阅读说明：本技术 一种利用含铁废酸液废水提高铁碳微电解反应效率的方法 (Method for improving iron-carbon micro-electrolysis reaction efficiency by using iron-containing waste acid liquor wastewater ) 是由 张炜铭 高亚娟 单超 汪林 唐凯 于 2020-04-23 设计创作，主要内容包括：本发明提供了一种利用含铁废酸液废水提高铁碳微电解反应效率的方法,属于废水处理与废酸资源化领域。所述方法在使用铁碳微电解反应去除废水中难降解有机物的过程中,在所述铁碳微电解反应前,反应中加入含Fe<Sup>2+</Sup>的废酸液废水,所述的含铁废酸液废水中还含有贵重金属元素。本发明的方法不仅利用含铁废酸液中的酸性体系调节铁碳微电解反应体系的pH环境,还利用酸液中大量的Fe<Sup>2+</Sup>具有的电子转移的作用,抑制作为填料的铁单质表面的氧化,防止铁碳填料上致密氧化层的形成,防止钝化,由此提高铁碳微电解的反应效率；同时利用贵重金属的催化作用显著降低有机物断链的活化能,显著提高铁碳微电解的反应效率。(Hair brushThe invention provides a method for improving iron-carbon micro-electrolysis reaction efficiency by using iron-containing waste acid liquor wastewater, belonging to the field of wastewater treatment and waste acid recycling. In the method, in the process of removing the organic matters difficult to degrade in the wastewater by using the iron-carbon micro-electrolysis reaction, Fe is added in the reaction before the iron-carbon micro-electrolysis reaction 2+ The waste acid liquid containing iron also contains precious metal elements. The method not only utilizes the acidic system in the waste acid solution containing iron to adjust the pH environment of the iron-carbon micro-electrolysis reaction system, but also utilizes a large amount of Fe in the acid solution 2+ The iron-carbon micro-electrolysis catalyst has the function of electron transfer, inhibits the oxidation of the surface of the iron simple substance serving as the filler, prevents the formation of a compact oxide layer on the iron-carbon filler, and prevents passivation, thereby improving the reaction efficiency of the iron-carbon micro-electrolysis; meanwhile, the catalytic action of the noble metal is utilized to obviously reduce the activation energy of chain scission of organic matters and obviously improve the reaction efficiency of iron-carbon micro-electrolysis.)

1. A method for improving iron-carbon micro-electrolysis reaction efficiency by using iron-containing waste acid liquor wastewater is characterized by comprising the following steps: in the method, Fe-containing is added before and/or during the iron-carbon micro-electrolysis reaction in the process of removing the organic matters difficult to degrade in the organic wastewater by using the iron-carbon micro-electrolysis reaction²⁺The iron-containing waste acid liquor wastewater also contains precious metal elements.

2. The method for improving the efficiency of iron-carbon micro-electrolysis reaction by using the iron-containing waste acid liquor wastewater as claimed in claim 1, wherein the method comprises the following steps: the iron-containing waste acid liquor wastewater comprises any one or combination of pickling waste liquor in the steel industry, pickling waste liquor in the electroplating industry and pickling liquor in the coal ash-to-aluminum oxide industry.

3. The method for improving the efficiency of iron-carbon micro-electrolysis reaction by using the iron-containing waste acid liquor wastewater as claimed in claim 1 or 2, wherein the method comprises the following steps: when the iron-containing waste acid liquid wastewater is added before the iron-carbon micro-electrolysis reaction, when the pH value of the organic wastewater is less than or equal to 2, adjusting the pH value of inlet water to 2-4 by using alkali liquor, and then adding the iron-containing waste acid liquid wastewater; when the pH value of the organic wastewater is more than 2 and less than 4, directly adding the iron-containing waste acid liquid wastewater; when the pH value of the organic wastewater is more than or equal to 4, directly adjusting the pH value of the organic wastewater to 2-4 by using the iron-containing waste acid liquor wastewater, and/or adjusting the pH value of the organic wastewater to 2-4 by using the iron-containing waste acid liquor wastewater and industrial strong acid in a synergistic manner.

4. The method for improving the efficiency of iron-carbon micro-electrolysis reaction by using the iron-containing waste acid liquor wastewater as claimed in claim 3, wherein the method comprises the following steps: the method specifically comprises the steps of flocculation and precipitation after the iron-carbon micro-electrolysis reaction: and (3) performing flocculation precipitation on the effluent after the iron-carbon micro-electrolysis reaction, and detecting the concentration of organic matters in the wastewater.

