Influence of Electrode System Geometry on Efficiency of Particle Collection of a Compact Electrostatic Precipitator for Small Scale Biomass Combustion

Abstract

In the study, attention is given to the development of a compact electrostatic precipitator (ESP) for small-scale biomass combustion facilities. A pilot ESP was tested, being installed downstream the wood-chips and wood-pellets boilers and the wood-logs stove. A DC negative corona discharge was used for particle charging. The ESP was operated at corona voltages up to 22,1 kV and corona currents up to 2,1 mA. The ESP included a casing with gas input and output sections and a grounded removable ash-box installed at a casing bottom part. The ESP with elongated barbed HV electrodes, installed axially inside the gas input section, was characterised with low corona discharge power consumption and reduced particle mass collection efficiency. The next generation electrode systems were tested which included disk and quadrat form barbed HV electrodes, installed inside the ash box, which was used as an opposite electrode. The optimization of HV electrode system geometry enhanced the long-term operation stability of the ESP, ensuring mean mass collection efficiency of 75%.