Interaction of short-chain fatty acids carbon source on denitrification

ABSTRACTShort-chain fatty acids (SCFAs) could be obtained from organic waste anaerobic digestion. The ability and interaction of different SCFAs on denitrification were investigated in this study. Two kinds of SCFAs (acetate and propionate with 5 different ratios) and 4 kinds of SCFAs (acetate, propionate, butyrate and valerate with 10 different ratios) were evaluated. Using acetate (Ac) and propionate (Pr) as carbon sources, the highest nitrate removal efficiency of 97.5% was obtained. When using the mixture of acetate (Ac), propionate (Pr), butyrate (Bu) and valerate (Va) as the carbon source, the highest nitrate removal efficiency obtained was 92.0%. The denitrification performance was affected significantly by different kinds and proportions of SCFAs. In addition, nitrite accumulation and chemical oxygen demand consumption for different contents of SCFAs were also analyzed.