고율 혐기성 처리 공정에서의 LCFA의 분해특성 및 저해 영향

Abstract

The synthetic wastewater containing major long-chain fatty acids (LCFA) was treated in bench-scale of two- and single- phase high-rate anaerobic systems for 10 months. LCFA did not cause any significant problem up to 1.21 ㎏ LCFA_m-COD/㎥/d in both systems. The removal efficiencies of COD and LCFA were above 90% and the methane conversion was above 75% of the theoretical value in both systems. However, the efficiencies of the singlephase system decreased at the LCFA mixture concentration above 1.40 ㎏ LCFA_m-COD/㎥/d while those of the two-phase system were still satisfactory. The partial degradation of unsaturated LCFA in acidogenesis might lead to the enhanced efficiencies in the two-phase system. However, the failure of the system was originated from the excess LCFA loading due to the sludge wash-out rather than the toxic effects of high concentration of LCFA. The sufficient inoculation and the prevention of biomass wash-out would be helpful for the successful high-rate anaerobic treatment of fat containing wastewater.