• 한국지하수토양환경학회지:지하수토양환경
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• 제15권4호
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• pp.30-38
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• 2010

This study was conducted to determine the potential applicability of slowly released molasses (SRM) to treat nitratecontaminated groundwater. SRM was made by dispersing molasses in hydroxy propyl methyl cellulose-silicamicrocrystalline cellulose matrix. Column test indicated that SRM could continuously release molasses with slowly decreasing release rates of $64.6mg-COD/L{\cdot}h$ up to 65 hrs, $12.1mg-COD/L{\cdot}h$ up to 215 hrs, and $4.4mg-COD/L{\cdot}h$up to 361 hrs. A batch test using an isolated indigenous heterotrophic denitrifier Pseudomonas sp. KY1 having nitrite reductase (nirK) and liquid molasses demonstrated that the bacterium decreased 100 mg-N/L of nitrate to less than 10 mg-N/L at the C/N ratio of 10/1 in 48 hours. In a Pseudomonas sp. KY1-attached Ottawa sand column which continuously received molasses from a SRM-containing reservoir, the bacterium successfully removed nitrate from 20 mg-N/L to 3 mg-N/L during the 361 hours of column operation. The results showed the possibility that SRM can be used as a reliable, longterm extra carbon source for indigenous heterotrophic denitrifiers.