Performance evaluation of self-designed Nickel oxide/Biochar nano-magnetic coating reactor for anaerobic digestion of corn stover

Considering the issues of low methane yield and high energy consumption in traditional anaerobic digestion (AD) systems. This study developed a novel nano-magnetic coated reactor by depositing nickel oxide/biochar (NiO/B) onto the reactor surface and installing N-S alternately arranged magnets on the agitator blades, thereby introducing eddy currents into the AD system. The reactor achieved a 32.61% increase in gas production compared to conventional fermentation reactors at optimal organic loading rates.The dominant bacterial strains, including Streptococcus, DMER64, and Candidatus_Methanomethylicus, obviously improved direct interspecies electron transfer (DIET) efficiency and methane metabolism capacity in the system. The novel nanomagnetic-coated reactor developed in this study enhances methane yield through an endogenous electric field while reducing energy consumption, exploring new strategies for multidisciplinary collaboration in biogas applications.