CN107555641B - Pretreatment method of coking wastewater - Google Patents
Pretreatment method of coking wastewater Download PDFInfo
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Abstract
The invention provides a method for pretreating coking wastewater by a primary Fenton oxidation, secondary Fenton oxidation and coagulating sedimentation combined process. High concentration ofAfter the coking wastewater is treated by the method, long-chain and cyclic organic matters in the wastewater are effectively degraded, the biodegradability of the wastewater is greatly improved, and a good foundation is laid for subsequent biochemical treatment. In the pretreatment stage, the metallurgical pickling waste liquid is added into a Fenton oxidation reaction tank, so that the pickling waste liquid of a steel mill is recycled to the maximum extent, and waste acid resources and Fe in the pickling waste liquid are fully utilized2+The Fenton oxidation reaction is maintained by adding acid and ferrous iron catalyst instead of the traditional method, so that the operation cost of wastewater treatment is greatly saved, the purpose of waste control by waste is achieved, the policy guidance of developing circular economy advocated by the state is met, and the method has important practical significance for the sustainable development of the coking enterprises.
Description
Technical Field
The invention belongs to the technical field of industrial wastewater treatment, and particularly relates to a pretreatment method of coking wastewater.
Background
The coking wastewater is wastewater formed in the coal high-temperature dry distillation process, the coal gas purification process and the chemical product refining process, has complex components, high pollutant concentration, high chromaticity, high toxicity, very stable property and poor biodegradability, contains phenols, naphthalene, pyridine, quinoline and other heterocyclic rings and polycyclic aromatic compounds (PAHs) besides inorganic pollutants such as ammonia nitrogen, cyanogen, thiocyanate and the like, and is one of the components and complex industrial wastewater difficult to treat.
At present, the domestic secondary treatment process of pretreatment and biochemical treatment is generally adopted for treating the coking wastewater, but pollutants such as COD, ammonia nitrogen and the like in the wastewater after the conventional secondary biological treatment are difficult to discharge up to the standard, so that a new sewage discharge standard cannot be met, and the development of enterprises is severely restricted. And more complicated pretreatment and other methods are adopted to control the water quality entering the biochemical system before secondary biochemical treatment abroad, so as to prevent the concentration of toxic pollutants from being too high, and a three-level purification system is adopted after the biochemical treatment process. The three-stage treatment is a process flow consisting of various physicochemical methods including dephenolization, ammonia distillation, biological treatment, activated carbon adsorption and the like, and mainly including biological treatment. However, the operation and investment costs of the tertiary treatment process are high, if a proper pretreatment process can be screened out, the content of toxic factors entering a secondary biochemical system is greatly reduced after the pretreatment process is carried out, the biodegradability of the wastewater is improved, and the quality of the treated effluent is enhanced by adopting an efficient biochemical treatment system, so that the expensive tertiary treatment process is replaced, and the method has important practical significance for the sustainable development of enterprises.
In the production and processing processes of steel products, hydrochloric acid is often used for surface treatment to remove rusty materials on the surfaces of steel products, so that a large amount of pickling waste liquid is generated, wherein the pickling waste liquid contains a large amount of acid and ferrous ions, the discharge amount of the pickling waste liquid is increased along with the improvement of the yield and the quality of the steel products, and the discharge amount of the pickling waste liquid is about millions of cubic meters every year in China. At present, large-scale iron and steel enterprises generally adopt a sodium lurasite method to recover hydrochloric acid, but the method has high investment and operation cost and high energy consumption, and solid wastes such as acid-base mud and the like which are harmful to the environment are generated in the treatment process. Some small-sized steel enterprises have no condition for recycling acid waste liquid, and generally adopt an alkali-adding neutralization method for treatment and then discharge the acid waste liquid. A method for recycling the pickling waste liquid with low cost and high efficiency is found, so that the pickling waste liquid resource of a steel mill is utilized to the maximum extent, and the method is always an environmental protection problem faced by the steel mill at present and for a period of time in the future.
