Single-stage fermentation process for high-value biohythane production with the treatment of distillery spent-wash.

ABSTRACT

The current communication reports the development of a single-stage biosystem for biohythane production from wastewater treatment. A semi-pilot scale bioreactor with 34 L capacity was used for this study. Maximum biohythane production of 147.5 ± 2.4 L was observed after five cycles of operation with production rate of 4.7 ± 0.1L/h. The biohythane composition (H2/(H2+CH4)) varied from 0.60 to 0.23 during stabilized fifth cycle of operation. During each cycle of operation, higher H2 fraction was noticed within 12h of cycle period followed by CH4 production for rest of operation (36 h). During biohythane production, COD removal efficiency of 60 ± 5% (SDR, 29.0 ± 1.9 kg CODr/m(3)-day) was also achieved. The synergistic function of volatile fatty acids (VFA) production and consumption during process in hybrid biosystem played vital role on the composition of biohythane. The single-stage biosystem facilitates production of high valued and cost efficient biofuel (biohythane) with fewer controls than individual acidogenic and methanogenic processes.