A large depth of field LIBS measuring system for elemental analysis of moving samples of raw coal

Industrial applications of laser-induced breakdown spectroscopy: a review

“…A promising method for avoiding sampling and treatment of the coal and managing the variations in the lens-to-sample distance at the conveyor belt has been recently proposed by Redoglio et al 36 The method proposed by the authors allows, in principle, the measurement of the main parameters of coal (ash content and caloric value) without sampling by using a large depth of eld (more than 10 cm) LIBS system. A similar experimental setup has been realized and successfully tested by the authors of ref.…”

Atomic spectrometry update: review of advances in the analysis of metals, chemicals and functional materials

“…The corresponding average relative error of the predicted samples was signicantly reduced from 83% to 5.48%, 5.83-4.42%, and 5.4-3.68%, respectively. In an important development, Redoglio et al 44 presented the preliminary results of laboratory tests carried out on the analysis of moving samples of coal using laser induced breakdown spectrometry. An innovative LIBS system with a large depth of eld was designed to operate on-line in a coal red power plant.…”

Evaluation of femtosecond laser-induced breakdown spectroscopy system as an offline coal analyzer

“…Coal properties; ash content, volatile matter content, and calorific value, were predicted using SVM combined with PCA and the average relative error of prediction reduced from 8.3% to 5.48%, 5.83% to 4.42%, and 5.4% to 3.68%, respectively. On a laboratory level, Redoglio et al 7 , 8 designed a moving system comprised a 500 mm-diameter circular array to house coal samples and rotate at fixed speed. The optical system with a large depth-of-field mirror was utilized to overcome the changing in coal rocks’ height.…”