By searching for new patents, relevant patents and articles, such as patents, are retrieved "The patent of the treatment method of coking wastewater (CN101781067A) comprises the steps of enabling the coking wastewater to pass through an oil separation tank, a regulating tank, an iron-carbon-Fenton oxidation tank, an up-flow anaerobic sludge bed reactor, a hydrolysis multifunctional tank, an anoxic tank, a composite activated sludge tank and a secondary sedimentation tank, and then discharging effluent. The method needs more structures to be treated, has complex process, large occupied area and higher operation cost. The patent 'pretreatment method of coking wastewater' (CN 201010201824.7) discloses a pretreatment method of coking wastewater, which adopts internal electrolysis, Fenton oxidation and coagulating sedimentation processes in sequence in the pretreatment stage, lays a foundation for subsequent biochemical treatment after improving the biodegradability of wastewater, but concentrated sulfuric acid needs to be added in the internal electrolysis process to adjust the wastewater to be an acidic environment, and a large amount of Fe needs to be added in the Fenton oxidation process2+Catalyst and oxidant H2O2Resulting in high cost of wastewater treatment and unfavorable for practical engineering application. The patent "a method for pretreating coking wastewater by an electrochemical oxidation flocculation combined process" (CN 200710025657.3) discloses a method for pretreating coking wastewater by an electrochemical oxidation flocculation combined process, which comprises the following steps: the method comprises the steps of firstly adjusting the pH value of the wastewater, adding ferrous ions into the wastewater, and then enabling the wastewater to sequentially pass through a high-voltage pulse discharge oxidation region, a high-frequency pulse direct-current electrolytic oxidation region, a micro-bubble oxidation region, a coagulation reaction region and a precipitation region, wherein the high-voltage pulse and the high-frequency pulse are two strong oxidation modes with different mechanisms, and meanwhile, organic matters are degraded under the action of a liquid and solid dual catalyst, so that the removal effect is strong. However, the process has the defects of more complicated operation, aging of the catalyst, higher operation cost and the like. "iron filings/Coke/H2O2Experimental study on pretreatment of coking wastewater by the method "(Chen Fang Yan et al), the article discusses the use of iron filings/coke/H2O2The method treats the coking wastewater, and research results show that the pretreatment effect of the coking wastewater can be obviously improved and the reaction time can be shortened. Firstly, iron filings are sieved, soaked, pickled and washed, then the iron filings and the washed coke are put into a reactor, and after hydrogen peroxide is added, stirring reaction is carried out. Because the oxidation of the hydrogen peroxide has selectivity, the hydrogen peroxide is subjected to internal electrolysisThe process is carried out in a time and space, which causes the disadvantages of increased consumption of oxidant, incomplete oxidation process, higher operation cost, etc.
In conclusion, because the coking wastewater has complex and variable components and contains various long-chain and cyclic organic substances which are difficult to degrade, the biodegradability of the wastewater is poor, the existing pretreatment technology has unsatisfactory treatment effect, and some pretreatment technologies adopt advanced oxidation technology to pretreat the coking wastewater, the process flow is complex, the operation cost is high, and the method is not favorable for the amplification application of practical engineering. Aiming at the problems, a pretreatment method which has good treatment effect, simple process flow and reasonable equipment operation and investment cost is needed to be developed, and the method has important practical significance for the final standard-reaching discharge of coking wastewater and the sustainable development of coking enterprises.
Disclosure of Invention
The invention provides a pretreatment method of coking wastewater, which is characterized in that high-concentration coking wastewater is pretreated by a primary Fenton oxidation, secondary Fenton oxidation and coagulating sedimentation combined process according to the above steps, so that organic pollutants difficult to degrade are effectively removed, the biodegradability of the wastewater is greatly improved, and a foundation is laid for the final standard discharge of the coking wastewater.
A pretreatment method of coking wastewater is realized according to the following technical scheme:
a: first-stage Fenton oxidation treatment: injecting the coking wastewater in the regulating reservoir into a primary Fenton oxidation reaction tank by a pump, wherein the reaction tank is operated in an intermittent manner, adding pickling waste liquor under the condition of continuous stirring, and controlling the pH value of the wastewater in the oxidation tank to be 2.0-3.0; then adding hydrogen peroxide solution to make the concentration of hydrogen peroxide in the waste water reach 1000-1200 ppm. By means of H2O2In Fe2+Generates hydroxyl free radicals with high oxidation potential under the catalytic action of the catalyst, and selectively oxidizes organic matters remained in the wastewater. The oxidation reaction time is controlled to be 1-2h under the stirring state.
The main component of the pickling waste liquid is H+：1-5g/L，Fe2+：100-250g/L。
B: and (3) secondary Fenton oxidation treatment: effluent of first-stage Fenton oxidation reaction tankAnd entering a secondary Fenton oxidation reaction tank. The reaction tank still adopts intermittent operation due to Fe in the pickling waste liquid2+As a reaction catalyst, the catalyst can continuously play a role of catalysis, so that only H is added into the second-stage Fenton oxidation reaction tank2O2. Adding hydrogen peroxide solution under the condition of continuous stirring to make the concentration of hydrogen peroxide in the waste water reach 500-600ppm, and controlling the oxidation reaction time to be 0.5-1.5 h. Organic matters which are not degraded in the primary Fenton oxidation reaction tank are further degraded and removed.
