Photovoltaic aluminum profile anodic oxidation wastewater treatment method

Abstract

The invention relates to a photovoltaic aluminum profile anodic oxidation wastewater treatment method which comprises the following steps: carrying out acid-base neutralization treatment on raw water, feeding into an electrostatic spinning tank, filtering, and sequentially feeding into a cation exchange resin device and anion exchange resin. The method is few in treatment procedure, short in period, capable of completing treatment of one batch of photovoltaic aluminum profile anodic oxidation wastewater in one day, high in treatment efficiency, quite suitable for centralized treatment of photovoltaic aluminum profile anodic oxidation wastewater in industry and good in industrial application prospect.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to a method for treating photovoltaic aluminum profile anodizing wastewater. Background Art

[0002] Photovoltaic aluminum alloy anodizing wastewater is a special wastewater generated in the photovoltaic industry and aluminum alloy processing process, which usually contains a variety of pollutants, including grease, surfactants, alkali, acid, heavy metal ions (such as nickel ions, tin ions), dyes, additives and other trace pollutants. These pollutants come from various processes of anodizing, such as degreasing, alkaline etching, neutralization, anodizing, dyeing and sealing.

[0003] With the improvement of environmental awareness, the treatment of photovoltaic aluminum alloy anodizing wastewater has received more and more attention. At present, the treatment process of photovoltaic aluminum alloy anodizing wastewater mainly includes pretreatment, neutralization, coagulation and sedimentation, oxidation-reduction, biological treatment and deep treatment, as follows:

[0004] Pretreatment: Remove large suspended particles through grid filtration, sedimentation and other steps to reduce the burden of subsequent treatment.

[0005] Neutralization: Adjusting the pH of wastewater to neutral or near neutral for subsequent treatment. This step usually uses chemical reagents such as sulfuric acid or sodium hydroxide.

[0006] Coagulation and sedimentation: Add coagulants (such as polyaluminium chloride, ferrous sulfate, etc.) and flocculants (such as polyacrylamide) to the neutralized wastewater to condense the fine suspended matter into larger particles, which are then removed by sedimentation.

[0007] Oxidation-reduction: For wastewater containing difficult-to-degrade organic matter such as dyes and additives, oxidation-reduction methods such as Fenton oxidation and ozone oxidation can be used for treatment to decompose the organic matter into harmless substances.

[0008] Biological treatment: After pretreatment and coagulation and sedimentation, wastewater can enter the biological treatment unit for further treatment. Biological treatment units usually include biological contact oxidation tanks, secondary sedimentation tanks, etc., which remove organic matter and nutrients in wastewater through the metabolism of microorganisms.

[0009] Deep treatment: For wastewater with higher requirements, deep treatment such as reverse osmosis, ultrafiltration, ion exchange, etc. can be carried out to remove salt and other trace pollutants in the wastewater and improve the effluent quality.

[0010] It can be seen that the treatment process of photovoltaic aluminum alloy anodizing wastewater is long and inefficient. It usually takes 4-5 days to treat a batch of wastewater and meet the discharge standards. How to develop more efficient and economical wastewater treatment technology is the direction that industry researchers have been working hard on. Summary of the invention

[0011] The purpose of the present invention is to overcome the problems of long treatment process and low efficiency of the existing photovoltaic aluminum alloy anodizing wastewater, and to provide a photovoltaic aluminum profile anodizing wastewater treatment method. Through electrostatic spinning fiber membrane and resin adsorption technology, the process flow is greatly shortened, and the treatment cycle is compressed to 1 day, which greatly improves the sewage treatment efficiency. It is particularly suitable for large-scale centralized treatment of photovoltaic aluminum alloy anodizing wastewater.

[0012] The modified nanofiber membrane obtained by modification in the present invention can simultaneously remove multiple heavy metal pollutants, but it cannot effectively remove inorganic non-metallic pollutants and organic pollutants. For this reason, the inventors have conducted many experiments and tried a variety of filter materials. Finally, they found that a specific combination of cationic resin and anionic resin can cooperate with the modified nanofiber membrane to complete the removal of multiple pollutants in three limited treatment steps, including heavy metal ions, total phosphorus, total nitrogen, ammonia nitrogen and organic pollutants.

