Defining manganese(II) removal processes in passive coal mine drainage treatment systems through laboratory incubation experiments

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• 作者：Fubo Luan ; Cara M. Santelli ; Colleen M. Hansel ; William D. Burgos
• 刊名：Applied Geochemistry
• 出版年：2012
• 出版时间：August, 2012
• 年：2012
• 卷：27
• 期：8
• 页码：1567-1578
• 全文大小：1018 K

文摘

Oxic limestone beds are commonly used for the passive removal of Mn(II) from coal mine drainage (CMD). Aqueous Mn(II) is removed via oxidative precipitation of Mn(III/IV) oxides catalyzed by Mn(II)-oxidizing microbes and Mn oxide (MnO_x) surfaces. The relative importance of these two processes for Mn removal was examined in laboratory experiments conducted with sediments and CMD collected from eight Mn(II)-removal beds in Pennsylvania and Tennessee, USA. Sterile and non-sterile sediments were incubated in the presence/absence of air and presence/absence of fungicides to operationally define the relative contributions of Mn removal processes. Relatively fast rates of Mn removal were measured in four of the eight sediments where 63-99 % of Mn removal was due to biological oxidation. In contrast, in the four sediments with slow rates of Mn(II) removal, 25-63 % was due to biological oxidation. Laboratory rates of Mn(II) removal were correlated (R² = 0.62) to bacterial biomass concentration (measured by phospholipid fatty acids (PLFA)). Furthermore, laboratory rates of Mn(II) removal were correlated (R² = 0.87) to field-scale performance of the Mn(II)-removal beds. A practical recommendation from this study is to include MnO_x-coated limestone (and associated biomass) from an operating bed as ¡°seed¡± material when constructing new Mn(II)-removal beds.