TY - JOUR
T1 - Managing the interactions between sulfate- and perchlorate-reducing bacteria when using hydrogen-fed biofilms to treat a groundwater with a high perchlorate concentration
AU - Ontiveros-Valencia, Aura
AU - Tang, Youneng
AU - Krajmalnik-Brown, Rosa
AU - Rittmann, Bruce
PY - 2014/5/15
Y1 - 2014/5/15
N2 - A groundwater containing an unusually high concentration (~4000μg/L) of perchlorate (ClO4-) and significant (~60mg/L) sulfate (SO42-) was treated with hydrogen (H2)-fed biofilms. The objective was to manage the interactions between sulfate-reducing bacteria (SRB) and perchlorate-reducing bacteria (PRB) by controlling the H2-delivery capacity to achieve ClO4- reduction to below the detection limit (4μg/L). Complete ClO4- reduction with minimized SO42- reduction was achieved by using two membrane biofilm reactors (MBfRs) in series. The lead MBfR removed >96% ClO4-, and the lag MBfR further reduced ClO4- to below the detection limit. SO42- reduction ranged from 10 to 60%, and lower SO42- reduction corresponded to lower H2 availability (i.e., lower H2 pressure or membranes with lower H2-delivery capacity). Minimizing SO42- reduction improved ClO4- removal by increasing the fraction of PRB in the biofilm. High SO42- flux correlated with enrichment of Desulfovibrionales, autotrophic SRB that can compete strongly with denitrifying bacteria (DB) and PRB. Increased SO42- reduction also led to enrichment of: 1) Ignavibacteriales and Thiobacteriales, sulfide-oxidizing bacteria that allow sulfur cycling in the biofilm; 2) Bacteroidales, heterotrophic microorganisms likely using organic sources of carbon (e.g., acetate); and 3) Spirochaetales, which potentially utilize soluble microbial products (SMPs) from autotrophic SRB to produce acetate.
AB - A groundwater containing an unusually high concentration (~4000μg/L) of perchlorate (ClO4-) and significant (~60mg/L) sulfate (SO42-) was treated with hydrogen (H2)-fed biofilms. The objective was to manage the interactions between sulfate-reducing bacteria (SRB) and perchlorate-reducing bacteria (PRB) by controlling the H2-delivery capacity to achieve ClO4- reduction to below the detection limit (4μg/L). Complete ClO4- reduction with minimized SO42- reduction was achieved by using two membrane biofilm reactors (MBfRs) in series. The lead MBfR removed >96% ClO4-, and the lag MBfR further reduced ClO4- to below the detection limit. SO42- reduction ranged from 10 to 60%, and lower SO42- reduction corresponded to lower H2 availability (i.e., lower H2 pressure or membranes with lower H2-delivery capacity). Minimizing SO42- reduction improved ClO4- removal by increasing the fraction of PRB in the biofilm. High SO42- flux correlated with enrichment of Desulfovibrionales, autotrophic SRB that can compete strongly with denitrifying bacteria (DB) and PRB. Increased SO42- reduction also led to enrichment of: 1) Ignavibacteriales and Thiobacteriales, sulfide-oxidizing bacteria that allow sulfur cycling in the biofilm; 2) Bacteroidales, heterotrophic microorganisms likely using organic sources of carbon (e.g., acetate); and 3) Spirochaetales, which potentially utilize soluble microbial products (SMPs) from autotrophic SRB to produce acetate.
KW - Biofilm
KW - Hydrogen
KW - Perchlorate-reducing bacteria
KW - Pyrosequencing
KW - QPCR
KW - Sulfate-reducing bacteria
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U2 - 10.1016/j.watres.2014.02.020
DO - 10.1016/j.watres.2014.02.020
M3 - Article
C2 - 24607522
AN - SCOPUS:84895746256
VL - 55
SP - 215
EP - 224
JO - Water Research
JF - Water Research
SN - 0043-1354
ER -