CN101200336B - Process for zero-discharge treatment of o-phenylenediamine sodium sulfide reduction wastewater - Google Patents
Process for zero-discharge treatment of o-phenylenediamine sodium sulfide reduction wastewater Download PDFInfo
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- CN101200336B CN101200336B CN2007101914560A CN200710191456A CN101200336B CN 101200336 B CN101200336 B CN 101200336B CN 2007101914560 A CN2007101914560 A CN 2007101914560A CN 200710191456 A CN200710191456 A CN 200710191456A CN 101200336 B CN101200336 B CN 101200336B
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- waste water
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- phenylenediamine
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Abstract
The invention relates to a zero-emission treatment process of O-phenylenediamine sodium sulfide reduction wastewater, which adopts the following steps in sequence: wastewater is filtered; O-phenylenediamine in the wastewater is absorbed and extracted by resin; the remained wastewater is vaporized and extracted to remove sodium chlorine; the wastewater that sodium chlorine is removed is filtered and crystallized to extract the sodium thiosulfate; the remained wastewater is concentrated to obtain sodium sulfite mixture. The invention can treat O-phenylenediamine sodium sulfide reduction wastewater with zero emission, so as to solve environmental pollution of wastewater thoroughly, thereby having obvious environmental benefit; simultaneously the wastewater is treated by the means of resource utilization, organic chemical product- O-phenylenediamine and inorganic product- sodium thiosulfate and sodium thiosulfate mixture are extracted from the wastewater; full process is a cleaning treatment process, not only secondary pollution is not generated but also energy is utilized circularly during process; the invention has small investment, simple process and practicality, and is applicable for popularization and utilization in the industry.
Description
Technical field
The present invention relates to the purification treatment technology of wastewater from chemical industry, particularly a kind of process for zero-discharge treatment of o-phenylenediamine sodium sulfide reduction wastewater.
Background technology
Domestic and international market Chemicals-O-Phenylene Diamine more salable mostly adopts the sodium sulfide reducing method to obtain.In the production process of O-Phenylene Diamine, can produce a certain amount of high density inevitably, certain toxic wastewater from chemical industry is arranged, directly discharge as not carrying out purifying treatment, then can cause serious environmental to pollute.At present, have producer to use o-phenylenediamine sodium sulfide reduction wastewater as mother liquor, Sulfothiorine is produced in regeneration, to reclaim useful component in the waste water, comes the treatment process of pollution abatement.But needing to add sulphur in the process of producing the Sulfothiorine product, this treatment process carry out oxidizing reaction, and for satisfying its processing condition, power consumption, coal consumption height, a large amount of obnoxious flavoures that produced in the reaction and waste residue, waste water have caused secondary pollution again.The applicant has proposed " a kind of method of purifying treatment o-phenylenediamine sodium sulfide reduction wastewater " (application number 200610041069.4) on July 20th, 2007 to State Intellectual Property Office, the processing step of this method is at first to adopt vacuum-evaporation mother liquor water (waste water), remove the contained sodium-chlor of mother liquor water, the vacuum concentration mother liquor water of desalination then, obtain material one S-WAT mixture at last.This method has solved the severe contamination problem that O-Phenylene Diamine produced of producing substantially, realized resource utilization production, under the situation of not adding other chemical material, the S-WAT mixture of producing is again the requisite raw material of paper industry with sulphite manufactured paper pulp, the method that the investment of entire treatment method is little, energy consumption is low, its regulation effect obviously is better than purifying treatment in the past.Although above-mentioned patent application project is confirmed certain a lot of beneficial effect that produced in practice, but, this method also exists some to improve part not to the utmost, as: the O-Phenylene Diamine that also exists content about 1% in (1) reducing waste water is not handled separately, these O-Phenylene Diamines are deposited in the S-WAT mixture as impurity at last, and also there is potentially contaminated in environment;
(2) manufacturing enterprise of some product O-Phenylene Diamines is also improving former technology now, and the consumption that wherein is expected Sodium Sulphide reduces to some extent, and the composition of reducing waste water is followed change has been taken place like this, so the method for purifying waste water processing also must change thereupon.
