Abstract
A water recovery method from a difficult-to-process water-soluble coolant was developed. The methods with an oil-decomposed microorganism and a freeze-thawing showed a little potential to recover the water. The demulsifying by an activator was very effective to recover the clear water. The recycle water obtained by activator method had 7.5 of pH and 0.1% of Brix%. The water-soluble coolant can stable emulsion in the recycle water. The recycle coolant diluted with recycle water showed the same pH and Brix% as those of virgin coolant. There was no difference in lapping force change, removal rate and finishing surface roughness between the lapping of SUS304 with recycle and virgin coolants. These facts indicate that the recycle water recovered from a difficult-to-process coolant can be re-utilized as a diluter of renewal coolant.
