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

Laser-induced breakdown spectroscopy (LIBS) was applied (1) near the superheater of an electric power generation boiler burning biomass, coal, or both; (2) at the exit of a glass-melting furnace burning natural gas and oxygen; and (3) near the nose arches of two paper mill recovery boilers burning black liquor. Difficulties associated with the high temperatures and high particle loadings in these environments were surmounted by use of novel LIBS probes. Echelle and linear spectrometers coupled to intensified CCD cameras were used individually and sometimes simultaneously. Elements detected include Na, K, Ca, Mg, C, B, Si, Mn, Al, Fe, Rb, Cl, and Ti.