Abstract
The coal pyrolysis is the important reaction that has much influence on initial situations in coal combustion and gasification processes. The authors recently proposed the extended CPD model. This model can describe primary tar compositions as actual chemical species. As a result, it became possible to calculate the gas phase decomposition behavior by using a gas phase reaction mechanism in existence. CO_2,O_2 and H_2O gasification experiments on 2 types of coal were simulated by combining the cxtended CPD model, a gas phase reaction mechanism and char gasification models. The soot yield did not decrease in CO_2 gasification, while it decreased in O_2 or H_2O gasification. These phenomena were described by the simulation well. Furthermore, it was suggested that the mechanism to decrease soot (PAH) was different between O_2 and H_2O.
