Tar removal from biomass-derived fuel gas by pulsed corona discharges. A chemical kinetic study

Tar (heavy hydrocarbon or polycyclic aromatic hydrocarbon) removal from biomass-derived fuel gas is one of the biggest obstacles in its utilization for power generation. We have investigated pulsed corona as a method for tar removal. Experimental results have indicated the energy density requirement to be 400 J/L for naphthalene removal (model tar compound) from synthetic fuel gas (CO, CO2, H2, CH4, N2) at a temperature of 200 °C. For the process to be competitive and economical, the energy consumption needs to be reduced. This requires an understanding of the chemical processes involved. In previous studies, we have investigated the primary processes at a temperature of 200 °C. The present study aims to identify the main reactions involved by means of a sensitivity analysis. Results indicate that, apart from CO, which apparently seems to be the most terminating species for the reactive O radical at a temperature of 200 °C, formaldehyde, formed during radical reactions, also acts as a major quencher.