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Electrolytic removal of zinc in waste water [New Zealand]

Hi Ted,
If I wanted to remove dissolved zinc in our waste water can I do it in the same principle as electroplating? If so in one sentence or more how please? Thanking you in advance.

Dennis Marriott
Plant manager - Christchurch, New Zealand
July 28, 2010

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July 30, 2010

Hi, Dennis. It perhaps can be done if the zinc concentration is very high. The issue is that, although zinc does preferentially plate out before water separates into hydrogen and oxygen, if you have a low concentration of zinc, and anything less that super-high surface area and super-short anode to cathode distance, the efficiency will be near zero.

Regards,

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

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August 9, 2010

Just a precaution. Many years ago I tried to electrowin zinc from a dragout rinse on a barrel plating line. It plated out, but once the deposit got more than a few thousandths of an inch thick, it peeled from the cathode which short circuited the cell. No damage was done, but a short circuit of this type can cause a fire.

Use fuses or circuit breakers on the cathodes to protect against a short circuit.

Lyle Kirman

Lyle Kirman
consultant - Cleveland Heights, Ohio