煤焦CO2气化反应中石灰石催化特性研究

研究了新鲜石灰石和经过煅烧/碳酸化反应(CCR)反复循环后的石灰石在烟煤煤焦CO2气化反应中的催化特性.结果表明,固定碳转化率随新鲜石灰石添加比例的增加而增大,石灰石添加比例为5％时其催化特性达到最佳,且催化活性随气化温度的升高而降低；在不同热解温度下添加2.5％新鲜石灰石制得的煤焦的气化特性与气化温度密切相关,当气化温度高于热解温度时,催化活性基本不受热解温度影响；随着CCR循环次数的增加,低温气化时石灰石催化活性比新鲜石灰石略低,但仍可作为煤焦气化反应的有效催化剂.

STUDY ON CATALYTIC PROPERTY OF LIMESTONE IN GASIFICATION REACTION OF COAL CHAR WITH CO2

The catalytic property of fresh limestone and limestone after repeated circulating calcination and cabonation reactions(CCRs) in gasification reaction of bituminous coal char with CO2 has been studied,study shows that the conversion rate of fixed carbon increases as the adding proportion of fresh limestone increases,the catalytic property of limestone is optimal when its adding proportion was 5%,and the catalytic activity was decreased as the gasification temperature was increased,the gasification property of coal char prepared from adding 2.5% limestone under different pyrolysis temperatures had close relationship with gasification temperature,the pyrolysis temperature basically hadn’t effect upon the catalytic activity when the gasification temperature was higher than the pyrolysis temperature;along with increasing the CCRs,the catalytic activity of limestone was slightly lower than that of fresh limestone under lower gasification temperature,but it could still be an effective catalyst for gasification of coal char.