Biological hydrogen production via dark fermentation: A holistic approach from lab-scale to pilot-scale

Biohydrogen is considered as fuel of future owing to its distinctive attribute for clean energy generation, waste management and high energy content. Suitable feedstock play important role for achieving high rate hydrogen production via dark fermentation process. In this regard, different organic wastes such as cane molasses, distillery effluent and starchy wastewater were examined as potential substrates for biohydrogen production by Enterobacter cloacae IIT-BT 08. Groundnut deoiled cake (GDOC) was considered as additional nutritional supplement to enhance biohydrogen yields. The maximum hydrogen yield of 12.2 mol H-2 kg(-1) CODremoved was obtained using cane molasses and GDOC as co-substrates. To further ensure reliability of the process, bench (50 L) and pilot scale (10000 L) bioreactors were customized and operated. The pilot scale study achieved 76.2 m(3) hydrogen with a COD removal and energy conversion efficiency of 18.1 kg m(-3) and 37.9%, respectively. This study provides an extensive strategy in moving from lab to pilot scale biohydrogen production thereby, providing further opportunity for commercial exploitation. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.