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POWDER COATING ENVIRONMENTAL QUESTION

A gentleman wants to locate a metal powder coating operations which he purchased in our community. My concern is what effect will his operation have on our wastewater treatment plant? The wash process leaves heavy metals in the rinse water I am told which he intends to flush into our sanitary sewer line. Also the oven process leaves an ash residue I'm told. Any help you can offer.

Thanks,

Timothy Dill
municipal government - Mt Horeb, Wisconsin, USA
2004

The single biggest reason for the popularity of powder coating is probably how benign it is environmentally. It is similar to paint in its end result, but the coating is done without the use of any solvent by applying powder electrostaticly, and heating it until it melts onto the parts.

I don't think ashing is a routine part of powder coating, but at some point the powder that accumulates on conveyor hooks and such must be removed, and burning it off is again a way to do it without using solvents.

Metal does have to be cleaned and prepared before powder coating, and the application of a zinc or iron phosphate makes the part corrosion resistant and acceptable for use. Pretreatment of industrial wastewater is routine; I think the coater, the POTW, and the city fathers simply need to agree as to what, if anything, is necessary in terms of pretreatment of wastewater before release to the POTW.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004