Nickel-containing wastewater treatment method

Abstract

The invention relates to a nickel-containing wastewater treatment agent which comprises an adsorbent, a microbial agent, activated carbon, aluminum chloride, ferric sulfate, manganese dioxide, ferric oxide and polyacrylamide. Wherein the adsorbent is obtained by carrying out alkali modification on at least one of soybean stalks and corn stalks; the microbial agent comprises at least one or more of bacillus megatherium, achromobacter xylosoxidans and stenotrophomonas maltophilia. The nickel-containing wastewater treated by the treatment agent can meet discharge requirements, and the treatment effect of the nickel-containing wastewater can be effectively improved by adding the adsorbent and the microbial agent into the treatment agent.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater treatment, and in particular to a method for treating nickel-containing wastewater. Background Art

[0002] With the rapid development of my country's industrial industry, a large amount of industrial wastewater generated in the production process is discharged. Although people's environmental awareness has increased in recent years and national policies have intervened vigorously, the base of industrial wastewater discharge is still very large. Industrial wastewater contains excessively high concentrations of heavy metals, such as nickel, chromium, zinc, copper, lead, etc. These heavy metals cannot be biodegraded. If they are not effectively treated, on the one hand, they will be enriched through the food chain and eventually absorbed by humans, causing great harm to human health, and on the other hand, they will damage the water environment and the entire ecosystem.

[0003] Among many heavy metals, nickel, as a transition metal, is widely used in industrial production processes for its wear resistance and corrosion resistance, and is used to produce industrial products such as instruments, medical equipment, and automotive components. Such a wide range of applications will inevitably lead to huge consumption of nickel, and such huge consumption of nickel means the discharge of a large amount of nickel-containing wastewater. Therefore, it is urgent to research and develop efficient and low-cost nickel-containing wastewater treatment technology. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, the present invention provides a method for treating nickel-containing wastewater, which can effectively solve the above-mentioned problems of the prior art.

[0005] Technical Solution

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0007] The present invention provides a nickel-containing wastewater treatment agent, which comprises: an adsorbent, a microbial agent, activated carbon, aluminum chloride, ferric sulfate, manganese dioxide, ferric oxide and polyacrylamide; wherein the adsorbent is obtained by alkali-modifying at least one of soybean stalks and corn stalks;

[0008] The microbial agent includes at least one or more of Bacillus megaterium, Achromobacter xylosoxidans and Stenotrophomonas maltophilia.

[0009] Furthermore, it includes, by weight: 150-200 parts of adsorbent, 80-120 parts of microbial agent, 20-35 parts of activated carbon, 10-20 parts of aluminum chloride, 10-20 parts of iron sulfate, 8-16 parts of manganese dioxide, 5-15 parts of iron oxide, and 10-15 parts of polyacrylamide.

[0010] Preferably, in parts by weight, it includes: 180 parts of adsorbent, 100 parts of microbial agent, 28 parts of activated carbon, 15 parts of aluminum chloride, 15 parts of iron sulfate, 12 parts of manganese dioxide, 10 parts of iron oxide, and 12 parts of polyacrylamide.

[0011] Furthermore, the adsorbent is prepared by subjecting a mixture of soybean stalks and corn stalks to alkali treatment, and the weight ratio of the soybean stalks to the corn stalks is 2-6:1.

[0012] Furthermore, the microbial agent includes Bacillus megaterium, Achromobacter xylosoxidans and Stenotrophomonas maltophilia, and the weight ratio of Bacillus megaterium, Achromobacter xylosoxidans and Stenotrophomonas maltophilia is 1:2:1.

[0013] Furthermore, the preparation method of the adsorbent is as follows:

[0014] (1) drying a mixture of soybean stalks and corn stalks, crushing and grinding the mixture, selecting particles with a size of 40-70 mesh, and drying the mixture at 50-70° C. for 2-5 hours;

[0015] (2) preparing sodium hydroxide and water to a concentration of 0.1-0.5 mol / L;

[0016] (3) At room temperature, 400-600 ml of the alkaline solution of step (2) and 20-40 g of the mixture obtained in step (1) are uniformly mixed and stirred for 1-3 h; the modified solid-liquid mixture is then placed in a desktop high-speed centrifuge and centrifuged for 1-5 min, and the separated solid sample is placed on filter paper and washed with deionized water until the pH value of the filtrate remains substantially unchanged, and the solid sample is collected and placed in a 90-120° C. oven for drying for 5-18 h and then stored for later use.

[0017] A method for treating nickel-containing wastewater, which uses the above-mentioned treating agent to treat the nickel-containing wastewater.

