Industrial wastewater treatment method based on infrared spectrum detection technology

Abstract

The invention belongs to the technical field of water treatment, and discloses an industrial wastewater treatment method based on an infrared spectrum detection technology. The treatment object of the invention is industrial wastewater containing heavy metals, and the heavy metals comprise manganese, mercury and chromium. According to the method disclosed by the invention, the industrial wastewater treated by a series of steps of coagulation, aeration, catalytic oxidation, biological flocculation, filtration, infrared spectrum monitoring and the like can realize simultaneous standard reaching of heavy metals and COD (Chemical Oxygen Demand). The method provided by the invention has high treatment efficiency, and is energy-saving and environment-friendly.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater treatment, and in particular to an industrial wastewater treatment method based on infrared spectrum detection technology. Background Art

[0002] Industrial wastewater includes production wastewater, production sewage and cooling water. It refers to wastewater and waste liquid generated in the industrial production process, which contains industrial production materials, intermediate products, by-products and pollutants generated in the production process that are lost with water. There are many types of industrial wastewater with complex components. For example, electrolytic salt industrial wastewater contains mercury, heavy metal smelting industrial wastewater contains lead, cadmium and other metals, electroplating industrial wastewater contains cyanide and chromium and other heavy metals, petroleum refining industrial wastewater contains phenol, pesticide manufacturing industrial wastewater contains various pesticides, etc.

[0003] According to the chemical properties of the main pollutants contained in industrial wastewater, inorganic wastewater mainly contains inorganic pollutants, and organic wastewater mainly contains organic pollutants. For example, electroplating wastewater and wastewater from mineral processing are inorganic wastewater, wastewater from food or petroleum processing is organic wastewater, and wastewater from the printing and dyeing industry is mixed wastewater. The components of wastewater discharged from different industries are different. Heavy metal wastewater mainly comes from wastewater discharged by mining, smelting, electrolysis, electroplating, pesticides, medicines, paints, pigments and other enterprises. The types, contents and forms of heavy metals in wastewater vary from production enterprise to production enterprise. Because heavy metals cannot be decomposed and destroyed, they can only be transferred to other locations and their physical and chemical forms.

[0004] Since industrial wastewater often contains a variety of toxic substances, polluting the environment is very harmful to human health. Therefore, it is necessary to develop comprehensive utilization, turn harm into benefit, and take appropriate purification measures according to the composition and concentration of pollutants in the wastewater before it can be discharged. Summary of the invention

[0005] Purpose of the invention: In view of the shortcomings of the prior art, the present invention provides a method for treating industrial wastewater based on infrared spectroscopy detection technology, especially industrial wastewater containing heavy metals.

[0006] Technical solution: The present invention provides an industrial wastewater treatment method based on infrared spectroscopy detection technology, comprising the following steps:

[0007] Step 1: Coagulation:

[0008] Sodium carbonate is added to industrial wastewater containing heavy metals to adjust the pH value to 8, and a coagulant is added. The coagulant is a cationic inorganic polymer flocculant, and the amount of the coagulant added is until no precipitation is generated.

[0009] Step 2 Aeration:

[0010] Jet aeration is used, the oxygen flow rate of aeration is 0.2-0.3L / min, the aeration time is 6-8h, and the aeration is allowed to settle for 6-8h after the aeration is completed.

[0011] Step 3: Catalytic oxidation:

[0012] The supernatant obtained after precipitation in step 2 is introduced into a catalytic oxidation reaction tank, and a catalyst is added to the reaction tank, wherein the catalyst is a transition metal-loaded catalyst; the amount of the catalyst added is 100-300 mg / L, and jet aeration is adopted, the aeration oxygen flow rate is 0.2-0.3 L / min, and the aeration time is 2-5 h.

[0013] Step 4 Bioflocculation:

[0014] The sewage treated in step 3 is sent to the flocculation tank, and a biological flocculant is added to the flocculation tank. The biological flocculant is activated sludge, and the addition amount is 100-300mL / L. A micro-nano bubble generator is used for aeration, the oxygen flow rate is 0.1-0.2L / min, the reaction time is 8-10h, and the sedimentation is allowed to stand for 3-5h.

