Method for treating epichlorohydrin wastewater by using iron-copper supported catalyst

Abstract

The invention relates to a method for treating epichlorohydrin wastewater by using an iron-copper supported catalyst. The treatment method comprises the steps of preparing the iron-copper supported catalyst, adjusting the pH value of the epichlorohydrin wastewater, oxidizing the epichlorohydrin wastewater and the like. The epichlorohydrin wastewater treatment method is simple in technological process, easy and convenient to operate and mild in treatment condition, iron and copper metal ions are fixed to the surfaces of the aluminum oxide balls, the problem of iron / copper sludge is solved, the TOC degradation rate reaches 90% or above through the synergistic effect of the iron and copper metal ions, and therefore the epichlorohydrin wastewater treatment method has extremely good market application prospects.

Description

[Technical field]

[0001] The present invention belongs to the technical field of wastewater treatment. More specifically, the present invention relates to a method for treating epichlorohydrin wastewater using an iron-copper supported catalyst. [Background technology]

[0002] High-salinity organic wastewater is a typical type of difficult-to-treat wastewater, which contains a large amount of salt (Cl - 、Na + Plasma) and high-concentration organic pollutants. Representative high-salt organic wastewaters are leachate, oil production wastewater and resin production wastewater. Fenton oxidation is mainly suitable for the treatment of wastewater containing refractory organic matter. It has the advantages of simple equipment and wide application range. However, the traditional Fenton oxidation method has high treatment cost and is prone to produce a large amount of iron mud, which increases the secondary treatment cost. For example, Tusar N N, Maucec D, Rangus M, et al. "Manganese Functionalized Silicate Nanoparticles as a Fenton-Type Catalyst for Water Purification by Advanced Oxidation Processes (AOP)", Advanced Functional Materials, 2012, 22 (4): 820-826. DOI: 10.1002 / adfm.201102361. The disclosed Fenton-like method shows obvious advantages over the Fenton method in terms of catalyst types, treatment efficiency, cost and secondary pollution. These advantages make the Fenton-like method have a wide application prospect in the field of wastewater treatment. However, the Fenton-like method has technical defects such as pH applicable range and insufficient activity, which will affect its practical application effect. For details, see the literature: Liu Qiang, Sun Wei, Jiang Chengchun et al., "Preparation of Cu-Co modified MCM-41 catalyst and its degradation performance of nitrobenzene", "Industrial Catalysis", 2022(030-004).DOI:10.3969 / j.issn.1008-1143.2022.04.006.

[0003] In order to solve the defects of the prior art, the inventor has finally completed the present invention after a lot of experimental research and analysis and summary. [Summary of the invention]

[0004] [Technical issues to be solved]

[0005] The object of the present invention is to provide a method for treating epichlorohydrin wastewater using an iron-copper supported catalyst.

[0006] [Technical solution]

[0007] The present invention is achieved through the following technical solutions.

[0008] The invention relates to a method for treating epichlorohydrin wastewater by using an iron-copper supported catalyst.

[0009] The processing steps of this processing method are as follows:

[0010] A. Preparation of Iron-Copper Supported Catalyst

[0011] The alumina balls are immersed in a mixed solution of ferric nitrate and copper nitrate with a total metal ion concentration of 0.01 to 0.5 mol / L at room temperature for 1 to 3 hours, followed by suction filtration, drying, and calcination to obtain the iron-copper supported catalyst;

[0012] B. pH adjustment of epichlorohydrin wastewater

[0013] Epichlorohydrin wastewater is sent to the regulating tank 1 from the upper part through a pipeline, and the resistance heater 2 located on the side wall of the middle part of the regulating tank 1 and the stirrer 3 located on the top of the regulating tank 1 and overlapping with the central axis of the regulating tank 1 are turned on. At the same time, a pH regulator of hydrochloric acid aqueous solution with a concentration of 10-20% by weight is also sent to the top of the regulating tank 1 through a pipeline. The epichlorohydrin wastewater and the pH regulator are stirred at a temperature of 50-80° C. and the stirrer 3 to obtain epichlorohydrin wastewater with a pH value of 6-9;

[0014] C. Epichlorohydrin wastewater oxidation

[0015] The epichlorohydrin waste water with a pH value of 6 to 9 obtained in step B is sent to the oxidation reaction tower 5 from the lower part of the oxidation reaction tower 5 through a pipeline and a pump 4, and hydrogen peroxide is sent to the oxidation reaction tower 5 at the same flow rate through three inlets located at the upper part, the middle part and the lower part of the oxidation reaction tower 5 through a pipeline, and air is sent to the oxidation reaction tower 5 from the bottom of the oxidation reaction tower 5. At the same time, oscillator No. 1 6, oscillator No. 2 7 and oscillator No. 3 8 are turned on, and the epichlorohydrin waste water with a pH value of 6 to 9 and the hydrogen peroxide are oxidized for 1 to 3 hours in the presence of the above-mentioned iron-copper supported catalyst, and the qualified treated water is discharged from the upper part of the oxidation reaction tower 5 through a pipeline, and the reaction tail gas is discharged from the top of the oxidation reaction tower 5 through a pipeline.

[0016] According to a preferred embodiment of the present invention, in step A, the alumina ball is an α-Al2O3 particle ball with a diameter of 2 to 15 mm.

[0017] According to another preferred embodiment of the present invention, in step A, the mass ratio of ferric nitrate to copper nitrate in the mixed solution is 1:1-10.

[0018] According to another preferred embodiment of the present invention, in step A, the filter cake obtained by filtration is dried at a temperature of 80-110° C. until its water content is less than 0.5% by weight, and the dried filter cake is calcined at a temperature of 200-500° C. in an air or oxygen atmosphere for 1-3 hours.

