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How to dry paint overspray collected in a water bath?

Currently the company manufactures car parts. The overspray that doesn't make it onto the part goes into a water system and then into a main water pit. We then use centrifuges to remove the paint from the water system. The centrifuges produce a sludge that we must ship out as hazardous waste to be dried and then shipped to a landfill. I am looking into the idea of using either a sludge press or drier so that we can dry the sludge ourself instead of using another company to dry it for us. I was wondering if anyone had any ideas of what kind of a press or dryer would be best to use? We produce around 150 L of sludge a day with 2 centrifuges.

Michael Schiestel
Engineering Technician - ON, Canada
August 12, 2008

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I would not use a centrifuge. I'd chemically de-tackify the suspended paint and floc it out with alum and polymer. If you get the chemistry right you should be able to get a lower volume of readily dewaterable sludge.

Dave Wichern
Consultant - The Bronx, New York
August 15, 2008