CN103708641A - Process for decoloration degradation of industrial organic wastewater through tandem catalytic oxidation - Google Patents
Process for decoloration degradation of industrial organic wastewater through tandem catalytic oxidation Download PDFInfo
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- CN103708641A CN103708641A CN201310451055.XA CN201310451055A CN103708641A CN 103708641 A CN103708641 A CN 103708641A CN 201310451055 A CN201310451055 A CN 201310451055A CN 103708641 A CN103708641 A CN 103708641A
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Abstract
The present invention relates to a process for treating industrial organic wastewater through tandem catalytic oxidation, and belongs to the technical field of environmental protection. According to the process for treating industrial organic wastewater through tandem catalytic oxidation, pre-treated industrial organic wastewater is subjected to the tandem and synergetic manner of ozonization catalysis and hydrogen peroxide oxidation catalysis so as to achieve synergism between the oxidants and the rapid treatment on the complex organic pollutants, wherein in the first catalytic oxidation process, a large number of hydroxyl radicals produced by catalytic oxidation of ozone are adopted to carry out oxidation decomposition on the organic matters in the wastewater, the remaining ozone and the remaining organic pollutants enter the second catalytic decomposition process of hydrogen peroxide so as to degrade the organic pollutants and activate the degradation effect of hydrogen peroxide and ozone, such that the rapid organic pollutant degradation purpose is achieved; and the treatment capability on the difficultly-degraded organic pollutants is improved, the utilization efficiency of the oxidants is increased, and the operation cost is effectively reduced.
Description
Technical field
The present invention relates to a kind of series connection catalyzed oxidation decolored degradation industrial organic waste water technique, belong to environmental protection technical field.
Background technology
The waste water of industrial park is more unmanageable waste water, its complicated component of originating, and organic pollutant is wherein often refractory organic, intractability is large.The COD of this part is often greater than 2000mg/L, and with benzene ring structure, the organic pollutant of stable in properties occupies large percentage, has therefore increased the difficulty of processing.At present, industrial park waste water adopts single-oxidizer treatment process: H
2o
2catalytic oxidation or O
3catalytic oxidation, is decomposed into small organic molecule or CO by the oxidation operation in waste water
2and H
2o, thus remove the organic pollutant in waste water.Traditional chemical oxidization method only depends on the oxidation capacity of oxygenant often can not reach desirable oxidation effectiveness, so use some supplementary meanss to improve oxidation efficiency.There is UV/O
3, UV/H
2o
2, the catalytic oxidation such as Fenton method, improved the processing efficiency of chemical oxidization method.Also occurred that other treating method is as methods such as catalytic wet oxidations simultaneously, if the Wet Oxidation Process (WAO) of F.J.Zimmermann proposition in 1958 is to make oxygenant with air or pure oxygen, under high temperature (150～350 ℃), high pressure (0.5MPa～28MPa) condition, by the hardly degraded organic substance oxygenolysis in waste water, be small organic molecule or CO
2and H
2o.Owing to having used higher temperature and pressure in WAO technology, all brought sizable difficulty therefore to manufacture, the operation of equipment.The operational conditions of High Temperature High Pressure is the major cause that this technology can not be promoted always.Fenton in 1894 finds can produce hydroxyl radical free radical (OH) after ferrous iron and hydrogen peroxide mix, .OH because it has high oxidizing potential (2.8V), its oxidation capacity is extremely strong, can there is chain reaction fast with most organic pollutants, non-selectivity objectionable impurities is oxidized to CO
2, H
2o or mineral salt, non-secondary pollution.Fenton reagent has solved the problem that catalyzed oxidation technology is used at normal temperatures and pressures.Significantly improve processing efficiency.After the eighties in 20th century, the application of the catalysis water technology of ozone and hydrogen peroxide in trade effluent becomes the main method that trade effluent improves biodegradability, effectively reduces pollution concentration gradually.In the process of using, can be because oxygenant be active different to the processing of different organic pollutants while utilizing merely the complicated organic pollutant of catalyst oxide treatment, cause the problems such as treatment types is limited.The organic waste water of industrial organic waste water, particularly industrial park, its complicated component of originating, organic pollutant is wherein often refractory organic, intractability is large, is organic wastewater with difficult degradation thereby.The COD of this part is often greater than 2000mg/L, and with benzene ring structure, the organic pollutant of stable in properties occupies large percentage, has therefore increased the difficulty of processing.
