CN1927745A - Process for treating waste water of refined terephthalic acid - Google Patents
Process for treating waste water of refined terephthalic acid Download PDFInfo
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- CN1927745A CN1927745A CN 200610041561 CN200610041561A CN1927745A CN 1927745 A CN1927745 A CN 1927745A CN 200610041561 CN200610041561 CN 200610041561 CN 200610041561 A CN200610041561 A CN 200610041561A CN 1927745 A CN1927745 A CN 1927745A
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- waste water
- terephthalic acid
- treatment process
- factory effluent
- pure terephthalic
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Abstract
The process of treating waste water from refined terephthalic acid production belongs to the field of environment protecting engineering and industrial effluent treating technology. The process includes settling and filtering of the waste water, oxidizing degradation in an oxidizing tower with composite catalyst, blowing aeration treatment and the next biochemical treatment. The water solution of ClO2 as the main oxidant has concentration of 0.03 %-5 % and the thrown amount of 5 %-20 % of waste water COD concentration; and the auxiliary oxidant of O2, air and/or H2O2 has the volume ratio to the waste water of 100-110 to 1. The process of the present invention has the features of small covered area, low running cost, low chemical consumption, high treating efficiency, no waste water exhaust, closed water circulation, etc.
Description
Technical field
The invention belongs to environmental engineering and technology for treating industrial waste water field, relate in particular to a kind of treatment process of pure terephthalic acid's factory effluent.
Background technology
PTA (pure terephthalic acid) is the important source material of producing products such as synthetic resins, polyster fibre, and present domestic PTA device all adopts p xylene oxidation technology, has produced a large amount of high concentrated organic wastewaters in the production process, the waste water composition complexity.Principal pollutant comprise toluene, p-Xylol, p-methylbenzoic acid, terephthalaldehydic acid, terephthalic acid (PTA or TA), phthalic acid, phenylformic acid, to tens kinds of organic pollution materials such as carboxyl benzaldehyde, cobalt-manganese catalysts, water quality is complicated and changeable, has increased the difficulty of administering greatly.But owing to be subjected to the influence of the market requirement, PTA production equipment scale constantly promotes, thereby the comprehensive regulation work of PTA factory effluent is also urgent day by day.
The water quality of PTA waste water is relevant with its concrete production technology, mainly the technological line with Britain ICI chemical company and U.S. Amoco chemical company is representative, the PTA waste water COD of ICI company technological line is lower, and generally at 4000～6000mg/L, wherein TA is 1000mg/L; The PTA waste water COD of Amoco company technological line is higher, and generally at 6000～9000mg/L, wherein TA is 2000～3000mg/L.To the processing of PTA waste water, more in the world at present employing aerobe is handled, and extended aeration process (U.S.) and flocculation-activation process (Japan) are specifically arranged; The former grows (about 15 days) residence time, and floor space is bigger; The latter needs with the river dilution, and flow process is longer, and the waste water COD after the processing is reduced to 800mg/L from 5000mg/L, reaches direct emission standards far away.What domestic how tame sewage work adopted is physics method and biological process bonded combination process, through pre-treatment, A/O method handle, biochemical degradation, make the COD value of waste water reach corresponding emission standard at last and discharge.The deficiency that this treatment process exists is: the residence time is long, the plant area area is big, turndown ratio is little, processing efficiency is low, comprehensive cost is high, and the fluctuation because of source water quality sometimes may cause exceeding standard of final outlet water quality.
Advanced oxidation processes (Advanced Oxidation Process, be called for short AOPs) be the processing toxic pollutant technology that begins to form the eighties in 20th century, its feature is to produce hydroxyl radical free radical (OH) by reaction, this free radical has extremely strong oxidisability, organic pollutant effectively can be decomposed by free radical reaction, even be converted into harmless inorganics up hill and dale, as carbonic acid gas and water etc.Because advanced oxidation processes has the advantage that oxidisability is strong, operational condition is easy to control, therefore cause the attention of countries in the world, and carried out the research-and-development activity of this direction in succession.
Prior art has proposed some kinds of methods the PTA production wastewater treatment has been improved.As: Chinese patent CN1033176A proposition is a kind of handles method of terephthalic acid in the trade effluent with molysite, mainly adopts ferric sulfate or iron trichloride that the terephthaldehyde's acid deposition in the waste water is handled, and is removed by filtering then.Regulate pH to 4～4.5, add an amount of polyacrylamide simultaneously to improve the precipitation threshold of terephthalic acid, the clearance of terephthalic acid can reach more than 90%.
