Anaerobic Digestion (Biogas)

Anaerobic digestion (AD) is a process in which organic matter from wet organic wastes (i.e. liquid manure, food processing wastes, etc.) is converted into methane by bacteria in the absence of oxygen. The methane is then collected and may be used to generate combined heat and power (CHP) or renewable methane fuel (RNG). In addition, the AD process creates potentially valuable by-products (i.e. fibrous solids/peat moss replacement and liquid wastewater rich in bio-available nutrients) while also alleviating key environmental concerns. These include reduction in odor, indicator pathogens, and greenhouse gas emissions as compared to non-AD baselines.

CSANR views AD as important technology for organic management but more importantly as a core unit operation in a grander vision of a bio-refinery. Within the bio-refinery approach multiple wastestreams are collected, separated and selectively treated for more efficient processing while also harnessing interconnected synergies and production of multiple co-products and revenue streams.  CSANR has supported extensive efforts in improving AD technology for:

  • multiple organic wastes,
  • co-digestion of manure with outside organics,
  • development and demonstration of novel nutrient recovery technologies for production of concentrated nutrient co-products,
  • development and demonstration of novel biogas purification systems,
  • integration of pyrolysis/chars within an AD platform,
  • reporting of reliable techno-economic and feasibility studies related to farm-based AD projects, and
  • technical/extension/outreach support for farmers, rural communities, project developers, and engaged agencies.

See also our Small-Scale Biogas page.

Featured Anaerobic Digestion Publications

Additional Anaerobic Digestion Publications

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