Summary of the invention
The present invention is directed to above-mentioned existing problems, a kind of process for zero-discharge treatment of o-phenylenediamine sodium sulfide reduction wastewater has been proposed, purpose is the variation according to the one-tenth branch generation of sodium sulfide reducing waste water, method row improvement again to existing purifying treatment o-phenylenediamine sodium sulfide reduction wastewater is handled o-phenylenediamine sodium sulfide reduction wastewater and is reached zero release.
Technical solution of the present invention
Thinking of the present invention is the effective constituent that makes full use of in the o-phenylenediamine sodium sulfide reduction wastewater, according to resin absorption principle and other chemical principle, takes following processing step to finish whole wastewater treatment process, and obtains organic and inorganic chemical product simultaneously.
Main technique steps in sequence of the present invention is:
(1) filtered wastewater;
(2) with the O-Phenylene Diamine in the resin absorption extraction waste water;
(3) the evaporation said extracted is crossed the residue waste water of O-Phenylene Diamine;
(4) remove sodium-chlor in the waste water;
(5) filter the above-mentioned waste water that has removed sodium-chlor;
(6) Sulfothiorine in the waste water is extracted in crystallization;
(7) concentrate residue waste water, finally obtain the S-WAT mixture.
Beneficial effect of the present invention
(1) treatment of o-phenylenediamine sodium sulfide reduction wastewater of the present invention has reached zero release, has thoroughly effected a radical cure the problem of environmental pollution of this type of waste water, has significant environmental benefit.
(2) handled o-phenylenediamine sodium sulfide reduction wastewater to resource utilization of the present invention, in waste water, extracted organic chemical industry's product-O-Phenylene Diamine, inorganic chemical product-Sulfothiorine, and S-WAT mixture;
(3) full technological process of the present invention is the treating processes that cleans, and not only non-secondary pollution produces, and in the technological process also recycle the energy;
(4) to invest little, technology simple and practical in the present invention, is suitable for utilization and extention in industry.
Description of drawings
Accompanying drawing 1 is the FB(flow block) of the whole technology of the present invention.
Accompanying drawing 2 extracts the process flow diagram of the O-Phenylene Diamine in the waste water with resin absorption for the present invention;
Accompanying drawing 3 is for removing the process flow diagram of the sodium-chlor in the waste water in the technology of the present invention;
Accompanying drawing 4 is for extracting the process flow diagram of the Sulfothiorine in the waste water in the technology of the present invention;
Accompanying drawing 5 is for obtaining the process flow diagram of S-WAT mixture from waste water in the technology of the present invention;
Embodiment
The basic chemical substance composition (by weight percentage) that the present invention will handle waste water is:
O-Phenylene Diamine (C
6H
8N
2) 0.8-1.2% sodium sulphite (Na
2S) 1.15-2.25%
Sodium hydroxide (NaOH) 2.4-3.6% Sulfothiorine (Na
2S
2O
3) 17.5-20%;
Other organism of sodium-chlor (NaCl) 8%-10% 0.8%-1.4%
Below in conjunction with process flow diagram, sketch this process implementing process:
(1) filtered wastewater.Adopt pressure filter, as water-insoluble and other impurity in plate-and-frame filter press, the removal waste water, the waste water after the filtration is positioned among the Chu Chi (jar).
(2) resin absorption is extracted the O-Phenylene Diamine in the waste water.According to assay, have about 1% O-Phenylene Diamine in the waste water, it be cause that waste water is poisonous, color and luster dark, one of the major ingredient of serious pollution.The technical process that resin absorption is extracted the O-Phenylene Diamine in the waste water is: adopt the O-Phenylene Diamine in the resin absorption waste water, use organic solvent desorb O-Phenylene Diamine molecule again, solvent is reclaimed in evaporation, the O-Phenylene Diamine crystallization, and solid-liquid separation can extract the O-Phenylene Diamine in the waste water.
