The effects of de-humidification and O2 direct injection in oxy-pc combustion

Abstract

This study is aimed to derive effects of de-humidification and O 2 direct injection in oxy-PC combustion system. Temperature distribution and flue gas composition were observed for various air and oxy-fuel conditions such as effect of various O2 concentration of total oxidant, O2concentration of primary stream and O2 direct injection through 0-D heat and mass balance calculation and experiments in the oxy-PC combustion system of 0.3MW scale in KITECH (Korea Institute of Industrial Technology). Flame attachment characteristic related to O2 direct injection was also observed experimentally. We found that FEGT (furnace exit gas temperature) of 100% de-humidification to oxidizer is lower than humidification condition; difference between two conditions is lower than 20°C in all cases. The efficiency changing of combustion was negligible in O2 direct injection. But O2 direct injection should be carefully designed to produce a stable flame. © Tsinghua University Press, Beijing and Springer-Verlag Berlin Heidelberg 2012.