Effects of Pretreatment on the Flash Pyrolysis Behavior and the Coking Properties of a Non-Fusible Coal

摘要

Coal pretreatmenls such as acid treatment and preheal-trcalinents ib the temperature range of 370 - 450°C by the different heating rates were examined in order to improve the flash pyrolysis reactivity and the coking properties of a non-fusible coal. It is found that mild acid treatments gave the larger macro-porosity to the pyrolyzed char. The preheattreatment at 410°C under the rapid heating condition of l50 °C/min improved the coking properties with the higher block density, while the heattreatment at 450°C by the slow heating rate of 5°C/min gave the silmilar effect. The preheattreatment around 400°C under the pressurized condition was effective for the improvement of the fusibility of non-fusible coals. The mechanism and effect of coal pretreatments are briefly discussed based on the above results and chemical analyses of gaseous and residual products.