文献类型：期刊文献

英文题名：Effects of in-situ interactions between steam and coal on pyrolysis and gasification characteristics of pulverized coals and coal water slurry

作者：Ding, Lu[1];Dai, Zhenghua[1];Guo, Qinghua[1];Yu, Guangsuo[1]

机构：[1]East China Univ Sci & Technol, Key Lab Coal Gasificat & Energy Chem Engn, Minist Educ, Shanghai Engn Res Ctr Coal Gasificat, Shanghai 200237, Peoples R China

年份：2017

卷号：187

起止页码：627

外文期刊名：APPLIED ENERGY

收录：;EI(收录号：20164903094703);WOS:【SCI-EXPANDED(收录号:WOS:000392571200049)】；

基金：This work has been partially supported by the National Natural Science Foundation of China (21376081), and the National High Technology Research and Development of China (863 program, 2012AA053101).

语种：英文

外文关键词：Pyrolysis; Gasification characteristics; Water contents; Carbon microcrystalline structure; Interactions

摘要：The effects of water on the pyrolysis and gasification characteristics of coal water slurry (CWS) and pulverized coals with different ranks have been studied in the present work. Rapid pyrolysis characteristics (i.e. char yield, char structure evolution) of raw carbonaceous materials with varied water contents were investigated by using a high frequency furnace at 800-1200 degrees C. Moreover, gasification characteristics of the pyrolysis char were studied by using a thermogravimetric analyzer (TGA). The results indicate that at the pyrolysis temperature of 800 degrees C, the char yield of Wu-ran-cha-bu (WRCB) lignite slightly decreased with increasing the water content from 2.1 wt.% to 13.98 wt.%, while that of Yun-nan (YN) lignite showed a more significant decrease with increasing water content from 2.2 wt.% to 11.54 wt.%. This could be attributed to a higher coal reactivity of YN lignite than that of WRCB lignite. When the pyrolysis temperature was at or above 1000 degrees C, due to more significant in-situ coal-steam interactions, a lower char yield of both the pulverized lignites were observed with increasing water content from 2 wt.% to above 10 wt.%. CWS char presented a higher graphitization degree than pulverized coal char. The carbon micro crystalline structure factors (i.e. L-002/d(002) value) of pyrolysis char increased with coal rank, which might reflect the variation trend of the graphitization degree from low rank coal to high rank coal. During the rapid heat treatment processes, the water evaporation and the in-situ steam-char gasification were favorable for void formation for both pulverized coals with high water contents and CWS. Notably, during the gasification processes of three different rank coals at 1200 degrees C, a more significant inhibition effect of residual ash on CWS char was observed compared to the pulverized parent coal char with high carbon conversion (x > 0.9). (C) 2016 Elsevier Ltd. All rights reserved.