褐煤热破裂的显微CT实验  

Micro-CT experimental of the thermal cracking of brown coal

作　　者：孟巧荣[1] 赵阳升[1] 胡耀青[1] 冯增朝[1] 徐素国[1] 

机构地区：[1]太原理工大学采矿工艺研究所,山西太原030024

出　　处：《煤炭学报》2011年第5期855-860,共6页Journal of China Coal Society

基　　金：国家自然科学基金重大资助项目(50534030);国家自然科学基金资助项目(50874077;50804033)

摘　　要：采用μCT225kVFCB型高精度显微CT试验系统并配以微型气氛炉,研究了内蒙古平庄褐煤热破裂随温度的变化关系。研究结果表明,褐煤在100℃左右时,大裂隙（〉800μm）占主导地位;200℃左右时,中等裂隙（100~400μm）占主导地位;300℃之后微裂隙（〈100μm）占主导地位;热破裂的阈值为300℃左右;在300℃之前孔隙裂隙的产生发展主要是因为热破裂,300℃之后,微裂隙和孔隙的产生主要是因为煤体发生热解化学反应,油气逸出,固体骨架逐渐转变为半焦体。Using μCT225kVFCB high precision micro-CT system and a small moveable argon furnace,thermal cracking of brown coal from Pingzhuang mining in Inner Mongolia municipality was studied under different temperature.The results show that for brown coal,the big cracks(>800 μm) occupy leading position at about 100 ℃,the medium cracks(100~400 μm) are more important than others at about 200 ℃,the micro-cracks(<100 μm)become dominant above 300 ℃;threshold temperature of thermal cracking is 300 ℃,more or less;when temperature is lower than 300 ℃,the formation and evolution of crack and pore result mostly from thermal cracking,above 300 ℃,micro-cracks and pores produce mainly because coal pyrolysis produce and release oil gas,and turn coal skeleton into char gradually with temperature.

关 键 词：褐煤 热破裂 显微CT 热解 孔隙 

分 类 号：TQ530.2[化学工程—煤化学工程]