褐煤热爆特性及影响因素试验研究

Experimental study on characteristics of lignite thermal cracking and its influence factors

为提高我国褐煤的利用效率,选取呼伦贝尔、元宝山、乌兰察布、兴安盟、宝清褐煤为研究对象,以粒度变化率作为衡量热爆性的指标,考察了煤质、初始平均粒径、受热温度、水分对褐煤热爆性的影响,并研究了热爆后碎片的结构特性。试验结果表明:褐煤的变质程度不同,热爆性有较大差别;初始平均粒径越大,受热温度越高,褐煤的热爆性越强;水分是影响褐煤热爆的重要因素,150℃下干燥1 h后样品的热爆性与原煤相比可降低50%以上;褐煤在热爆过程中产生了大量新孔,褐煤的水分和挥发分越高,热爆后碎片的孔隙结构越发达。

In order to enhance the utilization efficiency of lignite in China, taking the lignites samples from Hulunbeier, Yuanbaoshan, Wu- lanehabu,Xinganmeng and Baoqing Area as research subjects, and chosing the change rate of particle size as the measure index of thermal cracking, the paper investigated the effects of coal rank, initial average particle size, heating temperature and moisture content on lignite thermal cracking, the structure characteristics of the debris after thermal cracking were also studied.The results showed that lignite＇ s ther- mal cracking property were different with different coalification degree.The larger the initial average particle size was, and the higher the heating temperature was, the stronger the thermal cracking of lignite would be.The moisture content of lignite was the major factor affected its thermal cracking, after drying 1 hour at 150 ℃ , the thermal cracking of the sample could be decreased by more than half compared with raw coal.The lignite produced a lot of new holes in the thermal cracking process, the higher the moisture content and volatile content of lignite were, the more developed the pore structure of the debris after thermal cracking would be.