粉碎法快速测定煤的坚固性系数实验探究

为寻求一种新的煤的坚固性系数(简称“f值”)快速测定方法,以实现煤矿井下工作面煤体f值的现场测定,采用高速旋转机械粉碎煤样的破碎方式开展煤体f值快速测定(简称“粉碎法”)实验研究。根据现场实际及煤样粉碎的正交试验结果,确立了煤样粉碎时间、煤样质量及粉碎机转速的最优参数组合,基于此对不同矿井不同煤层所采集的煤样开展粉碎实验,研究了煤样粉碎后的煤屑在不同粒度区间的质量占比与煤样f值之间的相关关系。结果表明:煤样粉碎后粒度小于0.5 mm的煤屑质量占比与煤样f值的乘幂关系式拟合效果最优,拟合度达0.9311;同时利用现行测定标准方法“落锤法”对基于“粉碎法”测定的煤样f值结果进行验证,其误差均不超过8%,表明应用“粉碎法”快速测定煤体f值是合理准确且可行的。

Experimental study on rapid determination of coal hardiness coefficient by crushing method

In order to find a new method of rapid determination on coal hardiness coefficient(referred to“f value”),for achieving in-situ determination of coal f value in the underground working face,carried out f value rapid determination method(referred to“crushing method”)laboratory research by high-speed rotating and mechanical crushing of coal sample broken way.According to the actual situation on site and the coal sample crush orthogonal experiment results,the optimal combination of grinding parameters on coal sample crushing time,coal sample quality and grinding speed was established.Based on this,crushing experiments was carried out in coal samples collected from different coal seams in different mines.Correlation between coal f value and coal quality accounted for the proportion with different size fractions after coal sample crushing was studied.The results show that the exponentiation fitting relation of coal cinder quality accounting less than 0.5 mm after the coal sample crushed and coal f value is optimal,and the fitting degree reaches 0.9311;at the same time,the current measurement standard“drop hammer method”is used to verify the measurement results of crushing method.f value,the measurement error is not more than 8%,it is verified that the established“crushing method”for rapid determination of f value is reasonable and feasible.