The concrete operations step of this operation stage:
(1) resin absorption.To store up waste water after filtering in the pond (jar), pump in the elevated dosing vessel (jar) of resin absorption post top, the resin model is LXA-5 or for LXA-5B or be LXA-10B.During absorption, control speed and the adsorptive capacity of every batch of waste water by the resin absorption bed.Rate of adsorption generally is controlled at and at the uniform velocity descends 2BV/ hour (BV is the resin absorption bed volume), and general every batch of waste water adsorptive capacity is advisable with 8-10BV; Adsorptive capacity is to adopt qualitative method of controlling, observes the color of absorption back waste water, and waste water is as clear as crystal little yellow, resin absorption unsaturation still is described, can continues to inject waste water absorption, in a single day rubescent, deepening appears in waste water, illustrate that resin absorption is saturated, then stop to pass through waste water.The content of the O-Phenylene Diamine in the waste water of absorption back has been reduced to below 0.1%;
(2) O-Phenylene Diamine in the organic solvent desorb resin absorption post.The selected organic solvent of the present invention is the uniform mixing liquid of dehydrated alcohol and 1,2 ethylene dichloride, and the ratio of both volumes is 2: 1.This mixed organic solvents of 2BV amount is at the uniform velocity passed through the resin absorption bed from header tank (jar) with 1BV/ hour speed, the organic solvent that contains O-Phenylene Diamine after the collection desorb, go out to remain in organic solvent in resin bed and the resin duct with evaporation of vapours again, and be that condensing works recycles, subsequently again with the clear water of 2BV volume speed flushing adsorption column, and collect wash-down water to joining the reuse of alkali workshop with 3-4BV/ hour.
Waste water carries out resin absorption in batches, and repeats the operation process of above-mentioned (1), (2).
(3) recovery organic solvent, Crystallization Separation are obtained O-Phenylene Diamine.The organic solvent that contains O-Phenylene Diamine that above-mentioned collection is obtained, pump in the reactor that has condensing works, the surplus vapour that utilizes the production plant autoclave to produce evaporates, vaporization temperature is controlled between 85 ℃-90 ℃, the steam state solvent reclaims by condensing works, stops evaporation when this solvent of collecting reaches the 70-80% of the preceding solvent volume of evaporation.When the solution temperature that contains O-Phenylene Diamine in the reactor is reduced to 45 ℃-50 ℃, put into crystallizer tank lower the temperature naturally, along with decrease of temperature, when temperature decline reaches 28-30 ℃, a large amount of O-Phenylene Diamine crystal are separated out, through solid-liquid separation, its solid is that crystal perfection, color and luster are pure, and component content is up to 90% O-Phenylene Diamine.After surplus liquid after all previous repetition of above process, the separation is concentrated, can also carry out revaporization and extract the O-Phenylene Diamine that component content is 50-60%.And the organic solvent that is recovered to can be reused in recirculation.
This operation stage, the total extraction yield that extracts O-Phenylene Diamine in the waste water can reach between the 95%-98%.
(3) remove sodium-chlor in the waste water.The waste water that resin absorption was extracted O-Phenylene Diamine is inserted in the vaporizer with vacuum condensing unit and is evaporated, (the best is 51 degree Beaume) stops evaporation when waste strength is evaporated to the 50-55 degree Beaume, waste water after will evaporating while hot is placed into settling bath, and sodium-chlor is separated out naturally and is deposited at the bottom of the pond; In the evaporative process, the steam condensate of collecting (this water of condensation water white transparency, COD value are below 300mg/L) can be sent to joins the use of alkali workshop.