[0013] Resin adsorption technology is common in wastewater treatment. However, conventional resins have high material sensitivity and poor adaptability to wastewater of different compositions. In addition, resins have certain requirements for wastewater entering the resin system, that is, there are thresholds for some pollutants. If the threshold is exceeded, resin adsorption cannot be used to obtain a stable purification effect. This application uses German LANXESS: MonoPlus S100 and MonoPlus MP500 are connected in series. The former can cooperate with the effluent treated with modified nanofiber membrane to meet the resin threshold requirements, thereby avoiding the addition of additional processes before the sewage enters the resin; after treatment with cation exchange resin, the concentrations of total nitrogen, ammonia nitrogen, suspended solids and chemical oxygen demand in the sewage are significantly reduced, which just meets the treatment threshold requirements of anion exchange resin, and then the anion exchange resin is used to further adsorb phosphate, total phosphorus, fluoride, etc. to reduce the concentration of pollutants, while avoiding the pretreatment of anion exchange resin and the blockage of resin.

[0014] The specific plan is as follows:

[0015] A method for treating photovoltaic aluminum profile anodizing wastewater, comprising the following steps:

[0016] S1, filtering the photovoltaic aluminum profile anodizing wastewater through a grid to obtain raw water;

[0017] S2, passing the raw water into an electrospinning tank, wherein the electrospinning tank uses a modified nanofiber membrane as a filter material, filtering the raw water, and collecting the filtrate for the next step; the preparation method of the modified nanofiber membrane is: dispersing polylactic acid in a solvent to obtain a dispersion, adding vanadium carbide to the dispersion, stirring evenly to obtain a spinning solution, adding the spinning solution to an electrospinning device for electrospinning, and obtaining a modified nanofiber membrane;

[0018] S3, sending the filtrate to a cation exchange resin device for adsorption treatment, the cation exchange resin device is made of German LANXESS MonoPlus S100 was used as the filter material, and the effluent was collected after adsorption treatment for the next step;

[0019] S4, sending the effluent to an anion exchange resin device for adsorption treatment, the cation exchange resin device is made of German LANXESS MonoPlus MP500 is the filter material, and the effluent after adsorption treatment is reused or discharged as reclaimed water.

[0020] Furthermore, the composition of the raw water described in S1 includes: nickel 1-10 mg / L, tin 1-10 mg / L, aluminum 1-10 mg / L, phosphate 1-10 mg / L, total phosphorus 1-10 mg / L, total nitrogen 10-30 mg / L, ammonia nitrogen 1-30 mg / L, suspended matter 10-30 mg / L, fluoride 1-10 mg / L, and the chemical oxygen demand concentration is 10-50CODcr.

[0021] Furthermore, the solvent in S2 is a mixed solvent of dichloromethane and dimethylformamide, with a mass ratio of 2-3: 1. The mixed solvent at the above ratio is easy to achieve the dissolution and uniform dispersion of polylactic acid, and at the same time, when the fiber membrane is dried, it is easy to achieve solvent volatilization at low temperature, and the drying process protects the modified fiber membrane and avoids the loss of the loaded vanadium carbide particles.

[0022] Further, the amount of vanadium carbide added in S2 is 7-15% of the total weight of the polylactic acid in the dispersion. Under the above conditions, it is beneficial to obtain a better metal ion removal effect, and has a synchronous removal effect on nickel and tin, while helping to maintain the mechanical properties of the material. Conventional polylactic acid electrospun fibers do not have a synchronous removal effect on nickel and tin, so the present application uses vanadium carbide to modify the polylactic acid electrospun fibers.

[0023] Furthermore, the electrospinning voltage of S2 is 10-15KV, the jet flow rate is 1.0-3.0ml / h, and the receiving distance is 10-15cm. By controlling the spinning process under the above conditions, a nanofiber membrane with stable quality can be obtained, and the product yield exceeds 98.0%.

[0024] Furthermore, the filtrate in S2 after the nanofiber membrane treatment contains 0.1-1 mg / L nickel, 0.1-1 mg / L tin, and 0.1-1 mg / L aluminum.

[0025] Further, the total flow rate of the cation exchange resin device in S3 is (2-6)*10 -2 m / s.

[0026] Furthermore, under the above flow rate control conditions, the cationic resin has a better removal effect on total nitrogen and ammonia nitrogen. The effluent in S3 contains 1-5 mg / L of total nitrogen and 1-5 mg / L of ammonia nitrogen.

