气氛对神木煤部分气化煤焦再气化动力学参数的影响

EFFECT OF ATMOSPHERE ON THE REGASIFICATION KINETIC PARAMETERS OF CHAR PARTIALLY GASIFIED FROM SHENMU COAL

在小型固定床上制备了一系列的神木煤部分气化煤焦,运用热天平分析了它们在不同气氛下的再气化动力学行为。结果表明,部分气化煤焦再气化动力学参数随部分气化煤焦气化率的变化而有规律的变化。在H2O气氛下再气化时,随着部分气化煤焦气化率的增加,活化能、指前因子与气化剂分压指数减小;在CO2气氛下再气化时,结果则有所不同,随着部分气化煤焦气化率的增加,活化能与指前因子增加,气化剂分压指数减小;无论何种气氛下再气化时,部分气化煤焦的活化能与指前因子均具有补偿效应。

A series of SM (Shenmu) partially gasified chars were prepared in a micro-scale fixed-bed. The regasification kinetics of these partially gasified chars for different atmosphere was analyzed by a thermobalance. Results show that the regasification kinetic parameters of partially gasified chars are related with gasification conversion of coals. For gasification in steam, the regasification activation energy, preexponential factor and effect of the pressure of steam on the gasification rate decrease with the increase of gasification conversion, but for gasification in CO_2, the regasification activation energy and preexponential factor increase, the effect of the pressure of CO_2 on the gasification rate decreases. It is important to point out that the compensation effect exists between activition energy of partially gasified chars and preexponential factor during gasification regardless of atmospheres.