(4) extract Sulfothiorine.Get above-mentioned remove behind the sodium-chlor and the waste water after pressure filter filters is squeezed in the crystallizer tank, stir cooling, when wastewater temperature is reduced to 20-25 ℃, a large amount of thiosulfuric acid sodium crystals are separated out, carry out solid-liquid separation with whizzer, obtain to be little yellow, its component content at the Sulfothiorine that has 5 crystal water more than 82%.Can also be as needs to above-mentioned first time of crystalline Na
2S
2O
3.5H
2The O steam dissolving of heating again, and the adding powdered active carbon decolours, press filtration (filter residue can enter boiler and burn), the crystallization once more under 46 ℃ of-48 ℃ of temperature of the solution of the Sulfothiorine after the decolouring, that solid-liquid separation obtains is water white, component content reaches 98% the highly purified Sulfothiorine product that contains 5 crystal water.And the parting liquid after the solid-liquid separation (promptly remaining waste water) is concentrated and is entered following operation.
(5) waste water obtains the S-WAT mixture at last.
The chemical equation of this process section institute foundation is:
3Na
2S
2O
3+ 6NaOH=2Na
2S+4Na
2SO
3+ 3H
2The Sulfothiorine that the last waste water of O after because of said extracted Sulfothiorine is also retained sodium sulphite, sodium hydroxide and do not had to have extracted.This process section needs to carry out proportioning according to the required amount of the reaction generation of above-mentioned chemical equation, adds a certain amount of sodium hydroxide and satisfies reaction needed.Through practice, the amount that adds sodium hydroxide is the 3%-5% of last waste water weight.The chemical reaction of this process section carries out in the waste water concentration process, thickening temperature reaches between 140 ℃ ± 5 ℃ and stops to concentrate, behind the crystallisation by cooling, the block solid substance of gained sorrel, promptly based on S-WAT, also comprise the mixture of sodium sulphite, Sulfothiorine.The degree of component of mixture is: S-WAT 40-50%, sodium sulphite 25%-30%, Sulfothiorine 10-15%, water about 15%.The content of this mixture meets the content requirement of paper industry with the required industrial chemicals of sulphite manufactured paper pulp fully.
To sum up, processing step of the present invention vulcanizes sulphur alkali reducing waste water with O-Phenylene Diamine and carries out recycling treatment, has disposablely reached zero release, and active effect has been played in environment protection, has reached the expection goal of the invention.
Claims (6)
1. process for zero-discharge treatment of o-phenylenediamine sodium sulfide reduction wastewater, the operation stage that comprise filtered wastewater, evaporate the sodium-chlor that removes in the waste water, concentrated waste water finally obtains the S-WAT mixture, it is characterized in that: it behind filtered wastewater, before evaporation removes the operation stage of the sodium-chlor in the waste water, also is provided with the operation stage that extracts the O-Phenylene Diamine in the waste water with resin absorption described; And after evaporation removes sodium-chlor in the waste water, concentrate before waste water finally obtains the S-WAT mixture, also be provided with the operation stage that extracts the Sulfothiorine in the waste water; The described operation stage that extracts Sulfothiorine from waste water is the waste water that will remove behind the sodium-chlor, after filtering, pressure filter enters crystallizer tank, stir cooling, when wastewater temperature is reduced to 20-25 ℃, after treating that a large amount of thiosulfuric acid sodium crystals is separated out, carry out solid-liquid separation, obtain and be the flaxen Sulfothiorine that has 5 crystal water; The described complete process of extracting O-Phenylene Diamine from waste water is with the O-Phenylene Diamine in the resin absorption waste water, reclaims solvent with organic solvent desorb O-Phenylene Diamine molecule, evaporation again, the O-Phenylene Diamine crystallization promptly extracts O-Phenylene Diamine in organic solvent, through solid-liquid separation; Described organic solvent is the uniform mixing liquid of dehydrated alcohol and 1,2 ethylene dichloride, and the ratio of both volumes is 2: 1.