So the method that multiple method for oxidation coupling is processed has obtained application gradually in industrial practical application, as added FeSO in early stage
4, decolouring precipitation, and then the technique of carrying out oxygenant oxidation, but for the synergy of considering between different oxygenants, improve oxygenant utilization ratio, improve the technique for the treatment of effect, also have not seen reported.
Summary of the invention
For above-mentioned existing problems, the object of the present invention is to provide a kind of series connection catalyzed oxidation decolored degradation industrial organic waste water technique, to achieve these goals, technical solution of the present invention is as follows: a kind of process for treating industrial organic waste water by serial catalytic oxidization, the catalytic oxidation treatment mode that organic waste water after preprocessing process is adopted is one-level catalyzed oxidation and secondary concerted catalysis oxidation, described one-level catalyzed oxidation refers to that industrial organic waste water enters first step catalyzed oxidation pond body, Chi Tizhong is water in mass ratio: one-level catalyzer=1000:1 places catalyzer, after having intake, add ozone, ozone add-on is 100～800g/Th, reaction times is 30 minutes, waste water first step catalyzed oxidation internal recycle in pond, working cycle continues 40 minutes, make waste water and catalysis enter abundant contact reacts, first step catalytic oxidation finishes,
Described secondary concerted catalysis oxidation refers to that the industrial organic waste water after one-level catalyzed reaction drains into second stage circulatory pool from first step reaction tank, at this Chi Tizhong water in mass ratio: second catalyst=1100:1 places catalyzer, and unreacted ozone is collected, aeration enters catalyzed oxidation pond, second stage body, pumping into concentration is 20% hydrogen peroxide 100～700g/Th, stop to process 30 minutes, during carry out internal recycle, working cycle continues 30 minutes, and second stage catalytic oxidation finishes.
Described one-level catalyzer is for take gac as carrier, and surface recombination is containing manganese metal ion, and compounding quantity is 3g/kg.
Described second catalyst is for take gac as carrier, surface recombination ferrous metal ion, and compounding quantity is 5g/kg.
Described catalyzer, its preparation method adopts pickling process, the steps include: first to prepare the salts solution that contains respective concentration metal cation component, gac is put into salts solution and flood for some time, the catalyzer that gets product of solution evaporation is dry, roasting afterwards.
Owing to adopting above technical scheme, process for treating industrial organic waste water by serial catalytic oxidization of the present invention, adopt catalytic ozonation and the series connection of catalysis dioxygen aquation and collaborative mode, by multiple oxidizer catalytic method series connection, realized working in coordination with between oxygenant, described series connection catalytic oxidation technique is at normal temperature, under condition of normal pressure, the first catalyzer is catalytic ozonation process in first catalytic oxidation process: use immobilized catalyst catalytic decomposition ozone, generate great amount of hydroxy group free radical (OH), utilize OH redox potential and Electron Affinities to interrupt the chromophore in organic pollutant molecule structure, band look organic pollutant in water is decoloured fast, and make a position C-H key of polymeric oxide in waste water, β-C key, γ-C key, C-C is broken into low molecular compound, thereby the organism in waste water is carried out to oxygenolysis, fast degradation organic cod.Remaining ozone and remaining organic pollutant enter second catalytic decomposition process.In this process, adopt the second catalyst to decompose hydrogen peroxide, produce hydroxyl radical free radical degraded oxidation residue organic pollutant, due to the ozone and the hydrogen peroxide generation chain reaction that enter in this process, produce more free radical, the Degradation of having strengthened hydrogen peroxide and ozone, has strengthened synergistic effect, reaches the object of fast degradation organic pollutant.
