摘要
采用低温热解法(450～650℃)对褐煤进行改性处理,研究热解终温对褐煤半焦成浆特性的影响,并从煤质特性和微观孔隙结构的角度对成浆性改变的原因进行了分析,选用Herschel-Bulkley模型对浆体流变特性进行拟合分析,直观地显示了水煤浆流变特性随浆体浓度和热解终温的变化情况。实验结果表明:低温热解有效地提高了褐煤的成浆性能,褐煤水煤浆的最大成浆浓度由改性前的44.31%,最大可升至66.78%,热解终温越高,定黏浓度越大。在表观黏度相近的情况下,热解终温越高,半焦水煤浆的稳定性越好。低温热解能有效脱除褐煤中的水分,促进含氧基团的分解,提高煤阶。热解后,煤的孔隙结构发生变化,热解终温升高,孔比表面积和孔容积减小。
The low temperature （450-650℃） pyrolysis method was used to modify lignite. The effect of pyrolysis temperature on the slurry ability of lignite semi-coke was studied. The coal characteristics and microscopic pore structure characteristics were investigated to explain the change of the slurry ability. Herschel-Bulkley model was chosen to carry out fitting analysis of slurry rheological characteristics, which directly indicates how slurry rheological characteristics changes as the concentration slurry alters. The results show that low temperature pyrolysis effectively improves the slurry ability of lignite. The maximum solid concentration increases maximally from 44.31% to 66.78%. Increasing temperature leads to the rise of the maximum solid concentration. The stability of slurries becomes better with the increase of pyrolysis temperature when apparent viscosity of slurries is approximate. Low temperature pyrolysis can effectively dehydrate lignite, promote oxygen groups decomposition and improve coal rank. The pore structure characteristics change after pyrolysis, the specific surface area and volume of pore decrease with the rise of heating temperature.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2013年第8期36-43,8,共8页
Proceedings of the CSEE
基金
国家重点基础研究发展计划项目(973项目)(2010CB227001)~~
关键词
低温热解
褐煤
半焦
水煤浆
成浆特性
low temperature pyrolysis
lignite
semi-coke
coal water slurry
slurry ability
