CN102951759A - Method for treating highly-difficult-to-treat industrial wastewater through catalytic oxidation and micro-electrolysis - Google Patents
Method for treating highly-difficult-to-treat industrial wastewater through catalytic oxidation and micro-electrolysis Download PDFInfo
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Abstract
The invention relates to a wastewater treatment method, in particular to a wastewater treatment method through catalytic oxidation and micro-electrolysis. The wastewater treatment method comprises the following steps of: 1, iron and carbon pretreatment; 2, micro-electrolysis reaction: regulating pH (potential of hydrogen) of wastewater to 2-3 by using acid, feeding pretreated iron chips and pretreated activated carbon according to weight ratio of the iron chips to the activated carbon being 1:1 and ratio of the total weight of the iron chips and the activated carbon to the weight of the wastewater being 1:3, conducting aeration by using compressed air, adding H2O2 according to ratio being 1/1000 when pH reaches 4-5, stopping reaction till pH reaches 6, draining the wastewater into an intermediate pond and adding polyacrylamide (PAM) for settlement; and 3, catalytic oxidation: after settlement, feeding the wastewater into a reaction pond with an agitator, regulating pH to 3-4 by using acid, adding powder activated carbon and 4A molecular sieves according to ratio being 0.2/1000, then adding oxidant H2O2 according to ratio being 2.1/1000, keeping reaction for 60min, and after the reaction is stopped, regulating pH to 6-7 by using NaOH solution and adding PAM for settlement. The method for treating highly-difficult-to-treat industrial wastewater through catalytic oxidation and micro-electrolysis has the advantages that the treatment effect of the highly-difficult-to-treat industrial wastewater can be improved and the application scope is wide.
Description
Technical field
The present invention relates to a kind of method of wastewater treatment, be specifically related to comprise the method for wastewater treatment of catalyzed oxidation and microelectrolysis processing step.
Background technology
In recent years, along with the fast development of China's industry, produced the great organic industrial sewage of a large amount of intractabilities, be called for short: highly difficult trade effluent.This class waste water has following characteristics: the one, and complicated component, and also molecular chain is firm, is difficult to biochemical degradation; The 2nd, COD
CrHeight, general COD
CrFrom mg/L more than 10000 to hundreds of thousands of mg/L; The 3rd, colourity is high, from several thousand times to several ten thousand times; The 4th, this class wastewater toxicity is large, and is serious to environmental hazard, can't governance for reaching standard with traditional technology; The 5th, this class wastewater flow rate is little, does not wait from several tons/days to tens tons/day, and the equipment investment cost ratio of processing is excessive.
This type of waste water is especially common in industries such as chemical industry, bio-pharmaceuticals, printing and dyeing, furniture, pickles, petrochemical compleies.
And existing treatment process to this type of waste water is also very complicated, and cost is high, perhaps only can implement for certain waste water, and range of application is narrow.
It is that effect is a kind of preferably comparatively speaking that catalyzed oxidation adds the microelectrolysis processing technology; Existing catalyzed oxidation and micro electrolysis tech cardinal principle are:
Catalyzed oxidation:
Adopt the Fenton reagent oxidation: regulate waste water PH to 4, add ferrous sulfate: 3-4g/L waste water, H
2O
2: 2-3g/L waste water, stirring reaction 1h regulates PH to 6-7, uses the PAM sedimentation.The principal reaction formula:
Fe
2 ++H
2O
2→Fe3
++OH+OH
-
Fe3
++H?H
2O
2→Fe
2 ++.OH
2+H
+
Fe
2 +With H
2O
2Reaction generates the .OH radical rapidly, and the .OH radical is the extremely strong oxygenant of oxidation capacity in the aqueous solution, with the organic molecule oxygenolysis in the waste water.
