Monitoring of emissions from selected trades and industries in Hong Kong

Abstract

A survey on the concentration of organic and inorganic compounds emitted from various trades and industries in Hong Kong was performed to indicate the level of pollutants occurring in the factories, in the stacks and their dispersion into the environment. The results indicate that none of the organic or inorganic compounds present in the workplace exceed the TLV value for the factories during the visit in the two years period of study. However, the concentration of the chemistry compounds in the stack are found to be very high, with NH3 and HCl exceeding the emission limits. As the dispersion of pollutants in a highly populated place like Hong Kong is an important concern, the effect of prominent stationary sources on the nearby population were investigated qualitatively to establish their contribution to the pollution level at the receptor site in addition to the background pollutant level. Due to the lack of input meteorological data and the highly complex topology around most sites amongst high-rise buildings in Hong Kong, it is difficult to use advanced computer model dealing with complex terrain. Instead, a simple impaction formula was tested for its applicability in Hong Kong. The results indicate an over estimation of the experimental value. Nevertheless, it could be used to provide a rough estimate of the upper limit of the pollutant concentration at given receptor sites. The feasibility of assessing the contribution or different stationary sources to the particular collected at given receptor sites was studied and work is in progress to obtain a more comprehensive pollutant data inventory for the above assessment.