Carbonization Characteristics of Woody Biomass, Grindability and Combustibility for Carbonized Woody Biomass

Abstract

The purpose of this study is to propose the control parameters during the wood carbonization, and to provide that the grindability and combustibility of the carbonized woody biomass are suitable for co-firing at pulverized coal power station. In this study, the authors conducted experiments of wood carbonization and of pulverizing and combustion of carbonized wood and obtained the following results. (1) Carbonized wood characteristics (such as energy yield and calorific value per weight) have a relatively low correlation coefficient with the measured carbonization temperature and a high correlation coefficient with the fixed carbon and weight yields of the carbonized wood. The weight yield observed during carbonization process can be a practical operation control index of the carbonizer. (2) The carbonized wood could be pulverized using the roller mill of the coal-fired power plant without modification. In the pulverization process, the energy consumption of the carbonized wood is close to that of coal. After the pulverizing process, the particle size of the carbonized wood is larger than that of coal. However, particles of the carbonized wood were combusted well like coal and the combustion gas satisfied environmental qualities. Using carbonized wood, it is expected to increase co-firing rate of biomass and reduce CO₂ emissions in coal-fired power plants.