화학공학소재연구정보센터
Bioresource Technology, Vol.282, 202-210, 2019
Weak magnetic field significantly enhances methane production from a digester supplemented with zero valent iron
Weak magnetic field (WMF) provided by a magnet was proposed to enhance CH4 production from a swine manure-fed digester supplemented with micron-sized zero valent iron (ZVI). Compared to the control without ZVI addition and WMF application (R-Control), treatments that included ZVI only (R-ZVI) and coupled WMF with ZVI (R-ZVI/WMF) increased the CH4 production by 77.0% and 124.5%, respectively. As evidenced by the elevated levels of total soluble iron, WMF apparently promoted the corrosion of ZVI, providing extra H-2 for hydrogenotrophic methanogenesis and creating a more reductive environment to reduce propionic-type fermentation. Microbial analysis results revealed that the relative abundance of Methanothrix (capable of accepting electrons) in R-ZVI/WMF were 75.1% higher than that in R-ZVI. Essentially, WMF application promoted the direct interspecies electron transfer-based methanogenesis by (1) providing more electrons as the direct substrate, and (2) inducing Lorentz force to facilitate the mass transfer between the released electrons and the methanogens.