SFGP 2007 -- A New Concept for the Abatement of Volatile Organic Compounds by a Two-Stage Process Combining Non-Thermal Plasma Treatment and Filtration

A new process combining non-thermal plasma treatment and filtration has been studied for the treatment of diluted gaseous effluents containing VOCs. The removal of a VOC model molecule, beta-pinene, in air was studied. The results showed that the pollutant was chemically modified by soft oxidation reactions in the plasma treatment step and that the resulting products could be trapped on a filter with high efficiency. As a result, the process was less energy-consuming compared to complete oxidation. The pollutant could be injected before or after the discharge zone without affecting the performance of the process. Nopinone, identified by GC-MS analyses, is the main product of the plasma treatment step. It was hypothesized that this product results from the oxidation of beta-pinene by 'excited' ozone produced by the discharge and the destruction of beta-pinene. The product was therefore modelled by a second-order reaction between beta-pinene and ozone. In the second part of this work, a semi-industrial scale pilot capable of treating a gas flowrate of 50 m(3)/h was built. The pilot was designed with the assistance of process simulations made by coupling a flow model ( obtained by a CFD code) and the previous kinetic model. The results show that the performances of the pilot measured experimentally were in agreement with the predicted ones.