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Biosolids

Fact Sheet: Multi-Stage Anaerobic Digestion

Anaerobic digestion is a naturally occurring biological process in which large numbers of anaerobic bacteria convert organic matter into methane and carbon dioxide (a mixture called biogas) in the absence of air. Anaerobic digestion stabilizes the organic matter in wastewater solids, reduces pathogens and odors, and reduces the total solids/sludge quantity by converting part of the volatile solids fraction to biogas.

The biosolids technology fact sheet for multi-stage anaerobic digestion of biosolids provides:

  • A description of multi-stage anaerobic digestion
  • Applicability to wastewater treatment plants
  • Advantages and disadvantages of multi-stage anaerobic digestion
  • Design criteria
  • Performance capabilities and data
  • Operation and maintenance information
  • Costs
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