[0027] Further, the total flow rate of the cation exchange resin device in S4 is (2-6)*10 -2 m / s.

[0028] Furthermore, under the above-mentioned flow rate control conditions, the anion resin has a better removal effect on total phosphorus, phosphate and organic pollutants, and the effluent in S4 contains no more than 0.1 mg / L nickel, no more than 0.1 mg / L tin, no more than 0.1 mg / L aluminum, no more than 0.1 mg / L phosphate, no more than 0.1 mg / L total phosphorus, no more than 1 mg / L total nitrogen, no more than 1 mg / L ammonia nitrogen, no more than 1 mg / L suspended solids, no more than 1 mg / L fluoride, and the chemical oxygen demand concentration does not exceed 2CODcr.

[0029] Beneficial effects: The present invention uses modified nanofiber membranes to treat raw water and simultaneously removes multiple heavy metal ions such as nickel and tin, which helps to shorten the process flow and complete the treatment of multiple batches of photovoltaic aluminum profile anodizing wastewater in one day, thereby improving the treatment efficiency.

[0030] Furthermore, in view of the characteristics of total phosphorus, total nitrogen, ammonia nitrogen and organic pollutants in the wastewater after electrospinning membrane treatment, the present application adopts cationic resin and anionic resin from Germany's LANXESS for series treatment, so as to further remove pollutants and meet emission standards. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solution of the present invention, the accompanying drawings will be briefly introduced below. Obviously, the accompanying drawings in the following description only relate to some embodiments of the present invention, but are not intended to limit the present invention.

[0032] Figure 1 It is a process flow chart provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0033] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. In the examples, those without specifying specific techniques or conditions are carried out according to the techniques or conditions described in the literature in this area or according to the product specification. Those without specifying the manufacturer of reagents or instruments used are all conventional products that can be obtained commercially. In the following examples, if not clearly stated, "%" refers to weight percentage.

[0034] The test methods used below include:

[0035] The detection of pollutant content in wastewater is carried out in accordance with the "Electroplating Pollutant Emission Standard" GB21900-2008 and the "Comprehensive Wastewater Discharge Standard" GB 8978-1996.

[0036] The main raw materials used include:

[0037] Cationic resin model: Lanxess, Germany MonoPlus S100, and D116 macroporous cation exchange resins.

[0038] Anionic resin model: Lanxess, Germany MonoPlus MP500, and D301 macroporous anion exchange resin.

[0039] Example 1

[0040] Photovoltaic aluminum profile anodizing wastewater treatment method, wherein the wastewater comes from the photovoltaic aluminum profile anodizing section, and is filtered through a grid to obtain raw water, the composition of which is shown in Table 1. Caustic soda flakes are added to the raw water to adjust the pH to 7 to obtain acid-base neutralized wastewater.

[0041] Table 1 Wastewater composition analysis

[0042]

[0043] like Figure 1 As shown, the wastewater after acid-base neutralization is passed into an electrostatic spinning tank. The electrostatic spinning tank uses a modified nanofiber membrane as a filter material to filter the wastewater. In this embodiment, two identical electrostatic spinning tanks are connected in parallel to increase the wastewater treatment flux.

[0044] The amount of raw materials used for the modified nanofiber membrane is shown in Table 2, and the preparation method is as follows:

[0045] S1, dispersing polylactic acid in a mixed solvent of dichloromethane and dimethylformamide, wherein the mass ratio of dichloromethane to dimethylformamide is 2:1, to obtain a dispersion;

[0046] S2, adding vanadium carbide to the dispersion, stirring evenly, to obtain a spinning solution;

[0047] S3. Add the spinning solution into the electrospinning equipment, use the electrospinning equipment to perform spinning, select a spinning voltage of 12KV, a spray flow rate of 1.0ml / h, a receiving distance of 10cm, and use aluminum foil as a receiving plate. Dry the prepared nanofiber membrane at 50°C for 24 hours and take out the modified nanofiber membrane.

[0048] Table 2 Raw material dosage of modified nanofiber membrane

[0049]

[0050] The content of the filtrate obtained by filtration in the electrospinning tank is shown in Table 1.

[0051] As can be seen from Table 1, after the two-dimensional metal carbide electrospun nanofiber membrane is treated, the metal ion concentration in the solution is greatly reduced, but inorganic non-metallic pollutants and organic pollutants still exist.

