Study on the characteristics of biomass for co-combustion in coal power plant

In this study, a torrefaction experiment was carried out using domestic woody biomass (waste wood and logging residue) and overseas herbaceous biomass (PKS: palm kernel shell and bagasse). Torrefaction was performed in a nitrogen atmosphere using a batch-type apparatus, either with changing torrefaction temperature or with changing duration at a constant temperature. Here, only the oxygen contained in the biomass was used in the torrefaction experiment. The physical and chemical properties of biomass fuels produced under various torrefaction conditions were investigated to determine their characteristics as fuels for coal firing power plant. Based on thermogravimetric analysis (TGA), proximate analysis of four kinds of biomass, and the result of varying the torrefaction temperature and duration, each of the biomass residues was torrefied for 30 min at a temperature range of 250–350 °C in an anaerobic conditions. Consequently, when compared with the raw material, each of the torrefied materials showed lower moisture and volatile matter content, fixed carbon and ash content, and higher calorific value.