AUTHOR=Shu Chin-Hang , Jaiswal Rajan , Kuo Mu-do , Yu Bing-Hung 

TITLE=Enhancing Methane Production in a Two-Stage Anaerobic Digestion of Spent Mushroom Substrate and Chicken Manure via Activation of Sludge, Optimization of Temperature, and C/N Ratio

JOURNAL=Frontiers in Environmental Science

VOLUME=Volume 9 - 2021

YEAR=2022

URL=https://www.frontiersin.org/journals/environmental-science/articles/10.3389/fenvs.2021.810678

DOI=10.3389/fenvs.2021.810678

ISSN=2296-665X

ABSTRACT=Management of Spent mushroom substrate (SMS) is causing a global environmental concern due to tremendous increase in mushroom production globally.  Therefore, in this research, the performance of a two stage anaerobic co-digestion (TS-AD) of spent mushroom substrate and chicken manure was evaluated in terms of methane and biogas production, process stability with respect to single stage anaerobic digestion (SS-AD). Activation of anaerobic sludge using heat or air in the first stage at mesophilic temperature followed by thermophilic co-digestion with chicken manure in the second stage was investigated. TS-AD exhibited better performance and enhanced methane generation over SS-AD. The optimal temperatures were determined as 35˚C and 50˚C for first and second stage of TS-AD respectively. C/N ratio 10 was the most suitable for biogas and methane production. TS-AD with C/N ratio 10 and mesophilic digestion of SMS and sludge for three days at 35˚C followed by co-digestion of the first stage effluent with chicken manure at 50˚C was the optimized state producing 1359 mL biogas of which 614.42 mL was methane showing an increment by 59.44% in methane production as compared to SS-AD. TS-AD might be promising approach for utilization of SMS as feed stocks for biogas and methane production.