Talk:Thermophilic digester

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I found this site: [USP] with this text:"he technical feasibility of a combined thermophilic anaerobic-aerobic biological reactors configuration was evaluated in this work using a synthetic unbleached pulp mill effluent. These industries introduce effluent with temperature greater 40 Celsius degrees and the treatment would eliminate the need of cooling that is required for the mesophilic range, reducing the costs. The reactors were inoculated with mesophilic sludge with gradual adaptation to the termophilic condition. In the mesophilic range (37.5 to 42.5 Celsius degrees) the efficiency of the combined system was (69±3)%, with the higher efficiency in the anaerobic reactor (56±7)%. After the reactors reached apparent steady state regime the temperature was gradually increased from 42.5 to 52 Celsius degrees. The system efficiency ranged from 57% to 88%. The percentage of methane in the biogas decreased with the increase in temperature, from 77% to values below the detection limit of the chromatographic measurement used in this work. The anaerobic efficiency was low and the reactor accumulated fatty acid, mostly acetic. The aerobic reactor presented higher efficiency removal of COD but the mixed liquor concentration was lower. After adjustment in the hydraulic retention time of both reactors, with the UASB operating with 24 hours HRT and the aerobic with 8 hours HRT, the reactors operated in the temperature range of 52 to 57 Celsius degrees during 85 days. The overall removal efficiency ranged from 54% to 70%. The efficiency of the UASB reactor remained lower while the aerobic reactor presented good performance, with COD removal efficiency in the range of 3% to 35%, respectively. The mixed liquor VSS concentration increased with the increase in temperature from 122 mg/L to 2940 mg/L. In thermophilic temperature there was predominance of Methanosaetas sp and baccilus in the anaerobic reactor, without significant differentiation of morphology in comparison with the mesophilic temperature. In the aerobic reactor there was differentiation in temperature of 42.5 Celsius degree and baccilus, cocus and filamentous predominated in the thermophilic temperature. These results indicated the feasibility of the thermophilic treatment but other experiments are needed before industrial application of this process ."Agre22 (talk) 02:14, 12 September 2009 (UTC)agre22