不同粒径煤样低温氧化过程升温速率规律研究

Study on Low-temperature Oxidation Heating Rate Regularity of Coal Samples with Different Particle Size

基于程序升温试验系统研究了柠条塔矿6种粒径煤样低温氧化过程的升温速率变化规律,对比分析可知:升温速率随煤样粒径的减小而增大;6个粒径煤样的升温速率曲线相似,均呈W形走势,并且各曲线存在明显的分阶段特征:常温至临界温度(小于65℃),氧化升温速率缓慢增大;临界温度至干裂温度(65~105℃),氧化升温速率先增大后减小;大于干裂温度(大于105℃),氧化升温速率持续稳定增长。从煤氧复合微观机理分析出各阶段参与反应的活性基团、化学键种类和数量的不同是造成升温速率呈现阶段性特征的主要原因。

The low-temperature oxidation heating rate regularity of coal samples with six particle sizes in ningtiaota coal mine was studied based on temperature-programmed experiments system.The contrastive analysis results showed that:the heat rate would increase while the particle size of coal samples decreased,the heating rate curves of six particle sizes were similar and presented a Wshaped trend.And each curve presented obvious stage characteristics:the normal temperature to critical temperature ( less than 65 ℃) ,oxidation heating rate increased slowly;critical temperature to xerochasy temperature (65~105 ℃),oxidation heating rate decreased firstly and then increased;more than xerochasy temperature ( more than 105℃) ,the oxidation heating rate declined sharply and reached its minimum value near the chapped temperature,and then continued to grow.From micro level analysis,the various stages involved in the reaction of reactive groups, different types and quantities of chemical bond was the main reason to cause the heating rate presents stage characteristics.