Process for treating industrial organic waste water by serial catalytic oxidization of the present invention, has not only improved the processing efficiency of reason Persistent organic pollutants, and has improved the utilization ratio of oxygenant; Can effectively reduce running cost, the Application Areas of expansion technique.The catalytic oxidation treatment method that it has solved the single employing hydrogen peroxide of existing industrial organic waste water or ozone is subject to the problem that kind of waste water limits, running cost is high, operation operation is complicated.The present invention is applied under equal operational conditions, can increase substantially industrial organic waste water processing efficiency, reduce equipment investment cost and running cost, make it to be applicable to industrial organic waste water widely, as the processing of the kinds such as paper waste, textile printing and dyeing wastewater or agricultural chemicals waste water.
accompanying drawing explanation
Accompanying drawing 1 is a kind of process for treating industrial organic waste water by serial catalytic oxidization schema.
embodiment
Embodiment mono-:
By above-mentioned technical process: described organic waste water is pharmacy waste water, and index is: treatment capacity 1T, concentration is COD:2000mg/L; Its organic waste water pre-treatment comprise to waste water all with aeration flow process and in and coagulating sedimentation flow process, all and aeration flow process adopt equal and aeration tank, all with aeration tank control air aeration intensity 7m
3/ m
2.h, fully all with; In and coagulating sedimentation flow process adopt in and coagulative precipitation tank, at neutral zone, adopt trip valve to add white lime or hydrochloric acid or salt acid for adjusting pH value, control pH value 6～9, the follow-up 0.5% coagulant aids PAC that adds, control dosage 8mg/L; By pretreatment technology, remove most suspended substances and the oil content in waste water.
Organic waste water after preprocessing process is entered to first step catalyzed oxidation pond body through intermediate pool, and it is the compound activated-carbon catalyst containing manganese metal ion of 3g/kg that Chi Tizhong places 1000g charge capacity.After having intake, add ozone, ozone add-on is 700g/Th, and the reaction times is 30 minutes, waste water first step catalyzed oxidation internal recycle in pond, and working cycle continues 40 minutes, makes waste water and catalysis enter abundant contact reacts, and first step catalytic oxidation finishes;
Industrial organic waste water after one-level catalyzed reaction drains into second stage reaction tank from first step reaction tank, and it is the activated-carbon catalyst of the compound ferrous metal ion of 5g/kg that Chi Tizhong places 910g charge capacity.And unreacted ozone is collected, aeration enters catalyzed oxidation pond, second stage body, pumps into concentration and be 20% hydrogen peroxide 800g/Th, stop and process 30 minutes, during carry out internal recycle, working cycle continues 30 minutes, second stage catalytic oxidation finishes.
Water treatment process finishes; Effluent index is: treatment capacity 1T, concentration is COD:800mg/L
Embodiment bis-:
By above-mentioned technical process: described organic waste water is pharmacy waste water, index is: treatment capacity 1T, concentration is COD:2000mg/L, its organic waste water pre-treatment comprise to waste water all with aeration flow process and in and coagulating sedimentation flow process, all adopt all and aeration tank with aeration flow process, all control air aeration intensity 6m with aeration tank
3/ m
2.h, fully all with; In and coagulating sedimentation flow process adopt in and coagulative precipitation tank, at neutral zone, adopt trip valve to add white lime or salt acid for adjusting pH value, control pH value 6～9, the follow-up 0.5% coagulant aids PAC that adds, control dosage 5mg/L; By pretreatment technology, remove most suspended substances and the oil content in waste water.
Organic waste water after preprocessing process is entered to first step catalyzed oxidation pond body through intermediate pool, and it is the compound activated-carbon catalyst containing manganese metal ion of 3g/kg that Chi Tizhong places 1000g charge capacity.After having intake, add ozone, ozone add-on is 400g/Th, and the reaction times is 30 minutes, waste water first step catalyzed oxidation internal recycle in pond, and working cycle continues 40 minutes, makes waste water and catalysis enter abundant contact reacts, and first step catalytic oxidation finishes;
Industrial organic waste water after one-level catalyzed reaction drains into second stage reaction tank from first step reaction tank, and it is the activated-carbon catalyst of the compound ferrous metal ion of 5g/kg that Chi Tizhong places 910g charge capacity.And unreacted ozone is collected, aeration enters catalyzed oxidation pond, second stage body, pumps into concentration and be 20% hydrogen peroxide 500g/Th, stop and process 30 minutes, during carry out internal recycle, working cycle continues 30 minutes, second stage catalytic oxidation finishes.
