CN102399040A - Process for comprehensively treating sulfur dye waste water - Google Patents
Process for comprehensively treating sulfur dye waste water Download PDFInfo
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- CN102399040A CN102399040A CN2010102775783A CN201010277578A CN102399040A CN 102399040 A CN102399040 A CN 102399040A CN 2010102775783 A CN2010102775783 A CN 2010102775783A CN 201010277578 A CN201010277578 A CN 201010277578A CN 102399040 A CN102399040 A CN 102399040A
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Abstract
The invention relates to a process for comprehensively treating sulfur dye waste water. The process of the invention uses a split-flow scheme which comprises that dye bath strong liquor with high concentration can be recycled and the comprehensive waste water with low concentration can be collected. The process of the invention comprises the following steps: acidifying the dye bath strong liquor with high concentration, blowing and recovering sodium sulfide, filtering and recovering the sulfur dye, wherein the recovery rate of the sodium sulfide and the sulfur dye can respectively reach more than 85% and 95%, collecting a filtrate into a waste water treatment system for treating; pretreating the comprehensive waste water with low concentration by an electrocoagulation process and discharging or carrying out biochemical treatment. Compared with the current art, the process of the invention has the advantages of high resource recovery rate, simple flow, less equipment, less land occupation, simple operation and maintenance and the like, and is suitable for recycling and treating the sulfur dye waste water.
Description
Technical field
The present invention relates to a kind of field of waste water treatment, more particularly relate to a kind of thioxine dyes dyeing waste water comprehensive management of technology and practical implementation technical scheme thereof.
Background technology
Thioxine dyes is a kind of water-insoluble dyestuff, can be used for dyeing keratin-fibers such as cotton, fiber crops, viscose glue.Its ME is simple, with low cost, fastness is high, uses extensively.Thioxine dyes is water insoluble, need use during dyeing sodium sulphite or other reductive agents with reducing dyes as solubility, fiber is had the avidity leuco compound, and then use oxygenant oxidation colour developing and recover insoluble state, it anchored on the fiber and accomplish dyeing.Thioxine dyes can produce great amount of wastewater in dyeing course, contain a large amount of salts, sulfide and dyestuff etc. in the waste water, has characteristics such as high salinity, high pH value, high sulfide content, high chroma and high COD, and is very big to ecotope harm, need handle.
At present, the end treatment mode is taked in the thioxine dyes wastewater treatment usually, and main technique is coagulating sedimentation+biochemistry.As precipitation agent and coagulating agent, the sulfide generation precipitin reaction in ferrous ion and the waste water generates the Iron sulfuret deposition to coagulating sedimentation with ferrous sulfate, superfluous simultaneously ferrous ion hydrolytic reactions; Generation ferrous hydroxide deposition; Have throwing out, the pH value is reduced, thioxine dyes is separated out.The coagulating sedimentation water outlet gets into biochemical treatment system, is born in COD with removal.This method treatment effect is good, but has following several problem: the first, because sulfides from wastewater content is higher, need add a large amount of ferrous sulfate, and not single working cost is higher, also produces a large amount of mud simultaneously, causes the sludge treatment disposal costs high; The second because with the thioxine dyes that is contained in the waste water and the sulfide deposition that mixes, sediment can only carry out treatment and disposal as refuse, and is not only costly, and significant wastage resource; The 3rd, because the ferrous sulfate dosage is very big, cause in the waste water sulfate radical content higher, follow-up anaerobic biological treatment is had bigger harm.
