Sterilization of Water-Based Cutting Fluids Using Compact Air-Cooled Coaxial Dielectric Barrier Discharge Reactor with Bubbler

Abstract

Odor and discoloration in water-based cutting fluids are caused by the growth of microorganisms and putrefying bacteria. This significantly reduces cutting performance, prevents rust, and deteriorates the working environment. To overcome these drawbacks, we developed a compact air-cooled coaxial dielectric barrier discharge (DBD) with a bubbler. Bacteria and microorganisms living in waste cutting fluids were sterilized by the high concentration of ozone produced under the optimized conditions of the compact air-cooled coaxial DBD. Moreover, it was confirmed that 99.99% of bacteria and microorganisms were completely removed. Ozone was found to not affect property changes such as the composition, concentration, and pH of the water-based cutting fluids. The chromaticity and complex odor of waste cutting liquids were thus found to have been improved by the effects of microorganism and bacterial sterilization. We conclude that the proposed a compact air-cooled coaxial DBD with a bubbler is an efficient method for sterilizing water-based cutting fluids.