Application of Laser-Induced Breakdown Spectroscopy to Coal-Fired Power Plants and Soil Contaminants On-line Monitoring

Abstract

Abstract:

A self-designed laser-induced breakdown spectroscopy (LIBS) equipment with self-cleaning system for on-line coal quality monitoring was introduced. By using the device, automatic sampling can be realized, and automatic real-time quantitative analysis of the elements of C, Ca, Mg, Ti, Si, H, Al, Fe, S in pulverized coal of coal transportation pipeline can be accomplished and be converted into industrial analysis (gross calorific value and coal ash) results. An automated prototype LIBS apparatus has been developed for possible application to power plants for on-line analysis of unburned carbon (UC) content in fly ash. A new mathematical process is proposed to distinguish C line from Fe line, and the second-order polynomial multivariate inverse regression is utilized to establish the calibration model and minimize the matrix effects, with the accuracy of carbon content measurement to be 0.26%. Finally, portable LIBS device for soil contaminants in situ detection is reviewed, which can accomplish fast qualitative analysis of heavy metal in soil.

Key words: laser-induced breakdown spectroscopy, coal quality monitor, proximate analysis, unburned carbon in fly ash, multivariate regression, soil contaminant

CLC Number:

O433.5

HU Zhi-Yu, ZHANG Lei, YIN Wang-Bao, MA Wei-Guang, DONG Lei, JIA Suo-Tang. Application of Laser-Induced Breakdown Spectroscopy to Coal-Fired Power Plants and Soil Contaminants On-line Monitoring[J]. Journal of Atmospheric and Environmental Optics, 2013, 8(1): 26-35.

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