[0019] According to another preferred embodiment of the present invention, in step A, the iron of the iron-copper supported catalyst is Fe2O3 with a content of 0.04-0.5% by weight, and the copper thereof is CuO with a content of 0.03-0.2% by weight.

[0020] According to another preferred embodiment of the present invention, in step B, the epichlorohydrin wastewater is an organic wastewater with a CaCl2 content of 12 to 18% by weight and a TOC of 2000 to 3600 mg / L and a pH of 11 to 13.

[0021] According to another preferred embodiment of the present invention, in step C, the oxidation reaction tower 5 is a reaction tower in which three layers of fixed beds of titanium steel plates with small holes are arranged from top to bottom, and the above-mentioned iron-copper loaded catalyst and oscillator No. 1 6, oscillator No. 2 7 and oscillator No. 3 8 are respectively placed on these titanium steel plate fixed beds.

[0022] According to another preferred embodiment of the present invention, in step C, oscillator No. 1 6 , oscillator No. 2 7 and oscillator No. 3 8 are reciprocating oscillators with an amplitude of 10 to 100 mm and a frequency of 50 to 200 times / min.

[0023] According to another preferred embodiment of the present invention, in step C, the volume ratio of epichlorohydrin wastewater with a pH value of 6-9 to hydrogen peroxide is 5-14:1; the volume ratio of epichlorohydrin wastewater with a pH value of 6-9 to air is 1:20-40.

[0024] According to another preferred embodiment of the present invention, in step C, the calcium chloride content of the qualified treated water is less than 18% by weight, and the TOC is less than 150 mg / L.

[0025] The present invention will be described in more detail below.

[0026] The present invention relates to a method for treating epichlorohydrin wastewater using an iron-copper supported catalyst. Aiming at the technical problems existing in the prior art, the inventor provides a method for treating epichlorohydrin wastewater using an iron-copper supported catalyst, wherein a catalyst is selected to perform a heterogeneous oxidation reaction at a high temperature, thereby avoiding the generation of iron / copper mud, and the bimetallic synergy improves the utilization efficiency of hydrogen peroxide. Catalysts are placed in layers and hydrogen peroxide is added in stages to make the heterogeneous oxidation reaction more uniform. At the same time, the pH of the treated water does not need to be additionally adjusted, thereby saving the cost of secondary treatment.

[0027] The processing steps of this processing method are as follows:

[0028] A. Preparation of Iron-Copper Supported Catalyst

[0029] The alumina balls are immersed in a mixed solution of ferric nitrate and copper nitrate with a total metal ion concentration of 0.01 to 0.5 mol / L at room temperature for 1 to 3 hours, followed by suction filtration, drying, and calcination to obtain the iron-copper supported catalyst;

[0030] In the present invention, the alumina ball is an α-Al2O3 particle ball with a diameter of 2 to 15 mm. If the diameter of the α-Al2O3 particle ball is less than 2 mm, the catalyst is easily worn and broken, and the service life is shortened; if the diameter of the α-Al2O3 particle ball is greater than 15 mm, the gaps between the catalysts are too large, which easily causes the accumulation volume to increase, occupies more reaction tower volume, and increases the equipment cost; therefore, it is reasonable that the diameter of the α-Al2O3 particle ball is 2 to 15 mm; of course, the present invention can also use Al2O3 particles of other crystal forms, but they will not have any negative impact on the performance of the iron-copper supported catalyst of the present invention, and these crystal forms of Al2O3 particles are also within the scope of protection of the present invention. The α-Al2O3 used in the present invention is a product currently sold on the market, such as a product sold by Pingxiang Jianghua Environmental Protection Equipment Filler Co., Ltd. under the trade name of alumina filler.

[0031] In this step, the total metal ion concentration of the mixed solution of ferric nitrate and copper nitrate is 0.01-0.5 mol / L. If the total metal ion concentration of the mixed solution is less than 0.01 mol / L, the effective active sites on the surface of the prepared catalyst are too low, affecting the catalytic efficiency of the catalyst; if the total metal ion concentration of the mixed solution is greater than 0.5 mol / L, the mixed solution is easily deposited in the catalyst, causing micropore blockage and a decrease in the number of active sites, thereby reducing the catalytic efficiency of the catalyst. Therefore, it is reasonable that the total metal ion concentration of the mixed solution of ferric nitrate and copper nitrate is 0.01-0.5 mol / L, preferably 0.01-0.3 mol / L, and more preferably 0.01-0.2 mol / L.

[0032] The mass ratio of ferric nitrate to copper nitrate in the mixed solution is 1:1-10. If the mass ratio of ferric nitrate to copper nitrate is greater than 1:1, the reaction cycle speed of copper is faster than that of iron, and the proportion of copper in the reaction process is lower, thereby reducing the catalytic efficiency of the catalyst; if the mass ratio of ferric nitrate to copper nitrate is less than 1:10, the proportion of iron in the reaction process is too low, resulting in a weakening of the Fe-Cu synergistic effect, thereby reducing the catalytic efficiency of the catalyst. Therefore, it is appropriate that the mass ratio of ferric nitrate to copper nitrate is 1:1-10, preferably 1:2-8, and more preferably 1:3-6.

[0033] The alumina balls are immersed in a mixed solution of ferric nitrate and copper nitrate for 1 to 3 hours. If the immersion time is shorter than 1 hour, the alumina balls are very unevenly immersed in ferric nitrate and copper nitrate, which reduces the catalytic efficiency of the catalyst. If the immersion time is longer than 3 hours, the amount of ferric nitrate and copper nitrate immersed does not increase significantly, and the catalytic efficiency of the catalyst does not increase significantly, but the energy consumption increases significantly, and the catalyst preparation cost increases.

[0034] After the alumina balls are immersed in the mixed solution of ferric nitrate and copper nitrate, they need to be filtered, dried and calcined to obtain the iron-copper supported catalyst.

