Germanium interrelationship with ash and "toxic" elements in coal on the example of seam c4 of the "Samarska" mine field of Western Donbas

Abstract

The character and level of statistical relationship between the content of germanium and "toxic elements" in coal seam c4 of the "Samarska" mine and the main features of their distribution were established for the assessment of possible environmental risks during the selective processing of coal enriched with this element. It is proven that the correlation between germanium and all "toxic" elements is inverse and very weak. The existence of genetically different forms of germanium and arsenic, fluorine, mercury and beryllium was revealed. The research materials included analysis of 129 coal samples for the content of germanium, beryllium, fluorine, mercury and arsenic, performed in accredited state laboratories after 1981. The content of germanium, beryllium and fluorine was determined by quantitative emission spectral analysis, mercury and arsenic - by atomic absorption analysis. Samples were taken during the work of production enterprises and research organizations with the participation of the authors, using the furrow method of sampling in mine workings and from the core of wells from 1981 to 2018. For primary processing of geochemical data, STATISTICA 13.3 and IBM SPSS Statistics 22 programs were used to calculate basic statistical characteristics, including mean, standard error of the mean, median, kurtosis, mode, standard deviation, variance, minimum and maximum values, coefficient of variation, and sample skewness. To achieve the objectives of the study, correlation and regression analyzes were carried out using the functions available in Micromine - the leading professional mining and geological information system for 3D modeling, statistical data processing and mining planning. The presence of genetically different forms of germanium and arsenic, fluorine, mercury and beryllium in coal seam c4 of the Samarska mine was revealed. The polymodality of the distributions was established for all the considered components, while the displacement of the density of their distribution to the left was proved, except for germanium and beryllium. It was proven that the correlation between germanium and content of ash and all "toxic" elements (except beryllium) is inverse and very weak. Keywords: germanium, coal seam, mine field, toxic elements, regression analysis, frequency histograms, correlation analysis.