A method for treating electroplating wastewater

Abstract

This invention discloses a method for treating electroplating wastewater, relating to the field of electroplating wastewater treatment technology, comprising the following steps: Step 1: Mixing domestic sewage and electroplating wastewater under certain conditions to induce chemical reactions between their respective pollutants; Step 2: Visually observing whether the interaction of pollutants can produce flocculants; Step 3: Based on the experimental studies in Step 1 and Step 2, measuring the transmittance of the visually clear and transparent treated water using a 721 spectrophotometer; This method for treating electroplating wastewater removes organic pollutants and reduces its COD value to meet discharge standards by mixing domestic sewage and electroplating wastewater, removes harmful heavy metal ions to meet discharge standards, and further reduces the treatment cost of the mixed wastewater.

Description

Technical Field

[0001] This invention relates to the field of electroplating wastewater treatment technology, specifically to a method for treating electroplating wastewater. Background Technology

[0002] For many years, people have been continuously researching water treatment technologies for various types of wastewater. The main sources of water pollution fall into three categories: industrial pollution, agricultural pollution, and domestic pollution. Industrial pollution mainly refers to wastewater discharged during industrial production processes. This type of wastewater has the most complex composition and causes the most serious pollution to water bodies. For example, wastewater containing highly toxic organic compounds discharged from dyeing and printing plants, wastewater discharged from paper mills, and wastewater containing large amounts of heavy metal compounds discharged from electroplating plants pose a significant threat to the environment. Therefore, the electroplating industry is one of the world's largest polluting industries. Agricultural pollution is mainly attributed to the extensive use of pesticides and fertilizers in recent years. Urban domestic sewage is wastewater generated in daily life, mainly including kitchen and washing wastewater, toilet and bathing wastewater, etc. The water treatment methods currently in use are mainly physical, chemical, or biochemical methods, which remove or transform pollutants into harmless substances through physical, chemical, or biochemical processes. The appropriate physical, chemical, or biochemical method can be selected for treatment depending on the nature of the pollutants in the wastewater. Over the years, these water treatment technologies have played a vital role in treating various types of wastewater, protecting the environment, and providing clean water for human survival and development. However, with human development and technological progress, the volume of discharged wastewater is constantly increasing, and the pollutants are becoming more complex, making treatment increasingly difficult and costly. Therefore, the development of water treatment technologies with stronger treatment effects and lower costs is urgently needed. To this end, a method for treating electroplating wastewater is proposed. Summary of the Invention

[0003] In view of the shortcomings of the prior art, the present invention provides a method for treating electroplating wastewater, which solves the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a method for treating electroplating wastewater, comprising the following steps:

[0005] Step 1: Under certain conditions, domestic sewage and electroplating wastewater are mixed and treated to induce chemical reactions between their respective pollutants;

[0006] Step 2: Then, visually observe whether the interaction of pollutants can produce flocs;

[0007] Step 3: Based on the experimental research in Step 1 and Step 2, the transmittance of the treated water, which appears clear and transparent to the naked eye, was measured using a 721 spectrophotometer.

[0008] Step 4: Measure the COD value and heavy metal ion content of the treated water, and then determine the possibility of mixed treatment;

[0009] Step 5: Use an infrared spectrometer to measure the infrared spectra of pollutants in the untreated wastewater and the flocculants after mixed treatment, and analyze the chemical interactions between the pollutants in the two types of wastewater.

[0010] Optionally, in step one: treating domestic sewage and electroplating wastewater by mixing them under certain conditions to allow their respective pollutants to react chemically, it is necessary to set the treatment conditions for mixing domestic sewage and electroplating wastewater. These conditions include different ratios of domestic sewage and electroplating wastewater, changes in pH value, changes in temperature, flocculation treatment conditions, and other additives.

[0011] Optionally, the ratio of domestic sewage to electroplating wastewater includes: 8:2, 6:4, 4:6 and 2:8.

[0012] Optionally, the pH changes include 7, 8, 9, and 10.

[0013] Optionally, the temperature change includes 35 degrees, 40 degrees, 45 degrees, 50 degrees and 55 degrees.

[0014] Optionally, the flocculation treatment conditions are based on mixing intensity, and the other additives include inorganic flocculants, organic flocculants, other organic substances, and other inorganic substances.

