Degradation of Persistent Materials by Pulsed Barrier Discharge Generated in Gas-Liquid Two-Phase Flow

摘要

A liquid- phase electrical discharge reactor has been studied to decompose persistent substances inwater. Fast rising pulsed voltages generate short-lived pulsed barrier discharges in gas-liquidtwo-phase flow, which is a mixed state of gas and aqueous solution. The decomposition rate andenergy efficiency are evaluated by measuring the amount of total organic carbon in the solution ofacetic acid as a persistent substance. They are strongly affected by the bubble fraction of thetwo-phase flow and the discharge gas species, such as He, Ne, Ar, and oxygen. The visible lightemission from the discharge suggests that intense discharge is generated at the gas-liquid boundarylayer where the discharge current flows directly from the water capacitor surrounding the gasbubbles. The decomposing efficiency seems to be high because the energy loss by the joule heatingof water is quite small.