CN102910757B - Treatment technique of waste water generated in production of o-nitrophenol - Google Patents
Treatment technique of waste water generated in production of o-nitrophenol Download PDFInfo
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- CN102910757B CN102910757B CN201210373446XA CN201210373446A CN102910757B CN 102910757 B CN102910757 B CN 102910757B CN 201210373446X A CN201210373446X A CN 201210373446XA CN 201210373446 A CN201210373446 A CN 201210373446A CN 102910757 B CN102910757 B CN 102910757B
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Abstract
The invention discloses treatment technique of waste water generated in production of o-nitrophenol. The treatment technique comprises the following steps: firstly, pretreating waste water, entering a resin adsorption column for adsorption, desorbing the resin by adopting NaOH solution after the resin adsorption is saturated, adding acid into high-concentration desorption solution for acidizing so as to recover o-nitrophenol, wherein a low-concentration desorption solution sleeve is used for desorption, distilling and purifying the recovered o-nitrophenol, conducting hydrogenation and catalysis to produce o-nitrophenol; carrying out ozone oxidation, neutralization and decoloration on the waste water after being subjected to adsorption treatment, thereby becoming qualified salt water. After the technique is adopted, organic pollution of the waste water to water environment is lightened, the resource utilization can be realized, and the treatment technique has great economic values and practical values in treating the waste water generated in production of o-nitrophenol.
Description
Technical field
The present invention relates to a kind of waste water treatment process, be specifically related to a kind of disposal and utilization of o-NP saliferous factory effluent.
Background technology
O-NP is a kind of important organic intermediate, is widely used in the industry such as dyestuff, medicine, also can be used as analytical reagent, can be used to manufacture oxine, chloro sulphur phenol S, Ortho-Aminophenol etc.
There are a lot of reports the treatment technology aspect of relevant o-NP factory effluent, such as iron carbon reduction+anaerobism+oxygen consumption, and extraction treatment method, active carbon adsorption, magnetic strength sodium hypochlorite oxidization, sulfonation matchmaker absorption method, resin adsorption method etc.Some only is confined to bibliographical information and laboratory experiment, and some working costs are too high.Resin adsorption method is processed this waste water effect and is better than additive method, and the method not only can reduce COD, can also reclaim o-NP, and the o-NP of recovery can directly return to production workshop section.The method has not only been administered waste water, and has improved the product yield of o-NP.
In recent years, adopt the example of resin adsorption method Phenol-Containing Wastewater Treatment more both at home and abroad, but the resinous type adopted differ greatly.For example, China Jiangsu chemical enterprise has just adopted the macroporous resin device to process the waste water that contains o-NP.Its waste water is mainly in the o-NP production process, to separate the waste water that acidified mother liquor produces, and generation is 5439.8t/a, in waste water, mainly contains part o-NP, sodium-chlor and hydrochloric acid, and COD is about 8000-10000mg/L.Above-mentioned waste water is processed through macroporous resin adsorption device, together with macroporous resin regeneration, washes, delivering to its company's sewage works processes, reached treatment effect preferably, but because its saltiness still is difficult to reach re-set target, treatment effect is not obvious.
Summary of the invention
The present inventor is for waste water in existing o-NP production process, particularly separate the waste water that acidified mother liquor produces, a kind of brand-new technique of utilizing resin to process is provided, alleviated the organic contamination of waste water to water surrounding, realize simultaneously the utilization of resources, in the processing of o-NP factory effluent, had great economic worth and practical value.
A kind of o-NP production wastewater treatment technique, concrete steps comprise:
(1) Wastewater Pretreatment: waste water enters the Waste Water Centralized pond lowers the temperature and sedimentation, reaches normal temperature, then enters the baffling tank, and to remove degreasing, after baffling, waste water enters the strainer filtration;
(2) pretreated waste water enters resin absorbing column absorption;
(3) resin after absorption in step (2) is saturated adopts the sodium hydroxide solution desorption;
(4) high concentration desorption liquid got off from step (3) desorption adopts hydrochloric acid soln to carry out acidifying and reclaims o-NP, and the light concentration desorption liquid cover is for desorption process;
(5) after the liquid after resin absorbing column absorption is through peroxidation, neutralization, except ammonia, decolouring, obtain sodium chloride brine.
