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Characteristics of chromium plating wastewater

February 5, 2009

hi
I'm an undergrad student who is currently working on chromium wastewater treatment for my plant design class. I would like to inquire about the typical wastewater characteristics from coming from chromium plating?
thank you

Veronica Tupaz
student - Philippines

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First of two simultaneous responses --

The waste water composition from chromium plating will differ depending on if you are using the traditional hexavalent form or the more environmentally friendly trivalent form.

Both will contain chromium metal in an acidic stream. The state of the chromium will differ with the process. The hexavalent stream would also typically include sulphates and if a proprietary solution is used (for decorative chromium plating) could also contain fluorides and borates. Some of the chromium present may be divalent or trivalent although the process is hexavalent. Others (proprietary hard chrome) may contain other sulphates which would include chromium/MSA complexes. Trivalent baths would typically have chlorides rather than sulphates in the stream and contain trivalent chrome compounds as well as traces of proprietary chemistry.

Gene Packman
process supplier - Great Neck, New York
February 7, 2009

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Second of two simultaneous responses --

It cannot be answered as some shops are slop shops and some are state of the are in pollution prevention. Also most chrome shops do other types of plating, at least one kind of nickel and up to 3 kinds of nickel, plus who knows what else.

James Watts
- Navarre, Florida
February 7, 2009