Combination of VOC degradation and electro-hydrodynamic pumping actions in a surface dielectric barrier discharge reactor

Abstract

This paper concerns the study of a surface dielectric barrier discharge (SDBD) reactor designed for offering simultaneously chemical (VOC degradation) and mechanical (electro-hydrodynamic pumping) actions. It takes the form of a channel composed of active faces on which surface plasma is generated in AC sinusoidal mode with a resonant power-supply. The chemical application targeted is the flexible and low energy-cost abatement of VOC present in air at low concentration, which is a major current industrial concern for safety and environmental reasons. Regarding the mechanical action, the SDBD acts as a pump. It is able to induce flow rates reaching up to 153L/min for a 60W consumption with an electro-mechanical yield of 0.0133% in open configuration, while as any pump, it falls down in connected configuration; 39L/min connected to our air treatment bench. Regarding the chemical action, five VOC are tested, two ketones: acetone and butanone, two esters: methyl-butyrate and methyl-valerate, one aldehyde: butyraldehyde. They are injected at low concentration in a continuous air flow according to two modes of injection: (i) separately at 25ppmv, or (ii) together at 10ppmv each one, i.e. 50ppmv total. The air flow rate is modulated via an additional pump for investigating an extended range: 8.5–179L/min. Thus, for a fixed 60W consumption, the specific input energy (SIE) goes from 20J/L to 423J/L. As expected, the results show that as the SIE is increased, better conversion rates are achieved. Based on the experimental results, a chemical model of the SDBD reactor is proposed for providing a physical interpretation while giving information for helping the design of an optimized double-action reactor.