[0035] The filter cake obtained by filtration is dried at a temperature of 80 to 110° C. until its water content is less than 0.5% by weight. If the drying temperature of the filter cake is lower than 80° C., the drying time needs to be extended, and the preparation time increases; if the drying temperature of the filter cake is higher than 110° C., the catalyst cooling time is extended, and the waiting time increases; therefore, the drying temperature of the filter cake is suitable to be 80 to 110° C.; according to the conventional direct drying method (also known as the weight method) standard analysis method, the water content of the dried filter cake is less than 0.5% by weight. If its water content is higher than 0.5% by weight, a large amount of water vapor will be generated during the subsequent roasting process, which will cause the catalyst particles to stick together, reducing the active sites and catalytic activity.

[0036] Then, the dried filter cake is calcined at a calcination temperature of 200 to 500° C. in an air or oxygen atmosphere for 1 to 3 hours. Under the conditions of air or oxygen atmosphere, when the calcination time is within the range, if the calcination temperature is lower than 200° C., the iron and copper metal ions cannot be completely oxidized to form oxides and are fixed on the surface of the alumina balls, thereby reducing the catalytic efficiency of the catalyst; if the calcination temperature is higher than 500° C., the amount of iron and copper metal ions oxidized to form oxides will not increase significantly, but the energy consumed will increase significantly, thereby increasing the catalyst preparation cost.

[0037] Under the condition of air or oxygen atmosphere, when the calcination temperature is within the range, if the calcination time is shorter than 1 hour, the calcination time of the dried filter cake is insufficient, the iron and copper metal ions cannot be completely oxidized to form oxides, and the catalytic efficiency of the prepared catalyst is significantly reduced; if the calcination time is longer than 3 hours, the amount of iron and copper metal ions oxidized to form oxides does not increase significantly, but too much energy is consumed, and the catalyst preparation cost will increase significantly.

[0038] In the present invention, the air or oxygen atmosphere should be understood as the air or oxygen content in the atmosphere of the roasting equipment being 21% by volume or more.

[0039] According to the standard method of X-ray fluorescence spectrometer, the iron of the iron-copper supported catalyst prepared in this step is α-Fe2O3, and its content is 0.04-0.50% by weight of the iron-copper supported catalyst. The copper of the iron-copper supported catalyst is CuO, and its content is 0.03-0.20% by weight of the iron-copper supported catalyst.

[0040] According to the combustion oxidation-non-dispersive infrared absorption method standard (HJ501-2009), the TOC removal efficiency of the iron-copper supported catalyst prepared by the present invention reaches more than 90%. After being used for up to 2 months, its TOC removal efficiency can still reach more than 90% of the initial TOC removal efficiency of the catalyst.

[0041] The impregnation equipment, filtration equipment, drying equipment and roasting equipment used in this step are all equipment commonly used in the field of chemical technology and well known to those skilled in the art.

[0042] B. pH adjustment of epichlorohydrin wastewater

[0043] Epichlorohydrin wastewater is sent to the regulating tank 1 from the upper part through a pipeline, and the resistance heater 2 located on the side wall of the middle part of the regulating tank 1 and the stirrer 3 located on the top of the regulating tank 1 and overlapping with the central axis of the regulating tank 1 are turned on. At the same time, a pH regulator of hydrochloric acid aqueous solution with a concentration of 10-20% by weight is also sent to the top of the regulating tank 1 through a pipeline. The epichlorohydrin wastewater and the pH regulator are stirred at a temperature of 50-80° C. and the stirrer 3 to obtain epichlorohydrin wastewater with a pH value of 6-9;

[0044] The epichlorohydrin wastewater used in the present invention comes from the wastewater generated by the epichlorohydrin production process of Fujian Huanyang New Materials Co., Ltd. This epichlorohydrin wastewater is an organic wastewater with a calcium chloride content of 12-18% by weight, a TOC of 2000-3600 mg / L, and a pH of 11-13.

[0045] The pH regulator used in the present invention is a hydrochloric acid solution with a concentration of 10 to 20% by weight. It is not advisable to exceed the above range because too high a pH regulator concentration will hinder the Fe 3+ Reduced to Fe 2+ The catalytic activity of iron is reduced; when the pH is too low, ferrous ions (Fe 2+ ) and iron ions (Fe 3+ ) easily reacts with hydroxide ions (OH - ) to form iron hydroxide (Fe(OH)3) precipitate, which reduces the catalytic activity.

[0046] The epichlorohydrin wastewater and the pH regulator are stirred and mixed at a temperature of 50 to 80° C. under stirring by the stirrer 3 to obtain epichlorohydrin wastewater with a pH value of 6 to 9.

[0047] In the present invention, the temperature at which the epichlorohydrin wastewater and the pH regulator are stirred and mixed is 50 to 80° C. If the temperature is lower than 50° C., the epichlorohydrin wastewater and the pH regulator are not fully mixed, the subsequent oxidation reaction acceleration effect is weakened, and it is difficult to achieve a good TOC removal effect; if the temperature is higher than 80° C., the energy consumption is increased and the preparation cost is increased.

[0048] The pH value of the epichlorohydrin wastewater obtained in this step is 6 to 9. If the pH value of the epichlorohydrin wastewater is less than 6, it will inhibit the decomposition of organic matter and corrode the pipeline, making it difficult to achieve a good TOC removal effect; if the pH value of the epichlorohydrin wastewater is higher than 9, the pH value of the effluent obtained in the subsequent treatment step will be too high and will not meet the direct discharge standard. Therefore, the pH value of the epichlorohydrin wastewater is appropriately 6 to 9, and preferably the pH value is 6.6 to 8.5.

[0049] The regulating tank 1 used in the present invention is a reaction tank with stirring and heating functions. A resistance heater 2 is arranged on the side wall of the middle part of the regulating tank 1. A stirrer 3 is arranged at the top of the regulating tank 1 and overlaps with the central axis of the regulating tank 1.

