Dewater the digestate and recirculate part of the solids back to the biogas reactor!

Anaerobic digester units at wastewater treatment plants (WWTP) account for approximately half of the existing biogas production facilities in Sweden and their existing capacity can be used for more biogas production through co-digestion of energy-rich organic wastes. In this context, waste lipids are regarded as attractive co-substrates because of their high methane potential and energy density.

However, formation of long-chain fatty acids (LCFA) during anaerobic degradation of waste lipids and potential inhibitory effects on methanogenic activity make the use of waste lipids uncertain and challenging.

A new study from BRC shows that effluent solids recirculation improves microbial long-chain fatty acids degradation capacity, providing possibilities for co-digestion of larger amounts of waste lipids with municipal sludge.

Read more: “Effluent solids recirculation to municipal sludge digesters enhances long-chain fatty acids degradation capacity”