ERCo has developed a laser-based technology for rapid compositional measurements of batch, real-time sorting of cullet, & in-situ measurements of molten glass. This technology, termed LIBS (Laser Induced Breakdown Spectroscopy) can determine whether or not the batch was formulated accurately in order to control glass quality. It can also be used to determine if individual batch ingredients are within specifications. In the case of cullet feedstocks, the sensor can serve as part of a system to sort cullet by colour & ensure that it is free of contaminants. In-situ compositional measurements of molten glass are achieved through immersing a LIBS probe directly into the melt in a glass furnace. The technology has been successfully demonstrated in ERCO's LIBS laboratory for batch analysis, cullet sorting, & glass melt measurements. A commercial batch analyser has been operating in a PPG fiberglass plant since August 2004. LIBS utilises a highly concentrated laser pulse to rapidly vaporize and ionize nanograms of the material being studied. As the vapour cools, it radiates light at specific wavelengths corresponding to the elemental constitutents of the material. By collecting the radiated light with a spectrometer capable of resolving & measuring these wavelengths, the elemental composition of the sample is found.