[0050] The adjustment tank used in the present invention is a product currently sold on the market, such as a product sold by Zhejiang Chuan Ning Environmental Protection Technology Co., Ltd. under the trade name of reaction tank.

[0051] C. Epichlorohydrin wastewater oxidation

[0052] The epichlorohydrin waste water with a pH value of 6 to 9 obtained in step B is sent to the oxidation reaction tower 5 from the lower part of the oxidation reaction tower 5 through a pipeline and a pump 4, and hydrogen peroxide is sent to the oxidation reaction tower 5 at the same flow rate through three inlets located at the upper part, the middle part and the lower part of the oxidation reaction tower 5 through a pipeline, and air is sent to the oxidation reaction tower 5 from the bottom of the oxidation reaction tower 5. At the same time, oscillator No. 1 6, oscillator No. 2 7 and oscillator No. 3 8 are turned on, and the epichlorohydrin waste water with a pH value of 6 to 9 and the hydrogen peroxide are oxidized for 1 to 3 hours in the presence of the above-mentioned iron-copper supported catalyst, and the qualified treated water is discharged from the upper part of the oxidation reaction tower 5 through a pipeline, and the reaction tail gas is discharged from the top of the oxidation reaction tower 5 through a pipeline.

[0053] In this step, the concentration of the hydrogen peroxide is 27.5-30.0% by weight of hydrogen peroxide. The hydrogen peroxide used in the present invention is a product currently sold on the market, such as a product sold by Jinke Hydrogen Peroxide Co., Ltd. under the trade name hydrogen peroxide.

[0054] In the present invention, the volume ratio of epichlorohydrin wastewater with a pH value of 6 to 9 to hydrogen peroxide is 5 to 14:1; if the volume ratio of epichlorohydrin wastewater to hydrogen peroxide is less than 5:1, a large amount of hydrogen peroxide will be wasted, increasing the treatment cost; if the volume ratio of epichlorohydrin wastewater to hydrogen peroxide is greater than 14:1, the discharged wastewater will be unqualified, that is, the TOC is higher than 150 mg / L; therefore, it is reasonable that the volume ratio of epichlorohydrin wastewater to hydrogen peroxide is 5 to 14:1, preferably 6 to 10:1.

[0055] The volume ratio of epichlorohydrin wastewater with a pH value of 6 to 9 to air is 1:20 to 40. If the volume ratio of epichlorohydrin wastewater to air is greater than 1:20, the TOC removal effect will be affected due to insufficient aeration; if the volume ratio of epichlorohydrin wastewater to air is less than 1:40, the oxidation reaction cost will increase; therefore, the volume ratio of epichlorohydrin wastewater to air is 1:20 to 40, preferably 1:26 to 35;

[0056] Epichlorohydrin wastewater with a pH value of 6 to 9 is subjected to oxidation reaction with hydrogen peroxide in the presence of the above-mentioned iron-copper supported catalyst for 1 to 3 hours. If the oxidation reaction time of epichlorohydrin wastewater with a pH value of 6 to 9 with hydrogen peroxide is shorter than 1 hour, the oxidation reaction is not thorough and the treatment effect of epichlorohydrin wastewater is poor; if the oxidation reaction time of epichlorohydrin wastewater with a pH value of 6 to 9 with hydrogen peroxide is longer than 3 hours, the service life of the catalyst will be shortened, the catalyst utilization rate will be reduced, and the treatment cost will be increased; therefore, the oxidation reaction time of epichlorohydrin wastewater with a pH value of 6 to 9 with hydrogen peroxide is appropriately 1 to 3 hours, preferably 1.2 to 2.8 hours, and more preferably 1.5 to 2.4 hours;

[0057] The oxidation reaction tower 5 used in the present invention is a reaction tower in which three layers of titanium steel plate fixed beds with small holes are arranged from top to bottom. The above-mentioned iron-copper loaded catalyst and oscillator No. 1 6, oscillator No. 2 7 and oscillator No. 3 8 are placed on these titanium steel plate fixed beds respectively.

[0058] The titanium steel plate with small holes is a titanium steel plate with a thickness of 8 to 20 mm and a diameter the same as the inner diameter of the oxidation reaction tower 5. 1,000 to 10,000 straight through holes with a diameter of 1.5 to 14 mm are arranged on the titanium steel plate, and these straight through holes are evenly distributed according to certain geometric rules.

[0059] The oscillator No. 1 6, oscillator No. 2 7 and oscillator No. 3 8 are reciprocating oscillators, the amplitude of which is 10 to 100 mm and the frequency of which is 50 to 200 times / min.

[0060] The oxidation reaction tower 5 used in the present invention is a product currently sold on the market, such as a product sold by Zhejiang Chuan Ning Environmental Protection Technology Co., Ltd. under the trade name of reaction tower.

[0061] The pump 4 used in the present invention is a centrifugal pump, which is a product currently sold on the market, for example, a product sold by Shanghai Sunshine Pump Manufacturing Co., Ltd. under the trade name FP type reinforced polypropylene centrifugal pump.

[0062] In the present invention, the qualified treated water should be a discharged water discharged from the upper part of the oxidation reaction tower 5 and conforming to the standard specified in GB8978-1996.

[0063] According to the standard analysis method for industrial calcium chloride (GB / T23941-2009), the calcium chloride content of the qualified treated water is less than 18% by weight; according to the combustion oxidation-non-dispersive infrared absorption method (HJ501-2009), the TOC of the qualified treated water is less than 150 mg / L.

[0064] The TOC degradation rate of epichlorohydrin wastewater in the treatment method of the present invention is calculated according to the following formula:

[0065]

[0066] For the specific implementation effect of using iron-copper supported catalyst to treat epichlorohydrin wastewater, please refer to the subsequent specific implementation method section.