[0018] Further, the processing steps are as follows:

[0019] (1) filtering the wastewater to separate solid particles and insoluble residues in the wastewater from the waste liquid to obtain a supernatant and a precipitate;

[0020] (2) adding alkali solution to the supernatant obtained in step (1) to neutralize the wastewater to a pH of 6-7, and then adding a treatment agent in an amount of 0.3-1.4 kg / t, and then stirring and mixing for 10-12 hours, and then letting it stand for 24 hours and filtering to obtain a supernatant and a precipitate;

[0021] (3) filtering the supernatant in step (2) through an ultrafiltration membrane to obtain an ultrafiltration concentrate and an ultrafiltration permeate; the ultrafiltration concentrate can be returned to step (2);

[0022] (4) filtering the ultrafiltration permeate through a reverse osmosis membrane to obtain a reverse osmosis concentrate and a reverse osmosis filtrate; the reverse osmosis concentrate can be returned to step (2).

[0023] Beneficial Effects

[0024] The technical solution provided by the present invention has the following beneficial effects compared with the known public technology: nickel-containing wastewater treated by the treatment agent of the present invention can meet the discharge requirements; when the treatment agent lacks adsorbent or microbial agent, the wastewater treatment effect is poor, and at the same time, when and only when the microbial agent contains Bacillus megaterium, Achromobacter xylosoxidans and Stenotrophomonas maltophilia at the same time, the wastewater treatment effect is the best. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] The present invention will be further described below in conjunction with the embodiments.

[0027] (I) Embodiment

[0028] Embodiment 1:

[0029] A nickel-containing wastewater treatment agent comprises, by weight: 180 parts of adsorbent, 100 parts of microbial agents, 28 parts of activated carbon, 15 parts of aluminum chloride, 15 parts of ferric sulfate, 12 parts of manganese dioxide, 10 parts of iron oxide, and 12 parts of polyacrylamide.

[0030] The microbial agent includes Bacillus megaterium, Achromobacter xylosoxidans and Stenotrophomonas maltophilia, and the weight ratio of Bacillus megaterium, Achromobacter xylosoxidans and Stenotrophomonas maltophilia is 1:2:1.

[0031] The preparation method of the adsorbent is as follows:

[0032] (1) Soybean stalks and corn stalks were mixed in a weight ratio of 4:1, dried at 60°C for 12 h, crushed and ground, and the particles with a size of 40-70 mesh were screened, and then dried at 60°C for 4 h;

[0033] (2) preparing sodium hydroxide and water to a concentration of 0.3 mol / L;

[0034] (3) At room temperature, 500 ml of the alkaline solution in step (2) and 25 g of the mixture obtained in step (1) were uniformly mixed and stirred for 2.5 h; the modified solid-liquid mixture was then centrifuged in a desktop high-speed centrifuge at 2000 rpm for 3 min, and the separated solid sample was placed on filter paper and washed with deionized water until the pH value of the filtrate remained substantially unchanged, and the solid sample was collected and placed in an oven at 105° C. for drying for 12 h and then stored for later use.

[0035] Comparative Example 1:

[0036] The only difference from Example 1 is that no adsorbent is added;

[0037] Comparative Example 2:

[0038] The only difference from Example 1 is that no microbial agent is added;

[0039] Comparative Example 3:

[0040] The only difference from Example 1 is that the microbial agent only includes Bacillus megaterium;

[0041] Comparative Example 4:

[0042] The only difference from Example 1 is that the microbial agent only includes Achromobacter xylosoxidans;

[0043] Comparative Example 5:

[0044] The only difference from Example 1 is that the microbial agent only includes Stenotrophomonas maltophilia;

[0045] The microbial agents in Example 1 and Comparative Examples 1-5 are as follows:

[0046] Bacillus megaterium KBme-11 was deposited in China Center for Type Culture Collection (CCTCC) on June 7, 2022, with the deposit number CCTCC NO: M2022822, and the deposit address is Wuhan University, Wuhan, China;

[0047] Achromobacter xylosoxidans HL-3 was deposited at the General Microbiology Center of China Culture Collection Administration on May 23, 2023, with the deposit number CGMCC No. 27444, and the deposit address is No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing.

[0048] Stenotrophomonas maltophilia HL-20 was deposited at the General Microbiology Center of China Culture Collection Administration on May 23, 2023, with the deposit number CGMCC No. 27449, and the deposit address is No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing.

[0049] The effective viable counts of Bacillus megaterium, Achromobacter xylosoxidans and Stenotrophomonas maltophilia were all 2.5 billion / g.

