突出煤体视密度测定技术研究

Study on Measuring Technology for Apparent Density of Outburst Coal

为解决突出煤体由于粒径过小导致其视密度测定结果不准确的问题,通过理论分析煤样粒径与视密度之间的关系,并运用自主研制的视密度测定装置,选取全国各地9个不同变质程度的煤样,提出了模拟煤层法测定突出煤体视密度的新方法。结果表明:很小范围内煤体视密度随煤体粒径的增加而减小后趋于常数;随着煤体变质程度增大其视密度呈现先变大后变小的变化规律,这和煤体变质程度与微孔体积、孔隙度、吸附能力变化规律相吻合;每个煤样在相同的水分、粒径、成型压力和围岩压力下对其视密度测定2次,对测定结果进行误差分析,分析发现不同煤样视密度测定误差均小于0.5%,不同煤样之间所得的视密度误差最大为0.33%。

In order to solve the problem that the apparent density measurement result of the coal body is inaccurate due to its small particle size,the feasibility of the coal seam apparent density measurement by simulating coal seam method is researched by theoretical analysis of the relationship between the coal sample particle size and the apparent density.Using the self-developed visual density measuring device,nine coal samples with different metamorphic degrees from different parts of the country were selected for experimental study.The results show that:in a very small range,the apparent density of coal samples increases with the decrease of the particle size of coal samples.When the particle size of coal samples is large enough,the apparent density of coal samples will tend to nearly constant value.With the increase of coal metamorphism,the apparent density of coal increases first and then decreases,which is same to the change rule of coal metamorphism degree and coal micropore volume,porosity and coal adsorption capacity.For each coal sample measured twice under the same moisture content,particle size,molding pressure and surrounding rock pressure,the analysis found that the apparent density measurement error is less than 0.5%;the error difference of the apparent density obtained is no more than 0.33%.