[0067] [Beneficial Effects]

[0068] The beneficial technical effects of the present invention are:

[0069] Both Fe and Cu have the properties of Fenton reagent, which can catalyze H2O2 to produce hydroxyl radicals, which can react with organic matter and decompose it into harmless small molecules, such as water and carbon dioxide. The supported catalyst of the present invention is a catalyst with iron and copper ions fixed on the surface of aluminum oxide particles, which can avoid the generation of iron / copper mud and reduce the metal dissolution rate. The iron and copper supported catalyst of the present invention improves the efficiency of organic matter treatment and the scope of use of the material is wider. The material has good durability and can be used repeatedly. In the reaction process, the catalyst is placed in layers and the addition of hydrogen peroxide is adjusted in stages to make the reaction more sufficient and uniform. The catalyst layer is provided with an oscillator to prevent caking. The pH of the reaction water is neutral and the chromaticity is low, and no subsequent secondary treatment is required. The one-time process achieves a good organic matter treatment effect, and the various levels of standards in the "Comprehensive Sewage Discharge Standard" (GB8978-1996) are reached by adding different amounts of hydrogen peroxide and catalyst.

Brief Description of the Drawings

[0070] Attached Figure 1 The present invention is a schematic diagram of the process flow of treating epichlorohydrin wastewater using an iron-copper supported catalyst.

[0071] In the figure:

[0072] 1-adjusting tank; 2-resistance heater; 3-agitator; 4-pump; 5-oxidation reaction tower; 6-oscillator No. 1; 7-oscillator No. 2; 8-oscillator No. 3. [Specific implementation method]

[0073] The present application is further described in detail below with reference to the embodiments.

[0074] Example 1: Epichlorohydrin wastewater treatment method of the present invention

[0075] The implementation steps of this embodiment are as follows:

[0076] A. Preparation of Iron-Copper Supported Catalyst

[0077] Allow α-Al2O3 alumina balls with a diameter of 2 to 6 mm to be immersed in a solution of ferric nitrate and copper nitrate mixed (iron nitrate and copper nitrate mass ratio of 1:7) with a total metal ion concentration of 0.04 mol / L at room temperature for 2 hours, then use a suction filtration device sold by Gongyi Yuhua Instrument Co., Ltd. under the trade name of circulating water vacuum pump for suction filtration, and use a drying device sold by Shanghai Yiheng Scientific Instrument Co., Ltd. under the trade name of blast drying oven to dry the filter cake at a temperature of 100°C until its water content is less than 0.5% by weight, and then use a roasting device sold by Beijing Anhe Meicheng Scientific Instrument Co., Ltd. under the trade name of ceramic fiber muffle furnace to roast for 1.6 hours at a roasting temperature of 400°C in an air atmosphere. According to the method described in the specification of this application, the α-Fe2O3 content of the roasted product is 0.50% by weight, and the CuO content is 0.03% by weight. The roasted product is the iron-copper supported catalyst;

[0078] B. pH adjustment of epichlorohydrin wastewater

[0079] Epichlorohydrin wastewater with a pH value of 11.6 and a calcium chloride content of 14% by weight and a TOC of 3600 mg / L discharged by Fujian Huanyang New Materials Co., Ltd. is sent to the tank through a pipeline from the upper part of an adjusting tank 1 sold by Zhejiang Chuanning Environmental Protection Technology Co., Ltd. under the trade name of a reaction tank, and a resistance heater 2 located on the side wall of the middle part of the adjusting tank 1 and a stirrer 3 located on the top of the adjusting tank 1 and overlapping with the central axis of the adjusting tank 1 are turned on. At the same time, a hydrochloric acid aqueous solution pH regulator with a concentration of 20% by weight is also sent to the top of the adjusting tank 1 through a pipeline. The epichlorohydrin wastewater and the pH regulator are stirred at a temperature of 60° C. and by the stirrer 3 to obtain epichlorohydrin wastewater with a pH value of 8.1;

[0080] C. Epichlorohydrin wastewater oxidation

[0081] The epichlorohydrin wastewater with a pH value of 8.1 obtained in step B is sent from the lower part of the oxidation reaction tower 5 to the oxidation reaction tower 5 sold by Zhejiang Chuan Ning Environmental Protection Technology Co., Ltd. under the trade name of reaction tower through a pipeline and a pump 4 sold by Shanghai Sunshine Pump Manufacturing Co., Ltd. under the trade name of FP type reinforced polypropylene centrifugal pump. Hydrogen peroxide is sent to the oxidation reaction tower 5 through a pipeline from three inlets located at the upper part, middle part and lower part of the oxidation reaction tower 5 at the same flow rate. Among them, the volume ratio of the epichlorohydrin wastewater with a pH value of 8.1 to the hydrogen peroxide is 10:1, and the air is The bottom of the oxidation reaction tower 5 is sent to the oxidation reaction tower 5, the volume ratio of the epichlorohydrin wastewater with a pH value of 8.1 to the air is 1:40, and the No. 1 oscillator 6, the No. 2 oscillator 7 and the No. 3 oscillator 8 are turned on at the same time, and their amplitude is 70mm, and their frequency is 150 times / min. The epichlorohydrin wastewater with a pH value of 8.1 and the hydrogen peroxide are oxidized for 1.6 hours in the presence of the above-mentioned iron-copper supported catalyst, and the qualified treated water is discharged from the upper part of the oxidation reaction tower 5 through a pipeline, and the reaction tail gas is discharged from the top of the oxidation reaction tower 5 through a pipeline. According to the detection method described in the specification of this application, the calcium chloride content of the qualified treated water is 10% by weight, and its TOC is 150mg / L, which meets the Class III water standard specified in the "Comprehensive Sewage Discharge Standard" (GB8978-1996).