Patents such as CN1039784A, CN1176228A, CN94118737.3 all in various degree the metabolism that utilizes microorganism of mentioning are removed organic pollutant in the waste water, i.e. traditional activated sludge process, two sections aerobic activated sludge process and anaerobic-aerobic segmentation activated sludge process.These methods can effectively be handled organic wastewater to a certain extent, but have also that floor space is big, startup and difficult in maintenance, shortcoming such as total hrt is long, energy consumption is high and surplus sludge volume is big, limited its applying in the PTA wastewater treatment.
The biotechnology that patent CN02138171.2, CN02151512.3 mention the special efficacy microbiobacterial agent combines with genetically engineered, the protoplasma of different parental plant thalline is merged, by gene reconfiguring in same cell, make up the genetic engineering bacterium and the preparation antibacterial polyester that obtain and reach degrading high concentration organic waste water.This method also exists employed thalline to be difficult to cultivate and breeding, and the not high defective of bacterial classification surviving rate also is not the method for sophisticated treatment PTA waste water at present.
PTA waste water after patent report will filter in addition is by being equipped with the adsorption column of macroporous adsorbent resin, wherein terephthalic acid and benzene series organism such as intermediate thereof are adsorbed on the resin, resin carries out wash-out regeneration with aqueous sodium hydroxide solution behind adsorption operations, the high density benzene series organism that desorption is got off carries out acidifying, cold filtration, filtrate return the raw wastewater circular treatment.This technology has realized effectively separating of benzene series organism and waste water to a certain extent, but resin is through wash-out regeneration repeatedly simultaneously, and its adsorption efficiency also reduces greatly, has influenced its treatment capacity, and is unfavorable to the bigger device operation.
Summary of the invention
The present invention is on the basis of conventional process route innovative research, dioxide peroxide advanced oxidation processes and catalysis technique are coupled, to filtering terephthalic acid wastewater after the sedimentation by the oxidizing tower of composite catalyst is housed, with the degraded of benzene series oxidation operations such as wherein PTA waste water and intermediate thereof, its COD is reduced to below the 420mg/L, terephthalic acid and phenylformic acid are reduced to below the 5ppm, handle after the PTA waste water that aeration is handled can directly enter the next stage biochemical system.Adopt method of the present invention, not only can reduce floor space, reduce working cost, save medicament, can realize also that the residence time is short, processing efficiency is high and the PTA cleaner production of non-wastewater discharge, water closed cycle.
Preparation method of the present invention is as follows:
It comprises processes such as sedimentation filtration, chemical oxidation, and the PTA waste water after sedimentation, filtration drops in the container, and in proportion to wherein dropping into oxygenant ClO
2Deng, mix then, with carrying out oxidative degradation in the waste water suction fixed bed catalytic reactor for preparing, by blower fan to reaction tower in blast air in the reaction process by volume pump, handle after directly enter the next stage biochemical system behind the wastewater to reach standard that aeration is handled.Primary oxidant ClO wherein
2The concentration of the aqueous solution is 0.03%～5%, preferred concentration is 0.07%～0.15% (700mg/L～1500mg/L), ClO
2Dosage in waste water is 5%～20% of a waste water COD concentration, and preferable range is 7%～10%; Secondary oxidizer can adopt O
2, air, H
2O
2Or wherein several, the volume ratio of secondary oxidizer and waste water is controlled at 100～110: 1.
Settling process adopts continuous settling methods to separate contained TA solid granules such as (terephthalic acids) in the waste water, and the residence time, preferable range was 20～30 hours at 10～60 hours.
Filtration procedure adopts suction method or filter press technique to remove contained solid particulate in the waste water, and the COD place to go rate of waste water fluctuates with the change of water quality of source waste water in the process, between 25%～65%.
Employed oxide catalyst is the metal-salt mixture that loads on the activated carbon granule.Its oxidation catalyst activity components system is one or more among the Lewis hydrochlorate AXBY, wherein A=Al
3+, Zn
2+, Fe
3+, Sn
2+, Co
3+, Cu
2+, Sb
3+, Ti
3+, Mn
4+, Pb
2+, Mg
2+, Ni
3+, B=Cl, Br, F, SO
4 2, CH
3COO, NO
3 -The carrier of described oxide catalyst is a gac, and wherein carrier active carbon fills in fixed-bed reactor with the form of filling, and the filling voidage is 10～20%.Wherein supported catalyst dipping concentration is 2～16%, and wherein most preferred range 5～6%.
