Microalgae-biorefinery with cascading resource recovery design associated to dairy wastewater treatment.

The potential of microalgae for the treatment of dairy wastewater (DWW) was studied by integrating with bioethanol production. At the end of treatment, organic carbon removal was observed to be 90% with simultaneous removal of nutrients. Biomass concentration increased from 3rd day and reached to a maximum of 1.4 g L-1 by the end of cycle. The biomolecular composition of microalgae comprised of 38% carbohydrates, 15% proteins and 22% lipids. Reducing sugars extracted from deoiled microalgae showed highest percentage of glucose (54.12%) than other monomers. The reducing sugars obtained were utilized for the production of bioethanol via yeast fermentation using Saccharomyces cerevisiae. This resulted in the production of ethanol (3G) upto 116.2 mg g-1 with simultaneous decrease in reducing sugars upto 92 mg g-1. The results obtained indicate potential of microalgae to produce multiple biobased products in a biorefinery framework.