An environmental and economic comparison of ion exchange and recently commercialized electrochemical technologies for the recovery of rinse water in a bright nickel plating facility

摘要

Researchers at the USEPA are testing and evaluating two commercial electrochemical technologies for the purification of rinse water and the recovery of copper and nickel from a variety of electroplating processes. One of the investigated technologies is based on the application of high surface area carbon based electrodes in a radial flow cell that maximizes mass transfer and current efficiency. The other investigated technology uses a novel electrochemical ion exchange cell that is regenerated electrochemically. This paper discusses the engineering fundamentals, economics and environmental costs of utilizing these novel electrochemical technologies for rinse water recovery at a small bright nickel plating facility. For this study, the primary objectives were: 1) to recover rinse water; 2) assure compliance with existing environmental regulations; and 3) determine the feasibility of reducing or eliminating the need for an off-site ion exchange service. At this facility it was not desired to return the recovered nickel directly to the process. Impact assessment analysis and a conventional payback analysis are used to compare these new electrochemical processes with each other and the existing ion exchange recovery unit.