ArticleZheng X, Zhou W, Min B, Zhou Y, Xie L.
Bioresour Technol. 2023 Sep;384:129248.
A novel horizontal rotary bioreactor was developed for upgrading biogas from coke oven gas at extreme-thermophilic condition. The introduction of CO decreased the outlet methane content from 80% to 50% due to insufficient H2. This hindrance was overcome by increasing the proportion of incoming hydrogen, coupled with a prolonged gas retention time from 24 to 72 h, leading to a restoration of methane content to 91.6%. Notably, CO and CO2 exhibited a competitive relationship to hydrogen, which was determined by their contents. The substitution of Methanothermobacter for Methanobacterium as the dominant genus was observed at 70 °C, with relative abundance exceeding 98%. Incorporation of CO increased bacteria diversity and fostered a syntrophic relationship between the bacterial community and M. thermautotrophicus. This study provides both theoretical basis and practical support for biogas upgrading from coke oven gas using a biofilm reactor, thus aiding its future industrialization prospects.