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The efficacy of electropolish through a waste treatment system

I have a waste treatment system that deals with five waste streams. Chrome, Nickel, cyanide,cleaners, acid/alkaline. I presently use sulfuric acid to adjust ph in the chrome, cyanide stage #2, and final effluent. I'd like to use an electropolish waste, which is sulfuric and phosphoric acid, to adjust ph in my chrome and cyanide stage #2. All five waste streams run to a reaction #1 tank which is adjusted for ph and a coagulant is added. It flows to a reaction #2 tank where sulfide is added and the ph is raised to 10.2. It flows into a concentration tank which feeds my microfilter. How will the addition of the phosphoric affect my cyanide reaction? How will it affect my membranes ? What type of byproduct will there be?

Robert Albrecht
electroplating shop - Lawrence, Massachusetts
2005

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2005

Since you have all the solutions you want to test, this is a perfect time for a bench test. Your laboratory (the laboratory you have in your plant) should be set up with all the necessaries to run tests on 2 liter solutions of waste. So you need a dozen 2 liter beaker [beakers on eBay or Amazon [affil links] s, and pipette [pipettes on eBay or Amazon [affil links] , pipette bulbs, stirring rods, pH and ORP meters.

If you must, you can send samples to an outside laboratory to do the work, but pick a laboratory that is not selling chemical addition agents for waste treatment. You may be able to get a retired chemist to come into your lab to get this work done, if you know of any, or you can get a name from a university nearby.

  
Tom Pullizzi
Falls Township, Pennsylvania

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2005

I'm a little worried that nickel from your electropolishing solution will react with any remaining cyanide to form a very difficult to treat, nickel cyanide complex.

This is a case where jar testing and dynamic testing may yield different results.

Lyle Kirman
consultant - Cleveland Heights, Ohio