Little electrolysis:
Utilize golden corrosion principle, with Fe
2 +Be anode, take gac as negative electrode, under acidic conditions, form the galvanic cell reaction, claim again internal electrolysis, Filtration with Iron Filings, this technique is to be applied in the waste water treatment at 20 century 70s,
Electrode reaction is as follows:
Anode (Fe): Fe-2e → Fe
2+Eo-(Fe
2+/ Fe)=0.44V
Negative electrode (C): 2H
++ 2e → 2[H] → H
2↑ (in the acidic solution) Eo (H
+/ H
2)=OV
O during aerobic
2+ 4H
++ 4e → 2H
2In the O(acidic solution) EO-(O
2/ H
2O)=1.23V
O
2+ 2H
2O+4e → 4OH-(in neutrality or the basic solution) EO-(O
2/ H
20)=0.41V
This reaction is to have utilized galvanic cell reaction, redox reaction and Fe
3 +Coagulation be principle, make organism in the waste water obtain degraded.
Above-mentioned catalyzed oxidation adds microelectrolysis processing technology Main Problems:
1, the waste water COD degraded that intractability is high is poor, only has 30-40%, and particularly high slat-containing wastewater is poorer;
2, sediment is many, has increased workload to postprocessing working procedures, has increased processing cost;
3, little electrolytic iron and carbon easily harden, and produce channeling and have reduced treatment effect.
Summary of the invention
Main purpose of the present invention provides a kind of catalyzed oxidation and adds the method that highly difficult trade effluent is administered in little electrolysis, and the method can improve treatment effect and the use range of highly difficult waste water extensive.
For achieving the above object, the technical solution adopted in the present invention is: a kind of catalyzed oxidation adds the method that highly difficult trade effluent is administered in little electrolysis, and step comprises:
1), iron carbon pre-treatment:
Iron filings are soaked oil removing with liquid caustic soda clean, then soak the removal surface passivated membrane with diluted acid and clean; Granular carbon is dipped to not a half hour with clear water;
2), micro-electrolysis reaction:
Waste water is regulated PH to 2-3 with acid; Pretreated iron filings and gac are fed intake by 1:3 by weight 1:1, iron filings and gac total amount and waste water weight ratio; With the pressurized air aerated reaction, the ratio by weight 1/1000 when pH value reaches 4-5 adds H
2O
2, be reacted to again PH and reach 6 o'clock stopped reaction, waste water is put into intermediate pool add the PAM sedimentation;
3), catalyzed oxidation:
Waste water after the precipitation enters in the reaction tank of band stirring, transfers pH value to reach 3-4 with acid, adds Powdered Activated Carbon, and add-on is weight ratio 0.8/1000; Add oxygenant 4A molecular sieve, add-on is weight ratio 0.2/1000 again; Add again oxygenant H
2O
2, add-on is weight ratio 2.1/1000; Reaction 60min; Reaction stops rear with NaOH solution accent pH value 6-7, PAM sedimentation.
Used acid-base reagent mainly in order to regulate pH value, can done the replacement that much is equal to.
Further, described iron filings are cast iron filing.
Further, described gac soaked 2 hours with clear water.
Further, described micro-electrolysis reaction carries out in the electrolysis tower.
Further, in the described pre-treatment, iron filings are cleaned, are then soaked 30min with 3% dilute hydrochloric acid with 10%NaOH solution soaking 10min oil removing, and it is clean to remove surface gizzardization film.
Further, begin sampling behind the described aerated reaction 40min and survey pH value.
Further, to reach PH be 4-5 to described aerated reaction, add H
2O
2After react again 20-30min.
Useful technique effect of the present invention:
1, extra-high-speed difficulty waste water COD and colourity degraded are reached 70-90%, and all effective to all highly difficult organic wastewater degraded.
2, processed waste water BOD/COD is reached more than 0.3, for biochemical treatment creates favorable conditions.
3, sediment weight reduces 1/3rd than prior art, reduce mud dehydration workload and processing cost.
4, effectively solve the Fe-C plate junction phenomena, improve treatment effect.
Embodiment
For making the clearer technical scheme of the present invention of art technology and technique effect, the below provides the preferred embodiments of the present invention, but technology of the present invention is not limited in following embodiment.
Embodiment
Utilize method of the present invention that the waste water of producing 5 kinds of variant productions is processed, Raw performance sees Table 1.
