Potential of using mixed culture resource recovery as a sustainable waste management strategy for industrial glycerin pitch

Conventional glycerin pitch (GP) waste management strategies contribute to severe environmental pollutions. Current resource recovery strategies only focus on using pure cultures or conversions through chemicals. Thus, in this study, the potential of using mixed cultures resource recovery as an alternative strategy in GP management was examined. A respiration inhibition test conducted shown that GP resource recovery using mixed cultures below 4.14 g C/L is recommended to avoid microbial inhibition. The culture enrichment reactor took 11 weeks to enter steady state operations where microorganisms were cultivated from activated sludge for resource recovery from GP. The enriched culture was capable of reducing the GP organic content by 66 % and produce 3.3 wt% of polyhydroxyalkanoates (PHA) and 149 mg/g extracellular polymeric substances (EPS). This study has demonstrated that GP treatment using mixed cultures is a promising alternative that also produces valuable products such as PHA and EPS.