[0052] Next, the filtrate obtained by the electrospinning tank filtration treatment is sent to the cation exchange resin device. The cation exchange resin device is equipped with pre-treated cationic resin: Lanxess, Germany MonoPlus S100, the treatment method is as follows: first use saturated salt water, take an amount equal to twice the volume of the resin to be treated, soak the resin in the salt solution for 18-20 hours, then drain the salt water, rinse with clean water, so that the discharged water is not yellow. Secondly, use 4wt% NaOH solution, the amount is the same as above, soak it in it for 2-4 hours (or wash it with a small flow rate), drain the alkali solution, and rinse the resin until the discharged water is close to neutral; finally, use 5wt% HCl solution, the amount is also the same as above, soak it for 4-8 hours, drain the acid, and rinse with clean water until it is neutral for use.

[0053] In this embodiment, the cation exchange resin device uses two identical cation exchange resin devices connected in parallel, and the total flow rate of the wastewater in the cation exchange resin device is: 4*10 -2 m / s, and then the wastewater after resin adsorption was discharged and its composition was analyzed, see Table 1.

[0054] As can be seen from Table 1, the electrospun nanofiber membrane combined with two-dimensional metal carbides has reduced the content of each component of the sewage to the threshold that can be treated by the cationic resin. After entering the cationic exchange resin device, the total nitrogen and ammonia nitrogen in the sewage are significantly reduced after adsorption treatment by the cationic resin; at the same time, no blockage of the cationic exchange resin device is observed.

[0055] In order to further reduce the concentrations of phosphate, total phosphorus, fluoride and chemical oxygen demand, the wastewater treated by cation exchange resin adsorption is sent to an anion exchange resin device. In this embodiment, the anion exchange resin device uses two identical anion exchange resin devices in parallel. The anion exchange resin is from Lanxess, Germany. MonoPlus MP500 is pre-treated in advance. The treatment method is as follows: first, use saturated salt water, which is about twice the volume of the resin to be treated, and soak the resin in the salt solution for 18-20 hours, then drain the salt water and rinse with clean water to make the discharged water non-yellow. Then soak it in 5wt% HCl for 4-8 hours, then drain the acid and wash it with water until it is neutral; then soak it in 4wt% NaOH solution for 4-8 hours, drain the alkali solution, and wash it with clean water until it is neutral for use.

[0056] The total flow rate of wastewater in the anion exchange resin device is: 4*10 -2 m / s, and then the wastewater after resin adsorption was discharged and its composition was analyzed, see Table 1.

[0057] As can be seen from Table 1, the values ​​of phosphate, total phosphorus, fluoride, and chemical oxygen demand are all reduced, indicating that the anion exchange resin has a further removal effect on the above pollutants, and at the same time, the anion exchange resin device is not blocked.

[0058] This embodiment uses anion and cation resins in conjunction with two-dimensional metal carbide electrospun fiber membranes, which has a good effect on sewage treatment. It not only has a good effect on heavy metal ions, but also has a good treatment effect on other pollutants in sewage. Specifically, the sewage treated with the two-dimensional metal carbide electrospun fiber membrane can reduce the pollutants in each part of the sewage to the threshold that can be treated with anion and cation resins, thereby avoiding the problem of anion and cation resins failing during use. Moreover, the sewage treated by the two achieves a higher purity effect, indicating that the fiber membrane and resin have a good effect in treating sewage.

[0059] Example 2

[0060] A method for treating photovoltaic aluminum profile anodizing wastewater, wherein the wastewater comes from the photovoltaic aluminum profile anodizing section, and is filtered through a grid to obtain raw water, and the composition is the same as in Example 1.

[0061] Add caustic soda flakes to the raw water to adjust the pH to 7 to obtain acid-base neutralized wastewater. Pass the acid-base neutralized wastewater into an electrospinning tank. The electrospinning tank uses a modified nanofiber membrane as a filter material to filter the wastewater. In this embodiment, two identical electrospinning tanks are connected in parallel to increase the wastewater treatment flux.