Waste water quality before table 1 is processed
| The waste water title | COD/mg/L | BOD/mg/L | PH | Colourity/doubly | SS/mg/L |
| Chlorine nitre | 15000 | 458 | 0.5 | 12000 | 2500 |
| Sulphadiazine Sodium | 12000 | 340 | 7 | 2000 | 1500 |
| Oil of mirbane | 9500 | 310 | 6 | 11000 | 2100 |
| Agricultural chemicals | 120000 | 685 | 6.5 | 5000 | 2050 |
| Furniture | 11000 | 450 | 6.2 | 200 | 3000 |
Treatment process:
1), iron carbon pre-treatment
Cast iron filing is cleaned, then soaked 30min with 3% dilute hydrochloric acid with 10%NaOH solution soaking 10min oil removing, and it is clean for subsequent use to remove surface passivated membrane.It is for subsequent use that granular carbon is soaked 2h with clear water.
2), micro-electrolysis reaction
Pretreated iron filings and gac are dropped in the electrolysis tower by weight the 1:1 ratio, and iron filings and gac gross weight and waste water weight feed intake in the ratio of 1:3; Waste water transfers PH to 2-3 with 40% dilute hydrochloric acid first before sending into the electrolysis tower; With pressurized air aerated reaction 40min, pH value is surveyed in sampling in the electrolysis tower, adds H when pH value reaches 4-5 in 1/1000 ratio
2O
2, reacting again 20min and begin the sampling detection, stopped reaction when PH reaches 6 is put into intermediate pool with waste water and is added the PAM sedimentation.
3) catalyzed oxidation
The water outlet of PAM sedimentation is squeezed in the reaction tank of band stirring, transfers pH value to 3-4 with 40% dilute hydrochloric acid, adds Powdered Activated Carbon as catalyzer, and add-on is 0.8/1000 by weight; Add oxygenant 4A molecular sieve, add-on is 0.2/1000 by weight again; Add again oxygenant H
2O
2, add-on is 2.1/1000 by weight; Reaction 60min, reaction stops rear with 40%NaOH solution accent pH value 6-7, uses the PAM sedimentation.
Get the supernatant liquor check.Potassium dichromate process side COD; Biochemical process was surveyed BOD on 5th; Extension rate method colour examining degree.The results are shown in Table 2.
Effluent quality after table 2 is processed
Contrast table 1 and as seen from Table 2: the present invention processes the waste water of chlorine nitre, Sulphadiazine Sodium, oil of mirbane, agricultural chemicals, furniture production: COD clearance average out to 93.9%; Chroma removal rate average out to 93.2%; And BOD/COD ratio from raw wastewater pool 0.03 bring up to 0.3, the biodegradability of waste water improves 10 times, but reach the waste water biochemical treatment index that industry is generally acknowledged, for favourable condition has been created in lower operation biochemical treatment.Final outflow water can reach the comprehensive first discharge standard with country.
The principle analysis of the inventive method
The present invention obtains preferably treatment effect to above-mentioned 5 kinds of highly difficult organic waste waters, and this is because increase oxygenant H in little electrolysis
2O
2, in catalyzed oxidation, having changed existing Fenton oxidation style, degradation effect improves, and sediment weight reduced 1/3, and its possible reaction mechanism is as follows:
Little mechanism of electrolysis
Redox reaction: Fe
2+That the active metal in acidic aqueous solution following reaction can occur:
Fe+2H
+——Fe
2++H
2↓
When having oxygenant in the water, Fe
2+Can further be oxidized to Fe
3+Can know that from the electropotential of iron the metal that comes the iron back in the metal activity series table might be cemented out and be deposited on the surface of iron by iron.Equally, the ion that other oxidisability are stronger or compound also can by iron or ferrous ion be reduced into toxicity less reduction-state.