Through containing a small amount of active oxygen oxygenant material in the waste water behind the catalyzed oxidation, its existence meeting has a negative impact to follow-up biological process, can increase aeration and handle, in the time of with the further oxidative degradation waste water of air, decompose and destroy a small amount of reactive oxygen species that wherein may contain.
Advantage of the present invention is mainly reflected in following several respects:
1. the present invention adopts dioxide peroxide advanced oxidation processes and catalysis technique to be coupled, and has realized the oxidative degradation of PTA high concentrated organic wastewater, reaches good treatment effect.
2. the specific catalyst system of this process using, its supported catalyst adopts gac to make carrier, under Lewis acid salt solution dipping, form through sintering, be seated in after surface treatment in the oxidizing tower, it has the following advantages: the catalytic efficiency height, it is catalyzer, be again sorbent material, the PTA waste water system no suspended substance after the processing, water cleaning.
3. this technology is treatment PTA waste water under the normal temperature condition, and condition is gentle relatively, and turndown ratio is big, and oxidative degradation is deep, and working cost is low.
The present invention compared with prior art has the reaction conditions gentleness, the catalyst activity height, catalytic performance is good, can handle the organic composite waste of chemical industry of any concentration, process " cleaning " and advantage such as easy to operate are a kind of eco-friendly friendly process of treatment PTA waste water.
Embodiment
The following examples will be further specified the present invention, but not thereby limiting the invention.
Embodiment 1
The PTA waste water of weighing 1000ml through 30 hours gravity settlings, after filtering drops in the container, and to wherein dropping into 5% oxygenant ClO
2The aqueous solution, concentration is 0.03%, mix then, by volume pump the waste water suction for preparing is filled with in the fixed bed catalytic reactor of 2% concentration cobalt nitrate solution supported active Pd/carbon catalyst and carries out oxidative degradation, oxidizing tower filling voidage is 10～20%, in reaction tower, blast air by blower fan in the reaction process, the volume ratio of air and waste water is 105～110: 1, the pH value of solution is 4.5, temperature of reaction is a room temperature, keeping the residence time of waste water in tower is 60min, waste water COD after the processing is reduced to 420mg/L, terephthalic acid and phenylformic acid are reduced to 5ppm, after aeration is handled and directly to be entered the next stage biochemical system after up to standard and handle.
Embodiment 2
In the identical device of embodiment 1, the PTA waste water of weighing 1500ml through sedimentation, after filtering drops in the container, and to wherein dropping into 20% oxygenant ClO
2The aqueous solution, concentration is 5%, mix then, by volume pump the waste water suction for preparing is filled with in the fixed bed catalytic reactor of 5% concentration cobalt nitrate solution supported active Pd/carbon catalyst and carries out oxidative degradation, oxidizing tower filling voidage is 10～20%, in reaction tower, blast oxygen by blower fan in the reaction process, the volume ratio of oxygen and waste water is 105～110: 1, the pH value of solution is 4.5, temperature of reaction is a room temperature, and keeping the residence time of waste water in tower is 60min, and the waste water COD after the processing is reduced to 408mg/L, terephthalic acid and phenylformic acid are reduced to 5ppm, after aeration is handled and directly to be entered the next stage biochemical system after up to standard and handle.
Embodiment 3
In the identical device of embodiment 1, the PTA waste water of weighing 1000ml through sedimentation, after filtering drops in the container, and to wherein dropping into 10% oxygenant ClO
2The aqueous solution, concentration is 1%, mix then, by volume pump the waste water suction for preparing is filled with in the fixed bed catalytic reactor of 8% concentration iron nitrate solution supported active Pd/carbon catalyst and carries out oxidative degradation, oxidizing tower filling voidage is 10～20%, in reaction tower, blast air by blower fan in the reaction process, the volume ratio of air and waste water is 105～110: 1, the pH value of solution is 4.5, temperature of reaction is a room temperature, and keeping the residence time of waste water in tower is 90min, and the waste water COD after the processing is reduced to 400mg/L, terephthalic acid and phenylformic acid are reduced to 4.5ppm, after aeration is handled and directly to be entered the next stage biochemical system after up to standard and handle.
