O-08 木質バイオマスと石炭との混焼発電によるBECCSの成立条件の検討

抄録

Bio-energy with CCS (CO₂ capture and storage), called as BECCS, is expected to be a promising method to reduce the atmospheric CO₂ concentration. In this study, conditions under which negative CO₂ emission can be achieved in BECCS using pulverized coal-fired power plant (500 MWe, thermal efficiency:38 %(HHV)) with co-firing with woody biomass have been investigated. The results from the analysis showed that the critical co-firing ratio of biomass to coal, which is defined as the ratio over which the net CO₂ emission is negative, strongly depended upon the CO₂ recovery rate in CCS and increased with decreasing the CO₂ recovery rate. The critical co-firing ratio was around 10 % when the CO₂ recovery rate was 90%. On the other hand, the CO₂ capture and storage energy varying from 1 to 4 GJ/t-CO₂ had little influence on the critical co-firing ratio.