[0082] According to the calculation described in the specification of this application, the TOC degradation rate of epichlorohydrin wastewater in the treatment method of this embodiment reaches 90.0%.

[0083] Example 2: Epichlorohydrin wastewater treatment method of the present invention

[0084] The implementation steps of this embodiment are as follows:

[0085] A. Preparation of Iron-Copper Supported Catalyst

[0086] Allow α-Al2O3 alumina balls with a diameter of 5 to 9 mm to be immersed in a solution of ferric nitrate and copper nitrate mixed (iron nitrate and copper nitrate mass ratio of 1:3) with a total metal ion concentration of 0.01 mol / L at room temperature for 1 hour, then use a suction filtration device sold by Gongyi Yuhua Instrument Co., Ltd. under the trade name of circulating water vacuum pump for suction filtration, and use a drying device sold by Shanghai Yiheng Scientific Instrument Co., Ltd. under the trade name of blast drying oven to dry the filter cake at a temperature of 80°C until its water content is less than 0.5% by weight, and use a roasting device sold by Beijing Anhe Meicheng Scientific Instrument Co., Ltd. under the trade name of ceramic fiber muffle furnace to roast for 3.0 hours at a roasting temperature of 400°C and an oxygen atmosphere. According to the method described in the specification of this application, the α-Fe2O3 content of the roasted product is 0.03% by weight, and the CuO content is 0.09% by weight. The roasted product is the iron-copper supported catalyst;

[0087] B. pH adjustment of epichlorohydrin wastewater

[0088] Epichlorohydrin wastewater with a pH value of 11.0 and a calcium chloride content of 16% by weight and a TOC of 2000 mg / L discharged by Fujian Huanyang New Materials Co., Ltd. is sent to the tank through a pipeline from the upper part of an adjusting tank 1 sold by Zhejiang Chuanning Environmental Protection Technology Co., Ltd. under the trade name of a reaction tank, and a resistance heater 2 located on the side wall of the middle part of the adjusting tank 1 and a stirrer 3 located on the top of the adjusting tank 1 and overlapping with the central axis of the adjusting tank 1 are turned on. At the same time, a pH regulator of a hydrochloric acid aqueous solution with a concentration of 10% by weight is also sent to the top of the adjusting tank 1 through a pipeline. The epichlorohydrin wastewater and the pH regulator are stirred at a temperature of 70° C. and by the stirrer 3 to obtain epichlorohydrin wastewater with a pH value of 6.0;

[0089] C. Epichlorohydrin wastewater oxidation

[0090] The epichlorohydrin wastewater with a pH value of 8.1 obtained in step B is sent from the lower part of the oxidation reaction tower 5 to the oxidation reaction tower 5 sold by Zhejiang Chuan Ning Environmental Protection Technology Co., Ltd. under the trade name of reaction tower through a pipeline and a pump 4 sold by Shanghai Sunshine Pump Manufacturing Co., Ltd. under the trade name of FP type reinforced polypropylene centrifugal pump. Hydrogen peroxide is sent to the oxidation reaction tower 5 through a pipeline from three inlets located at the upper part, middle part and lower part of the oxidation reaction tower 5 at the same flow rate, wherein the volume ratio of the epichlorohydrin wastewater with a pH value of 6.0 to the hydrogen peroxide is 5:1, and the air is The bottom of the oxidation reaction tower 5 is sent to the oxidation reaction tower 5, the volume ratio of the epichlorohydrin wastewater with a pH value of 6.0 to the air is 1:20, and the No. 1 oscillator 6, the No. 2 oscillator 7 and the No. 3 oscillator 8 are turned on at the same time, and their amplitude is 10mm, and their frequency is 50 times / min. The epichlorohydrin wastewater with a pH value of 6.0 and the hydrogen peroxide are oxidized for 3.0 hours in the presence of the above-mentioned iron-copper supported catalyst, and the qualified treated water is discharged from the upper part of the oxidation reaction tower 5 through a pipeline, and the reaction tail gas is discharged from the top of the oxidation reaction tower 5 through a pipeline. According to the detection method described in the specification of this application, the calcium chloride content of the qualified treated water is 12% by weight, and its TOC is 10mg / L, which meets the Class III water standard specified in the "Comprehensive Sewage Discharge Standard" (GB8978-1996).

[0091] According to the calculation described in the specification of this application, the TOC degradation rate of epichlorohydrin wastewater in the treatment method of this embodiment reaches 99.3%.

[0092] Example 3: Epichlorohydrin wastewater treatment method of the present invention

[0093] The implementation steps of this embodiment are as follows:

[0094] A. Preparation of Iron-Copper Supported Catalyst

[0095] Allow α-Al2O3 alumina balls with a diameter of 8 to 12 mm to be immersed in a solution of ferric nitrate and copper nitrate mixed (iron nitrate and copper nitrate mass ratio of 1:4) with a total metal ion concentration of 0.02 mol / L at room temperature for 3 hours, then use a suction filtration device sold by Gongyi Yuhua Instrument Co., Ltd. under the trade name of circulating water vacuum pump for suction filtration, and use a drying device sold by Shanghai Yiheng Scientific Instrument Co., Ltd. under the trade name of blast drying oven to dry the filter cake at a temperature of 90°C until its water content is less than 0.5% by weight, and use a roasting device sold by Beijing Anhe Meicheng Scientific Instrument Co., Ltd. under the trade name of ceramic fiber muffle furnace to roast for 2.4 hours at a roasting temperature of 300°C and an air atmosphere. According to the method described in the specification of this application, the α-Fe2O3 content of the roasted product is 0.20% by weight, and the CuO content is 0.15% by weight. The roasted product is the iron-copper supported catalyst;

