The Biohydrogen Potential of Distillery Wastewater by Dark Fermentation in an Anaerobic Sequencing Batch Reactor

Abstract

Potential of biohydrogen production from distillery wastewater was studied by dark fermentation in an anaerobic sequencing batch reactor. The active volume of the reactor was 3.5 L. Anaerobic distillery sludge subjected to acid, chemical and heat-shock pre-treatment was used as inoculum. The reactor was operated at ambient temperature under dark condition with three cycles per day. Each cycle of operation consisted of four sequential steps: feed, react, settle and decant. The organic loading rate was increased by decreasing the hydraulic retention time from 96 to 72, 48, 36, and 24 h. Gas production trend and cumulative gas production were studied at various hydraulic retention times. The substrate degradation rate was found to vary from 12.65 to 23.52 kg_COD/m³/d at organic loading rates of 24 and 96 kg_COD/m³/d respectively. Experimental data showed the feasibility of biogas production along with substrate degradation with distillery wastewater as substrate.

Keywords:

• Dark fermentation
• Anaerobic sequencing batch reactor
• Biohydrogen
• Cycle length
• Hydraulic retention time