Wherein, because this waste water is mainly the acid mother liquid in o-NP salt acidifying process, the pH value is about 2～3, and temperature is higher, contain some oils, can damage resin, therefore can not directly with resin, adsorb it, must carry out pre-treatment to it, namely described step (1).
The resin adopted in described step (2) is the XDA-1 resin, by market, directly buied, it is a kind of high-specific surface area macroporous adsorbent resin, p-nitrophenol class material has efficient adsorption selectivity, and the XDA-1 resin is the resin that a kind of antipollution is strong, suction phenol amount is large, desorption is not affected by salt easily.
Adsorption rate is 1～20BV/h in described step (2), best in this scope internal adsorption effect, with a collection of waste water ratio, if adsorption rate, lower than 1BV/h, can extend adsorption time, make the wastewater treatment overlong time, production cost increases, and can not meet industrial requirement; If higher than 20BV/h, the too fast meeting of adsorption rate makes absorption not exclusively, and residual o-NP in waste water, do not reach the expection purpose of wastewater treatment.
Desorption temperature is 30～100 ℃ in described step (3), owing in desorption process, producing sodium onitrophenol, if desorption temperature lower than 30 ℃, sodium onitrophenol crystallization meeting occluding device and pipeline; If higher than 100 ℃, higher to equipment and requirements for pipes, increased cost for wastewater treatment.
In described step (3), desorption rate is 1～20BV/h, if desorption rate is excessively slow, can extend desorption time, the wastewater treatment overlong time, and production cost increases, and can not meet need of production; If desorption rate is too fast, cause desorption not thorough, the o-NP rate of recovery is low, and can reduce the processing power of resin.
Sodium hydroxide solution in described step (3), using this as desorbing agent, this is because in actual production, need to reclaim sodium chloride brine, in order not bring other impurity into, thereby select NaOH solution as desorbing agent, after o-NP is reclaimed, in sodium chloride brine, do not contain other impurity, can be back to chlor-alkali production; If select other alkali lye, can introduce impurity, impurity need to be disposed and just sodium chloride brine can be obtained, be back to the production of chlor-alkali, can increase wastewater treatment step and processing cost like this.
In described step (3), the massfraction of sodium hydroxide solution is 1～10%, if the massfraction of sodium hydroxide solution is too low, can bring a large amount of water into to wastewater treatment, increased wastewater flow rate, reduced the concentration of recuperable sodium chloride brine, treatment effect is bad; If too high, local sodium onitrophenol excessive concentration, easily Crystallization Plugging equipment and pipeline in the time of can causing desorption.
So under such desorption conditions, the complete desorption of the o-NP of resin absorption gets off, make resin be able to reprocessing cycle and use, reduced production cost; The sodium chloride brine finally obtained, enter electrolyzer and produce caustic soda as electrolytic solution, usings this as the raw material of producing o-NP, thereby realize the harmless treatment of whole waste water, and realized the recycle of resource.
In described step (4), adopt hydrochloric acid soln to carry out acidifying, this is because in actual production, needs to reclaim sodium chloride brine, in order not bring other impurity into, thereby select hydrochloric acid soln to carry out acidifying, and reclaim in the sodium chloride brine obtained and do not contain other impurity like this, can be back to chlor-alkali production; If select other acid solutions, can introduce impurity, need to dispose impurity and just can obtain sodium chloride brine, thereby be back to the production of chlor-alkali, can increase wastewater treatment step and processing cost like this.
In described step (4), the massfraction of hydrochloric acid soln is 5%-35%, if the excessive concentration of hydrochloric acid soln, hydrochloric acid easily volatilizees, and cost improves; If concentration is too low, can in N-process, bring a large amount of water into, increased wastewater flow rate, and poor processing effect.
Described step (4) middle and high concentration desorption liquid refers to the solution that the sodium hydroxide massfraction is greater than 5%, and light concentration desorption liquid refers to the solution that the sodium hydroxide massfraction is less than 5%.In the high concentration desorption liquid like this step (3) desorption got off, sodium hydroxide reacts the sodium onitrophenol of generation near saturated with o-NP, thereby the hydrochloric acid soln that the employing massfraction is 5%-35% carries out acidifying, recovery obtains o-NP, again after distilation, but hydrogenation catalyst is for the production of Ortho-Aminophenol; In light concentration desorption liquid, contain unreacted sodium hydroxide solution completely, can continue to react with o-NP, so use when the light concentration desorption liquid cover is used for desorption, realized like this having reduced production cost by resource circulation utilization.