[0096] B. pH adjustment of epichlorohydrin wastewater

[0097] Epichlorohydrin wastewater with a pH value of 13.0 and a calcium chloride content of 12% by weight and a TOC of 2500 mg / L discharged by Fujian Huanyang New Materials Co., Ltd. is sent to the tank through a pipeline from the upper part of an adjusting tank 1 sold by Zhejiang Chuan Ning Environmental Protection Technology Co., Ltd. under the trade name of a reaction tank, and a resistance heater 2 located on the side wall of the middle part of the adjusting tank 1 and a stirrer 3 located on the top of the adjusting tank 1 and overlapping with the central axis of the adjusting tank 1 are turned on. At the same time, a pH regulator of a hydrochloric acid aqueous solution with a concentration of 12% by weight is also sent to the top of the adjusting tank 1 through a pipeline. The epichlorohydrin wastewater and the pH regulator are stirred at a temperature of 80° C. and by the stirrer 3 to obtain epichlorohydrin wastewater with a pH value of 9.0;

[0098] C. Epichlorohydrin wastewater oxidation

[0099] The epichlorohydrin wastewater with a pH value of 9.0 obtained in step B is sent from the lower part of the oxidation reaction tower 5 to the oxidation reaction tower 5 sold by Zhejiang Chuan Ning Environmental Protection Technology Co., Ltd. under the trade name of reaction tower through a pipeline and a pump 4 sold by Shanghai Sunshine Pump Manufacturing Co., Ltd. under the trade name of FP type reinforced polypropylene centrifugal pump. Hydrogen peroxide is sent to the oxidation reaction tower 5 through a pipeline from three inlets located at the upper part, middle part and lower part of the oxidation reaction tower 5 at the same flow rate. Among them, the volume ratio of the epichlorohydrin wastewater with a pH value of 9.0 to the hydrogen peroxide is 14:1, and the air The volume ratio of the epichlorohydrin wastewater with a pH value of 9.0 to air is 1:28, and the No. 1 oscillator 6, the No. 2 oscillator 7 and the No. 3 oscillator 8 are turned on at the same time, and their amplitude is 40 mm, and their frequency is 100 times / min. The epichlorohydrin wastewater with a pH value of 9.0 and the hydrogen peroxide are oxidized for 2.4 hours in the presence of the above-mentioned iron-copper supported catalyst, and the qualified treated water is discharged from the upper part of the oxidation reaction tower 5 through a pipeline, and the reaction tail gas is discharged from the top of the oxidation reaction tower 5 through a pipeline. According to the detection method described in the specification of this application, the calcium chloride content of the qualified treated water is 8% by weight, and its TOC is 18 mg / L, which meets the Class III water standard specified in the "Comprehensive Sewage Discharge Standard" (GB8978-1996).

[0100] According to the calculation described in the specification of this application, the TOC degradation rate of epichlorohydrin wastewater in the treatment method of this embodiment reaches 98.8%.

[0101] Example 4: Epichlorohydrin wastewater treatment method of the present invention

[0102] The implementation steps of this embodiment are as follows:

[0103] A. Preparation of Iron-Copper Supported Catalyst

[0104] Allow α-Al2O3 alumina balls with a diameter of 11 to 15 mm to be immersed in a solution of ferric nitrate and copper nitrate mixed (iron nitrate and copper nitrate mass ratio of 1:10) with a total metal ion concentration of 0.50 mol / L at room temperature for 2 hours, then use a suction filtration device sold by Gongyi Yuhua Instrument Co., Ltd. under the trade name of circulating water vacuum pump for suction filtration, and use a drying device sold by Shanghai Yiheng Scientific Instrument Co., Ltd. under the trade name of blast drying oven to dry the filter cake at a temperature of 110°C until its water content is less than 0.5% by weight, and then use a roasting device sold by Beijing Anhe Meicheng Scientific Instrument Co., Ltd. under the trade name of ceramic fiber muffle furnace to roast for 1.0 hour at a roasting temperature of 500°C and an air atmosphere. According to the method described in the specification of this application, the α-Fe2O3 content of the roasted product is 0.35% by weight, and the CuO content is 0.20% by weight. The roasted product is the iron-copper supported catalyst;

[0105] B. pH adjustment of epichlorohydrin wastewater

[0106] Epichlorohydrin wastewater with a pH value of 12.4 and a calcium chloride content of 18% by weight and a TOC of 3100 mg / L discharged by Fujian Huanyang New Materials Co., Ltd. is sent to the tank through a pipeline from the upper part of an adjusting tank 1 sold by Zhejiang Chuan Ning Environmental Protection Technology Co., Ltd. under the trade name of a reaction tank, and a resistance heater 2 located on the side wall of the middle part of the adjusting tank 1 and a stirrer 3 located on the top of the adjusting tank 1 and overlapping with the central axis of the adjusting tank 1 are turned on. At the same time, a hydrochloric acid aqueous solution pH regulator with a concentration of 16% by weight is also sent to the top of the adjusting tank 1 through a pipeline. The epichlorohydrin wastewater and the pH regulator are stirred at a temperature of 50° C. and by the stirrer 3 to obtain epichlorohydrin wastewater with a pH value of 7.3;

