Remove Impurities from Metal

Electrowinning is a widely used technology in various industries, including metal recovery, mining, refining and wastewater treatment.

Electrowinning, alternatively referred to as electroextraction, is the traditional electrodeposition of metals from dissolved or liquified ores to recover waste metals via the rinse system while minimizing wastewater generation and chemical discharge. Due to the relative value of gold, silver, copper, cadmium, and zinc is a widely used method in modern metal recovery, mining, refining, and wastewater treatment applications. Both electrorefining and electroplating employ large-scale electroplating to remove impurities from metals and are necessary procedures for cost-effective and straightforward nonferrous metal purification.

A traditional electrowinning unit consists of a tank, rectifier, and pump. Cathodes and anodes are aligned inside the tank, and the pump fills the tank with the electrolytic solution. Because of the difference in electrical potential, cations migrate toward the cathode when current is supplied to cathodes and anodes. As a result, positively charged ions will eventually plate on the cathodes. It’s important to remember that as metal accumulates on the cathode, the amount of metal deposited in the solution decreases, slowing plating. When the metal deposition rate is insufficient for electroplating, the cathodes with pure metal deposited will be harvested. Nonferrous metals are removed from the solution (wastewater) in wastewater treatment, then chemically precipitated or reused in the industrial process.

Our Revolutionary Electrowinning Rotacat

The revolutionary rotating cathode cell from Trionetics allows for the rapid recovery of metals in nugget form for reclamation or reuse from concentrated process streams. High yields and low overall operating costs can be achieved using rotating cathodes and turbulent solution flow through clean seed media. However, plating down to discharge limits is impossible because plating efficiency drops to around 0.5 ppm with revolving cathodes. A typical application is the ability of ion exchange regenerants to be treated and reused multiple times. The revolving cathode barrel can be replaced with a high-efficiency cathode (mailbox) to meet plating discharge limits.