细粒煤粒度分布特性的研究

Studies of Size Distribution Characteristics of Fine Coal

利用常见粒度分布模型和广义正态分布模型,对18组细粒煤筛分数据进行了拟合。拟合结果表明,广义正态分布模型比正态分布模型和对数正态分布模型更适于描述细粒煤的粒度分布特性,但其拟合效果不如Rosin-Rammler（R-R）模型,各模型按对18组数据拟合结果的R2Adj（调整的拟合优度）之和由大到小依次为：R-R模型〉广义正态分布模型〉Alfred模型〉G-S模型〉对数正态模型〉正态分布模型。通过对各组细粒煤筛分数据和拟合结果的分析,提出了A、B、C和D 4类细粒煤粒度分布,讨论了各分布模型对4类粒度分布的适应情况,并论述了4类粒度分布在评价细粒煤分级效果和分析粒度效应对重选影响中的应用。针对液固分选流化床的典型入料粒度范围,分析了0.25-1mm细粒煤粒度分布特点,确定出在描述0.25-1mm细粒煤粒度分布时,R-R模型中两个参数存的二次函数关系。

The mathematical characteristics of several size distribution models were discussed and fitting tests were performed using these models on eighteen sets of fine coal screening data. Results of fitting tests implied that Rosin Rammler model is more proper to describe the size dis tribution of fine coal than general normal distribution model. The order of these models as the ad justed R2Adj descends is： Rosin-Rammler （R-R） model）〉general normal distribution model （normal distribution model with a coefficient of skewness）〉Alfred model〉GaudinSchuhmann （G S） model〉logarithmic normal distribution model〉normal distribution model. Four size distribution forms of fine coal were introduced and the adaptability of the size distribution models to these four forms was analyzed. The applications of the four forms in evaluating the classification efficiency of fine coal and analyzing the impacts of size effects on gravity separation were discussed in detail. Then, the size distribution characteristics of 0.25-1 mm fine coal, which is the typical size range 0.25-1 mm fine coal was obtained.