Plasma-catalytical removal of tars from fuel gas obtained by biomass gasification

Special Issue on selected papers from The 10th International Conference on Photocatalysis: Fundamentals and Applications and The 11th International Conference on Advanced Oxidation Technologies for Treatment of Water, Air and Soil, Chicago, Illinois, USA October 24-27, 2005 In view of the worldwide concern about the depletion of fossil fuels and environmental problems associated with these sources, biomass is getting increased attention as a source of renewable energy and chemicals. Biomass gasification has a significant higher biomass to power efficiency than biomass combustion. However, gasification of biomass also produces significant amounts of heavy hydrocarbons (referred to as "tars") along with particulates. These tars will condense in downstream equipment, or deposit on active sites of catalysts, leading to loss of activity and the need for frequent regeneration. Hence it is necessary to remove the tars. Here we discuss the use of pulsed corona and plasma-catalysis as alternative methods for catalytic and thermal treatment. In both catalytic as well as thermal treatment processes, the fundamental mechanism involves creation and stabilizing of reactive species, which thereafter initiate the necessary reactions under kinetic and thermodynamic limitations. The same can be expected to occur in a non-thermal plasma, where similar species can be created by energetic electron-molecule collisions