[0107] C. Epichlorohydrin wastewater oxidation

[0108] The epichlorohydrin wastewater with a pH value of 7.3 obtained in step B is sent from the lower part of the oxidation reaction tower 5 to the oxidation reaction tower 5 sold by Zhejiang Chuan Ning Environmental Protection Technology Co., Ltd. under the trade name of reaction tower through a pipeline and a pump 4 sold by Shanghai Sunshine Pump Manufacturing Co., Ltd. under the trade name of FP type reinforced polypropylene centrifugal pump. Hydrogen peroxide is sent to the oxidation reaction tower 5 through a pipeline from three inlets located at the upper part, middle part and lower part of the oxidation reaction tower 5 at the same flow rate. Among them, the volume ratio of the epichlorohydrin wastewater with a pH value of 7.3 to the hydrogen peroxide is 10:1, and the air is The bottom of the oxidation reaction tower 5 is sent to the oxidation reaction tower 5, the volume ratio of the epichlorohydrin wastewater with a pH value of 7.3 to the air is 1:34, and the No. 1 oscillator 6, the No. 2 oscillator 7 and the No. 3 oscillator 8 are turned on at the same time, and their amplitude is 100mm, and their frequency is 200 times / min. The epichlorohydrin wastewater with a pH value of 7.3 and the hydrogen peroxide are oxidized for 1.0h in the presence of the above-mentioned iron-copper supported catalyst, and the qualified treated water is discharged from the upper part of the oxidation reaction tower 5 through a pipeline, and the reaction tail gas is discharged from the top of the oxidation reaction tower 5 through a pipeline. According to the detection method described in the specification of this application, the calcium chloride content of the qualified treated water is 11% by weight, and its TOC is 32mg / L, which meets the Class III water standard specified in the "Comprehensive Sewage Discharge Standard" (GB8978-1996).

[0109] According to the calculation described in the specification of this application, the TOC degradation rate of epichlorohydrin wastewater in the treatment method of this embodiment reaches 98.1%.

Claims

1. A method for treating epichlorohydrin wastewater using an iron-copper supported catalyst, characterized in that The processing steps of this processing method are as follows: A. Preparation of Iron-Copper Supported Catalyst The alumina balls are immersed in a mixed solution of ferric nitrate and copper nitrate with a total metal ion concentration of 0.01 to 0.5 mol / L at room temperature for 1 to 3 hours, followed by suction filtration, drying, and calcination to obtain the iron-copper supported catalyst; B. pH adjustment of epichlorohydrin wastewater Epichlorohydrin wastewater is sent from the upper part of the regulating tank (1) into the tank through a pipeline, and the resistance heater (2) located on the side wall of the middle part of the regulating tank (1) and the stirrer (3) located on the top of the regulating tank (1) and overlapping with the central axis of the regulating tank (1) are turned on. At the same time, a pH regulator of a hydrochloric acid aqueous solution with a concentration of 10 to 20% by weight is also sent to the top of the regulating tank (1) through a pipeline. The epichlorohydrin wastewater and the pH regulator are stirred at a temperature of 50 to 80° C. and the stirrer (3) to obtain epichlorohydrin wastewater with a pH value of 6 to 9; C. Epichlorohydrin wastewater oxidation The epichlorohydrin wastewater with a pH value of 6 to 9 obtained in step B is sent to the oxidation reaction tower (5) from the lower part of the oxidation reaction tower (5) through a pipeline and a pump (4), hydrogen peroxide is sent to the oxidation reaction tower (5) through a pipeline from three inlets located at the upper part, the middle part and the lower part of the oxidation reaction tower (5) at the same flow rate, and air is sent to the oxidation reaction tower (5) from the bottom of the oxidation reaction tower (5), and at the same time, the No. 1 oscillator (6), the No. 2 oscillator (7) and the No. 3 oscillator (8) are turned on, and the epichlorohydrin wastewater with a pH value of 6 to 9 and the hydrogen peroxide are oxidized for 1 to 3 hours in the presence of the above-mentioned iron-copper supported catalyst, and the qualified treated water is discharged from the upper part of the oxidation reaction tower (5) through a pipeline, and the reaction tail gas is discharged from the top of the oxidation reaction tower (5) through a pipeline.

2. The epichlorohydrin wastewater treatment method according to claim 1, characterized in that In step A, the alumina ball is an α-Al2O3 particle ball with a diameter of 2 to 15 mm.

3. The epichlorohydrin wastewater treatment method according to claim 1, characterized in that In step A, the mass ratio of ferric nitrate to copper nitrate in the mixed solution is 1:1-10.

4. The epichlorohydrin wastewater treatment method according to claim 1, characterized in that In step A, the filter cake obtained by filtration is dried at a temperature of 80-110° C. until its water content is less than 0.5% by weight, and the dried filter cake is calcined at a temperature of 200-500° C. in an air or oxygen atmosphere for 1-3 hours.

5. The epichlorohydrin wastewater treatment method according to claim 1, characterized in that In step A, the iron of the iron-copper supported catalyst is Fe2O3 with a content of 0.04-0.50% by weight, and the copper thereof is CuO with a content of 0.03-0.20% by weight.

6. The epichlorohydrin wastewater treatment method according to claim 1, characterized in that In step B, the epichlorohydrin wastewater is an organic wastewater with a CaCl2 content of 12-18% by weight, a TOC of 2000-3600 mg / L and a pH of 11-13.

7. The epichlorohydrin wastewater treatment method according to claim 1, characterized in that In step C, the oxidation reaction tower (5) is a reaction tower in which three layers of titanium steel plate fixed beds with small holes are arranged from top to bottom. The above-mentioned iron-copper supported catalyst and oscillator No. 1 (6), oscillator No. 2 (7) and oscillator No. 3 (8) are placed on these titanium steel plate fixed beds respectively.

8. The epichlorohydrin wastewater treatment method according to claim 1 or 7, characterized in that In step C, oscillator No. 1 (6), oscillator No. 2 (7) and oscillator No. 3 (8) are reciprocating oscillators with an amplitude of 10 to 100 mm and a frequency of 50 to 200 times / min.

9. The epichlorohydrin wastewater treatment method according to claim 1, characterized in that In step C, the volume ratio of epichlorohydrin wastewater with a pH value of 6 to 9 to hydrogen peroxide is 5 to 14:1; the volume ratio of epichlorohydrin wastewater with a pH value of 6 to 9 to air is 1:20 to 40.

10. The epichlorohydrin wastewater treatment method according to claim 1, characterized in that In step C, the calcium chloride content of the qualified treated water is less than 18% by weight, and the TOC is less than 150 mg / L.

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