TY - JOUR
T1 - Sequential hydrotalcite precipitation and biological sulfate reduction for acid mine drainage treatment
AU - Yan, Su
AU - Cheng, Ka Yu
AU - Morris, Christina
AU - Douglas, Grant
AU - Ginige, Maneesha P.
AU - Zheng, Guanyu
AU - Zhou, Lixiang
AU - Kaksonen, Anna H.
PY - 2020/8
Y1 - 2020/8
N2 - Hydrotalcite precipitation is a promising technology for the on-site treatment of acid mine drainage (AMD). This technology is underpinned by the synthesis of hydrotalcite that can effectively remove various contaminants. However, hydrotalcite precipitation has only limited capacity to facilitate sulfate removal from AMD. Therefore, the feasibility of coupling biological sulfate reduction with the hydrotalcite precipitation to maximize sulfate removal was evaluated in this study. AMD emanating from a gold mine (pH 4.3, sulfate 2000 mg L−1, with various metals including Al, Cd, Co, Cu, Fe, Mn, Ni, Zn) was first treated using the hydrotalcite precipitation. Subsequently, biological treatment of the post-hydrotalcite precipitation effluent was conducted in an ethanol-fed fluidized bed reactor (FBR) at a hydraulic retention time (HRT) of 0.8–1.6 day. The hydrotalcite precipitation readily neutralized the acidity of AMD and removed 10% of sulfate and over 99% of Al, Cd, Co, Cu, Fe, Mn, Ni, Zn. The overall sulfate removal increased to 73% with subsequent FBR treatment. Based on 454 pyrosequencing of 16S rRNA genes, the identified genera of sulfate-reducing bacteria (SRB) included Desulfovibrio, Desulfomicrobium and Desulfococcus. This study showed that sulfate-rich AMD can be effectively treated by integrating hydrotalcite precipitation and a biological sulfate reducing FBR.
AB - Hydrotalcite precipitation is a promising technology for the on-site treatment of acid mine drainage (AMD). This technology is underpinned by the synthesis of hydrotalcite that can effectively remove various contaminants. However, hydrotalcite precipitation has only limited capacity to facilitate sulfate removal from AMD. Therefore, the feasibility of coupling biological sulfate reduction with the hydrotalcite precipitation to maximize sulfate removal was evaluated in this study. AMD emanating from a gold mine (pH 4.3, sulfate 2000 mg L−1, with various metals including Al, Cd, Co, Cu, Fe, Mn, Ni, Zn) was first treated using the hydrotalcite precipitation. Subsequently, biological treatment of the post-hydrotalcite precipitation effluent was conducted in an ethanol-fed fluidized bed reactor (FBR) at a hydraulic retention time (HRT) of 0.8–1.6 day. The hydrotalcite precipitation readily neutralized the acidity of AMD and removed 10% of sulfate and over 99% of Al, Cd, Co, Cu, Fe, Mn, Ni, Zn. The overall sulfate removal increased to 73% with subsequent FBR treatment. Based on 454 pyrosequencing of 16S rRNA genes, the identified genera of sulfate-reducing bacteria (SRB) included Desulfovibrio, Desulfomicrobium and Desulfococcus. This study showed that sulfate-rich AMD can be effectively treated by integrating hydrotalcite precipitation and a biological sulfate reducing FBR.
KW - Acid mine drainage
KW - Biological sulfate reduction
KW - Fluidized bed reactor
KW - Hydrotalcite precipitation
KW - Metal removal
KW - Mine water treatment
UR - http://www.scopus.com/inward/record.url?scp=85082700066&partnerID=8YFLogxK
U2 - 10.1016/j.chemosphere.2020.126570
DO - 10.1016/j.chemosphere.2020.126570
M3 - Article
C2 - 32443266
AN - SCOPUS:85082700066
SN - 0045-6535
VL - 252
JO - Chemosphere
JF - Chemosphere
M1 - 126570
ER -