Effect of temperature on methane production from field-scale anaerobic digesters treating dairy manure
- Source:
- Waste management 2015 v.43 pp. 108-113
- ISSN:
- 0956-053X
- Subject:
- acclimation, anaerobic digesters, anaerobic digestion, dairy manure, digestion, energy, heat, methane, methane production, small farms, solids, temperate zones, temperature, waste management
- Abstract:
- Temperature is a critical factor affecting anaerobic digestion because it influences both system heating requirements and methane production. Temperatures of 35–37°C are typically suggested for manure digestion. In temperate climates, digesters require a considerable amount of additional heat energy to maintain temperatures at these levels. In this study, the effects of lower digestion temperatures (22 and 28°C), on the methane production from dairy digesters were evaluated and compared with 35°C using duplicate replicates of field-scale (FS) digesters with a 17-day hydraulic retention time. After acclimation, the FS digesters were operated for 12weeks using solids-separated manure at an organic loading rate (OLR) of 1.4kgVSm−3d−1 and then for 8weeks using separated manure amended with manure solids at an OLR of 2.6kgVSm−3d−1. Methane production values of the FS digesters at 22 and 28°C were about 70% and 87%, respectively, of the values from FS digesters at 35°C. The results suggest that anaerobic digesters treating dairy manure at 28°C were nearly as efficient as digesters operated at 35°C, with 70% of total methane achievable at 22°C. These results are relevant to small farms interested in anaerobic digestion for methane reduction without heat recovery from generators or for methane recovery from covered lagoon digesters.
- Agid:
- 61547
- Handle:
- 10113/61547
- https://doi.org/10.1016/j.wasman.2015.06.005