In described step (5) in oxidising process oxygenant used be a kind of in clorox, ozone, potassium permanganate, be preferably ozone.If, can there be free chlorine in the employing hypochlorite oxidation, needs could be by the sodium chloride brine reuse after blowing down and processing; If adopt potassium permanganate can produce solid impurity, need to increase step and the expense of processing solid waste; Why selecting ozone to make oxygenant, is because in oxidising process, can not produce other by products except water and sodium-chlor, introduces other impurity can for the waste water of handling well.
So adopt the o-NP in ozone oxidation waste water, in and waste water in acidic substance, remove the ammonia nitriding compound, and the processing of decolouring, do not produce other by products and become qualified sodium chloride brine, enter electrolyzer and produce caustic soda as electrolytic solution, using this as the raw material of producing o-NP, thereby realize the harmless treatment of whole waste water, and realized the recycle of resource.
The present invention at first to the o-NP factory effluent lower the temperature, sedimentation processes, reach normal temperature, then enter the baffling tank, remove oily substance in waste water, through pretreated waste water, enter the absorption of XDA-1 resin absorbing column, adsorption column adopts two post series connection absorption, when the one-level adsorption column adsorbs near after saturated, by valve, make original secondary pillar become the one-level pillar, with the 3rd pillar, change original main adsorption column, namely adsorbed saturated one-level adsorption column, do the secondary absorption post, multistage like this continuous adsorption, absorption is more complete; If it is saturated that the one-level adsorption column has adsorbed, stop absorption, carry out desorption manipulation, simultaneously the secondary absorption post becomes again the one-level adsorption column, and with the 3rd adsorption column, the i.e. adsorption column of desorption end, start secondary absorption, three posts like this recycle, but operate continuously reduces costs.
For protection of the environment, and cost-saving, form the recycle of resource, adopt NaOH solution to carry out desorption to resin, the content of the waste water total ammonia nitrogen after the gained desorption is processed is less than 4ppm, sodium chloride content is 12% left and right, through ozone oxidation o-NP wherein, in and waste water in acidic substance, remove the ammonia nitriding compound, and the processing of decolouring, can become qualified sodium chloride brine, enter electrolyzer and produce caustic soda as electrolytic solution, using this as the raw material of producing o-NP, thereby realize the harmless treatment of whole waste water, and realized the recycle of resource.
After adopting this treatment process, alleviate the organic contamination of waste water to water surrounding, realized simultaneously the recycle of resource, reduced production cost, in the processing of o-NP factory effluent, had great economic worth and practical value.
The accompanying drawing explanation
Fig. 1 is the schema of waste water treatment process of the present invention.
Embodiment
Embodiment 1
(1) Wastewater Pretreatment: waste water enters the Waste Water Centralized pond lowers the temperature and sedimentation, reaches normal temperature and then enters the baffling tank, and to remove degreasing, after baffling, waste water enters strainer, and preprocessing process finishes;
(2) by pretreated 20m
3Waste water enters the absorption of XDA-1 resin absorbing column, and adsorption column adopts Φ 1000 * 5200 specifications, in-built XDA-1 resin 5m
3, adsorption rate is 1BV/h;
(3) the saturated rear resin of absorption in step (2) being adopted to massfraction is that 10% sodium hydroxide solution is made desorbing agent, under 30 ℃ with the speed desorption of 1BV/h;
(4) it is that o-NP is reclaimed in 30% hydrochloric acid soln acidifying that the high concentration desorption liquid got off from step (3) desorption adds massfraction, and the light concentration desorption liquid cover, for desorption process, reclaims o-NP 50.1Kg altogether, and its rate of recovery is 83.5%;
(5) after the liquid after resin absorbing column absorption is through peroxidation, neutralization, except ammonia, decolouring, obtain sodium chloride brine, mass content is 11.48%.