Water treatment process finishes; Effluent index is: treatment capacity 1T, concentration is COD:1000mg/L
Embodiment tri-:
By above-mentioned technical process: described organic waste water is pharmacy waste water, index is: treatment capacity 1T, concentration is COD:2000mg/L, its organic waste water pre-treatment comprise to waste water all with aeration flow process and in and coagulating sedimentation flow process, all adopt all and aeration tank with aeration flow process, all control air aeration intensity 1m with aeration tank
3/ m
2.h, fully all with; In and coagulating sedimentation flow process adopt in and coagulative precipitation tank, at neutral zone, adopt trip valve to add white lime or salt acid for adjusting pH value, control pH value 6～9, the follow-up 0.5% coagulant aids PAC that adds, control dosage 1mg/L; By pretreatment technology, remove most suspended substances and the oil content in waste water.
Organic waste water after preprocessing process is entered to first step catalyzed oxidation pond body through intermediate pool, and it is the compound activated-carbon catalyst containing manganese metal ion of 3g/kg that Chi Tizhong places 1000g charge capacity.After having intake, add ozone, ozone add-on is 100g/Th, and the reaction times is 30 minutes, waste water first step catalyzed oxidation internal recycle in pond, and working cycle continues 40 minutes, makes waste water and catalysis enter abundant contact reacts, and first step catalytic oxidation finishes;
Industrial organic waste water after one-level catalyzed reaction drains into second stage reaction tank from first step reaction tank, and it is the activated-carbon catalyst of the compound ferrous metal ion of 5g/kg that Chi Tizhong places 910g charge capacity.And unreacted ozone is collected, aeration enters catalyzed oxidation pond, second stage body, pumps into concentration and be 20% hydrogen peroxide 100g/Th, stop and process 30 minutes, during carry out internal recycle, working cycle continues 30 minutes, second stage catalytic oxidation finishes.
Water treatment process finishes; Effluent index is: treatment capacity 1T, concentration is COD:1800mg/L
Embodiment tetra-:
By above-mentioned technical process: described organic waste water is dyeing waste water, index is: treatment capacity 1T, concentration is COD:2000mg/L, its organic waste water pre-treatment comprise to waste water all with aeration flow process and in and coagulating sedimentation flow process, all adopt all and aeration tank with aeration flow process, all control air aeration intensity 4m with aeration tank
3/ m
2.h, fully all with; In and coagulating sedimentation flow process adopt in and coagulative precipitation tank, at neutral zone, adopt trip valve to add white lime or salt acid for adjusting pH value, control pH value 6～9, the follow-up 0.5% coagulant aids PAC that adds, control dosage 8mg/L; By pretreatment technology, remove most suspended substances and the oil content in waste water.
Organic waste water after preprocessing process is entered to first step catalyzed oxidation pond body through intermediate pool, and it is the compound activated-carbon catalyst containing manganese metal ion of 3g/kg that Chi Tizhong places 1000g charge capacity.After having intake, add ozone, ozone add-on is 800g/Th, and the reaction times is 30 minutes, waste water first step catalyzed oxidation internal recycle in pond, and working cycle continues 40 minutes, makes waste water and catalysis enter abundant contact reacts, and first step catalytic oxidation finishes;
Industrial organic waste water after one-level catalyzed reaction drains into second stage reaction tank from first step reaction tank, and it is the activated-carbon catalyst of the compound ferrous metal ion of 5g/kg that Chi Tizhong places 910g charge capacity.And unreacted ozone is collected, aeration enters catalyzed oxidation pond, second stage body, pumps into concentration and be 20% hydrogen peroxide 800g/Th, stop and process 30 minutes, during carry out internal recycle, working cycle continues 30 minutes, second stage catalytic oxidation finishes.
Water treatment process finishes; Effluent index is: treatment capacity 1T, concentration is COD:800mg/L
Embodiment five:
By above-mentioned technical process: described organic waste water is paper waste, index is: treatment capacity 1T, concentration is COD:2000mg/L, its organic waste water pre-treatment comprise to waste water all with aeration flow process and in and coagulating sedimentation flow process, all adopt all and aeration tank with aeration flow process, all control air aeration intensity 7m with aeration tank
3/ m
2.h, fully all with; In and coagulating sedimentation flow process adopt in and coagulative precipitation tank, at neutral zone, adopt trip valve to add white lime or salt acid for adjusting pH value, control pH value 6～9, the follow-up 0.5% coagulant aids PAC that adds, control dosage 2mg/L; By pretreatment technology, remove most suspended substances and the oil content in waste water.
