Protein substrate supporting microbial granulation during anaerobic digestion in saline conditions. Saline UASB granules

Anaerobic digestion is a sustainable option to treat saline industrial wastewater, because of high biomass retention and methane production. The major challenge in saline conditions is to promote and maintain microbial aggregates such as granules into the reactor. Recently, microbial granules were obtained in saline (20 g/L Na+) upflow anaerobic sludge blanket (UASB) reactors when feeding the biomass with glucose, acetate, and tryptone in a 3:2:1 COD ratio as substrate. When removing tryptone, a biofilm formed instead of granules.