This analytical method offers a new way of measuring pentachlorophenol (PCP) in soil, wood, and water samples by gas chromatography and its hydrocarbon solvent by FT-IR spectroscopy. The distinctive feature of this method is that both the PCP and the oil are extracted from a single 1-g sample. They are first extracted from the wood or soil samples with a 1:1 mixture of Freon 113 and methanol using ultrasonication. An aliquot of the resulting organic phase is then added to an aqueous phase buffered at pH 9.2 with Na2HPC>4. The oil remaining in the organic phase is analyzed by FT-IR, whereas the PCP in the aqueous phase is acetylated by reaction with acetic anhydride, back-extracted in Freon 113, and injected into the gas chromatograph. Low-PCP-content water samples (<5 //g/L) are acidified and extracted in Freon 113, which is then added to the aqueous phase. High-PCP-content water samples (>5 µ g/L) are buffered and treated as the buffered aqueous phase. Extraction recoveries for the different matrices range from 94 to 115%. The absolute detection limits (3 ) for PCP and the hydrocarbon solvent are respectively 28 ng and 0.1 mg for a 1-g solid sample or a 100-mL volume of water sample. The PCP content of wood samples was compared with that obtained by neutron activation analysis and correlated with a 0.97 coefficient. The precision of the analytical method is better than 10% for both analytes. This analytical approach was successfully applied to the radial characterization of freshly treated poles for their PCP and oil contents.Pentachlorophenol (PCP) is widely used as a biocide in the wood preservation industry.* 1 It is dissolved in a hydrocarbon solvent such as oil and pressure-injected in the wood. The biocide-oil solution is present in the wood but also in the soil or water in the vicinity of wood-treatment plants. Also, it migrates out of the wood poles used by telephone companies and electrical utilities. In response to the environmental problems this creates, predictive software for evaluating the behavior of PCP and oil migrating from wood poles to the environment is under development at Hydro-Québec.
Ozone emission in hydro generators is a sign of surface partial discharge (PD) in the stator windings. Surface PD activity can take different forms: slot PD, corona at the junction of the slot semiconductive coating with the voltage grading coating outside the slot, PD between adjacent coils in the end-winding, PD between adjacent connections and surface tracking. An ozone concentration above the daily exposure limit, for which there is a health hazard for workers, was found at several locations in a 6-hydro generator plant. The ozone level in the vicinity of the generators was in the same range for all of them. This case study presents how this problem was identified and addressed.
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