Embodiment 2
(1) Wastewater Pretreatment: waste water enters the Waste Water Centralized pond lowers the temperature and sedimentation, reaches normal temperature and then enters the baffling tank, and to remove degreasing, after baffling, waste water enters strainer, and preprocessing process finishes;
(2) pretreated 20m
3Waste water enters the absorption of XDA-1 resin absorbing column, and adsorption column adopts Φ 1000 * 5200 specifications, in-built XDA-1 resin 5m
3, adsorption rate is 20BV/h;
(3) the saturated rear resin of absorption in step (2) is adopted 1% sodium hydroxide solution make desorbing agent, under 100 ℃ with the speed desorption of 20BV/h;
(4) it is that 20% hydrochloric acid soln acidifying is recovered to o-NP that the high concentration desorption liquid got off from step (3) desorption adds massfraction, and the light concentration desorption liquid cover, for desorption process, reclaims o-NP 49.9Kg altogether, and the rate of recovery is 83.2%;
(5) after the liquid after resin absorbing column absorption is through peroxidation, neutralization, except ammonia, decolouring, obtain sodium chloride brine, mass content is 11.49%.
Embodiment 3
(1) Wastewater Pretreatment: waste water enters the Waste Water Centralized pond lowers the temperature and sedimentation, reaches normal temperature and then enters the baffling tank, and to remove degreasing, after baffling, waste water enters strainer, and preprocessing process finishes;
(2) pretreated 20m
3Waste water enters the absorption of XDA-1 resin absorbing column, and adsorption column adopts Φ 1000 * 5200 specifications, in-built XDA-1 resin 5m
3, adsorption rate is 12BV/h;
(3) the saturated rear resin of absorption in step (2) being adopted to massfraction is that 7% sodium hydroxide solution is made desorbing agent, under 70 ℃ with the speed desorption of 15BV/h;
(4) it is that 5% hydrochloric acid soln acidifying is recovered to o-NP that the high concentration desorption liquid got off from step (3) desorption adds massfraction, and the light concentration desorption liquid cover, for desorption process, reclaims o-NP 51.8Kg altogether, and the rate of recovery is 86.3%;
(5) after the liquid after resin absorbing column absorption is through peroxidation, neutralization, except ammonia, decolouring, obtain sodium chloride brine, mass content is 12.00%.
Embodiment 4
(1) Wastewater Pretreatment: waste water enters the Waste Water Centralized pond lowers the temperature and sedimentation, reaches normal temperature, then enters the baffling tank, and to remove degreasing, after baffling, waste water enters strainer, and preprocessing process finishes;
(2) pretreated 20m
3Waste water enters the absorption of XDA-1 resin absorbing column, and adsorption column adopts Φ 1000 * 5200 specifications, in-built XDA-1 resin 5m
3, adsorption rate is 8BV/h;
(3) the saturated rear resin of absorption in step (2) being adopted to massfraction is that 4% sodium hydroxide solution is made desorbing agent, under 80 ℃ with the speed desorption of 10BV/h;
(4) it is that o-NP is reclaimed in 35% hydrochloric acid soln acidifying that the high concentration desorption liquid got off from step (3) desorption adds massfraction, and the light concentration desorption liquid cover, for desorption process, reclaims o-NP 59.3Kg altogether, and its rate of recovery is 98.8%;
(5) after the liquid after resin absorbing column absorption is through peroxidation, neutralization, except ammonia, decolouring, obtain sodium chloride brine, mass content is 12.03%.
From embodiment 1-4, can find out, the rate of recovery of o-NP is more than 83%, then after distilation, but hydrogenation catalyst is for the production of Ortho-Aminophenol; The sodium chloride brine obtained after the o-NP production wastewater treatment, mass content is in 12% left and right, can enter electrolyzer and produce caustic soda as electrolytic solution, using this as the raw material of producing o-NP, thereby realize the harmless treatment of whole waste water, and realized the recycle of resource, reduced production cost.
Comparative example
Utilize the sodium chloride brine after treatment process of the present invention is processed embodiment 1-4 gained to compare with processing front waste water, in Table 1:
Before table 1 o-NP production wastewater treatment and the result after processing relatively
As can be seen from the comparative examples, after utilizing the present invention to process the o-NP factory effluent, in the sodium chloride brine obtained, the mass content of total ammonia nitrogen is less than 4ppm, the mass content of o-NP is less than 1ppm, and the mass content of sodium-chlor is 12% left and right, can enter electrolyzer and produce caustic soda as electrolytic solution, using this as the raw material of producing o-NP, thereby realize the harmless treatment of whole waste water, and realized the recycle of resource, reduced production cost.