[0015] Step 5 Filter:

[0016] Sodium hypochlorite is added to the sewage treated in step 4, the dosage of which is 10-20 mmol / L, and then the sewage is sent to a filtration system, and the pH is adjusted to neutral to obtain treated wastewater.

[0017] Step 6 Monitoring:

[0018] Randomly collect samples of the wastewater treated in step 5, and use an infrared spectrometer to in-situ detect the composition and content of pollutants in the wastewater. If it does not meet the emission standards, drain it to the reaction tank and repeat the above steps.

[0019] Specifically, the coagulant described in step 1 is polymerized aluminum oxide.

[0020] Specifically, the catalyst in step 3 is a nickel-supported molecular sieve catalyst, wherein the nickel content of the nickel-supported molecular sieve catalyst is 15-20%.

[0021] Specifically, the catalyst in step 3 is a zinc-supported molecular sieve catalyst. The catalyst is a zinc-supported molecular sieve catalyst with a zinc content of 10-15%.

[0022] Specifically, the bioflocculant in step 4 is a bioflocculant produced by Paecilomyces 1-1.

[0023] Specifically, the industrial wastewater described in the present invention contains manganese, mercury and chromium.

[0024] Beneficial effects: The treatment method provided by the present invention can achieve high efficiency in treating industrial wastewater containing heavy metals by using processes such as coagulation, aeration, catalytic oxidation, and biological flocculation. The method of the present invention can achieve the simultaneous compliance of heavy metals and COD, which is more energy-saving and environmentally friendly. DETAILED DESCRIPTION

[0025] The following are embodiments to illustrate the scheme of the present invention in detail, but the protection scope of the present invention is not limited to the embodiments.

[0026] Example 1

[0027] Step 1: Coagulation:

[0028] Sodium carbonate is added to industrial wastewater containing heavy metals to adjust the pH value to 8, and a coagulant is added, wherein the coagulant is polymerized aluminum oxide, and the amount of the coagulant added is such that no precipitation is generated.

[0029] Step 2 Aeration:

[0030] Jet aeration was used with an oxygen flow rate of 0.2 L / min and an aeration time of 6 h. After aeration, the aeration was allowed to settle for 6 h.

[0031] Step 3: Catalytic oxidation:

[0032] The supernatant obtained after precipitation in step 2 is introduced into a catalytic oxidation reaction tank, and a nickel-loaded molecular sieve catalyst is added to the reaction tank, wherein the catalyst is a transition metal-loaded catalyst; the amount of catalyst added is 100 mg / L, and jet aeration is adopted, the aeration oxygen flow rate is 0.2 L / min, and the aeration time is 2 h.

[0033] Step 4 Bioflocculation:

[0034] The treated sewage in step 3 is sent to a flocculation tank, and a biological flocculant produced by Paecilomyces p. I-1 is added to the flocculation tank in an amount of 100 mL / L. A micro-nano bubble generator is used for aeration, the oxygen flow rate is 0.1 L / min, the reaction time is 8 h, and the tank is allowed to settle for 3 h.

[0035] Step 5 Filter:

[0036] Sodium hypochlorite is added to the sewage treated in step 4, the dosage of which is 10 mmol / L, and then the sewage is sent to a filtration system, the pH is adjusted to neutral, and treated wastewater is obtained.

[0037] Step 6 Monitoring:

[0038] Randomly collect samples of the wastewater treated in step 5, and use an infrared spectrometer to in-situ detect the composition and content of pollutants in the wastewater. If it does not meet the emission standards, drain it to the reaction tank and repeat the above steps.

[0039] Example 2

[0040] Step 1: Coagulation:

[0041] Sodium carbonate is added to industrial wastewater containing heavy metals to adjust the pH value to 8, and a coagulant is added, wherein the coagulant is polymerized aluminum oxide, and the amount of the coagulant added is such that no precipitation is generated.

[0042] Step 2 Aeration:

[0043] Jet aeration was used with an oxygen flow rate of 0.3 L / min and an aeration time of 8 h. After aeration, the aeration was allowed to settle for 8 h.

