Model Calculation of Negative Wire-Cylinder Corona Discharge Properties in Humid Synthesis Gas
T. Hammer
Siemens AG, Corporate Research & Technology, Germany
Abstract— For the final clean-up of the synthesis gas produced from a small scale biomass gasification plant having a gas flow rate of 35 kg/hr a wet ESP was designed and tested. Design was supported by model calculations of the current-voltage characteristics of the wire-tube precipitator. Electronic and ionic properties of multi-component gas mixtures were evaluated from cross section data using a Boltzmann code and ion mobility formulas. Both for synthesis gas and humid air simulated corona inception voltages exceeded measured ones for about 20-30%, and simulated currents were 20-30% too low. The deviation between measured and simulated corona inception voltages may be due to the surface roughness of the unpolished wire used. Electrons contributing to the current in the drift region of the corona are assumed to be the reason for the larger currents observed in the experiments.
Keywords— Wet electrostatic precipitator, biomass gasification, producer gas, numerical simulation