Batch anaerobic digestion of dairy manure was performed at low (25ºC), mesophilic (37ºC), and thermophilic (52.5ºC) temperatures to determine the influences of temperatures on biogas production. The experiment was runfor 76, 40 and 29 days at 25, 37, and 52.5ºC, respectively. The biogas production was measured daily at each temperature. To estimate the solid reductions, we measured total solids (TS) andvolatile solids (VS) over time. The biogas production at 52.5ºCand 37ºC were 49 and 17 times higher than that at 25ºC. Over incubation periods, the TS reduction at 25, 37, and 52.5ºC were5.6, 57, 34%, respectively. The VS reductions were 127, 58.4, 42.5%, respectively. At 25 and 37 ºC, pH was reduced, while at52.5 ºC pH was increased. The Oxidation Reduction Potential (ORP) values at 37 and 52.5ºC were negative over the incubation period. But at 25ºC, however, the ORP values were positive after Day 19. Findings from this study are useful for enhancing anaerobic digesters’ performance.
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