Development of Multi-Compartment Dielectric Barrier Discharge Plasma Reactor for Innovative Water Treatment

Abstract

A novel multi-compartment dielectric barrier discharge (MCDBD) plasma rector is developed and tested to produce plasma-activated water (PAW). MCDBD reactor consists of a polycarbonate container with six compartments. The top electrodes are stainless steel needles connected to AC high-voltage power supply. The bottom of each compartment is replaced with a glass slab and stainless-steel mesh electrodes. Cold plasma is generated in all compartments simultaneously to activate water. Experiments conducted by varying treatment time, power levels, gap between electrodes and water surface, and volume of water. Production of reactive oxygen and nitrogen species (ROS and RNS, respectively) in PAW is evaluated as per international standards (APHA/AWWA/IS). The application PAW greatly depends on the ROS and RNS concentration so results of MCDBD reactor are compared with conventional reactors. ROS and RNS concentration in 1800 mL water is measured 0.93 M and 0.52 M, respectively, in the MCDBD reactor. ROS and RNS concentration in 500 mL water is found to be 0.6 M and 0.44 M, respectively, in a conventional reactor. Result shows higher concentration of ROS and RNS produced in large volumes of water using MCDBD reactors. Even though the same amount of power is supplied to both conventional and multicompartment reactors, output in terms of ROS and RNS production is significantly greater in new design. Also, ROS and RNS have longer life in MCDBD reactor which is desirable to deactivate the biofilms and water decontamination. Proposed design is found to be more suitable for wastewater treatments, biomedical and agriculture applications.