Monitoring the sulfur content of coal

Abstract

Information regarding the sulfur content of the coal is required not only in metallurgy but also when burning coal as a fuel. The traditional method of determining the sulfur content of coal is unsuitable for large-scale monitoring of processes because it is laborious and not sufficiently reliable. Nuclear-physics methods are free of those problems. However, satisfactory precision of the results is only possible with relatively constant composition of the coal or when the matrix effect due to fluctuations in the composition is taken into account. In the present work, the composition of coal is studied by correlation and regression analysis of the ash composition in coal from different deposits. The correlation coefficients between the main ash components (Al₂O₃, SiO₂, SO₃, CaO, and Fe₂O₃) are calculated. For the example, of coal from Kazakhstan and the Minusinsk Basin, statistically significant correlations are established between the contents of sulfur and calcium in the coal; the correlation coefficient is 0.75–0.93. No significant and consistent correlations are found between other ash components. These findings permit optimal development of nuclear-physics methods of monitoring the sulfur content of coal—specifically, in improving the precision of the analysis by taking account of the matrix effect due to redistribution of the mineral components.