title: Effect of pH on nitrate and selenate reduction in flue gas desulfurization brine using the H2-based membrane biofilm reactor (MBfR).
abstract: Increased tightening of air regulations is leading more electric utilities to install flue gas desulfurization (FGD) systems. These systems produce brine containing high concentrations of nitrate, nitrite, and selenate which must be removed before discharge. The H2-based membrane biofilm reactor (MBfR) was shown to consistently remove nitrate, nitrite, and selenate at high efficiencies. The maximum selenate removal flux reached 362 mgSe m(-2)d(-1) and was higher than that observed in earlier research, which shows continual improvement of the biofilm for selenate reduction. A low pH of 6.8 inhibited precipitation when treating actual FGD brine, yet did not inhibit removal. SO4(2-) was not removed and therefore did not compete with nitrate, nitrite, and selenate reduction for the available H2.
authors: Center for Environmental Biotechnology, Biodesign Institute at Arizona State University, P.O. Box 875701, Tempe, AZ 85287-5701, USA. steppen@asu.edu
authors: Steven W
authors: SW
authors: Van Ginkel
authors: Ziming
authors: Z
authors: Yang
authors: Bi-o
authors: BO
authors: Kim
authors: Mark
authors: M
authors: Sholin
authors: Bruce E
authors: BE
authors: Rittmann
mesh_terms: D001673:Biodegradation, Environmental; D018441:Biofilms / Q000254:growth & development*; D019149:Bioreactors / Q000382:microbiology*; D004867:Equipment Design; D006863:Hydrogen-Ion Concentration; D008567:Membranes, Artificial; D008962:Models, Theoretical; D009566:Nitrates / Q000302:isolation & purification*; D010084:Oxidation-Reduction; D064586:Selenic Acid; D018036:Selenium Compounds / Q000302:isolation & purification*; D013458:Sulfur Dioxide / Q000302:isolation & purification*; D018508:Water Purification / Q000295:instrumentation / Q000379:methods*
chemical_list: D008567:Membranes, Artificial; D009566:Nitrates; D018036:Selenium Compounds; D013458:Sulfur Dioxide; D064586:Selenic Acid