Abstract

The level of unburned carbon in fly ash is an important criteria for evaluating the combustion efficiencies of boilers, as well as the commercial value of the produced fly ash. In this work, an automated prototype laser-induced breakdown spectroscopy (LIBS) apparatus comprising an isokinetic sampler, a sample preparation module, and a LIBS module has been developed for possible application to power plants for on-line analysis of unburned carbon in fly ash without being affected by the type of coal burned. Emphasis is placed on the structure and operation of the LIBS apparatus, the optimum suction capacity selection, the analytical methods for estimation of the exact C line intensity, and the proper calibration model established for minimizing the matrix effects, which enable the minimization of matrix effects and obtaining more accurate compositional measurements. Good agreement has been found between the laboratory measurement results from the LIBS method and those from the traditional method. The measurement accuracy presented here for unburned carbon analysis is estimated to be 0.26%, while the average relative error is 3.81%.

Optimal boiler control through real-time monitoring of unburned carbon in fly ash by laser-induced breakdown spectroscopy

Miki Kurihara, Koji Ikeda, Yoshinori Izawa, Yoshihiro Deguchi, and Hitoshi Tarui
Appl. Opt. 42(30) 6159-6165 (2003)

Model of the diffuse reflectivity of fly ash and its application to an optical sensor system for the determination of carbon in fly ash

Alexander Schneider
Appl. Opt. 38(27) 5710-5723 (1999)

Quantitative carbon measurement in anthracite using laser-induced breakdown spectroscopy with binder

Tingbi Yuan, Zhe Wang, Lizhi Li, Zongyu Hou, Zheng Li, and Weidou Ni
Appl. Opt. 51(7) B22-B29 (2012)

Quantification of total carbon in soil using laser-induced breakdown spectroscopy: a method to correct interference lines

Gustavo Nicolodelli, Bruno S. Marangoni, Jader S. Cabral, Paulino R. Villas-Boas, Giorgio S. Senesi, Cléber Hilario dos Santos, Renan A. Romano, Aline Segnini, Yves Lucas, Célia R. Montes, and Débora M. B. P. Milori
Appl. Opt. 53(10) 2170-2176 (2014)

Laser-induced breakdown spectroscopy at high temperatures in industrial boilers and furnaces

Linda G. Blevins, Christopher R. Shaddix, Shane M. Sickafoose, and Peter M. Walsh
Appl. Opt. 42(30) 6107-6118 (2003)