title: Influence of a supplemental carbon source on anaerobic dechlorination of pentachlorophenol in granular sludge.
abstract: Anaerobic dechlorination of pentachlorophenol (PCP) was studied in two upflow anaerobic sludge blanket reactors. One reactor received glucose (0.9 g liter-1) as an additional carbon source; the other one served as a control. The concentration of PCP in the medium was 4.5 and 3.0 mg liter-1 in the experimental and control reactors, respectively. The reactors were inoculated with granular sludge previously grown on sugar-containing wastewater. After 10 months of continuous operation, the removal of PCP was 99% in the glucose-amended reactor, whereas the removal in the control reactor varied between 32 and 77%. Furthermore, 94% of the PCP was completely dechlorinated in the glucose reactor compared with a maximum of 20% in the control reactor. In the same period, the amount of biomass in the glucose reactor had increased by approximately 150% compared with that in the control reactor, where no growth of the sludge bed occurred. Batch culture activity tests showed that the addition of glucose had a stimulatory effect on the dechlorination rate of PCP per gram of volatile solids. This indicated that the better performance of the glucose-amended reactor was due to a higher concentration of biomass and a direct stimulatory effect of glucose on the dechlorination rate. The pattern of dechlorination of PCP showed that an initial para cleavage was followed by two ortho cleavages.
authors.affiliation: Department of Biotechnology, Technical University, Lyngby, Denmark.
authors.forename: H V
authors.initials: HV
authors.lastname: Hendriksen
authors.forename: S
authors.initials: S
authors.lastname: Larsen
authors.forename: B K
authors.initials: BK
authors.lastname: Ahring
mesh_terms: D000693:Anaerobiosis; D001711:Biotransformation; D002244:Carbon / Q000378:metabolism*; D002713:Chlorine / Q000378:metabolism; D015394:Molecular Structure; D010416:Pentachlorophenol / Q000737:chemistry / Q000378:metabolism*; D012722:Sewage; D012988:Soil Microbiology
chemical_list: D012722:Sewage; D002713:Chlorine; D002244:Carbon; D010416:Pentachlorophenol