.
2. The acetic acid production wastewater treatment process according to claim 1, characterized in that: in step S5, the reaction is carried out under normal pressure, and the reaction temperature is 15-80 ℃.
3. The acetic acid production wastewater treatment process according to claim 1, characterized in that: in step S5, the reaction time is 0.5-10h.
4. The acetic acid production wastewater treatment process according to claim 1, characterized in that: in step S5, after the reaction of the hydrogen peroxide and the acetaldehyde is finished, the wastewater is heated to 60-80 ℃ in a system with condensation reflux for 0.5-10h, so that the redundant hydrogen peroxide in the wastewater is completely decomposed.
5. The acetic acid production wastewater treatment process according to claim 1, characterized in that: and in the steps S2 and S4, filtering the wastewater by adopting gravity filtration or reduced pressure filtration.
6. The acetic acid production wastewater treatment process according to claim 1, characterized in that: and after the treatment in the step S4, detecting the iodine content in the liquid-phase product 2 through starch, wherein the iodine recovery rate in the liquid-phase product 2 is more than 99%, and the residual iodine content in the liquid-phase product 2 is less than 100 ppm.
7. The acetic acid production wastewater treatment process according to claim 1, characterized in that: after the treatment of the step S5, the conversion rate of the acetaldehyde in the liquid-phase product 2 into the acetic acid is more than 85%.
8. The acetic acid production wastewater treatment process according to claim 1, characterized in that: in steps S1 and S5, the concentration of the aqueous hydrogen peroxide solution is 30 to 40 wt%.
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| CN113636687A (en) * | 2021-09-14 | 2021-11-12 | 江苏集萃托普索清洁能源研发有限公司 | Resource utilization process for high-value chemicals in acetic acid plant wastewater |
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| JPH0920698A (en) * | 1995-07-05 | 1997-01-21 | Kobe Steel Ltd | Production of organic compound showing affinity to hydrophilic medium |
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| US5175362A (en) * | 1991-05-29 | 1992-12-29 | Eastman Kodak Company | Recovery of acetyl values from ethylidene diacetate |
| DE4236724A1 (en) * | 1992-10-30 | 1994-05-05 | Schering Ag | Process for the recovery of iodine from iodinated organic compounds |
| CN1221511C (en) * | 2003-09-05 | 2005-10-05 | 上海吴泾化工有限公司 | Acetic acid purification process |
| CN1312101C (en) * | 2004-10-15 | 2007-04-25 | 上海吴泾化工有限公司 | Acetic acid refining method for improving acetic acid potassium permanganate test time |
| CN105948305A (en) * | 2016-05-12 | 2016-09-21 | 同济大学 | Method for reducing generation of I-DBPs (iodinated disinfection by-products) through chemical pre-oxidation |
| CN110194501A (en) * | 2019-04-30 | 2019-09-03 | 凯莱英医药化学（阜新）技术有限公司 | From the continuous process and continuous device for recycling iodide in waste water containing iodine |
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