Long term control of fluorocarbon byproducts (CF_4 and C_2F_6) is of great interest to producers of Aluminium and to environmental agencies. These compounds are potent greenhouse gases due in part to their very long lifetimes in the upper atmosphere. Unisearch Associates, under contract to the Aluminium Association of Canada, has used their mobile tunable diode laser spectroscopy (TDLAS) laboratory to measure real time fluorocarbon emissions on site at numerous Aluminium plants. Two series of measurements were performed for six different plants in Quebec, one in 1993, and one recently concluded in 1999. The emissions from the centre work prebake (CWPB) plants were always the lowest. Environmentally, a significant trend was observed when comparing the 1993 and 1999 data. All six plants either reduced or maintained their levels of fluorocarbon production, with emission levels up to twenty times lower in 1999. Clearly the Aluminium industry in Canada is attentive to and successfully dealing with the fluorocarbon emission problem.
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