Abstract
To reduce the environmental load of water-soluble coolants, authors have been studying a metabolic system for water soluble coolants. In the metabolic system, water resources are recovered from water-soluble coolant waste and reused as a diluent for new coolant. In this report, we focused on the operation and recycling use of amine-free water-soluble coolant. Most of water-soluble coolants contain alkanolamines for corrosion inhibition and maintenance of pH. However, alkanolamines are difficult to eliminate from water-soluble coolant in waste treatment. Some amine-free water-soluble coolants are commercially available, regarded as environmentally friendly cutting fluids. We examined stability and recyclability of amine-free water-soluble coolant.