In order to solve the predicament of end treatment, people have carried out cleaner production and resource utilization research.Cleaner production mainly is in dyeing process, to adopt new method that thioxine dyes is reduced into leuco compound and the use of avoiding sulfide, has introduced a kind of method of reducing sulfur dyes by electrocatalysis like patent 200810120424.6.This method is that negative electrode, noble electrode are anode with the silver electrode, in catholyte, adds thioxine dyes, under dyestuff starting point concentration 1~500g/L condition, carry out electrolysis under 5~80 ℃ of conditions, thioxine dyes is reduced to the water-soluble leuco body dyes.This method can avoid the use of sulfide, stops discharge of wastewater basically, has tangible cleaner production advantage.But this dyeing process process and complex equipments, energy consumption are high, operating requirement is harsh, and technical maturity is limited, also can't realize industrial applications.Resource utilization mainly is that the useful cost in the thioxine dyes waste water is recycled, and has introduced a kind of method of utilizing thioxine dyes waste water to prepare black sulfide dye and Sulfothiorine like patent 200810022432.7.Its specific practice be with a part of thioxine dyes waste water heating back with 2, the 4-DNCB mix and regulate the pH value with alkali after carry out hydrolysis reaction; With other a part of thioxine dyes waste water mix with sodium sulphite and sulphur, stirring heating, carry out many vulcanization reactions; Then the hydrolysis reaction mixed solution is mixed with many vulcanization reactions mixed solution and carry out vulcanization reaction, reaction finishes the back bubbling air and carries out oxidizing reaction, obtains mixing mother liquor; Mix mother liquor through filtering the black sulfide dye particle, the black sulfide dye particle mixes through dry, grinding, assembly and obtains the commodity black sulfide dye; Mixing mother liquor after the filtration obtains Sulfothiorine through concentrated, decolouring, crystallization, oven dry and screening.This method can realize the recycling of useful component in the thioxine dyes waste water, and technical process is complicated, equipment is various but reclaim, thereby causes investment and running cost is high, the operational management difficulty is big, and difficulty is with practical value.
In sum; Though thioxine dyes wastewater treatment, cleaner production and method of resource can be realized discharged wastewater met the national standard and part composition resource utilization; And reduce subsequent technique and handle load; But the common flow process of these methods is complicated, needs a plurality of unit process equipment, and investment is high, high, the complex operation of working cost; And many processing condition are comparatively harsh, also might have side reaction, influence product yield.In order to address these problems, need a kind of technology of exploitation is simple, investment is low, the recovery is high thioxine dyes wastewater treatment and process for reclaiming.
Summary of the invention
The present invention is directed to the problem that thioxine dyes wastewater treatment and process for reclaiming exist and improve, invented that a kind of technology is simple, organic efficiency is high, working cost is low, safeguard simple integrated conduct method:
(1) thioxine dyes waste water is carried out dense rare shunting, its middle and high concentration dye bath dope carries out resource utilization, and can focus on the lower concentration comprehensive wastewater;
(2) carry out acidifying for high density dye bath waste liquid, blast rare gas element (like nitrogen) stirring reaction then and simultaneously sulfonium ion is carried out stripping, the hydrogen sulfide that stripping produces absorbs with alkali lye and reclaims Sodium Sulphide, and reaction mother liquor reclaims the thick product of thioxine dyes through filtering; Filtrating is adjusted to milk of lime and enters system after the pH value 6~9 and focus on;
(3) low concentration wastewater for rinse water and supernatant composition at first adopts electricity flocculation carrying out pre-treatment, to remove pollutents such as residue sulfonium ion, dyestuff; Putting the back in waste water after treatment can directly be arranged gets into the comprehensive wastewater treatment system or directly enters municipal sewage pipe network; Deposition gained sediment can carry out burning disposal.
The present invention has made important improvement to existing thioxine dyes waste water treatment process, it is characterized in that:
(1) at first in high density dye bath waste liquid, add sulfuric acid, regulate pH value to 2~3, feed rare gas element (like nitrogen) and carry out stirring reaction, stripping, the reaction times, the alkali lye of the stink damp body and function 5~20% of generation absorbed at 5~30min, reclaimed Sodium Sulphide;
(2) mother liquor adopts plate-and-frame filter press filtered and recycled thioxine dyes behind reaction, stripping; Filtrating adds milk of lime and regulates and enter Waste Water Treatment behind pH value to 6~9 and focus on;
(3) low concentration wastewaters such as resource utilization waste liquid and poaching wastewater at first carry out the homogeneous adjusting in equalizing tank, adopt electric flocculation process to carry out pre-treatment then, and electric flocculation process adopts the ferroelectric utmost point, and current density is 100~400A/m
2, the iron consumption is 50~100g/t water;
(4) electricity flocculation water outlet can be carried out further biochemical treatment or directly enter the cities and towns pipe network system;
(5) electric flocculation separation gained body refuse is disposed or burning disposal through the dehydration outward transport.
