title: Effect of sulfide inhibition and organic shock loading on anaerobic biofilm reactors treating a low-temperature, high-sulfate wastewater.
abstract: To assess the long-term treatment of sulfate- and carbon-rich wastewater at low temperatures, anaerobic biofilm reactors were operated for over 900 days at 20 degrees C and fed wastewater containing lactate and sulfate. Results showed the reactors could be operated at 20 degrees C with a load rate of 1.3 g-chemical oxygen demand (COD)/L x d or less and a sulfur loading rate (SLR) of 0.2 g-S/L x d, with no significant deterioration in performance. With acclimation periods, load rates of 3.4 g-COD/L x d and SLR of 0.3 g/L x d could be tolerated. Effluent dissolved sulfide and hydrogen sulfide levels were approximately 600 and 150 mg-S/L, respectively, during this period. The effect of organic shock loading was also assessed. Reactors appeared to recover from one, but not two, lactate spikes of approximately 5000 mg-COD/L. Long-term stability was achieved in reactors containing large, stable populations of lactate- and propionate-degrading sulfate-reducing bacteria and aceticlastic methanogens.
authors.affiliation: Department of Civil and Environmental Engineering, University of Iowa, Iowa City, Iowa 52242-1527, USA.
authors.forename: Heather B
authors.initials: HB
authors.lastname: McDonald
authors.forename: Gene F
authors.initials: GF
authors.lastname: Parkin
mesh_terms: D000693:Anaerobiosis; D018441:Biofilms; D013440:Sulfides / Q000494:pharmacology*; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D013440:Sulfides; D014874:Water Pollutants, Chemical