EVALUATION OF FILTRATION AND DISTILLATION METHODS FOR RECYCLING AUTOMOTIVE COOLANT

This evaluation addresses the product quality, waste reduction, and ec onomic issues involved in recycling automotive and heavy-duty engine c oolants at a New Jersey Department of Transportation garage. The speci fic recycling units evaluated are based on the technologies of filtrat ion and distillation. Results show that the filtration unit evaluated needs improvement to ensure an acceptable quality of the recycled cool ant. Distillation results show that this technology provides acceptabl e product quality and good waste reduction and economic potential. The New Jersey garage could potentially reduce waste from over 8000 gals/ yr to approximately 400 gal/yr. The recycled product in the distillati on evaluation passed selected ASTM performance tests. Boiling point, f reezing point, pH, corrosion resistance, and foam control functions of the coolant were restored to specifications. Chemical characterizatio n of the recycled coolant showed that metals, salts and organic contam inants were either removed or reduced to levels where they posed no si gnificant problems.