5. The method for improving the efficiency of iron-carbon micro-electrolysis reaction by using the iron-containing waste acid liquor wastewater as claimed in claim 4, wherein the method comprises the following steps: the method specifically comprises a Fenton oxidation treatment step, wherein effluent after the iron-carbon micro-electrolysis reaction enters a Fenton oxidation reaction unit for treatment, effluent after the Fenton oxidation reaction is subjected to flocculation precipitation, and the effluent is used for detecting the concentration of organic matters in the wastewater.

6. The method for improving the efficiency of iron-carbon micro-electrolysis reaction by using the iron-containing waste acid liquor wastewater as claimed in claim 1 or 2, wherein the method comprises the following steps: the organic wastewater comprises any one or combination of nitrobenzene production wastewater, medical wastewater, printing and dyeing wastewater and petrochemical comprehensive wastewater.

7. The method for improving the efficiency of iron-carbon micro-electrolysis reaction by using the iron-containing waste acid liquor wastewater as claimed in claim 4 or 5, wherein the method comprises the following steps: the method also comprises steps of hydrolytic acidification and aerobic and/or anaerobic biochemical reaction after flocculation precipitation.

8. The method for improving the efficiency of iron-carbon micro-electrolysis reaction by using the iron-containing waste acid liquor wastewater as claimed in claim 7, wherein the method comprises the following steps: the reaction process is accelerated by adopting an aeration mode in the iron-carbon micro-electrolysis reaction process.

9. The method for improving the efficiency of iron-carbon micro-electrolysis reaction by using the iron-containing waste acid liquor wastewater as claimed in claim 8, wherein the method comprises the following steps: the noble metal element comprises vanadium and/or platinum elements.

10. The method for improving the efficiency of iron-carbon micro-electrolysis reaction by using the iron-containing waste acid liquor wastewater as claimed in claim 9, wherein the method comprises the following steps: the filler in the iron-carbon micro-electrolysis reaction is prepared from waste acid liquor containing iron.

Technical Field

The invention relates to a method for treating refractory organic matters in wastewater by using iron-containing waste acid liquor, belonging to the field of wastewater treatment and waste acid recycling.

Background

The wastewater generated in the industries of petrochemical industry, industrial metallurgy, electroplating, papermaking, medicine and the like has complex components, poor biodegradability and high toxicity, and can be subjected to further biochemical treatment after pretreatment. The iron-carbon micro-electrolysis technology is coupled with the Fenton oxidation technology due to simple process, convenient operation and higher pretreatment effect, and is taken as a pretreatment measure of the wastewater difficult to degrade. The iron-carbon microelectrolysis is characterized by that it utilizes iron-carbon filler iron filings and carbon granules to form several tiny primary batteries, and in the action space an electric field is formed, so that it is nascent]、Fe²⁺The oxidation-reduction reaction is carried out with the organic matters in the environment, certain groups in the organic matters are destroyed and even broken chains are formed, the effect of decomposing the organic matters is achieved, and simultaneously the generated Fe²⁺Further oxidized to Fe³⁺And the hydrates of the compounds have stronger adsorption flocculation effect and realize the adsorption of organic matters.

In the practical application process, however, the iron-carbon micro-electrolysis is easy to passivate along with the reaction, so that the degradation of organic matters by the iron-carbon micro-electrolysis is greatly reduced. The reason for the iron-carbon micro-electrolysis passivation is that after the zero-valent iron in the iron-carbon filler is put into water, a layer of compact oxide film is rapidly generated on the surface under the action of a phase film, so that the conductivity of the primary battery formed by the iron-carbon filler is reduced, and the passivation phenomenon begins to occur. The iron-carbon filler is passivated to generate a channeling effect, reduce the contact area between water and the filler, influence the treatment effect of wastewater, need to frequently replace the filler and have large workload.

Based on the defects, the application with the Chinese patent application number of CN2010200003740 and the publication date of 2010, 11 and 3 discloses a reinforced iron-carbon micro-electrolysis reactor, which comprises a reaction container for containing iron-carbon filler, and is characterized in that more than two bearing layers are arranged in the reaction container at intervals along the vertical direction, aeration and back washing devices are respectively arranged on each bearing layer, and a plurality of through holes are arranged on each bearing layer. The application with the Chinese patent application number of CN201510128960.0 and the publication date of 2016, 4, month and 13 discloses a reinforced iron-carbon micro-electrolysis reactor, and discloses an iron-carbon micro-electrolysis device and a use method thereof. The application adopts the upflow type water inlet, evenly distributes water through the rotation of the impeller and the annular water distribution pipe, increases the stirring and friction effects of the filler and the sewage in the horizontal and vertical directions, and solves the common problems of iron-carbon bed layer blockage, hardening, passivation and the like of the existing iron-carbon micro-electrolysis reactor.

