For heavy metal wastewater treatment, it is necessary to clarify which types of heavy metals are generated by different factories before implementing targeted treatment. This article briefly discusses heavy metal wastewater treatment arising from electroplating processes.
Electroplating refers to a technological process that uses chemical means to provide surface protection and decorative effects for metals or scrap metals, as well as endow surfaces with new properties. To guarantee the quality of electroplated products, the metal coating should be flat and smooth and form stable bonding with the substrate. Therefore, surface contaminants on work-pieces need to be thoroughly removed before plating. A large volume of electroplating wastewater containing heavy metals will be produced during this cleaning process. Such wastewater shall undergo proper treatment before discharge. Direct discharge may bring potential risks to the ecological environment. Hence, effective treatment of electroplating heavy metal wastewater is essential, and Wastewater Monitoring helps reflect the actual effect of water treatment.
The treatment of electroplating heavy metal wastewater involves relatively complex considerations. Comprehensive evaluation should be carried out based on internal factors including wastewater quality, water volume, electroplating production processes, production load and operation management. In addition, its composition is difficult to regulate. It mainly contains heavy metal pollutants such as copper, hexavalent chromium, zinc, silver and nickel, which carry toxic properties, and some substances may pose carcinogenic risks to human bodies.
What kinds of wastewater are generally produced in electroplating activities? They include electroplating rinsing wastewater, passivation wastewater, floor washing wastewater and pickling wastewater for plated work-pieces. Wastewater may also be generated due to improper operation or accidental incidents such as liquid leakage. Electroplating wastewater pollutes the environment through two main routes: one is wastewater with large flow rate and relatively low pollutant concentration; the other is waste liquid with small volume but high pollutant concentration.
The goal of wastewater treatment is to separate harmful and toxic substances from the water body for recovery and reuse, or convert toxic substances via chemical reactions to reduce related toxicity. In general, industrial wastewater, medical wastewater and other types of wastewater all require appropriate treatment. Meanwhile, monitoring work for industrial wastewater, medical wastewater and other wastewater types should also be arranged.