The present invention compares with existing technology has following significant advantage and benefit:
(1) adopt dense rare shunting resolution, high density dye bath waste liquid is carried out resource recycling, and the lower concentration comprehensive wastewater is carried out end treatment, this can effectively improve the resource organic efficiency and reduce the comprehensive wastewater treatment cost;
(2) high density dye bath waste liquid is adopted acid out, stripping process, can in single step reaction, realize the resource utilization of thioxine dyes and sulfide, wherein the thioxine dyes recovery can reach more than 95%, and the sulfide recovery can reach about 85%.Not only flow process is simple, equipment is few for this technology, investment is low, and easy and simple to handle, management difficulty is low, has stronger suitability.
(3) adopt electric flocculation process to carry out pre-treatment for the lower concentration comprehensive wastewater; Can effectively remove suspended solids, COD, colourity and sulfide etc. in the waste water; Wherein suspended solids is lower than 50mg/L, COD and is lower than that 300mg/L, colourity are lower than 30, sulfide is lower than 1mg/L, can directly enter the cities and towns pipe network system or further get into biochemical treatment system.Advantages such as this technology has fixed investment province, floor space is little, working cost is low, operation automation.
Description of drawings
Fig. 1 is a high density dye bath effluent resource process flow sheet proposed by the invention
1-sulfuric acid among the figure; 2-nitrogen; 3-Sodium Sulphide; The 4-reaction mother liquor; 5-filtrating; The 6-filter residue; The 7-thioxine dyes
Fig. 2 is a lower concentration comprehensive effluent disposal technology schema proposed by the invention
8-pump among the figure; The 9-slag
Embodiment
Below in conjunction with accompanying drawing and instance the present invention is further specified.
Thioxine dyes waste water is adopted the shunting resolution, high density dye bath waste liquid is adopted recycling recovery process, then adopt electric flocculation process to carry out pre-treatment the lower concentration comprehensive wastewater.Accompanying drawing 1 is a high density dye bath effluent resource process flow sheet.Can know by Fig. 1; At first the dye bath waste liquid is carried out acidifying with sulfuric acid; Feed the nitrogen stirring reaction then and sulfide is carried out stripping, the hydrogen sulfide of stripping gained absorbs with alkali lye and reclaims Sodium Sulphide, and mother liquor filters; Filter residue can be made with extra care and reclaim thioxine dyes, and filtrating can enter Waste Water Treatment and focus on.Accompanying drawing 2 is a lower concentration comprehensive effluent disposal technology schema.Can know by Fig. 2; The lower concentration comprehensive wastewater adopts electric flocculation process to carry out pre-treatment; To remove suspended solids, COD, colourity, sulfide and dyestuff etc., processed waste water can directly enter the cities and towns pipe network or further carry out biochemical treatment, and the slag that the electricity flocculation produces is transported outward disposal behind dehydrating combustion.
Embodiment: adopt SULPHUR BLACK CRUDE according to actual dyeing process configuration simulated wastewater; Wherein dye bath waste liquid Containing Sulfur Black 1%, sodium sulphite 2%, sodium-chlor 3%, lower concentration comprehensive wastewater COD600mg/L, 200 times of colourities, sulfide 20mg/L, specific conductivity are greater than 10mS/cm.The dye bath waste liquid is at first adopted sulfuric acid acidation to pH value about 3; Feed nitrogen then and carry out stirring reaction and stripping; The hydrogen sulfide that produces absorbs recovery Sodium Sulphide with sodium hydroxide; Reaction mother liquor carries out the filtered and recycled SULPHUR BLACK CRUDE, and the sulfide recovery can reach 85%, and the SULPHUR BLACK CRUDE recovery can reach more than 95%.Comprehensive wastewater adopts the electricity flocculation to handle, and handles back water outlet COD less than 300mg/L, and colourity is less than 20 times, and sulfide can enter the cities and towns pipe network or carry out biochemical treatment less than 1mg/L.
