Simultaneous detection of multi-elements in coal based on laser-induced breakdown spectroscopy

In order to achieve rapid and simultaneous quantitative detection of C, H, S in coal, laser-induced breakdown spectroscopy(LIBS) was used. A Nd:YAG solid-state laser with wavelength of 1064nm was used as excitation source. Nine kinds of national standard coal samples were ablated in air environment. Combined with partial least squares regression, the spectrum with wavelength ranges of 188.885nm~308.008nm and 655nm~660nm were selected to detect C, H and S non-metallic elements in coal simultaneously. The correction model and prediction model data of partial least squares regression were obtained. The theoretical analysis and experimental verification were carried out. The results show that, determination coefficients R² of the predicted and real concentrations of C, H and S are 0.9421, 0.9894 and 0.9840. Root mean square error of calibration is 2.2772, 0.2356 and 0.1678. Average relative error is 2.6348%, 7.1185% and 8.8600%. LIBS combined with partial least squares regression can be used to quantitatively detect non-metallic elements in coal.