[0062] The preparation method of the modified nanofiber membrane is as follows:

[0063] S1, dispersing polylactic acid in a mixed solvent of dichloromethane and dimethylformamide, wherein the mass ratio of dichloromethane to dimethylformamide is 3:1, to obtain a dispersion;

[0064] S2, adding vanadium carbide to the dispersion, wherein the amount of vanadium carbide added is 10% of the total weight of the polylactic acid in the dispersion, and stirring evenly to obtain a spinning solution;

[0065] S3. Add the spinning solution into the electrospinning equipment, use the electrospinning equipment to perform spinning, select a spinning voltage of 13KV, a spray flow rate of 1.0ml / h, a receiving distance of 12cm, use aluminum foil as a receiving plate, dry the prepared nanofiber membrane at 50°C for 24 hours, and take out to obtain a modified nanofiber membrane.

[0066] Next, the filtrate obtained by the electrospinning tank filtration treatment is sent to the cation exchange resin device. The cation exchange resin device is equipped with pre-treated cationic resin from Lanxess, Germany. MonoPlus S100, the processing method is the same as in Example 1.

[0067] In this embodiment, the cation exchange resin device uses two identical cation exchange resin devices connected in parallel, and the total flow rate of the wastewater in the cation exchange resin device is: 5*10 -2 m / s.

[0068] Finally, the wastewater treated by the cation exchange resin adsorption is sent to the anion exchange resin device. In this embodiment, the anion exchange resin device uses two identical anion exchange resin devices in parallel. The anion exchange resin is from Lanxess, Germany. MonoPlus MP500 was pre-treated in advance, and the treatment method was the same as in Example 1. The total flow rate of the wastewater in the anion exchange resin device was: 5*10 -2 m / s, and then the wastewater after resin adsorption was discharged and its composition was analyzed, see Table 3.

[0069] Example 3

[0070] A method for treating photovoltaic aluminum profile anodizing wastewater, wherein the wastewater comes from the photovoltaic aluminum profile anodizing section, and is filtered through a grid to obtain raw water, and the composition is the same as in Example 1.

[0071] Add caustic soda flakes to the raw water to adjust the pH to 7 to obtain acid-base neutralized wastewater. Pass the acid-base neutralized wastewater into an electrospinning tank. The electrospinning tank uses a modified nanofiber membrane as a filter material to filter the wastewater. In this embodiment, two identical electrospinning tanks are connected in parallel to increase the wastewater treatment flux.

[0072] The preparation method of the modified nanofiber membrane is as follows:

[0073] S1, dispersing polylactic acid in a mixed solvent of dichloromethane and dimethylformamide, wherein the mass ratio of dichloromethane to dimethylformamide is 3:1, to obtain a dispersion;

[0074] S2, adding vanadium carbide to the dispersion, wherein the amount of vanadium carbide added is 12% of the total weight of the polylactic acid in the dispersion, and stirring evenly to obtain a spinning solution;

[0075] S3. Add the spinning solution into the electrospinning equipment, use the electrospinning equipment to perform spinning, select a spinning voltage of 13KV, a spray flow rate of 1.0ml / h, a receiving distance of 12cm, use aluminum foil as a receiving plate, dry the prepared nanofiber membrane at 50°C for 24 hours, and take out to obtain a modified nanofiber membrane.

[0076] Next, the filtrate obtained by the electrospinning tank filtration treatment is sent to the cation exchange resin device. The cation exchange resin device is equipped with pre-treated cationic resin from Lanxess, Germany. MonoPlus S100, the processing method is the same as in Example 1.

[0077] In this embodiment, the cation exchange resin device uses two identical cation exchange resin devices connected in parallel, and the total flow rate of the wastewater in the cation exchange resin device is: 5*10 -2 m / s.

[0078] Finally, the wastewater treated by the cation exchange resin adsorption is sent to the anion exchange resin device. In this embodiment, the anion exchange resin device uses two identical anion exchange resin devices in parallel. The anion exchange resin is from Lanxess, Germany. MonoPlus MP500 was pre-treated in advance, and the treatment method was the same as in Example 1. The total flow rate of the wastewater in the anion exchange resin device was: 5*10 -2 m / s, and then the wastewater after resin adsorption was discharged and its composition was analyzed, see Table 3.

[0079] Example 4

[0080] A method for treating photovoltaic aluminum profile anodizing wastewater, wherein the wastewater comes from the photovoltaic aluminum profile anodizing section, and is filtered through a grid to obtain raw water, and the composition is the same as in Example 1.