Embodiment 4
In the identical device of embodiment 1, the PTA waste water of weighing 1500ml through sedimentation, after filtering drops in the container, and to wherein dropping into 15% oxygenant ClO
2The aqueous solution, concentration is 2%, mix then, by volume pump the waste water suction for preparing is filled with in the fixed bed catalytic reactor of 12% concentration cobalt acetate solution supported active Pd/carbon catalyst and carries out oxidative degradation, oxidizing tower filling voidage is 10～20%, in reaction tower, blast oxygen by blower fan in the reaction process, the volume ratio of oxygen and waste water is 105～110: 1, the pH value of solution is 4.5, temperature of reaction is a room temperature, keeping the residence time of waste water in tower is 90min, waste water COD after the processing is reduced to 395mg/L, terephthalic acid and phenylformic acid are reduced to 4.3ppm, after aeration is handled and directly to be entered the next stage biochemical system after up to standard and handle.
Embodiment 5
In the identical device of embodiment 1, the PTA waste water of weighing 3000ml through sedimentation, after filtering drops in the container, and to wherein dropping into 18% oxygenant ClO
2The aqueous solution, concentration is 3%, mix then, by volume pump the waste water suction for preparing is filled with in the fixed bed catalytic reactor of 16% concentration liquor zinci chloridi supported active Pd/carbon catalyst and carries out oxidative degradation, oxidizing tower filling voidage is 10～20%, in reaction tower, blast hydrogen peroxide by blower fan in the reaction process, the volume ratio of hydrogen peroxide and waste water is 105～110: 1, the pH value of solution is 4.5, temperature of reaction is a room temperature, keeping the residence time of waste water in tower is 90min, waste water COD after the processing is reduced to 402mg/L, terephthalic acid and phenylformic acid are reduced to 4.2ppm, after aeration is handled and directly to be entered the next stage biochemical system after up to standard and handle.
This invention is by effectively regulating the influence to COD value, chroma removal rate of pH value, reaction times and oxygenant dosage, optimized the operational condition of wastewater treatment, final with lower cost with operate easily the COD value of PTA combined sewage is reduced to about 420mg/L, this waste water can enter the biological degradation system and handle its COD value is reduced to below the 100mg/L.Utilization composite catalytic oxidation method treatment PTA waste water has been filled up the application blank of advanced oxidation processes in PTA wastewater treatment research field, has the incomparable series of advantages of bioremediation.
Claims (10)
1. the treatment process of pure terephthalic acid's factory effluent is characterized in that it comprises processes such as sedimentation filtration, chemical oxidation, and the PTA waste water after sedimentation, filtration drops in the container, and in proportion to wherein dropping into primary oxidant ClO
2And secondary oxidizer, mix then, to carry out oxidative degradation in the waste water suction fixed bed catalytic reactor that prepare by volume pump, in reaction tower, blast air by blower fan in the reaction process, handle after directly enter the next stage biochemical system behind the wastewater to reach standard that aeration is handled; Primary oxidant ClO wherein
2The concentration of the aqueous solution is 0.03%～5%, ClO
2Dosage in waste water is 5%～20% of a waste water COD concentration; Secondary oxidizer adopts O
2, air, H
2O
2Or wherein several, the volume ratio of secondary oxidizer and waste water is controlled at 100～110: 1.
2. the treatment process of a kind of pure terephthalic acid's factory effluent as claimed in claim 1 is characterized in that primary oxidant ClO
2The preferred concentration of the aqueous solution is 0.07%～0.15% to be 700mg/L～1500mg/L.
3. the treatment process of a kind of pure terephthalic acid's factory effluent as claimed in claim 1 is characterized in that ClO
2The preferred concentration range for of the dosage in waste water is 7%～10%.
4. the treatment process of a kind of pure terephthalic acid's factory effluent as claimed in claim 1, it is characterized in that settling process adopts continuous settling methods to separate contained solid granules such as terephthalic acid in the waste water, the residence time, preferable range was 20～30 hours at 10～60 hours.
5. the treatment process of a kind of pure terephthalic acid's factory effluent as claimed in claim 1 is characterized in that filtration procedure adopts suction method or filter press technique to remove contained solid particulate in the waste water.
6. the treatment process of a kind of pure terephthalic acid's factory effluent as claimed in claim 1 is characterized in that taking aeration to handle through the waste water behind the catalyzed oxidation.
7. the treatment process of a kind of pure terephthalic acid's factory effluent as claimed in claim 1 is characterized in that employed oxide catalyst is the metal-salt mixture that loads on the activated carbon granule.
