초록 열기/닫기 버튼
This study was performed to test the feasibility of thermophilic (55oC) co-digestion of municipal sewage sludge andfood wastes. The management variables of co-digestion were the mixed ratios of municipal sewage sludge and food wastehydraulic retention times (HRTs). During the operation of thermophilic co-digestion, the reactor pH ranged from 7.0 to7.5 and the reactor alkalinity remained above 3,200 to 4,000 mg/L as CaCO3. The volatile fatty acids concentrationincreased as the HRT shortened from 20 days to 10 days and the mixture ratio increased to 1:4, but did not reach toxiclevels for co-digestion of sewage sludge and food wastes. Methane productivity increased gradually as the organic loadingrate increased. Maximum methane productivity reached 1.03v/v-d at an HRT of 10 days and at the mixture ratio of 1:4. The TVS removal efficiency decreased from 70.6% to 58.3% as the HRT shortened from 20 days to 10 days. TVS removalefficiency ranged from 57.0% to 77% during the entire operation. It is likely that thermophilic co-digestion of sewagesludge and food wastes is a very effective method both to environmentally treat food waste and to economically producegas for energy