[0015] Optionally, in step three: through the experimental studies in steps one and two, the transmittance of the treated water, which appears clear and transparent to the naked eye, is measured using a 721 spectrophotometer; in step four: the COD value and heavy metal ion content of the treated water are measured, and the possibility of mixed treatment is determined; and in step five: the infrared spectra of pollutants in the wastewater before treatment and flocculants after mixed treatment are measured using an infrared spectrometer to analyze the chemical interactions between pollutants in the two types of wastewater. The transmittance of the water sample with the best apparent treatment effect is used to determine the COD value and heavy metal ion content of the treated water, and the infrared spectra of the residues before and after treatment are measured.

[0016] Optionally, step two involves visually observing whether the interaction of pollutants can produce flocs, and if flocs are produced, how well they settle.

[0017] This invention provides a method for treating electroplating wastewater, which has the following beneficial effects:

[0018] The method for treating electroplating wastewater involves mixing domestic sewage with electroplating wastewater to remove organic pollutants and reduce its COD value to meet discharge standards. It also removes harmful heavy metal ions to meet discharge standards and further reduces the treatment cost of the mixed wastewater. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the steps of the present invention. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0021] Please see Figure 1 This invention provides a technical solution: a method for treating electroplating wastewater, comprising the following steps:

[0022] Step 1: Under certain conditions, domestic sewage and electroplating wastewater are mixed and treated to induce chemical reactions between their respective pollutants;

[0023] Step 2: Then, visually observe whether the interaction of pollutants can produce flocs;

[0024] Step 3: Based on the experimental research in Step 1 and Step 2, the transmittance of the treated water, which appears clear and transparent to the naked eye, was measured using a 721 spectrophotometer.

[0025] Step 4: Measure the COD value and heavy metal ion content of the treated water, and then determine the possibility of mixed treatment;

[0026] Step 5: Use an infrared spectrometer to measure the infrared spectra of pollutants in the untreated wastewater and the flocculants after mixed treatment, and analyze the chemical interactions between the pollutants in the two types of wastewater.

[0027] Furthermore, those skilled in the art will know that step one, which involves mixing domestic sewage and electroplating wastewater under certain conditions to induce chemical reactions between their respective pollutants, requires setting treatment conditions for the mixed treatment of domestic sewage and electroplating wastewater. These treatment conditions include different ratios of domestic sewage and electroplating wastewater, changes in pH value, changes in temperature, flocculation treatment conditions, and other additives.

[0028] Furthermore, those skilled in the art will know that the mixing ratios of domestic sewage and electroplating wastewater include 8:2, 6:4, 4:6, and 2:8. Based on the source of domestic sewage, it is known that the pollutants in domestic sewage are mainly biologically active organic matter, such as fats, starches, and proteins, while electroplating wastewater mainly contains heavy metal ions that are highly toxic to the human body. Mixing the two can utilize the chemical reaction between organic and inorganic matter, allowing each pollutant to act as a treatment agent for the other, ensuring that the mixed wastewater meets discharge standards after treatment, thus protecting the aquatic environment. By changing the mixing ratio of domestic sewage and electroplating wastewater and testing the treated water quality data, the optimal wastewater mixing ratios for treatment effects were determined.

[0029] Furthermore, those skilled in the art will recognize that pH changes include 7, 8, 9, and 10. pH significantly impacts wastewater treatment. The molecules of fats, starches, and proteins in domestic wastewater contain hydroxyl, amino, or ester groups, which have lone pairs of electrons that can form coordinate bonds with heavy metal ions. Pollutants in the water treatment system can also self-assemble into flocs through other chemical reactions such as hydrogen bonding, thereby removing pollutants from the water. Heavy metal ions in electroplating wastewater are generally strong acid-weak base salts. Adding alkaline substances can produce metal hydroxides, which can then polymerize into polynuclear metal hydroxides, excellent flocculants. Therefore, by changing the pH value and testing the water quality data after treatment, the optimal pH value for wastewater treatment can be determined.

[0030] Furthermore, those skilled in the art will understand that temperature changes, including 35°C, 40°C, 45°C, 50°C, and 55°C, significantly affect chemical reactions. On the one hand, increased temperature promotes the rapid movement of pollutant particles, causing them to collide and undergo chemical reactions. On the other hand, excessively high temperatures can sometimes disrupt the chemical reactions between pollutants. By varying the temperature and testing the water quality data after treatment, the optimal treatment temperature can be determined.