The galvanic cell reaction: cast iron is the alloy of iron and carbon, namely by pure iron and Fe
3C and some impurity form.Iron carbide in the cast iron is minimum particle, is dispersed in the iron.Iron carbide is lower than the corrosion tendency of iron.Therefore, just consisted of thousands of tiny microbatterys when cast iron is immersed in the water, become anode with pure iron, iron carbide and impurity then are negative electrode, the generating electrodes reaction, and this is the microcosmic battery.When the macroscopic view of the gac in system cathode material exists, can form macroscopical battery again, the primary electrode reaction is as follows:
Anodic reaction: Fe-2e---Fe
2+
EO(Fe
2+/Fe)=-0.44v
Cathodic reaction: 2H
++ 2e7---H
2
EO(H
+/H
2)=OV
When O is arranged
2The time:
O
2+4H
++4e——2H
2O
E0(O
2)=1.23V
O
2+ 2H
2O+4e---4OH
-(neutral or alkalescence)
E0(O
2/OH
-)=0.40V
In the environment of slant acidity, cast iron electrode itself and the nascent state H, the Fe that produce
2+Can produce many components Deng all in waste water, redox reaction occurs, the structure of chromophoric group reaches the decolouring purpose in the energy damaged colored waste water.As, to dinitrochlorobenzene waste water, what contain the nitro material in the waste water can all be converted into amido, thereby makes the colourity of waste water reduce BOD
5 days/ COD
CrRise to 0.36mg/L from 0.03, biodegradability significantly improves.
The coagulation of iron:
Under acidic conditions, when processing waste water with iron filings, can produce Fe
2+And Fe
3+, be good flocculation agent, the solution pH value is transferred to alkalescence, and O is arranged
2Can form Fe (OH) when existing
2And Fe(OH)
3Flocculation sediment, react as follows:
Fe
2++2OH
-——8Fe(OH)
2↓
4Fe
2++8OH
-+O
2+2H
2O——4Fe(OH)
3↓
The Fe (OH) that generates
3Be the colloid flocculation agent, its adsorptive power is higher than the Fe (OH) that general medicament hydrolysis obtains
3Adsorptive power.Like this, the insolubles that original suspended substance produces by microbattery reaction in the waste water and the insoluble dyes of colourity all can be by its adsorption-condensations.
The oxygenizement of improved Fenton
In little electrolysis, when PH rises to 4, just satisfy the oxidation requirement of Fenton, this is characteristics part of the present invention, works as Fe
2+With H
2O
2It is very fast that reaction generates the speed of .OH radical, and the .OH radical is the extremely strong oxygenant of oxidation capacity in the aqueous solution, can be with the organic molecule oxygenolysis in the waste water.
Catalyzed oxidation mechanism
Under acidic conditions, take activated carbon .4A molecular sieve as catalyzer, H
2O
2Be oxygenant, impel the oxygenant fast decoupled and produce the .OH radical at the 60min inner catalyst.This radical has very strong oxidisability, organic molecule oxygenolysis and the mineralising in the waste water can be become inorganic molecules.And molecular sieve has higher hole, more is conducive to the .OH radical and attacks organic molecule in hole, the enhancement process effect.
Claims (7)
1. a catalyzed oxidation adds the method that highly difficult trade effluent is administered in little electrolysis, and step comprises:
1), iron carbon pre-treatment:
Iron filings are soaked oil removing with liquid caustic soda clean, then soak the removal surface passivated membrane with diluted acid and clean; Granular carbon is dipped to not a half hour with clear water;
2), micro-electrolysis reaction:
Waste water is regulated PH to 2-3 with acid; Pretreated iron filings and gac are fed intake by 1:3 by weight 1:1, iron filings and gac total amount and waste water weight ratio; With the pressurized air aerated reaction, the ratio by weight 1/1000 when pH value reaches 4-5 adds H
2O
2, be reacted to again PH and reach 6 o'clock stopped reaction, waste water is put into intermediate pool add the PAM sedimentation;
3), catalyzed oxidation:
Waste water after the precipitation enters in the reaction tank of band stirring, transfers pH value to reach 3-4 with acid, adds Powdered Activated Carbon, and add-on is weight ratio 0.8/1000; Add oxygenant 4A molecular sieve, add-on is weight ratio 0.2/1000 again; Add again oxygenant H
2O
2, add-on is weight ratio 2.1/1000; Reaction 60min; Reaction stops the rear NaOH of using solution and transfers pH value to 6-7, the PAM sedimentation.
2. catalyzed oxidation according to claim 1 adds the method that highly difficult trade effluent is administered in little electrolysis, it is characterized in that: described iron filings are cast iron filing.
3. catalyzed oxidation according to claim 1 adds the method that highly difficult trade effluent is administered in little electrolysis, it is characterized in that: described gac soaked 2 hours with clear water.
