Strategies for the valorisation of a protein-rich saline waste stream into polyhydroxyalkanoates (PHA)

Saline Mussels Cooking Wastewater was valorised to produce PHA with Mixed Microbial Cultures (MMC). Due the high protein content (1.8–5.7 g CODPROT/L), accumulating capacity below 10%, so several strategies were tested. In acidification unit, Na(HCO3) added, increasing conversion into Volatile Fatty Acids (VFA) from 10.3% 69.2% and subsequent accumulation 6.9 14.7%. enrichment incorporation of a settling stage after feast phase provoked shift in proteins’ oxidation famine phase, where nitrogen released is used by MMC for growth. This increased biomass concentration tolerated COD (from 1.6 4.2 VSS/L 2.2 4.38 COD/L). Finally, varying proteins/VFA ratio acclimation proteins allowed 8.8 41.5%.