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Wastewater recycling

Replace wastewater evaporation (burn-off) with water recycling and reuse?
            Any suggestions?
We are working with a facility doing remanufacturing of a particular automotive part (size: 2 quarts or larger) in substantial quantities.
Exteriors of received cores are cleaned to remove grease and grime in high pressure washers and rock tumblers using an aqueous biodegradable industrial detergent from ChemStation. Plastic media blasting is used to remove paint, if necessary.
The cleaned units are dismantled, their internal components cleaned with the ChemStation industrial detergent in wash tanks and/or ultrasonic tanks.
All aqueous waste streams are evaporated in a Burn-Off oven.  Oven is propane heated.  Wastewater is transferred from the different stations in 55-gallon drums to the 80-gallon oven tank.  Not a large waste stream (approx. 55-110 gallons per day, depending on one or two shifts); around 10,000 gallons of water a year is evaporated requiring 7,180 lbs of propane.
Batch evaporation takes about six hours.  The powdered oven residue is disposed off.
We are looking into a recycling system for this wastewater, including the air compressors' blow back oily water, to replace the water burn-off.  Further, these 10,000 gallons may increase with an additional 600 gallons of wastewater a month when another activity will be put into operation early next year.  Quality and quantity of that particular wastewater stream is an unknown at this time.  Contaminant here would be a resin type compound.  Closed-loop recycling is not immediately seen as feasible with the current facility's cleaning setup (with or without the new activity).
Second topic:
While we are at it, mineral spirits are being used to clean special bearings.  1000 gallons a year.  They say all the aqueous cleaners tested so far were without success.
* Clearers that worked for you?
* Vendors of solvent stills?
Happy Holidays!
Don Wielkens
Retired Engineer
Pollution Prevention Program
Florida Department of Environmental Protection
2600 Blair Stone Road, MS 4570
Tallahassee, FL 32399-2400
Home: (813) 908 9170