The method of the application is to increase the disturbance and friction between the filler and the sewage in the iron-carbon micro-electrolysis reaction through water distribution or aeration, and although the passivation of the filler can be effectively prevented, the modification of the device system is more complex and the modification cost is higher.

A large amount of waste acid liquor is usually generated in the electroplating industry and the steel smelting industry, the acid content in the waste acid liquor is about 1-10%, and the waste acid liquor contains a large amount of ferrous chloride and a few of trace precious metal elements such as vanadium, platinum and other metals. At present, the iron-containing waste acid is treated in a neutralization mode conventionally, a large amount of precipitates are generated while acid is wasted, the waste water treatment cost is increased, and meanwhile, the waste of resources is caused.

Based on the defects of the prior art, the invention is needed to provide a method which can effectively improve the reaction efficiency of iron-carbon micro-electrolysis and can recycle the iron-containing waste acid liquor.

Disclosure of Invention

1. Technical problem to be solved by the invention

Aiming at the problems of more complicated device system modification and higher cost of the method for improving the iron-carbon micro-electrolysis reaction efficiency in the prior art and the problem of low resource degree of the iron-containing waste acid solution, the invention provides the method for effectively improving the iron-carbon micro-electrolysis reaction efficiency by utilizing the iron-containing waste acid solution, which utilizes an acidic system in the iron-containing waste acid solution to adjust the pH environment of the iron-carbon micro-electrolysis reaction system and utilizes a large amount of Fe in the acid solution on the other hand²⁺The iron-carbon composite filler has the function of electron transfer, inhibits the oxidation of the surface of an iron simple substance serving as the filler, prevents the formation of a compact oxide layer on the iron-carbon filler, and prevents passivation, thereby improving the reaction efficiency of iron-carbon micro-electrolysis. Furthermore, the invention utilizes the catalytic action of noble metal to obviously reduce the activation energy of chain scission of organic matters, and further improves the reaction efficiency of iron-carbon micro-electrolysis.

2. Technical scheme

The invention provides a method for improving iron-carbon micro-electrolysis reaction efficiency by using iron-containing waste acid liquor wastewater, which is characterized in that in the process of removing difficultly-degraded organic matters in organic wastewater by using iron-carbon micro-electrolysis reaction, Fe-containing is added before and/or during the iron-carbon micro-electrolysis reaction²⁺The waste acid liquid containing iron also contains precious metal elements.

As a further improvement of the invention, the iron-containing waste acid liquor wastewater comprises any one or a combination of pickling waste liquor in the steel industry, pickling waste liquor in the electroplating industry and pickling liquor in the coal ash-to-alumina industry.

As a further improvement of the method, when the iron-containing waste acid liquid wastewater is added before the iron-carbon micro-electrolysis reaction, when the pH value of the wastewater is less than or equal to 2, adjusting the pH value of inlet water to 2-4 by using alkali liquor, and then adding the iron-containing waste acid liquid wastewater; when the pH value of the organic wastewater is more than 2 and less than 4, directly adding the iron-containing waste acid liquid wastewater; when the pH value of the organic wastewater is more than or equal to 4, directly adjusting the pH value of the iron-containing waste acid liquor wastewater to 2-4, and/or adjusting the pH value of the organic wastewater to 2-4 by using the iron-containing waste acid liquor wastewater and industrial strong acid in a synergistic manner.

As a further improvement of the invention, the method specifically comprises a flocculation precipitation step after the iron-carbon micro-electrolysis reaction: and (3) flocculating and precipitating the effluent after the iron-carbon micro-electrolysis reaction, and taking the precipitated effluent to detect the concentration of organic matters in the wastewater.

As a further improvement of the invention, the method specifically comprises a fenton oxidation treatment step, wherein the effluent after the iron-carbon micro-electrolysis reaction enters a fenton oxidation reaction unit for treatment, and the effluent after the fenton oxidation reaction is subjected to flocculation precipitation, and the effluent detects the concentration of organic matters in the wastewater.

