Nickel Recovery from Electroplating Rinsewater by Electrodialysis

PACIFIC NW POLLUTION PREVENTION RESEARCH CENTER
POLLUTION PREVENTION RESEARCH PROJECTS DATABASE

Project Title: Nickel Recovery from Electroplating Rinsewater by Electrodialysis

Date Last Updated: 5/96

Project Summary: The goal of this study was to evaluate the technical, pollution prevention, and economic issues involved in using an electrodialysis recovery system to recover rinsewater and nickel from the nickel-plating line in a metal finishing plant.

Results indicate that nickel concentration was reduced from nearly 3,000 mg/L in the rinse tank to less than 100 mg/L in the stack outlet and rinse recycle tank waster. Other contaminants are reduced similarly. Both cation and anion levels (total dissolved solids) were reduced by electrodialysis. As much as 90% of the nickel is removed from the water loop as the water makes a pass from the dialysis feed tank to the stack outlet water stream. The rest of the nickel remains in the rinsewater returned to the rinse tank. Thus, all the nickel is recovered and reused. The nickel removed from the water loop accumulates in the concentration loop. On the test day, the evaporator was not functioning properly, and the nickel level in the concentrate could not be brought up to that in the plating baths.

Using the electrodialysis system, the nickel and water are recovered and reused. Researchers estimate that approximately 29,964 lbs. of nickel is recovered and reused annually. With the recovery unit absent, it is estimated that 1,077,000 gal/yr of wastewater would require treatment, and nickel-contaminated sludges would require disposal as hazardous waste. Because these wastewater treatment costs are eliminated , there is a payback period of one year on the system, based on a capital cost of $110,000 for the electrodialysis unit. The long-term effects of closing the nickel recovery loop still are a concern, and future research into the operation of this system is needed to ensure good product quality and to reduce maintenance requirements.

Project Keywords: electrodialysis, metal finishing, plating, nickel, wastewater

Organization Performing Research: Connecticut Hazardous Waste Management Service; Battelle, Columbus Labs

Primary Research Contact: not reported

Date Research Started/Completed: 1994

Publications Based on Research: "Nickel Recovery from Electroplating Rinsewater by Electrodialysis" by Arun Gavaskar, et al., will be available as an EPA/600 series report.
Full report and project summary available through either:
* CERI Publications Unit, US EPA
26 W. Martin Luther King Drive
Cincinnati, OH, 45268
(513) 569-7582
or
* National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
(703) 487-4650

Approximate Project Budget: not reported

Primary Project Funder: US EPA

Funder Contact:
Paul Randall
US Environmental Protection Agency
National Risk Management Research Lab
26 West Martin Luther King Dr., MS 466
Cincinnati, Ohio 45268
phone: (513) 569-7673
fax: (513) 569-7677
e-mail: randall.paul@epamail.epa.gov