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Zinc phosphate sludge

I would like to know how to calculate how much sludge is produced in a nitrite-accelerated Zinc phosphate Pretreatment system with the introduction of aluminum alloys(specifically, 6111 & 6022).

Any advice that could be given would be much appreciated! I would also be interested in any pertinent research that has been conducted.

Thanks,

Douglas Cauvet
Troy, MI, USA
2001

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If the solution used is specifically for aluminum parts, The Canning Handbook [on eBay, Amazon, AbeBooks affil links] says that, in this case, the bath can contain alkali metal cations which precipitate aluminum fluo-aluminates.

You will need to find out the chemical reaction taking place in your particular solution, and calculate the weight of the precipitate based on the amount of aluminum reacted (a surface area and weight removal/conversion question). You can estimate the weight, add some for side reactions (such as with oxygen from the air), then figure out how this stuff settles during treatment to find sludge volume in the wastewater.

  
Tom Pullizzi
Falls Township, Pennsylvania
2001