Cohesive strategy and energy conversion efficiency analysis of bio-hythane production from corncob powder by two-stage anaerobic digestion process

Abstract

In order to maximize the substrate conversion, co-production of hydrogen and methane from two-stage anaerobic digestion has attracted wide attention. In two-stage fermentation process, the cohesive strategy is considered as a key indicator for bio-hythane yield. In this work, corncob powder was utilized as raw material. The pH of fermentative broth, bio-hythane yield, gas production rate and energy conversion efficiency were taken as indexes. Under the directional control of bio-chemical reaction process, the effects of diverse coupling time nodes on the fermentation process and the bio-hythane co-production potential were investigated. The results showed that when the coupling time node was 48 h, hydrogen production potential and methane production potential were 22.29 mL/g TS and 141.14 mL/g TS, respectively. The hydrogen content in the bio-hythane was 13.64% which satisfied the hydrogen concentration requirement, and the energy conversion efficiency was 27.6%.

Keywords: Bio-hythane production; Cohesive strategy; Coupling time node; Energy conversion efficiency; Two-stage anaerobic digestion.