[0031] Furthermore, those skilled in the art will understand that flocculation treatment conditions are related to mixing intensity. Other additives include inorganic flocculants, organic flocculants, other organic matter, and other inorganic matter. Flocculation treatment conditions have a significant impact on the quality of the treated water. For water treatment, two key factors are mixing intensity and settling time. From the perspective of facilitating the chemical interaction between pollutants in domestic sewage and electroplating wastewater, a higher mixing intensity is more effective. However, excessively high mixing intensity can also disrupt the chemical interaction between pollutants, requiring practical investigation to determine the optimal mixing intensity. Settling time also significantly affects the quality of the treated water. Theoretically, a longer settling time should result in better effluent quality. However, in actual treatment, treatment efficiency must also be considered. The determination of settling time should aim to maximize treatment efficiency while ensuring effluent quality.

[0032] Furthermore, those skilled in the art will know that step three involves: through the experimental studies in steps one and two, measuring the transmittance of the treated water, which appears clear and transparent to the naked eye, using a 721 spectrophotometer; step four involves measuring the COD value and heavy metal ion content of the treated water, and then determining the possibility of mixed treatment; and step five involves using an infrared spectrometer to measure the infrared spectra of pollutants in the wastewater before treatment and the flocculants after mixed treatment, analyzing the chemical interactions between the pollutants in the two types of wastewater. This includes testing the transmittance of water samples with good apparent treatment effects, measuring the COD value and heavy metal ion content of the treated water, and testing the infrared spectra of the residues before and after treatment.

[0033] Furthermore, those skilled in the art will know that step two involves visually observing whether the interaction of pollutants can produce flocs, and if flocs are produced, how well they settle.

[0034] Example

[0035] Test results of electroplating wastewater and domestic sewage:

[0036] Table 1. Test results of mixed treatment of electroplating wastewater and domestic sewage (domestic sewage sampling point: Jingzhou Senlian Domestic Sewage Treatment Plant, COD value: 45 mg / L; electroplating wastewater sampling point: Jingzhou Bafang Electroplating Chemical Plant)

[0037]

[0038] The results in the table above show that the water treated under condition 5 had the best water quality indicators. This means that at room temperature and with a 1:9 ratio of electroplating wastewater to domestic sewage, the COD value met the standard, and both heavy metal and COD levels were below the detection limit. If the temperature is raised to 55 degrees Celsius and a small amount of sodium hypochlorite is added, the COD value can be reduced even further, to below 4 mg / L.

[0039] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for treating electroplating wastewater, characterized in that: Includes the following steps: Step 1: Under certain conditions, domestic sewage and electroplating wastewater are mixed and treated to induce chemical reactions between their respective pollutants; Step 2: Then, visually observe whether the interaction of pollutants can produce flocs; Step 3: Based on the experimental research in Step 1 and Step 2, the transmittance of the treated water, which appears clear and transparent to the naked eye, was measured using a 721 spectrophotometer. Step 4: Measure the COD value and heavy metal ion content of the treated water, and then determine the possibility of mixed treatment; Step 5: Use an infrared spectrometer to measure the infrared spectra of pollutants in the wastewater before treatment and the flocculants after mixed treatment, and analyze the chemical interactions between the pollutants in the two types of wastewater. Step 1: By mixing domestic sewage and electroplating wastewater under certain conditions, chemical reactions are generated between their respective pollutants. This requires setting the treatment conditions for mixing domestic sewage and electroplating wastewater. The treatment conditions include different ratios of domestic sewage and electroplating wastewater, changes in pH value, changes in temperature, flocculation treatment conditions, and other additives. The ratio of domestic sewage to electroplating wastewater includes: 8:2, 6:4, 4:6 and 2:8, 9:1; The pH changes include: 7, 8, 9, and 10; The temperature changes include room temperature, 35 degrees, 40 degrees, 45 degrees, 50 degrees and 55 degrees; The other additives include inorganic flocculants, organic flocculants, other organic substances and other inorganic substances; Step 3: Based on the experimental research in Step 1 and Step 2, the transmittance of the treated water, which appears clear and transparent to the naked eye, is measured using a 721 spectrophotometer. Step 4: The COD value and heavy metal ion content of the treated water are measured to determine the possibility of mixed treatment. Step 5: The infrared spectra of pollutants in the wastewater before treatment and the flocculants after mixed treatment are measured using an infrared spectrometer to analyze the chemical interactions between the pollutants in the two types of wastewater. The transmittance of the water sample with good apparent treatment effect is tested, the COD value and heavy metal ion content of the treated water are measured, and the infrared spectra of the residues before and after treatment are tested.

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