39.石炭の高温・高圧下におけるガス化反応の速度論

抄録

It had been reported that the gasification rate of coal char measured by a thermobalance (TG) is much smaller than the rate measured by a drop-tube furnace (DTF) at high temperature. In this work we succeed in obtaining the gasification rate that is very close to the rate measured by DTF by gasifying a small amount of sample (<0.3mg) using a TG. The char particles were placed in a platinum mesh basket in highly dispersed state in the TG. Using this experimental technique, we clarified that CO_2, gasification rates of seven kinds of chars were controlled by chemical reaction up to 1200℃ for char particles less than 75μm. At 1300℃ the difference in the gasification rates among the seven chars was found to be very small due to the shift of rate controlling step from the chemical reaction controlling region to the intraparticle diffusion rate controlling region.