COREX炉内块煤裂化成焦后的粉化现象研究-有色金属科学与工程.DOC

熔融气化炉内块煤成焦后粉化现象的相关研究 刘肖，刘起航，湛文龙，梁磊，任海亮，吴铿 (北京科技大学钢铁冶金新技术国家重点实验室，北京 100083) 摘要：采用200 kg级炼焦炉对熔融气化炉主要使用的两种块煤进行了不同时间的半焦裂解试验，比较了两种块煤成焦后的粒度分布和强度变化，发现B煤在炼焦炉内粉化严重，随结焦时间的延长其粒度降解度一直在升高，而A煤降解度在达到最大值后开始下降。对比了两种块煤生成半焦的矿相微观结构，A煤生成的半焦主要以镶嵌结构和各向同性结构为主，而B煤生成的半焦主要以类丝炭和各向同性结构为主；两种半焦均含有未成焦煤。通过分析熔融气化炉内取出的风口试样中不同粒度的含碳物质其矿相微观结构，认为在炉缸内6.3mm的颗粒由两种块煤裂解成焦后的粉化现象所引起，且B煤的粉化是主要因素。 关键词：熔融气化炉；块煤成焦和粉化；矿相微观结构；风口试样 中图分类号：TF557 Investigation on pulverization phenomena of coke formed by lump coal pyrolysis in melter gasifier LIU Xiao, LIU Qi-hang, ZHAN Wen-long, LIANG Lei, REN Hai-liang, WU Keng (State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing, 100083) Abstract：Through the different pyrolysis time tests in 200 kg coke oven of lump coal mainly used in melter gasifier, namely A coal and B coal, the size distribution and strength change of the two coals after coking was compared. Results showed that the pulverization of B coal in coke oven was severe, which size degradation rate (DR) was always increasing with the coking time prolonging. On the contrary, the DR of A coal was decreasing once reached the maximum value. The mineral microstructure of semi coke formed by the two coal pyrolysis in coke oven was also compared. It was found that semi coke formed by A coal was mainly mosaic and isotropy stucture, and the other semi coke formed by B coal was mainly fusain and isotropy structure. There was still some coal residue in both semi cokes. Through the mineral microstructure analysis of different particle size of carbon-containing materials in tuyere samples taken out from melter gasifier, it was found that the particles less than 6.3 mm in hearth were caused by the semi coke pulverization. Moreover, the pulverization of semi coke was mainly form B coal. Keywords: melter gasifier; coal pyrolysis and pulverization; mineral microstructure; tuyere sample 1前言 COREX流程是一种有别于高炉生产铁水的新工艺，采用块矿或球团矿、非炼焦煤及部分焦炭作为原料，是目前世界上唯一成功实现工业化生产的熔融还原炼铁技术[1-3]。COREX使用块煤代替优质焦炭，可缓解对炼铁过程