[0081] Add caustic soda flakes to the raw water to adjust the pH to 7 to obtain acid-base neutralized wastewater. Pass the acid-base neutralized wastewater into an electrospinning tank. The electrospinning tank uses a modified nanofiber membrane as a filter material to filter the wastewater. In this embodiment, two identical electrospinning tanks are connected in parallel to increase the wastewater treatment flux.

[0082] The preparation method of the modified nanofiber membrane is as follows:

[0083] S1, dispersing polylactic acid in a mixed solvent of dichloromethane and dimethylformamide, wherein the mass ratio of dichloromethane to dimethylformamide is 3:1, to obtain a dispersion;

[0084] S2, adding vanadium carbide to the dispersion, wherein the amount of vanadium carbide added is 10% of the total weight of the polylactic acid in the dispersion, and stirring evenly to obtain a spinning solution;

[0085] S3. Add the spinning solution into the electrospinning equipment, use the electrospinning equipment to perform spinning, select a spinning voltage of 10KV, a spray flow rate of 2.0ml / h, a receiving distance of 12cm, and use aluminum foil as a receiving plate. Dry the prepared nanofiber membrane at 50°C for 24 hours and take out to obtain a modified nanofiber membrane.

[0086] Next, the filtrate obtained by the electrospinning tank filtration treatment is sent to the cation exchange resin device. The cation exchange resin device is equipped with pre-treated cationic resin from Lanxess, Germany. MonoPlus S100, the processing method is the same as in Example 1.

[0087] In this embodiment, the cation exchange resin device uses two identical cation exchange resin devices connected in parallel, and the total flow rate of the wastewater in the cation exchange resin device is: 5*10 -2 m / s.

[0088] Finally, the wastewater treated by the cation exchange resin adsorption is sent to the anion exchange resin device. In this embodiment, the anion exchange resin device uses two identical anion exchange resin devices in parallel. The anion exchange resin is from Lanxess, Germany. MonoPlus MP500 was pre-treated in advance, and the treatment method was the same as in Example 1. The total flow rate of the wastewater in the anion exchange resin device was: 5*10 -2 m / s, and then the wastewater after resin adsorption was discharged and its composition was analyzed, see Table 3.

[0089] Example 5

[0090] A method for treating photovoltaic aluminum profile anodizing wastewater, wherein the wastewater comes from the photovoltaic aluminum profile anodizing section, and is filtered through a grid to obtain raw water, and the composition is the same as in Example 1.

[0091] Add caustic soda flakes to the raw water to adjust the pH to 7 to obtain acid-base neutralized wastewater. Pass the acid-base neutralized wastewater into an electrospinning tank. The electrospinning tank uses a modified nanofiber membrane as a filter material to filter the wastewater. In this embodiment, two identical electrospinning tanks are connected in parallel to increase the wastewater treatment flux.

[0092] The preparation method of the modified nanofiber membrane is as follows:

[0093] S1, dispersing polylactic acid in a mixed solvent of dichloromethane and dimethylformamide, wherein the mass ratio of dichloromethane to dimethylformamide is 3:1, to obtain a dispersion;

[0094] S2, adding vanadium carbide to the dispersion, wherein the amount of vanadium carbide added is 10% of the total weight of the polylactic acid in the dispersion, and stirring evenly to obtain a spinning solution;

[0095] S3. Add the spinning solution into the electrospinning equipment, use the electrospinning equipment to perform spinning, select a spinning voltage of 13KV, a spray flow rate of 1.0ml / h, a receiving distance of 12cm, use aluminum foil as a receiving plate, dry the prepared nanofiber membrane at 50°C for 24 hours, and take out to obtain a modified nanofiber membrane.

[0096] Next, the filtrate obtained by the electrospinning tank filtration treatment is sent to the cation exchange resin device. The cation exchange resin device is equipped with pre-treated cationic resin from Lanxess, Germany. MonoPlus S100, the processing method is the same as in Example 1.

[0097] In this embodiment, the cation exchange resin device uses two identical cation exchange resin devices connected in parallel, and the total flow rate of the wastewater in the cation exchange resin device is: 6*10 -2 m / s.

