TY - JOUR
T1 - Continuous-mode acclimation and operation of lignocellulosic sulfate-reducing bioreactors for enhanced metal immobilization from acidic mining-influenced water
AU - Miranda, Evelyn M.
AU - Severson, Carli
AU - Reep, Jeffrey K.
AU - Hood, Daniel
AU - Hansen, Shane
AU - Santisteban, Leonard
AU - Hamdan, Nasser
AU - Delgado, Anca G.
N1 - Funding Information:
We thank SanTan Brewing Company, Chandler, Arizona, for providing spent beer grains, and Cajun Sugar Company, New Iberia, Louisiana for providing sugarcane bagasse. We also thank Dennis G. Grubb, currently with Jacobs, for facilitating the acquisition of the sugarcane bagasse (from Cajun Sugar Company), Skanda Vishnu Sundar for assistance with total carbon analyses, and Caleb McLaughlin for assistance in determining the lignocellulosic composition of materials. This work was funded by Freeport-McMoRan Inc. and National Science Foundation (NSF) Engineering Research Center for Bio-mediated and Bio-inspired Geotechnics (CBBG) under NSF CA No. EEC-1449501. EMM was partially supported by the Western Alliance to Expand Student Opportunities (WAESO) Louis Stokes Alliance for Minority Participation (LSAMP) Bridge to Doctorate (BD), NSF Cooperative Agreement HRD-1702083. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect those of the NSF.
Funding Information:
We thank SanTan Brewing Company, Chandler, Arizona, for providing spent beer grains, and Cajun Sugar Company, New Iberia, Louisiana for providing sugarcane bagasse. We also thank Dennis G. Grubb, currently with Jacobs, for facilitating the acquisition of the sugarcane bagasse (from Cajun Sugar Company), Skanda Vishnu Sundar for assistance with total carbon analyses, and Caleb McLaughlin for assistance in determining the lignocellulosic composition of materials. This work was funded by Freeport-McMoRan Inc. and National Science Foundation (NSF) Engineering Research Center for Bio-mediated and Bio-inspired Geotechnics (CBBG) under NSF CA No. EEC-1449501 . EMM was partially supported by the Western Alliance to Expand Student Opportunities (WAESO) Louis Stokes Alliance for Minority Participation (LSAMP) Bridge to Doctorate (BD), NSF Cooperative Agreement HRD-1702083. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect those of the NSF.
Publisher Copyright:
© 2021 The Authors
PY - 2022/3/5
Y1 - 2022/3/5
N2 - Lignocellulosic sulfate-reducing bioreactors are an inexpensive passive approach for treatment of mining-influenced water (MIW). Typically, microbial community acclimation to MIW involves bioreactor batch-mode operation to initiate lignocellulose hydrolysis and fermentation and provide electron donors for sulfate-reducing bacteria. However, batch-mode operation could significantly prolong bioreactor start-up times (up to several months) and select for slow-growing microorganisms. In this study we assessed the feasibility of bioreactor continuous-mode acclimation to MIW (pH 2.5, 6.5 mM SO42−, 18 metal(loid)s) as an alternate start-up method. Results showed that bioreactors with spent brewing grains and sugarcane bagasse achieved acclimation in continuous mode at hydraulic retention times (HRTs) of 7–12-d within 16–22 days. During continuous-mode acclimation, extensive SO42− reduction (80 ± 20% –91 ± 3%) and > 98% metal(loid) removal was observed. Operation at a 3-d HRT further yielded a metal(loid) removal of 97.5 ± 1.3 –98.8 ± 0.9% until the end of operation. Sulfate-reducing microorganisms were detected closer to the influent in the spent brewing grains bioreactors, and closer to the effluent in the sugarcane bagasse bioreactors, giving insight as to where SO42− reduction was occurring. Results strongly support that a careful selection of lignocellulose and bioreactor operating parameters can bypass typical batch-mode acclimation, shortening bioreactor start-up times and promoting effective MIW metal(loid) immobilization and treatment.
AB - Lignocellulosic sulfate-reducing bioreactors are an inexpensive passive approach for treatment of mining-influenced water (MIW). Typically, microbial community acclimation to MIW involves bioreactor batch-mode operation to initiate lignocellulose hydrolysis and fermentation and provide electron donors for sulfate-reducing bacteria. However, batch-mode operation could significantly prolong bioreactor start-up times (up to several months) and select for slow-growing microorganisms. In this study we assessed the feasibility of bioreactor continuous-mode acclimation to MIW (pH 2.5, 6.5 mM SO42−, 18 metal(loid)s) as an alternate start-up method. Results showed that bioreactors with spent brewing grains and sugarcane bagasse achieved acclimation in continuous mode at hydraulic retention times (HRTs) of 7–12-d within 16–22 days. During continuous-mode acclimation, extensive SO42− reduction (80 ± 20% –91 ± 3%) and > 98% metal(loid) removal was observed. Operation at a 3-d HRT further yielded a metal(loid) removal of 97.5 ± 1.3 –98.8 ± 0.9% until the end of operation. Sulfate-reducing microorganisms were detected closer to the influent in the spent brewing grains bioreactors, and closer to the effluent in the sugarcane bagasse bioreactors, giving insight as to where SO42− reduction was occurring. Results strongly support that a careful selection of lignocellulose and bioreactor operating parameters can bypass typical batch-mode acclimation, shortening bioreactor start-up times and promoting effective MIW metal(loid) immobilization and treatment.
KW - Acid mine drainage
KW - Bioremediation
KW - Lignocellulose
KW - Spent brewing grains
KW - Sugarcane bagasse
KW - Sulfate-reducing bacteria
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U2 - 10.1016/j.jhazmat.2021.128054
DO - 10.1016/j.jhazmat.2021.128054
M3 - Article
C2 - 34986575
AN - SCOPUS:85121131116
VL - 425
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
SN - 0304-3894
M1 - 128054
ER -