Synergistic Impact of Gas-Looping, Biocatalyst and Co-Substrate on Acidogenic Metabolism : Fatty Acid Enrichment and Insitu Biogas Upgradation from Spent Wash

Waste valorization and biogas upgradation towards biobased products generation are promising strategieswhich have potential to deal with the issue of greenhouse gas emissions reduction and attaining sustainability. Volatile fatty acids (VFAs), biohydrogen (bio-H 2 ) and methane (CH 4 ) are known for their enormous application in the sector of commodity chemicals production and bioenergy.This study presents an insight of generating bioproducts from spent wash considering insitu biogas looping and critical parameters for enhanced productivity of these products. Prospective of co-substrate fermentation using food waste and spent wash was also evaluated. The results obtained from the study indicated the feasibility of pretreated biocatalyst for VFA and bio-H 2 production while untreated biocatalyst for CH 4 production which were further enhanced by insitu biogas looping. Pretreated inoculum and biogas looping resulted in VFAs production yield of 0.59 gVFA/gCOD. In addition, VFA production yield of 0.63 gVFA/gCOD was achieved by co-substrate fermentation.PNGC and UGC exhibited highest gaseous production of 2357.46 NmL(bio-H 2 ) and 1554.3 NmL(bio-CH 4 ), respectively. The positive impact of pretreatment of biocatalyst, insitu biogas looping and co-substrate fermentation provides the scope for sustainable generation of biobased products from spent wash