Featured Application: In Situ component and calorific value analysis of mixed coals in a thermal power plant. In Situ monitoring of the calorific value of coal has the advantage of reducing the amount of unburned carbon by injecting an appropriate amount of combustion air immediately to induce complete combustion. High sulfur concentrations cause severe environmental problems such as acid rain. In order to estimate the calorific value and measure the sulfur concentration, a new powerful technique for mixed coals was studied. Laser-induced breakdown spectroscopy (LIBS) does not require sample preparation. Several blended coals were used for the experiment to replicate the actual coal-fired power plant conditions. Two well-known data processing methods in near-infrared spectroscopy have been adopted to enhance the weak sulfur emission lines. The performance of the partial least square regression model was established by the parameters such as coefficient of determination, (Formula presented.), relative error, and root mean square error (RMSE). The RMSE average was compared with the results of previous studies. As a result, the values from this study were smaller by 6.02% for the calibration line and by 4.5% for the validation line in near-infrared spectroscopy. The RMSE average values for calorific values were calculated to be less than 1%.
Bibliographical noteFunding Information:
This work was partially supported by the Technology Innovation Program (or Industrial Strategic Technology Development Program-Development of technical support platform for welding material and process) (20017251, Development of laser welding automation system for electric coil joining system to manufacture electrical vehicle motors) funded by the Ministry of Trade, Industry & Energy (MOTIE, Korea). This work was partially supported by the National Research Foundation of Korea (NRF) entitled “Development of Coal Analyzing System Using Laser Induced Breakdown Spectroscopy for Clean Coal Power Plant” (No. NRF-2016R1D1A1B03935556). This work was also partially supported by the Basic Science Research Program through the National Research Foundation (NRF) of Korea entitled “NRF-2016R1D1A1B04934910”.
© 2022 by the authors.
- calorific value
- laser-induced breakdown spectroscopy (LIBS)
- multivariate data processing