LCCO2 of coal co-firing with imported torrefied woody biomass in Japan

Abstract

In response to Japan's increase on coal dependence, co-firing of woody biomass in a coal power plant has been considered as the most feasible sustainable alternative. We propose torrefaction as an effective method to improve the quality of biomass fuel. To measure how much CO2 can be avoided by utilizing torrefied fuel, Life Cycle CO2 (LCCO2) of woody biomass co-firing in the Japanese coal power plant was conducted in this study. As a comparative analysis in the LCCO2, scenarios constructed included the use of woody biomass in the form of chip, pellet, and torrefied fuel. Due to the unavailability of large quantity domestic feedstocks in Japan, Indonesia was chosen as the origin of the imported woody biomass in the simulated scenarios. The results showed that significant CO2 reduction could be achieved especially in the co-firing that includes torrefied fuel. In the case where 30cal% of torrefied fuel or 5cal% of pellets were used for co-firing in a 50 MW capacity coal power plant, 95,000 t of CO2 could be avoided annually compared to using 100% coal.