2. a kind of process for zero-discharge treatment of o-phenylenediamine sodium sulfide reduction wastewater according to claim 1, it is characterized in that: described evaporation is reclaimed the vaporization temperature of solvent between 85 ℃-90 ℃, condensing works reclaims the steam state solvent, when reaching the 70-80% of the preceding solvent volume of evaporation, the solvent of collecting stops evaporation, when the solution temperature that contains O-Phenylene Diamine in the reactor is reduced to 45 ℃-50 ℃, put into that crystallizer tank is lowered the temperature naturally, when the decline temperature reaches 28-30 ℃, the crystal of O-Phenylene Diamine is separated out, through solid-liquid separation, obtain O-Phenylene Diamine.
3. a kind of process for zero-discharge treatment of o-phenylenediamine sodium sulfide reduction wastewater according to claim 1, it is characterized in that: described evaporation removes the sodium-chlor in the waste water, be to stop evaporation when making its evaporative concn reach the 50-55 degree Beaume, waste water after will evaporating while hot is placed into settling bath, and sodium-chlor is separated out naturally and is deposited at the bottom of the pond.
4. a kind of process for zero-discharge treatment of o-phenylenediamine sodium sulfide reduction wastewater according to claim 1, it is characterized in that: describedly be the flaxen Sulfothiorine that has 5 crystal water, again through the steam dissolving of heating, add activated carbon decolorizing, press filtration, the crystallization once more under 46 ℃-48 ℃ temperature of the solution of the Sulfothiorine after the decolouring, solid-liquid separation obtain the Sulfothiorine that white high purity contains 5 crystal water.
5. a kind of process for zero-discharge treatment of o-phenylenediamine sodium sulfide reduction wastewater according to claim 1, it is characterized in that: described concentrated waste water finally obtains the operation stage of S-WAT mixture, be in the last waste water after extracting Sulfothiorine, add the sodium hydroxide that needs last Sulfothiorine reaction in satisfied and the waste water.
6. a kind of process for zero-discharge treatment of o-phenylenediamine sodium sulfide reduction wastewater according to claim 5, it is characterized in that: the chemical reaction of described Sulfothiorine and sodium hydroxide carries out in last waste water concentration process, thickening temperature remains between 140 ℃-150 ℃, and the amount of sodium hydroxide of adding is the 3%-5% of last waste water weight.
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Families Citing this family (10)
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|---|---|---|---|---|
| CN101913625A (en) * | 2010-08-03 | 2010-12-15 | 王嘉兴 | Method for preparing caustic soda, calcium carbonate, sodium thiosulfide and sodium iodide from sodium sulphide waste slag |
| CN103274538A (en) * | 2013-06-14 | 2013-09-04 | 陕西蓝深特种树脂有限公司 | System and method for recovering and treating p-phenylenediamine industrial wastewater |
| CN104086440A (en) * | 2014-06-10 | 2014-10-08 | 安徽华润涂料有限公司 | Technology for processing mother liquor of o-phenylenediamine |
| CN104860460A (en) * | 2014-12-05 | 2015-08-26 | 浙江龙盛集团股份有限公司 | Processing device for aniline intermediate production waste water |
| CN105001097A (en) * | 2015-06-11 | 2015-10-28 | 安徽东至广信农化有限公司 | O-phenylenediamine mother solution deaminizing and ammonia gas removal method |
| CN106380034A (en) * | 2015-07-28 | 2017-02-08 | 江苏吉华化工有限公司 | H-acid production wastewater treatment method |
| CN106316863A (en) * | 2016-08-13 | 2017-01-11 | 安徽东至广信农化有限公司 | Efficient o-phenylenediamine recovery method |
| CN107867776B (en) * | 2017-11-08 | 2021-03-02 | 江苏易简环保科技有限公司 | Method and process for recycling pesticide wastewater |
| CN112919609A (en) * | 2021-03-04 | 2021-06-08 | 沈阳大学 | Method for synergistically degrading azo dye by desulfurization slag through ultrasonic-ultraviolet-magnesium method |
| CN114715855A (en) * | 2022-01-17 | 2022-07-08 | 南方创业（天津）科技发展有限公司 | Method for extracting sodium thiosulfate pentahydrate by using alkaline residue wastewater |
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