Pilot-scale anaerobic digestion of screenings from wastewater treatment plants.

University of Lyon, INSA of Lyon, Lab. LGCIE, 20 av. A. Einstein, F-69621 Villeurbanne cedex, France.
Bioresource Technology (Impact Factor: 5.04). 12/2010; 101(23):9006-11. DOI: 10.1016/j.biortech.2010.06.150
Source: PubMed

ABSTRACT The anaerobic digestion of screenings from a municipal wastewater treatment plant was studied in a 90 L pilot-scale digester operated at 35 degrees C under semi-continuous conditions. In the first 4 weeks, a dry solids residence time of 28 days was applied, but the installation of inhibitory conditions was observed. Feeding was therefore suspended for 4 weeks to allow the digester to recover from inhibition, and then progressively increased up to a constant load of 6 kg of raw waste per week, corresponding to an average residence time of about 35 days of dry solids. At this stage, biogas production stabilized between 513 and 618 Nl/kg VS(added) per week, with methane contents around 61% v/v. The results of this work thereby supported the feasibility of (co-)digestion as a potential alternative treatment of screenings from municipal wastewater treatment plants.

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