The flame in O2/CO2 pulverized coal combustion simulation

The O(2)/CO(2) pulverized coal combustion is one of the promising system to recover CO(2) from exhaust gas of boiler, and it has lower flame temperature. So it is found that lower NO conversion is obtained on O(2)/CO(2) combustion. In this paper, combustion test has been conducted on O(2)/CO(2) condition, and the results show that O(2)/CO(2) pulverized coal combustion reveals less ignition stability and emits a relatively smaller amount of NO(x) than conventional combustion. In order to improve combutibility of O(2)/CO(2) pulverized coal furnace, the combustion numerical simulation was performed. The physical models include the k-epsilon turbulence model, the network radiation model, the EBU volatiles combustion model and particle track model for the motion of particles. More reactal model is used to describe coal devolatilization and char combustion. The results of the numerical simulation have relatively a good agreement on distribution of gas temperature with those obtained in the combustion test.