At present, there are about 10000 electroplating factories and factories in China, and about 50% of the 4 billion yuan of wastewater discharged annually does not meet the national discharge standards. Wastewater contains harmful substances such as heavy metal ions, organic mediators, and inorganic mediators. These substances entering the environment will inevitably cause widespread and serious harm to the ecological environment and humanity. The treatment of electroplating wastewater is still a small and negligible issue.
Electroplating wastewater treatment
The electroplating industry is an industry related to the national economy and people's livelihood, as well as an industry with high pollution and high water consumption. If the wastewater generated is discharged without reaching the standard, it will cause great harm to the water body, thereby endangering aquatic animals and plants, as well as crops, animals, and humans that rely on it for survival. Although the treatment of electroplating wastewater in China has a history of over 50 years, the relevant industry discharge standards were only introduced in 2008.
The treatment methods for electroplating wastewater are divided into physical, chemical, and biochemical methods according to their principles. For electroplating wastewater, multiple treatment methods need to be combined and treated according to the quality in order to achieve the best treatment effect. Under the environmental theme of clean production, energy conservation and emission reduction, the reuse of electroplating wastewater, heavy metal recovery, and zero emission processes are increasingly receiving widespread attention. Some environmental requirements have increased from standard emissions to micro emissions and zero emissions. However, how to properly treat or reuse the high salt content in the current process of this type of process is one of the difficulties in the reuse of reclaimed water. In addition, many electroplating processes, such as the electroplating of precision electrical components and high-end handicrafts, involve precious metal coatings, such as gold plating and silver plating. As a result, gold cyanide wastewater and Silver cyanide wastewater are generated. If gold and silver are not recycled, valuable raw materials will be wasted and the cost of wastewater treatment will be increased. Nowadays, most of them adopt a resin specifically designed for adsorbing gold and silver in wastewater, which can effectively recover and generate income for wastewater treatment systems and comply with the concept of circular economy.
There are many methods for treating electroplating wastewater. On the basis of traditional treatment methods, actively developing new methods to reduce treatment energy consumption, treatment costs, improve treatment efficiency, and meet the call for clean production, energy conservation and emission reduction in today's new processes must have epoch-making significance.
