The electroplating industry is an important field in the manufacturing industry, which is widely used in automotive, electronics, aerospace, construction and other industries. However, the electroplating process generates large amounts of wastewater containing contaminants such as heavy metals, organics, and acids and alkalis.
Electroplating wastewater mainly contains pollutants such as heavy metals (such as copper, nickel, chromium, zinc, etc.), organic matter, acid and alkali, cyanide and so on. The harm of these pollutants to the environment is mainly manifested in the following aspects:
Heavy metal pollution: Heavy metals are difficult to degrade, accumulate through the food chain, and may eventually enter the human body, causing long-term harm to human health.
Organic pollution: The decomposition of organic matter in the environment will produce foul odors, affect air quality, and may cause problems such as eutrophication of water bodies.
Acid-alkali pollution: If the acidity or alkalinity of wastewater is too high or too low, it will cause harm to aquatic organisms and destroy the ecological balance.
According to the characteristics of electroplating wastewater, the commonly used treatment technologies include physical, chemical, biological and their combination processes.
Physical methods: including precipitation, filtration, adsorption, etc. Suspended solids, particulate matter and some heavy metals in wastewater are removed by physical methods.
Chemical methods: including neutralization, redox, precipitation, complexation, etc. By adding chemicals, the pollutants in the wastewater are converted into harmless or low-toxic substances, which is convenient for subsequent treatment.
Biological method: the use of microbial metabolism to degrade organic matter in wastewater. The biological method is suitable for the treatment of electroplating wastewater with high organic content.
Combined process: According to the specific situation of wastewater, the physical, chemical and biological methods are combined to form a multi-stage treatment process to improve the treatment effect.