[0044] Step 3: Catalytic oxidation:

[0045] The supernatant obtained after precipitation in step 2 is introduced into a catalytic oxidation reaction tank, and a nickel-loaded molecular sieve catalyst is added to the reaction tank, wherein the catalyst is a transition metal-loaded catalyst; the amount of the catalyst added is 300 mg / L, and jet aeration is used, the aeration oxygen flow rate is 0.3 L / min, and the aeration time is 5 h.

[0046] Step 4 Bioflocculation:

[0047] The treated sewage in step 3 is sent to a flocculation tank, and a biological flocculant produced by Paecilomyces p. I-1 is added to the flocculation tank in an amount of 300 mL / L. A micro-nano bubble generator is used for aeration, the oxygen flow rate is 0.2 L / min, the reaction time is 10 h, and the tank is allowed to settle for 5 h.

[0048] Step 5 Filter:

[0049] Sodium hypochlorite is added to the sewage treated in step 4, the dosage of which is 20 mmol / L, and then the sewage is sent to a filtration system, the pH is adjusted to neutral, and treated wastewater is obtained.

[0050] Step 6 Monitoring:

[0051] Randomly collect samples of the wastewater treated in step 5, and use an infrared spectrometer to in-situ detect the composition and content of pollutants in the wastewater. If it does not meet the emission standards, drain it to the reaction tank and repeat the above steps.

[0052] Example 3

[0053] Step 1: Coagulation:

[0054] Sodium carbonate is added to industrial wastewater containing heavy metals to adjust the pH value to 8, and a coagulant is added, wherein the coagulant is polymerized aluminum oxide, and the amount of the coagulant added is such that no precipitation is generated.

[0055] Step 2 Aeration:

[0056] Jet aeration was used with an oxygen flow rate of 0.3 L / min and an aeration time of 8 h. After aeration, the aeration was allowed to settle for 8 h.

[0057] Step 3: Catalytic oxidation:

[0058] The supernatant obtained after precipitation in step 2 is introduced into a catalytic oxidation reaction tank, and a nickel-loaded molecular sieve catalyst is added to the reaction tank, wherein the catalyst is a transition metal-loaded catalyst; the amount of the catalyst added is 100 mg / L, and jet aeration is used, the aeration oxygen flow rate is 0.3 L / min, and the aeration time is 5 h.

[0059] Step 4 Bioflocculation:

[0060] The treated sewage in step 3 is sent to a flocculation tank, and a biological flocculant produced by Paecilomyces p. I-1 is added to the flocculation tank in an amount of 300 mL / L. A micro-nano bubble generator is used for aeration, the oxygen flow rate is 0.1 L / min, the reaction time is 10 h, and the tank is allowed to settle for 5 h.

[0061] Step 5 Filter:

[0062] Sodium hypochlorite is added to the sewage treated in step 4, the dosage of which is 10 mmol / L, and then the sewage is sent to a filtration system, the pH is adjusted to neutral, and treated wastewater is obtained.

[0063] Step 6 Monitoring:

[0064] Randomly collect samples of the wastewater treated in step 5, and use an infrared spectrometer to in-situ detect the composition and content of pollutants in the wastewater. If it does not meet the emission standards, drain it to the reaction tank and repeat the above steps.

[0065] Example 4

[0066] Step 1: Coagulation:

[0067] Sodium carbonate is added to industrial wastewater containing heavy metals to adjust the pH value to 8, and a coagulant is added, wherein the coagulant is polymerized aluminum oxide, and the amount of the coagulant added is such that no precipitation is generated.

[0068] Step 2 Aeration:

[0069] Jet aeration was used with an oxygen flow rate of 0.3 L / min and an aeration time of 8 h. After aeration, the aeration was allowed to settle for 8 h.

[0070] Step 3: Catalytic oxidation:

[0071] The supernatant obtained after precipitation in step 2 is introduced into a catalytic oxidation reaction tank, and a zinc-loaded molecular sieve catalyst is added to the reaction tank, wherein the catalyst is a transition metal-loaded catalyst; the amount of the catalyst added is 100 mg / L, and jet aeration is adopted, the aeration oxygen flow rate is 0.3 L / min, and the aeration time is 5 h.

