动态图像法测量煤样粒度粒形研究

Study on Particle Size of Coal Sample Measured by Dynamic Image Method

选取云南何兴煤矿煤样,用动态图像法测量了1~3 mm煤样8份,每份20 g。实验发现:动态图像法测量粒度分布实验重复性好,测量数据可信度较高;费雷特最小直径、最大内切圆直径按颗粒数量统计基本一致;实验测定煤样煤颗粒粒径分布接近于对数正态分布,平均粒径为1 217μm,分布左偏;煤样随着颗粒的增大,颗粒的形状越不规则,导致按颗粒数量、颗粒投影面积、颗粒体积的统计差距较大;煤样的椭圆率分布曲线近似正态分布,圆度分布右偏较大;随着粒径的增大,粒形变化越大,研究煤样的吸附解吸等特性时需考虑粒形的影响。

Coal samples from Hexing Coal Mine in Yunnan Province were selected and 8 samples from 1 mm to 3 mm were measured by dynamic image method, each of which was 20 g. The experiment found that the dynamic image method measures the particle size distribution experiment with good repeatability. The minimum diameter of the Ferret and the diameter of the largest inscribed circle are basically the same according to the number of particles. The experimental determination of the particle size distribution of coal sample coal is close to the lognormal distribution, the average particle size is 1 217 μm, and the distribution is left-biased. As the increase of the particle size, the shape of the particle becomes more irregular, resulting in a larger statistical gap depending on the number of particles, the projected area of the particle, and the volume of the particle. The ellipse ratio distribution curve of the coal sample approximates a normal distribution, but the circularity distribution is relatively skewed. As the increase of particle size, the grain shape changes more so that the influence of particle shape should be considered in studying the characteristics of adsorption and desorption of coal samples.