Institute of the present invention adopting process is applicable to any thioxine dyes dyeing water treatment, and is not limited to concrete application case.
Claims (8)
1. a thioxine dyes wastewater comprehensive treatment technology is characterized in that: waste water is carried out dense rare shunting, high density dye bath waste liquid is carried out resource utilization, and can focus on the lower concentration comprehensive wastewater.
2. the high density dye bath effluent resource technology of narrating according to claim 1; It is characterized in that: at first carry out acidifying with sulfuric acid; Blast rare gas element (like nitrogen) stirring reaction then and simultaneously sulfonium ion is carried out stripping; The hydrogen sulfide that stripping produces absorbs with alkali lye and reclaims Sodium Sulphide, and reaction mother liquor reclaims the thick product of thioxine dyes through filtering; Filtrating is adjusted to milk of lime and enters system after the pH value 6~9 and focus on.
3. the lower concentration comprehensive effluent disposal technology of narrating according to claim 2 is characterized in that: at first adopt electricity flocculation carrying out pre-treatment, to remove pollutents such as residue sulfonium ion, dyestuff; Putting the back in waste water after treatment can directly be arranged gets into the comprehensive wastewater treatment system or directly enters municipal sewage pipe network; Deposition gained sediment can carry out burning disposal.
4. the high density dye bath effluent resource technology of narrating according to claim 2; It is characterized in that: acidifying pH value is controlled at 2~3; Feed rare gas element (like nitrogen) and carry out stirring reaction, stripping; Reaction times, the alkali lye of the stink damp body and function 5~20% of generation absorbed at 5~30min, reclaimed Sodium Sulphide.
5. the high density dye bath effluent resource technology of narrating according to claim 2 is characterized in that: mother liquor adopts plate-and-frame filter press filtered and recycled thioxine dyes behind reaction, stripping; Filtrating adds milk of lime and regulates and enter Waste Water Treatment behind pH value to 6~9 and focus on.
6. the lower concentration comprehensive effluent disposal technology of narrating according to claim 3; It is characterized in that: at first in equalizing tank, carry out homogeneous and regulate; Adopt electric flocculation process to carry out pre-treatment then; The electricity flocculation process adopts the ferroelectric utmost point, and current density is 100~400A/m2, and the iron consumption is 50~100g/t water.
7. the lower concentration comprehensive effluent disposal technology of narrating according to claim 3 is characterized in that: electricity flocculation water outlet can be carried out further biochemical treatment or directly enter the cities and towns pipe network system.
8. the lower concentration comprehensive effluent disposal technology of narrating according to claim 3 is characterized in that: mix electric flocculation separation gained body refuse and dispose or burning disposal through the dehydration outward transport.