[0072] Step 4 Bioflocculation:

[0073] The treated sewage in step 3 is sent to a flocculation tank, and a biological flocculant produced by Paecilomyces p. I-1 is added to the flocculation tank in an amount of 300 mL / L. A micro-nano bubble generator is used for aeration, the oxygen flow rate is 0.1 L / min, the reaction time is 10 h, and the tank is allowed to settle for 5 h.

[0074] Step 5 Filter:

[0075] Sodium hypochlorite is added to the sewage treated in step 4, the dosage of which is 10 mmol / L, and then the sewage is sent to a filtration system, the pH is adjusted to neutral, and treated wastewater is obtained.

[0076] Step 6 Monitoring:

[0077] Randomly collect samples of the wastewater treated in step 5, and use an infrared spectrometer to in-situ detect the composition and content of pollutants in the wastewater. If it does not meet the emission standards, drain it to the reaction tank and repeat the above steps.

[0078] The final test data of Examples 1 to 4 are shown in the following table:

[0079]

[0080] From the above test data, it can be seen that for the present invention, the treatment effect of Example 3 is the best. The industrial wastewater treated by the present invention meets the discharge standard. The above description is only a preferred embodiment of the present application and is not intended to limit the present application.

Claims

1. A method for treating industrial wastewater based on infrared spectroscopy detection technology, characterized in that: The steps include: Step 1: Coagulation: Adding sodium carbonate to industrial wastewater containing heavy metals, adjusting the pH value to 8, and adding a coagulant, wherein the coagulant is a cationic inorganic polymer flocculant, and the amount of the coagulant added is such that no precipitation is generated; Step 2 Aeration: Use jet aeration, the oxygen flow rate of aeration is 0.2-0.3L / min, the aeration time is 6-8h, and the aeration is allowed to settle for 6-8h after the aeration is completed; Step 3: Catalytic oxidation: The supernatant obtained after precipitation in step 2 is introduced into a catalytic oxidation reaction tank, and a catalyst is added to the reaction tank, wherein the catalyst is a transition metal-supported catalyst; the amount of the catalyst added is 100-300 mg / L, and jet aeration is used, the oxygen flow rate of aeration is 0.2-0.3 L / min, and the aeration time is 2-5 h; Step 4 Bioflocculation: The treated sewage in step 3 is sent to a flocculation tank, and a biological flocculant is added to the flocculation tank. The biological flocculant is activated sludge, and the addition amount is 100-300 mL / L. A micro-nano bubble generator is used for aeration, the oxygen flow rate is 0.1-0.2 L / min, the reaction time is 8-10 h, and the sedimentation is allowed to stand for 3-5 h; Step 5 Filter: The sewage treated in step 4 is added with sodium hypochlorite in an amount of 10-20 mmol / L, and then sent to a filtration system, and the pH is adjusted to neutral to obtain treated wastewater; Step 6 Monitoring: Randomly collect samples of the wastewater treated in step 5, and use an infrared spectrometer to in-situ detect the composition and content of pollutants in the wastewater. If it does not meet the emission standards, drain it to the reaction tank and repeat the above steps.

2. The method for treating industrial wastewater based on infrared spectroscopy detection technology according to claim 1, characterized in that: The coagulant described in step 1 is polymerized aluminum oxide.

3. The method for treating industrial wastewater based on infrared spectroscopy detection technology according to claim 1, characterized in that: The catalyst described in step 3 is a nickel-supported molecular sieve catalyst.

4. The method for treating industrial wastewater based on infrared spectroscopy detection technology according to claim 3, characterized in that: The nickel content of the nickel-supported molecular sieve catalyst in step 3 is 15-20%.

5. The method for treating industrial wastewater based on infrared spectroscopy detection technology according to claim 1, characterized in that: The catalyst described in step 3 is a zinc-supported molecular sieve catalyst.

6. The method for treating industrial wastewater based on infrared spectroscopy detection technology according to claim 5, characterized in that: The catalyst described in step 3 is a zinc-supported molecular sieve catalyst having a zinc content of 10-15%.

7. The method for treating industrial wastewater based on infrared spectroscopy detection technology according to claim 1, characterized in that: The bioflocculant described in step 4 is a bioflocculant produced by Paecilomyces 1-1.

8. The method for treating industrial wastewater based on infrared spectroscopy detection technology according to claim 1, characterized in that: The industrial waste water contains manganese, mercury and chromium.

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