Chromate Recovery from Chromating Rinsewater in the Metal Finshing Industry

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Project Title: Chromate Recovery from Chromating Rinsewater in the Metal Finshing Industry

Date Last Updated: 5/96

Project Summary: A chromate recovery unit was installed and operated at a Connecticut metal finishing plant. The purpose of this research was to analyze the characterization of distillation still bottoms and chromate tanks, and compare the major operating costs before and after installation of the recovery system. Rinsewater from the plant will be processed through the recovery unit, and concentrated to approximately 200 gal. of final concentrate per year.

This recovery system prevents the generation of large volumes of wastewater and hazardous sludge that otherwise would result from the chromating operation. Further pollution prevention would be possible at plants that use only one formuation (this plant uses three different chromate formulations), through potential reuse of the chromium contained in the still bottoms. Zinc and iron levels would have to be closely monitored if such reuse was practiced.

Capital costs for the project were roughly $87,000 with a payback period of 4 years. This recovery system has potential for use in many applications that generate wastewater. A negative effect is the relatively high energy consumption of the recovery unit. Future versions of this system are aiming to reduce this energy requirement.

Project Keywords: chromate, metal finishing, wastewater, rinsewater

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: "Chromate Recovery from Chromating Rinsewater in the Metal Finshing Industry" by Arun Gavaskar, et al. The full report 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