[0050] (II) Treatment of nickel-containing wastewater

[0051] (1) The physical and chemical parameters of nickel-containing wastewater are as follows:

[0052] index Numeric COD 4500mg / L Ammonia nitrogen 600mg / L Total Nickel 1600mg / L Total Nitrogen 700mg / L

[0053] (2) The above nickel-containing wastewater was treated with the treatment agents prepared in Example 1 and Comparative Examples 1-5, respectively, and the specific treatment steps were as follows:

[0054] S1: filtering the wastewater to separate the solid particles and insoluble residues in the wastewater from the waste liquid to obtain a supernatant and a precipitate;

[0055] S2: adding sodium hydroxide to the supernatant obtained in step S1 to neutralize the wastewater to a pH of 8-9, and then adding a treatment agent in an amount of 0.95 kg / t, and then stirring and mixing for 12 hours, and then letting it stand for 24 hours and filtering to obtain a supernatant and a precipitate;

[0056] S3: filtering the supernatant in step S2 through an ultrafiltration membrane to obtain an ultrafiltration concentrate and an ultrafiltration permeate;

[0057] S4: filtering the ultrafiltration liquid through a reverse osmosis membrane to obtain a reverse osmosis concentrate and a reverse osmosis filtrate;

[0058] Among them, the ultrafiltration membranes all use 100KD 2540 wide flow channel roll membranes, model: Zhongke Ruiyang SG-UE100-2540-G2;

[0059] Reverse osmosis uses 0.5nm RO membrane, model: Dow BW30-2540;

[0060] (3) The main indicators of nickel-containing wastewater treated with the treatment agent prepared by Example 1 and Comparative Examples 1-5 are as follows:

[0061]

[0062] It can be seen from the embodiments that nickel-containing wastewater treated with the treatment agent of the present invention can meet the discharge requirements; it can be seen from the comparative examples that when the treatment agent lacks adsorbent or microbial agent, the wastewater treatment effect is poor, and the wastewater treatment effect is best when and only when the microbial agent contains Bacillus megaterium, Achromobacter xylosoxidans and Stenotrophomonas maltophilia at the same time.

[0063] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. A nickel-containing wastewater treatment agent, characterized in that It includes: Adsorbent, microbial agent, activated carbon, aluminum chloride, ferric sulfate, manganese dioxide, iron oxide and polyacrylamide; wherein the adsorbent is obtained by alkali-modifying at least one of soybean stalks and corn stalks; The microbial agent includes at least one or more of Bacillus megaterium, Achromobacter xylosoxidans and Stenotrophomonas maltophilia.

2. A nickel-containing wastewater treatment agent according to claim 1, characterized in that: In parts by weight, it includes: 150-200 parts of adsorbent, 80-120 parts of microbial agent, 20-35 parts of activated carbon, 10-20 parts of aluminum chloride, 10-20 parts of iron sulfate, 8-16 parts of manganese dioxide, 5-15 parts of iron oxide, and 10-15 parts of polyacrylamide.

3. A nickel-containing wastewater treatment agent according to claim 1, characterized in that: The adsorbent is prepared by subjecting a mixture of soybean stalks and corn stalks to alkali treatment, and the weight ratio of the soybean stalks to the corn stalks is 2-6:

1.

4. A nickel-containing wastewater treatment agent according to claim 1, characterized in that: The microbial agent comprises Bacillus megaterium, Achromobacter xylosoxidans and Stenotrophomonas maltophilia, and the weight ratio of Bacillus megaterium, Achromobacter xylosoxidans and Stenotrophomonas maltophilia is 1:2:

1.

5. A method for treating nickel-containing wastewater, characterized in that: The method uses the treating agent described in any one of claims 1 to 4 to treat nickel-containing wastewater.

6. A method for treating nickel-containing wastewater according to claim 5, characterized in that: The processing steps are as follows: (1) filtering the wastewater to separate solid particles and insoluble residues in the wastewater from the waste liquid to obtain a supernatant and a precipitate; (2) adding alkali solution to the supernatant obtained in step (1) to neutralize the wastewater to a pH of 8-9, and then adding a treatment agent in an amount of 0.3-1.4 kg / t, and then stirring and mixing for 10-12 hours, and then letting it stand for 24 hours and filtering to obtain a supernatant and a precipitate; (3) filtering the supernatant in step (2) through an ultrafiltration membrane to obtain an ultrafiltration concentrate and an ultrafiltration permeate; (4) The ultrafiltration liquid is filtered through a reverse osmosis membrane.

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