C: coagulating sedimentation treatment: and the effluent of the secondary Fenton oxidation reaction tank flows into a coagulating sedimentation tank. 320-360ppm Ca (OH) is added into a coagulating sedimentation tank under the stirring state2Controlling the pH value of the wastewater to be 9-10 by using alkali liquor and 3-5ppm of PAM as a flocculating agent, aerating the wastewater while stirring to fully oxidize ferrous iron in the wastewater into ferric hydroxide easy to precipitate, stopping stirring and aerating the wastewater after the stirring time reaches 8-12min, and standing for precipitation for 20-30 min. And supernatant obtained after precipitation is the pretreated coking wastewater.
Through the synergistic effect of the processes, the destructive effect on the refractory organic matters is strengthened, the biodegradability of the wastewater is improved, and a foundation is laid for the final standard discharge of the subsequent coking wastewater.
The invention provides a method for pretreating coking wastewater by a primary Fenton oxidation, secondary Fenton oxidation and coagulating sedimentation combined process. After the high-concentration coking wastewater is treated by the method, long-chain and cyclic organic matters in the wastewater are effectively degraded, the biodegradability of the wastewater is greatly improved, and a good foundation is laid for subsequent biochemical treatment. In the pretreatment stage, the metallurgical pickling waste liquid is added into a Fenton oxidation reaction tank, so that the pickling waste liquid of a steel mill is recycled to the maximum extent, and waste acid resources and Fe in the pickling waste liquid are fully utilized2+The Fenton oxidation reaction is maintained by adding acid and ferrous iron catalyst instead of the traditional method, so that the operation cost of wastewater treatment is greatly saved, the purpose of waste control by waste is achieved, the policy guidance of developing circular economy advocated by the state is met, and the method has important practical significance for the sustainable development of the coking enterprises.
Drawings
FIG. 1 is a process flow diagram in the practice.
Detailed Description
The invention is further illustrated by the following examples.
Example 1
Injecting the coking wastewater in the regulating reservoir into a primary Fenton oxidation reaction tank by a pump, wherein the reaction tank is operated in an intermittent manner, adding pickling waste liquor under the condition of continuous stirring, and controlling the pH value of the wastewater in the oxidation tank to be 2.0; then adding hydrogen peroxide solution to make its concentration reach 1000 ppm. The oxidation reaction time is controlled to be 1h under the stirring state.
And the effluent of the primary Fenton oxidation reaction tank enters a secondary Fenton oxidation reaction tank. The reaction tank still adopts intermittent operation. Adding hydrogen peroxide solution under the condition of continuous stirring to make its concentration be up to 500ppm, and controlling oxidation reaction time to be 0.5 h.
And the effluent of the secondary Fenton oxidation reaction tank flows into a coagulating sedimentation tank. Adding 320ppm of Ca (OH) into a coagulating sedimentation tank under the stirring state2Controlling the pH value of the wastewater to be 9.0 by using alkali liquor and 3ppm of PAM as a flocculating agent, aerating the wastewater while stirring, stopping stirring and aerating the wastewater when the stirring time reaches 8min, and standing and precipitating for 20 min. And supernatant obtained after precipitation is the pretreated coking wastewater.
Example 2
Injecting the coking wastewater in the regulating reservoir into a primary Fenton oxidation reaction tank by a pump, wherein the reaction tank is operated in an intermittent manner, adding pickling waste liquor under the condition of continuous stirring, and controlling the pH value of the wastewater in the oxidation tank to be 2.5; then adding hydrogen peroxide solution to make its concentration reach 1100 ppm. The oxidation reaction time was controlled to 1.5h with stirring.
And the effluent of the primary Fenton oxidation reaction tank enters a secondary Fenton oxidation reaction tank. The reaction tank still adopts intermittent operation. Adding hydrogen peroxide solution under the condition of continuous stirring to make the concentration of the hydrogen peroxide solution reach 550ppm, and controlling the oxidation reaction time to be 1.0 h.
Discharge of secondary Fenton oxidation reaction tankThe water flows into a coagulating sedimentation tank. 340ppm of Ca (OH) is added into a coagulating sedimentation tank under the stirring state2Controlling the pH value of the wastewater to be 9.5 by using alkali liquor and 4ppm of PAM as a flocculating agent, aerating the wastewater while stirring, stopping stirring and aerating the wastewater when the stirring time reaches 10min, and standing and precipitating for 25 min. And supernatant obtained after precipitation is the pretreated coking wastewater.