Organic waste water after preprocessing process is entered to first step catalyzed oxidation pond body through intermediate pool, and it is the compound activated-carbon catalyst containing manganese metal ion of 3g/kg that Chi Tizhong places 1000g charge capacity.After having intake, add ozone, ozone add-on is 800g/Th, and the reaction times is 30 minutes, waste water first step catalyzed oxidation internal recycle in pond, and working cycle continues 40 minutes, makes waste water and catalysis enter abundant contact reacts, and first step catalytic oxidation finishes;
Industrial organic waste water after one-level catalyzed reaction drains into second stage reaction tank from first step reaction tank, and it is the activated-carbon catalyst of the compound ferrous metal ion of 5g/kg that Chi Tizhong places 910g charge capacity.And unreacted ozone is collected, aeration enters catalyzed oxidation pond, second stage body, pumps into concentration and be 20% hydrogen peroxide 600g/Th, stop and process 30 minutes, during carry out internal recycle, working cycle continues 30 minutes, second stage catalytic oxidation finishes.
[0021] water treatment process finishes; Effluent index is: treatment capacity 1T, concentration is COD:800mg/L.
Claims (4)
1. a process for treating industrial organic waste water by serial catalytic oxidization, it comprises a kind ofly carries out pre-treatment and treatment by catalytic oxidation to industrial organic waste water, it is characterized in that: the catalytic oxidation treatment mode that the organic waste water after preprocessing process is adopted is divided into one-level catalyzed oxidation and secondary concerted catalysis oxidation, described one-level catalyzed oxidation refers to that industrial organic waste water enters first step catalyzed oxidation pond body, Chi Tizhong is water in mass ratio: one-level catalyzer=1000:1 places catalyzer, after having intake, add ozone, ozone add-on is 100～800g/Th, reaction times is 30 minutes, waste water first step catalyzed oxidation internal recycle in pond, working cycle continues 40 minutes, make waste water and catalysis enter abundant contact reacts, first step catalytic oxidation finishes.
2. described in, secondary concerted catalysis oxidation refers to that the industrial organic waste water after one-level catalyzed reaction drains into second stage circulatory pool from first step reaction tank, Chi Tizhong is water in mass ratio: second catalyst=1100:1 places catalyzer, and unreacted ozone is collected, aeration enters catalyzed oxidation pond, second stage body, pumping into concentration is 20% hydrogen peroxide 100～700g/Th, stop to process 30 minutes, during carry out internal recycle, working cycle continues 30 minutes, and second stage catalytic oxidation finishes.
3. process for treating industrial organic waste water by serial catalytic oxidization according to claim 1, is characterized in that, described one-level catalyzer is for take gac as carrier, and surface recombination is containing manganese metal ion, and compounding quantity is 3g/kg.
4. process for treating industrial organic waste water by serial catalytic oxidization according to claim 1, is characterized in that, described second catalyst is for take gac as carrier, surface recombination ferrous metal ion, and compounding quantity is 5g/kg.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104211263A (en) * | 2014-09-23 | 2014-12-17 | 唐国民 | Treating method of refractory organics in biochemical tailrace of traditional Chinese medicine wastewater |
| CN105858950A (en) * | 2016-04-11 | 2016-08-17 | 绍兴柯桥江滨水处理有限公司 | Dyeing wastewater advanced treatment method and device by using ozone, oxydol and activated carbon |
| CN111499094A (en) * | 2020-04-13 | 2020-08-07 | 南京卓越环保科技有限公司 | Harmless treatment method of high-concentration sodium pyridinol acid water |
-
2013
- 2013-09-29 CN CN201310451055.XA patent/CN103708641A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104211263A (en) * | 2014-09-23 | 2014-12-17 | 唐国民 | Treating method of refractory organics in biochemical tailrace of traditional Chinese medicine wastewater |
| CN105858950A (en) * | 2016-04-11 | 2016-08-17 | 绍兴柯桥江滨水处理有限公司 | Dyeing wastewater advanced treatment method and device by using ozone, oxydol and activated carbon |
| CN111499094A (en) * | 2020-04-13 | 2020-08-07 | 南京卓越环保科技有限公司 | Harmless treatment method of high-concentration sodium pyridinol acid water |
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