Abstract
UV-differential optical absorption spectrometer (DOAS) technique is considered as a promising technique to detect gaseous pollutants and was applied to conduct one-week continuous measurements in the Chinese Petroleum (CPC) refinery plant located in Lin Yuan industrial park of Kaohsiung, Southern Taiwan. With the combination of local meteorological information, including solar radiation, wind direction and speed, the results showed that the concentrations of aromatic compounds and formaldehyde (HCHO) were higher at night while the values of ozone, NO 2 and SO 2 were high during the day. The major source of aromatics was the aromatic extraction unit in the refinery while NO 2 and SO 2 were mainly emitted from chimneys with not very high average concentrations. Formaldehyde concentration was above 50 ppbv during night. There exists an apparent correlation between the variation of ground-level ozone concentration and photochemical reactions. The results indicate that in addition to benzene and toluene, ozone is a deleterious pollutant. The commercial DOAS system provides reliable information on distribution patterns of major air pollutants depending on their concentration levels in ambient air. © 2004 Elsevier Ltd. All rights reserved.