• Journal of Korean Society of Environmental Engineers
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• v.29 no.2
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• pp.184-191
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• 2007

Coal-, coconut- and wood-based activated carbons and anthracite were tested for an adsorption and biodegradation performances of nitrogenous chlorinated by-products such as chloropicrin, DCAN, DBAN and TCAN. In early stage of operations, an adsorption performance was a main mechanism for removal of nitrogenous chlorinated by-products, however as increasing populations of attached bacteria, the bacteria played a major role in removing nitrogenous chlorinated by-products in the activated carbon and anthracite biofilter. It was also investigated that the compounds were readily subjected to biodegrade. Whilst the coal- and coconut-based activated carbons were found most effective in adsorption of the compounds, the anthracite was worst in adsorption of the compounds. Highest populations and activity of attached bacteria were shown in the coal-based activated carbon. The populations and activity of attached bacteria decreased in the order: coconut-based activated carbon > wood-based activated carbon > anthracite. The attached bacteria were inhibited for removal of the compounds at temperatures below $10^{\circ}C$. The attached bacteria were more active at higher water temperatures$(20^{\circ}C\;<)$ but less active at love. water temperature$(10^{\circ}C\;>)$. The removal efficiencies of the compounds obtained using coal-, coconut- and wood-based activated carbons and anthracite were directly related to the water temperatures. In particular, water temperature was the most important factor for removal of the compounds in the anthracite biofilter because the removal of the compounds depended mainly on biodegradation. Therefore, the main removal mechanism of the compounds the main mechanism on the removal of the compounds using activated carbon was both adsorption and biodegradation by the attached bacteria. The observation suggests that using coal-based activated carbon is the best for removal of nitrogenous chlorinated by-products in the water treatment.