Claims (4)
1. o-NP production wastewater treatment technique, it is characterized in that: concrete steps comprise:
(1) Wastewater Pretreatment: waste water enters the Waste Water Centralized pond lowers the temperature and sedimentation, reaches normal temperature, then enters the baffling tank, and to remove degreasing, after baffling, waste water enters the strainer filtration;
(2) pretreated waste water enters resin absorbing column absorption;
(3) resin after absorption in step (2) is saturated adopts the sodium hydroxide solution desorption;
(4) high concentration desorption liquid got off from step (3) desorption adopts hydrochloric acid soln to carry out acidifying and reclaims o-NP, and the light concentration desorption liquid cover is for desorption process;
(5) after the liquid after resin absorbing column absorption is through peroxidation, neutralization, except ammonia, decolouring, obtain sodium chloride brine;
The resin adopted in described step (2) is the XDA-1 resin;
In described step (3), the massfraction of sodium hydroxide solution is 1%～10%;
Described step (4) middle and high concentration desorption liquid refers to the solution that the sodium hydroxide massfraction is greater than 5%, and light concentration desorption liquid refers to the solution that the sodium hydroxide massfraction is less than 5%;
In described step (4), the massfraction of hydrochloric acid soln is 5%-35%;
In the middle oxidising process of described step (5), oxygenant used is ozone.
2. o-NP production wastewater treatment technique according to claim 1 is characterized in that: in described step (2), adsorption rate is 1～20BV/h.
3. o-NP production wastewater treatment technique according to claim 1 is characterized in that: in described step (3), desorption temperature is 30～100 ℃.
4. o-NP production wastewater treatment technique according to claim 1 is characterized in that: in described step (3), desorption rate is 1～20BV/h.
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| CN104193071A (en) * | 2014-09-27 | 2014-12-10 | 安徽金禾实业股份有限公司 | Treating method of high-ammonia-nitrogen mother liquor wastewater in MCP (methyl cyclopentenolone) production |
| CN106630297A (en) * | 2017-01-18 | 2017-05-10 | 上海应用技术大学 | Wet-method catalytic oxidation treatment method of vanillin production wastewater |
| CN106865805B (en) * | 2017-03-31 | 2020-10-27 | 莱特莱德（北京）纯水设备技术股份有限公司 | Organic phenol waste water does not have useless discharging equipment |
| CN107129078A (en) * | 2017-04-28 | 2017-09-05 | 南京环保产业创新中心有限公司 | O-aminophenol wastewater treatment and method of resource |
| CN108002622A (en) * | 2017-11-16 | 2018-05-08 | 王小军 | A kind of method administered with remanufacture benzofuraxan waste liquid |
| CN108178364B (en) * | 2017-11-27 | 2021-11-16 | 上海化学工业区中法水务发展有限公司 | Method for treating organic matters in high-salinity industrial wastewater |
| CN108046454A (en) * | 2017-12-29 | 2018-05-18 | 南通波涛化工有限公司 | A kind of resin adsorption method pre-processes waster water process containing phenol |
| CN108129271A (en) * | 2018-01-09 | 2018-06-08 | 江苏振方生物化学有限公司 | A kind of method of the chloro- 3,5- dinitro-p-trifluorotoluenes waste water acidification recycling phenol of 4- |
| CN108793493A (en) * | 2018-06-22 | 2018-11-13 | 西安蓝深环保科技有限公司 | O-aminophenol recovery and treatment method in a kind of strong brine |
| CN109081494A (en) * | 2018-09-21 | 2018-12-25 | 宁夏大学 | The device of organic macromolecule in a kind of removal industrial wastewater |
| CN110980864A (en) * | 2019-12-25 | 2020-04-10 | 湖北鸿鑫化工有限公司 | Method for treating o-nitrophenol production wastewater |
| CN114291916A (en) * | 2021-12-31 | 2022-04-08 | 天富凯业(辽宁)新材料有限公司 | System and method for recycling o-aminophenol from o-aminophenol acidification wastewater |
| CN114772774B (en) * | 2022-02-21 | 2024-05-28 | 安徽东至广信农化有限公司 | Nitrochlorobenzene production wastewater treatment method |
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| CN100391922C (en) * | 2006-11-24 | 2008-06-04 | 王在军 | Pyrocatechin and hydroquinone production process |
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