4. catalyzed oxidation according to claim 1 adds the method that highly difficult trade effluent is administered in little electrolysis, it is characterized in that: described micro-electrolysis reaction carries out in the electrolysis tower.
5. catalyzed oxidation according to claim 1 adds the method that highly difficult trade effluent is administered in little electrolysis, it is characterized in that: in the described pre-treatment, iron filings are cleaned, are then soaked 30min with 3% dilute hydrochloric acid with 10%NaOH solution soaking 10min oil removing, and it is clean to remove surface gizzardization film.
6. catalyzed oxidation according to claim 1 adds the method that highly difficult trade effluent is administered in little electrolysis, it is characterized in that: begin sampling behind the described aerated reaction 40min and survey pH value.
7. catalyzed oxidation according to claim 1 adds the method that highly difficult trade effluent is administered in little electrolysis, it is characterized in that: it is 4-5 that described aerated reaction reaches PH, add H
2O
2After react again 20-30min.
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Cited By (8)
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|---|---|---|---|---|
| CN103318991A (en) * | 2013-07-17 | 2013-09-25 | 重庆泰克环保工程设备有限公司 | Iron-carbon electrolytic filter unit and its water treatment method |
| CN103613250A (en) * | 2013-12-04 | 2014-03-05 | 成都双地环境工程有限公司 | Method for treating pickle wastewater |
| CN105366846A (en) * | 2015-09-11 | 2016-03-02 | 东莞市绿巨人环境科技有限公司 | Method for treating paraquat pesticide wastewater |
| CN106045147A (en) * | 2016-08-05 | 2016-10-26 | 山东明泰环保科技有限公司 | Organic waste water MT polyphase catalytic oxidation device |
| CN106115726A (en) * | 2016-06-18 | 2016-11-16 | 上海应用技术学院 | A kind of preparation method of ferrum carbon modified mesoporous molecular sieve |
| CN106957091A (en) * | 2017-03-03 | 2017-07-18 | 苏文灿 | A kind of processing method of organic industrial sewage |
| CN112755754A (en) * | 2021-01-04 | 2021-05-07 | 深圳市奇信集团股份有限公司 | Aldehyde-removing water-absorbing resin ball and preparation method thereof |
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- 2012-11-13 CN CN 201210453918 patent/CN102951759A/en active Pending
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103318991A (en) * | 2013-07-17 | 2013-09-25 | 重庆泰克环保工程设备有限公司 | Iron-carbon electrolytic filter unit and its water treatment method |
| CN103318991B (en) * | 2013-07-17 | 2015-08-26 | 重庆泰克环保工程设备有限公司 | Iron carbon electrolytic filter device and water treatment method thereof |
| CN103613250A (en) * | 2013-12-04 | 2014-03-05 | 成都双地环境工程有限公司 | Method for treating pickle wastewater |
| CN103613250B (en) * | 2013-12-04 | 2015-09-09 | 成都双地环境工程有限公司 | A kind for the treatment of process of pickle wastewater |
| CN105366846A (en) * | 2015-09-11 | 2016-03-02 | 东莞市绿巨人环境科技有限公司 | Method for treating paraquat pesticide wastewater |
| CN105366846B (en) * | 2015-09-11 | 2018-08-21 | 广东绿巨人环境科技有限公司 | The clever agricultural chemicals waste water processing method of hundred grass of one kind |
| CN106115726A (en) * | 2016-06-18 | 2016-11-16 | 上海应用技术学院 | A kind of preparation method of ferrum carbon modified mesoporous molecular sieve |
| CN106045147A (en) * | 2016-08-05 | 2016-10-26 | 山东明泰环保科技有限公司 | Organic waste water MT polyphase catalytic oxidation device |
| CN106957091A (en) * | 2017-03-03 | 2017-07-18 | 苏文灿 | A kind of processing method of organic industrial sewage |
| CN112755754A (en) * | 2021-01-04 | 2021-05-07 | 深圳市奇信集团股份有限公司 | Aldehyde-removing water-absorbing resin ball and preparation method thereof |
| CN113401979A (en) * | 2021-07-07 | 2021-09-17 | 湖南正海现代实验室设备有限公司 | Heterogeneous catalytic oxidation water treatment facilities |
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Application publication date: 20130306 |