As a further improvement of the invention, the organic wastewater comprises any one or combination of nitrobenzene production wastewater, medical wastewater, printing and dyeing wastewater and petrochemical comprehensive wastewater.

As a further improvement of the invention, the method also comprises the steps of hydrolytic acidification and aerobic and/or anaerobic biochemical reaction after flocculation precipitation.

As a further improvement of the invention, an aeration mode is adopted in the iron-carbon micro-electrolysis reaction process to accelerate the reaction process.

As a further development of the invention, the noble metal element comprises vanadium and/or platinum elements.

As a further improvement of the invention, the filler in the iron-carbon micro-electrolysis reaction is prepared by using iron-containing waste acid liquor wastewater.

3. Advantageous effects

Compared with the prior art, the technical scheme provided by the invention has the following beneficial effects:

(1) the method for improving the iron-carbon micro-electrolysis reaction efficiency by using the iron-containing waste acid liquor wastewater prevents the passivation problem of iron-carbon micro-electrolysis by using a large amount of ferrous ions contained in the waste acid liquor. The main reason for the passivation of the iron-carbon filler in the iron-carbon micro-electrolysis unit is caused by the poor conductivity of the wastewater due to the formation of a compact oxide film on the surface of the iron-carbon. The invention utilizes Fe²⁺The iron-carbon microelectrolysis treatment device belongs to a transition state ion form, has an electron transfer effect, can inhibit the oxidation of the surface of metal iron, further prevents the formation of a compact oxide layer on an iron-carbon filler, can effectively prevent the passivation of the iron-carbon filler, and enhances the treatment effect of an iron-carbon microelectrolysis unit on organic matters, and besides, for organic wastewater with the pH value of more than or equal to 4, the iron-carbon microelectrolysis treatment device utilizes an acidic system of iron-containing waste acid liquid as a pH regulator of the iron-carbon microelectrolysis, introduces ferrous ions in the process of regulating the pH value, is simple to operate, can recycle the waste acid liquid, and can effectively improve the iron-carbon microelectrolysis reaction efficiency.

(2) The method for improving the iron-carbon micro-electrolysis reaction efficiency by using the iron-containing waste acid liquor wastewater provided by the invention has the advantages that the iron-carbon micro-electrolysis degradation of organic matters is realized, the activation energy of chain scission of the organic matters is obviously reduced, and the treatment effect of the iron-carbon micro-electrolysis is improved by using the catalytic action of precious metals contained in the iron-containing waste acid liquor. In general, pickling waste liquid generated in the steel industry and pickling waste liquid generated in the electroplating industry contain a certain amount of precious metal elements (such as vanadium, platinum and other elements), so that a catalyst component is introduced while the iron-containing waste acid liquid in the industries is utilized, and the treatment effect of iron-carbon micro-electrolysis is remarkably improved.

(3) According to the method for improving the iron-carbon micro-electrolysis reaction efficiency by using the waste water containing the iron acid pickle, when the iron-carbon micro-electrolysis reaction unit and the Fenton oxidation reaction unit are coupled to treat the waste water containing the refractory organic matters, the waste water containing the iron acid pickle can be added to fully utilize H in the iron acid pickle⁺、Fe²⁺While the passivation of the iron-carbon filler is prevented, the dosage of ferrous iron in the rear-end Fenton oxidation unit is effectively reduced, and the Fe in the waste acid liquid is fully exerted²⁺Reducing the treatment cost of the wastewater and simultaneously enlarging the iron contentThe resource utilization range of the waste acid liquid.

(4) The method for improving the iron-carbon micro-electrolysis reaction efficiency by using the waste acid liquid containing iron can recycle the waste acid liquid, and the conventional waste acid liquid containing iron often has more impurity factors in the process of recycling iron salt or iron yellow and is difficult to recycle.

(5) The method for improving the iron-carbon micro-electrolysis reaction efficiency by using the iron-containing waste acid liquid wastewater greatly reduces the wastewater treatment cost of enterprises on the whole, and greatly reduces the wastewater treatment cost while obviously reducing the waste acid treatment cost. The conventional ferrous chloride and precious metal catalyst have high cost, and the wastewater treatment cost can be greatly increased if industrial-grade products are adopted, while the wastewater generated in the steel industry, the electroplating industry and the like is adopted in the invention, and the wastewater contains a large amount of ferrous and precious metals, so that the ideal removal effect is obtained, and the wastewater treatment cost of enterprises is greatly reduced.

Detailed Description

For a further understanding of the present invention, the method of the present invention is further described below with reference to the following examples.