8. the treatment process of a kind of pure terephthalic acid's factory effluent as claimed in claim 7, the carrier active carbon that it is characterized in that described oxide catalyst is particulate state or column, its specific surface area is 450～3500m
2/ g, pore volume are 0.3～0.85ml/g, and wherein the above particulate mean diameter of 90wt% is 3～5mm.
9. the treatment process of a kind of pure terephthalic acid's factory effluent as claimed in claim 7 is characterized in that the oxidation catalyst activity components system is Lewis hydrochlorate A
XB
YIn one or more, A=Al wherein
3+, Zn
2+, Fe
3+, Sn
2+, Co
3+, Cu
2+, Sb
3+, Ti
3+, Mn
4+, Pb
2+, Mg
2+, Ni
3+, B=Cl
-, Br
-, F
-, SO
4 2-, CH
3COO, NO
3 -
10. the treatment process of a kind of pure terephthalic acid's factory effluent as claimed in claim 7 is characterized in that carrier active carbon fills in fixed-bed reactor with the form of filling, and the filling voidage is 10～20%; Supported catalyst dipping concentration is 2～16%, and wherein most preferred range 5～6%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006100415611A CN100427415C (en) | 2006-09-15 | 2006-09-15 | Process for treating waste water of refined terephthalic acid |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006100415611A CN100427415C (en) | 2006-09-15 | 2006-09-15 | Process for treating waste water of refined terephthalic acid |
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| Publication Number | Publication Date |
|---|---|
| CN1927745A true CN1927745A (en) | 2007-03-14 |
| CN100427415C CN100427415C (en) | 2008-10-22 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2006100415611A Expired - Fee Related CN100427415C (en) | 2006-09-15 | 2006-09-15 | Process for treating waste water of refined terephthalic acid |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101941769A (en) * | 2010-09-10 | 2011-01-12 | 常州大学 | Method for pre-treating alkali PTA wastewater by using combined flocculating agent |
| CN106348499A (en) * | 2016-10-26 | 2017-01-25 | 浙江奇彩环境科技股份有限公司 | Treatment method of garbage leachate concentrated solution |
| CN112830597A (en) * | 2020-12-31 | 2021-05-25 | 何蕾 | Polyester wastewater treatment method |
| CN113461249A (en) * | 2020-03-30 | 2021-10-01 | 中石化南京化工研究院有限公司 | Terephthalic acid production wastewater treatment method based on biological synergistic means |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1039784A (en) * | 1989-06-20 | 1990-02-21 | 北京市环境保护科学研究所 | Pure terephthalic acid (PTA) Wastewater Treatment |
| CN1049408C (en) * | 1994-12-01 | 2000-02-16 | 中国石油化工总公司抚顺石油化工研究院 | Treatment for wastewater from production of fine terephthalic acid |
| CN1182053C (en) * | 2000-03-31 | 2004-12-29 | 郝彤 | Process for treating waste water generated in production of refined terephthalic acid |
-
2006
- 2006-09-15 CN CNB2006100415611A patent/CN100427415C/en not_active Expired - Fee Related
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101941769A (en) * | 2010-09-10 | 2011-01-12 | 常州大学 | Method for pre-treating alkali PTA wastewater by using combined flocculating agent |
| CN101941769B (en) * | 2010-09-10 | 2012-11-28 | 常州大学 | Method for pre-treating alkali PTA wastewater by using combined flocculating agent |
| CN106348499A (en) * | 2016-10-26 | 2017-01-25 | 浙江奇彩环境科技股份有限公司 | Treatment method of garbage leachate concentrated solution |
| CN106348499B (en) * | 2016-10-26 | 2019-06-11 | 浙江奇彩环境科技股份有限公司 | A kind of processing method of landfill leachate concentration liquid |
| CN113461249A (en) * | 2020-03-30 | 2021-10-01 | 中石化南京化工研究院有限公司 | Terephthalic acid production wastewater treatment method based on biological synergistic means |
| CN112830597A (en) * | 2020-12-31 | 2021-05-25 | 何蕾 | Polyester wastewater treatment method |
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| Publication number | Publication date |
|---|---|
| CN100427415C (en) | 2008-10-22 |
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| C14 | Grant of patent or utility model | ||
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Assignee: Longcheng Chemical Co., Ltd., Haian County Assignor: Jiangsu Polytechnic University Contract record no.: 2010320000568 Denomination of invention: Process for treating waste water of refined terephthalic acid Granted publication date: 20081022 License type: Exclusive License Open date: 20070314 Record date: 20100510 |
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Granted publication date: 20081022 Termination date: 20110915 |