Magnetite-promoted direct interspecies electron transfer and its effect on anaerobic digestion of dairy effluent

Interspecies electron transfer in the anaerobic digestion (AD) process is usually mediated via hydrogen or formate as an electron carrier.However,in direct interspecies electron transfer (DIET),electrons from the oxidation of organic compounds are directly transferred to CO2 to yield CH4.This study was focused on the effect of supplementation with magnetite (Fe3O4),a conductive iron oxide,as a method to stimulate DIET activity,for AD of dairy effluent in continuous mode.Magnetite was beneficial to process stability as well as to methanogenic performance.The magnetite-supplemented reactor was significantly more resistant and resilient to process imbalance than the one without magnetite.Magnetic separation and recycling of effluent magnetite effectively supported the promoted DIET to maintain a certain level of enhanced AD performance,while avoiding addition of extra magnetite in continuous operation.No significant reduction in process performance was observed in the reactor with magnetite recycling compared to the one with continuously added with magnetite.A combination of microscopic,elemental,and molecular analyses suggested that the enhanced biomethanation was likely attributable to the DIET promoted via conductive magnetite particles.
Anaerobic digestion direct interspecies electron transfer magnetite microbial community structure
Gahyun Baek Jaai Kim Changsoo Lee
School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea
国际会议
The 15th IWA World Conference on Anaerobic Digestion( 第15届IWA世界厌氧大会)
北京
英文
491-494
2017-10-17(万方平台首次上网日期,不代表论文的发表时间)