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Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
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CN103288238A (en) * | 2013-05-30 | 2013-09-11 | 浙江莱美纺织印染科技有限公司 | System for pure and impure printing and dyeing wastewater separation and wastewater recycling treatment |
CN103641227A (en) * | 2013-12-10 | 2014-03-19 | 杭州立佳环境服务有限公司 | Method for eliminating heavy metal in industrial sewage |
CN104071929A (en) * | 2014-06-20 | 2014-10-01 | 张家港格林台科环保设备有限公司 | Method for efficiently removing sulfide in water and special device for method |
CN104211270A (en) * | 2014-10-11 | 2014-12-17 | 江苏同禾药业有限公司 | Method for treating cyclization waste water in production process of lipoic acid |
CN105130099A (en) * | 2015-07-24 | 2015-12-09 | 武汉科技大学 | Method of treating vacuum potassium carbonate desulfurization waste liquid through acidic separation-out/oxidization process |
CN105174582A (en) * | 2015-09-15 | 2015-12-23 | 山东农业大学 | Resource treatment process of 1-amino anthraquinone sulfurization reduction wastewater |
CN106242186A (en) * | 2016-08-31 | 2016-12-21 | 浙江奇彩环境科技股份有限公司 | A kind of recycling processing method of sulphur black technique waste water |
CN109293148A (en) * | 2018-10-26 | 2019-02-01 | 浙江新安化工集团股份有限公司 | A kind of processing unit and its processing method of sulfur-bearing brine waste |
CN109322011A (en) * | 2018-09-05 | 2019-02-12 | 宜宾丝丽雅股份有限公司 | Scrap rubber water recoverying and utilizing method and system in a kind of production of viscose glue |
CN115072926A (en) * | 2022-07-22 | 2022-09-20 | 沈阳工大蓝金环保产业技术研究院有限公司 | Full-quantitative treatment method for pigment and dye intermediate wastewater |
CN115745262A (en) * | 2022-11-21 | 2023-03-07 | 中国科学院过程工程研究所 | Desulfurization device and method for sulfur-containing and salt-containing process water |
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Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
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CN103288238A (en) * | 2013-05-30 | 2013-09-11 | 浙江莱美纺织印染科技有限公司 | System for pure and impure printing and dyeing wastewater separation and wastewater recycling treatment |
CN103288238B (en) * | 2013-05-30 | 2014-10-08 | 浙江莱美纺织印染科技有限公司 | System for pure and impure printing and dyeing wastewater separation and wastewater recycling treatment |
CN103641227A (en) * | 2013-12-10 | 2014-03-19 | 杭州立佳环境服务有限公司 | Method for eliminating heavy metal in industrial sewage |
CN104071929A (en) * | 2014-06-20 | 2014-10-01 | 张家港格林台科环保设备有限公司 | Method for efficiently removing sulfide in water and special device for method |
CN104071929B (en) * | 2014-06-20 | 2015-11-25 | 张家港格林台科环保设备有限公司 | A kind of method and special purpose device thereof removing Sulfide in water |
CN104211270A (en) * | 2014-10-11 | 2014-12-17 | 江苏同禾药业有限公司 | Method for treating cyclization waste water in production process of lipoic acid |
CN105130099A (en) * | 2015-07-24 | 2015-12-09 | 武汉科技大学 | Method of treating vacuum potassium carbonate desulfurization waste liquid through acidic separation-out/oxidization process |
CN105174582A (en) * | 2015-09-15 | 2015-12-23 | 山东农业大学 | Resource treatment process of 1-amino anthraquinone sulfurization reduction wastewater |
CN106242186A (en) * | 2016-08-31 | 2016-12-21 | 浙江奇彩环境科技股份有限公司 | A kind of recycling processing method of sulphur black technique waste water |
CN106242186B (en) * | 2016-08-31 | 2019-04-30 | 浙江奇彩环境科技股份有限公司 | A kind of recycling processing method of sulphur black technique waste water |
CN109322011A (en) * | 2018-09-05 | 2019-02-12 | 宜宾丝丽雅股份有限公司 | Scrap rubber water recoverying and utilizing method and system in a kind of production of viscose glue |
CN109322011B (en) * | 2018-09-05 | 2021-03-23 | 宜宾丝丽雅股份有限公司 | Method and system for recycling waste glue water in viscose production |
CN109293148A (en) * | 2018-10-26 | 2019-02-01 | 浙江新安化工集团股份有限公司 | A kind of processing unit and its processing method of sulfur-bearing brine waste |
CN115072926A (en) * | 2022-07-22 | 2022-09-20 | 沈阳工大蓝金环保产业技术研究院有限公司 | Full-quantitative treatment method for pigment and dye intermediate wastewater |
CN115745262A (en) * | 2022-11-21 | 2023-03-07 | 中国科学院过程工程研究所 | Desulfurization device and method for sulfur-containing and salt-containing process water |
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