采用程序升温氧化试验装置对准东大井矿区主采Bm煤层进行了氧化特性试验。研究了其不同粒径煤样自燃临界温度TC、CO初始温度、格雷哈姆指数及CO、O2随温度的变化和其它CnHm气体初始温度。试验表明:在该试验条件下,CO初始温度随煤样粒径的减小而增加,平均CO初始温度为66.37℃;随煤样粒径减小,临界温度有所增加,平均临界温度为154.73℃;Ta-TCO段平均耗氧速率为0.2454mL/min·℃-1,TCO-Tb段平均耗氧速率为4.0049 mL/min·℃-1;随氧化进程继续(即TCO-Tb段),80~100目粒径煤样温度耗氧速率高于120~140目、160~180目粒径煤样耗氧速率,表明该阶段其反应活性大于其他粒径实验煤样反应活性;70~100℃范围内实验煤样R3较R1、R2表征作用更明显;根据氧化特性实验数据,可将CO、温度、O2浓度、格雷哈姆指数R3及C2H4、C2H6、C3H8作为矿井防灭火监测指标指导采场煤自燃火灾防治。
With the application of programmed temperature-rising coal oxidation experimental apparatus,the authors conducted experiments to study the oxidation process of the major mining coal seam of eastern Junggar coalfield with different particle sizes.Some special parameters,such as the critical spontaneous combustion temperature Tc,the initial temperature for producing the CO,the Graham indexes,the change of CO and O2 with the increase of temperature,and other CnHmgases,were analyzed in the present paper.Results show that the initial temperature of CO increases with the reducing of particle sizes.The average initial CO temperature is about 66.37℃,and this phenomenon doesnt represent this sample has more intensity of reaction than that of others.It also shows that the critical temperature increases with the reducing of particle sizes,and the average critical temperature is about 154.73℃.At the stage of Ta-TCO,the average oxygen-consumption rate is about 0.2454mL/min·℃-1,and at the stage of TCO-Tb,the rate is about 4.0049mL/min·℃-1.With the progress of oxidation,the oxygen-consumption rate of 80~100mesh size sample is higher than that of 120~140mesh size and that of 160~180mesh size,which indicates that the 80~100mesh sample has much more reaction activities than that of both 120~140mesh and 160~180mesh sizes.At the range of 70~100℃,Graham index R3 has much ability to indicate the coal spontaneous combustion than that of R1 and R2,which can be used to predict the coalspontaneous combustion.From this research,it is probably to choose the CO concentration,the temperature,the O2 concentration,the Graham index R3,the C2H4,the C2H6,and the C3H8 to indicate the coal spontaneous combustion in coal mine.