[0098] Finally, the wastewater treated by the cation exchange resin adsorption is sent to the anion exchange resin device. In this embodiment, the anion exchange resin device uses two identical anion exchange resin devices in parallel. The anion exchange resin is from Lanxess, Germany. MonoPlus MP500 was pre-treated in advance, and the treatment method was the same as in Example 1. The total flow rate of the wastewater in the anion exchange resin device was: 6*10 -2 m / s, and then the wastewater after resin adsorption was discharged and its composition was analyzed, see Table 3.

[0099] Table 3 Wastewater treatment effect table of Example 2-5

[0100]

[0101]

[0102] Comparative Example 1

[0103] Referring to Example 1, conventional cationic resin D116 macroporous cationic exchange resin was used to replace the cationic exchange resin in Example 1. Other methods were the same as those in Example 1. The raw water was treated as follows:

[0104] Add caustic soda flakes to the raw water to adjust the pH to 7 to obtain acid-base neutralized wastewater. Pass the acid-base neutralized wastewater into an electrospinning tank. The electrospinning tank uses a modified nanofiber membrane (same as in Example 1) as a filter material to filter the wastewater. Two identical electrospinning tanks in parallel are used to increase the wastewater treatment flux.

[0105] Next, the filtrate obtained by the electrospinning tank filtration treatment is sent to the cation exchange resin device. The cation exchange resin device is equipped with a pre-treated cation resin, which is a D116 macroporous cation exchange resin, and is pre-treated using a conventional resin activation method. The cation exchange resin device uses two identical cation exchange resin devices in parallel. The total flow rate of the wastewater in the cation exchange resin device is: 4*10 -2 m / s, and then the wastewater adsorbed by the resin is discharged.

[0106] In order to further reduce the pollutant content, the wastewater treated by cation exchange resin adsorption is sent to the anion exchange resin device. The anion exchange resin device uses two identical anion exchange resin devices in parallel. The anion exchange resin is from Lanxess, Germany. MonoPlus MP500 was pre-treated in advance, referring to Example 1. The total flow rate of wastewater in the anion exchange resin device is: 4*10 -2 m / s, and then the wastewater adsorbed by the resin is discharged. The results are shown in the table below.

[0107] Table 4 Comparative Example 1 Wastewater Treatment Effect Table

[0108]

[0109]

[0110] It can be seen from the above table that after replacing with conventional cationic resin, the device has the ability to remove metal ions, but the removal capacity for phosphate, total phosphorus and total nitrogen is significantly reduced, so the final water quality after treatment does not meet the primary emission standards.

[0111] Comparative Example 2

[0112] Referring to Example 1, conventional anion resin D301 macroporous anion exchange resin was used to replace the anion exchange resin in Example 1. Other methods were the same as those in Example 1. The raw water was treated as follows:

[0113] Add caustic soda flakes to the raw water to adjust the pH to 7 to obtain acid-base neutralized wastewater. Pass the acid-base neutralized wastewater into an electrospinning tank. The electrospinning tank uses a modified nanofiber membrane (same as in Example 1) as a filter material to filter the wastewater. Two identical electrospinning tanks in parallel are used to increase the wastewater treatment flux.

[0114] Next, the filtrate obtained by the electrospinning tank filtration treatment is sent to the cation exchange resin device. The cation exchange resin device is equipped with pre-treated cation resin, which is from Lanxess, Germany. MonoPlus S100, the pre-treatment method is the same as in Example 1. The cation exchange resin device uses two identical cation exchange resin devices in parallel, and the total flow rate of the wastewater in the cation exchange resin device is: 4*10 -2 m / s, and then the wastewater adsorbed by the resin is discharged.

[0115] In order to further reduce the pollutant content, the wastewater treated by cation exchange resin adsorption is sent to the anion exchange resin device. The anion exchange resin device uses two identical anion exchange resin devices in parallel. The anion exchange resin is D301 macroporous anion exchange resin, which is pretreated in advance by conventional resin activation. The total flow rate of wastewater in the anion exchange resin device is: 4*10 -2 m / s, and then the wastewater adsorbed by the resin is discharged. The results are shown in the table below.

