ELECTRIC FIELD EFFECT ON BIOMASS COMBUSTION CHARACTERISTICS

The main aim of the present study is to obtain clean and effective heat energy production by applying a DC electric field to the flame reaction zone and providing control of the processes developing at thermochemical conversion of biomass (wood) pellets. The average heat power of the experimental device with continuous supply of pellets at an average supply rate of 1.1-2 g·s -1 and optimized flame structure is ~20 kW. The electric field effect on combustion characteristics is estimated from field-induced variations of the flame temperature, composition and combustion efficiency by varying the applied voltage and ion current between the electrodes. The mechanism of field-enhanced variations of the combustion characteristics is analyzed with account of the field-induced ion wind effects on the biomass thermal decomposition and on the formation of the flame reaction zone. A previous experimental study of the electric field effect on the combustion characteristics at thermochemical conversion of biomass (wood pellets) was carried out using a batch-size experimental device with integrated processes of biomass gasification and combustion of volatiles with an average heat power of 2-3 kW. The goal of the present study was to investigate the DC electric field effect on the thermochemical conversion of biomass pellets using continuous supply of pellets onto the bottom of the combustor, with the single electrode configuration. The electric field-induced variations of the flame composition, temperature and combustion efficiency were tested and discussed considering the electric field effect on the combustion stability.