Comparative modelling of NOx and SO2 removal from pollutant gases using pulsed-corona and silent discharges

A comparative modelling of pulsed-corona and silent discharges for removal of NOx, NyOx, SO2, CO and CH2O using operating equipment is presented. The main purpose is to compare, by modelling, the energy efficiency on removal of toxic impurities between two types of discharges at similar gas composition and temperature. Three different gas compositions: diesel engine exhaust, methane combustion products and pollutant air are considered. The simulation is based on an approximate mathematical model for plasma cleaning of a waste gas. The influence of non-uniform species distributions arising from a great number of streamer or microdischarge channels in a discharge chamber is taken into account. The modelling is carried out for a pulse series, considering after each discharge pulse the chemical and diffusion processes inside and outside the streamer trace. The distinctions of the cleaning processes in the pulsed-corona and barrier discharges are presented. It is also recommended when each of the examined discharges should be used.