Example 3
Injecting the coking wastewater in the regulating reservoir into a primary Fenton oxidation reaction tank by a pump, wherein the reaction tank is operated in an intermittent manner, adding pickling waste liquor under the condition of continuous stirring, and controlling the pH value of the wastewater in the oxidation tank to be 3.0; then adding hydrogen peroxide solution to make its concentration be up to 1200 ppm. The oxidation reaction time is controlled to be 2h under the stirring state.
And the effluent of the primary Fenton oxidation reaction tank enters a secondary Fenton oxidation reaction tank. The reaction tank still adopts intermittent operation. Adding hydrogen peroxide solution under the condition of continuous stirring to make its concentration be up to 600ppm, and controlling oxidation reaction time to be 1.5 h.
And the effluent of the secondary Fenton oxidation reaction tank flows into a coagulating sedimentation tank. Adding 360ppm of Ca (OH) into a coagulating sedimentation tank under the stirring state2Controlling the pH value of the wastewater to be 10.0 by using alkali liquor and 5ppm of flocculating agent PAM, aerating the wastewater while stirring, stopping stirring and aerating the wastewater when the stirring time reaches 12min, and standing and precipitating for 30 min. And supernatant obtained after precipitation is the pretreated coking wastewater.
The effect of each example on removing pollutants after the coking wastewater is pretreated by the process is shown in table 1.
Table 1 removal of contaminants by examples
As can be seen from the results in Table 1, the coking wastewater after the pretreatment has a COD removal rate of more than 62%, a total cyanogen removal rate of more than 91%, a volatile phenol removal rate of more than 93%, and BOD5The COD value is increased from the original value of less than 0.2 to the present value of more than 0.41, thereby strengthening the resistance to the degradation of organic mattersThe destruction of the substances greatly improves the biodegradability of the wastewater, the quality of the process effluent is stable, the water inlet condition of subsequent biochemical treatment is greatly improved, and a foundation is laid for the final standard discharge of the coking wastewater.
Claims (2)
1. A pretreatment method of coking wastewater is characterized by comprising the following steps:
a: first-stage Fenton oxidation treatment: injecting the coking wastewater in the regulating reservoir into a primary Fenton oxidation reaction tank by a pump, wherein the reaction tank is operated in an intermittent manner, adding pickling waste liquor under the condition of continuous stirring, and controlling the pH value of the wastewater in the oxidation tank to be 2.0-3.0; then adding hydrogen peroxide solution to make the concentration of hydrogen peroxide in the wastewater reach 1000-1200ppm, and controlling the oxidation reaction time to be 1-2h under the stirring state;
b: and (3) secondary Fenton oxidation treatment: the effluent of the primary Fenton oxidation reaction tank enters a secondary Fenton oxidation reaction tank; the reaction tank still adopts intermittent operation, hydrogen peroxide solution is added under the condition of continuous stirring, so that the concentration of hydrogen peroxide in the wastewater reaches 500-600ppm, and the oxidation reaction time is controlled to be 0.5-1.5 h;
c: coagulating sedimentation treatment: the effluent of the secondary Fenton oxidation reaction tank flows into a coagulating sedimentation tank, and 320-360ppm Ca (OH) is added into the coagulating sedimentation tank under the stirring state2Controlling the pH value of the wastewater to be 9-10 by using alkali liquor and 3-5ppm of PAM as a flocculating agent, aerating the wastewater while stirring to fully oxidize ferrous iron in the wastewater into ferric hydroxide easy to precipitate, stopping stirring and aerating the wastewater after the stirring time reaches 8-12min, standing and precipitating for 20-30min, and obtaining supernatant after precipitation, namely the pretreated coking wastewater.
2. The pretreatment method of coking wastewater according to claim 1, characterized in that: the main component of the pickling waste liquid is H+：1-5g/L，Fe2+：100-250g/L。
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103130379A (en) * | 2011-12-05 | 2013-06-05 | 鞍钢股份有限公司 | Processing method of coking steaming ammonia wastewater |
| CN103755097A (en) * | 2014-01-17 | 2014-04-30 | 上海交通大学 | Advanced oxidation-biological treatment device for non-biodegradable waste water |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103130379A (en) * | 2011-12-05 | 2013-06-05 | 鞍钢股份有限公司 | Processing method of coking steaming ammonia wastewater |
| CN103755097A (en) * | 2014-01-17 | 2014-04-30 | 上海交通大学 | Advanced oxidation-biological treatment device for non-biodegradable waste water |
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