[0116] Table 5 Comparative Example 2 Wastewater Treatment Effect Table

[0117]

[0118] From the table above, it can be found that after replacing with conventional anion resin, the device has the ability to remove metal ions, but the ability to remove phosphate and total phosphorus has decreased significantly. According to the first-level standard in Table 4 of the "Comprehensive Standard for Wastewater Discharge" GB8978-1996, the phosphate concentration must be ≤0.5mg / L. In this way, the final water quality after treatment just meets the first-level discharge standard in the phosphate project, but there is a possibility of fluctuation in the treatment effect caused by fluctuations in the raw water composition. Therefore, there is still a risk of substandard water quality when the above device is in long-term operation. At the same time, the anion exchange resin device has the phenomenon of poor liquid outflow, and there may be resin blockage.

[0119] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0120] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0121] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A method for treating photovoltaic aluminum profile anodizing wastewater, characterized in that: The following steps are involved: S1, filtering the photovoltaic aluminum profile anodizing wastewater through a grid to obtain raw water; S2, passing the raw water into an electrospinning tank, wherein the electrospinning tank uses a modified nanofiber membrane as a filter material, filters the raw water, and collects the filtrate for the next step; The preparation method of the modified nanofiber membrane is as follows: polylactic acid is dispersed in a solvent to obtain a dispersion, vanadium carbide is added to the dispersion, and the mixture is stirred evenly to obtain a spinning solution, and the spinning solution is added to an electrospinning device for electrospinning to obtain a modified nanofiber membrane; S3, sending the filtrate to a cation exchange resin device for adsorption treatment, the cation exchange resin device is made of German LANXESS MonoPlus S100 was used as the filter material, and the effluent was collected after adsorption treatment for the next step; S4, sending the effluent to an anion exchange resin device for adsorption treatment, the cation exchange resin device is made of German LANXESS MonoPlus MP500 is the filter material, and the effluent after adsorption treatment is reused or discharged as reclaimed water.

2. The photovoltaic aluminum profile anodizing wastewater treatment method according to claim 1, characterized in that: The composition of the raw water described in S1 includes: nickel 1-10 mg / L, tin 1-10 mg / L, aluminum 1-10 mg / L, phosphate 1-10 mg / L, total phosphorus 1-10 mg / L, total nitrogen 10-30 mg / L, ammonia nitrogen 1-30 mg / L, suspended matter 10-30 mg / L, fluoride 1-10 mg / L, and the chemical oxygen demand concentration is 10-50CODcr.

3. The photovoltaic aluminum profile anodizing wastewater treatment method according to claim 2, characterized in that: The solvent in S2 is a mixed solvent of dichloromethane and dimethylformamide, with a mass ratio of 2-3:

1.

4. The photovoltaic aluminum profile anodizing wastewater treatment method according to claim 3, characterized in that: The amount of vanadium carbide added in S2 is 7-15% of the total weight of the polylactic acid in the dispersion.

5. The photovoltaic aluminum profile anodizing wastewater treatment method according to claim 4, characterized in that: The electrospinning voltage of S2 is 10-15KV, the jet flow rate is 1.0-3.0ml / h, and the receiving distance is 10-15cm.

6. The photovoltaic aluminum profile anodizing wastewater treatment method according to claim 5, characterized in that: The filtrate in S2 contains 0.1-1 mg / L nickel, 0.1-1 mg / L tin, and 0.1-1 mg / L aluminum.

7. The photovoltaic aluminum profile anodizing wastewater treatment method according to any one of claims 2 to 5, characterized in that: The total flow rate of the cation exchange resin device in S3 is (2-6)*10 -2 m / s.

8. The photovoltaic aluminum profile anodizing wastewater treatment method according to claim 6, characterized in that: The effluent in S3 contains 1-5 mg / L of total nitrogen and 1-5 mg / L of ammonia nitrogen.

9. The photovoltaic aluminum profile anodizing wastewater treatment method according to claim 8, characterized in that: The total flow rate of the cation exchange resin device in S4 is (2-6)*10 -2 m / s.

10. The photovoltaic aluminum profile anodizing wastewater treatment method according to claim 9, characterized in that: The effluent described in S4 contains no more than 0.1 mg / L nickel, no more than 0.1 mg / L tin, no more than 0.1 mg / L aluminum, no more than 0.1 mg / L phosphate, no more than 0.1 mg / L total phosphorus, no more than 1 mg / L total nitrogen, no more than 1 mg / L ammonia nitrogen, no more than 1 mg / L suspended solids, no more than 1 mg / L fluoride, and the chemical oxygen demand concentration does not exceed 2CODcr.

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