title: The biodegradation and COD removal of 2-chlorophenol in a granular anoxic baffled reactor.
abstract: The present work was designed to developed a granular anoxic baffled reactor (AnBR) and to investigate its performance in the treatment of 2-chlorophenol (2-CP). The acclimation and enrichment of microorganisms in activated sludge to degrade 2-CP was effectively accomplished. Then the influence of inlet 2-CP, hydraulic retention time (HRT), salinity, and type of electron acceptor (nitrate or organic compound) on the performance of AnBR in biodegradation of 2-CP was investigated. The increase of inlet 2-CP from 50 to 500mg/L at a fixed HRT of 24h did not adversely affected the AnBR where over 99% of inlet 2-CP was biodegraded. Decreasing the HRT stepwise from 24 to 4h at an inlet 2-CP of 200mg/L did not inhibit the rate of biodegradation (>99%). The increase of over 20g/L salinity in the feed stream strongly inhibited the rate of 2-CP biodegradation in the AnBR, whereas the bioreactor could efficiently tolerate concentrations below 20g/L NaCl. Moreover, the rate of 2-CP biodegradation under anoxic denitrifying metabolic conditions (presence of nitrate) was much greater than that under anaerobic metabolic conditions (absence of nitrate). Accordingly, the AnBR process is a feasible, simple, low-cost, and thus appropriate process for efficiently biodegrading toxic chlorinated organic compounds.
authors.affiliation: Department of Environmental Health Engineering, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran. Electronic address: moussavi@modares.ac.ir.
authors.forename: Gholamreza
authors.initials: G
authors.lastname: Moussavi
authors.affiliation: Department of Environmental Health Engineering, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
authors.forename: Samaneh
authors.initials: S
authors.lastname: Ghodrati
authors.affiliation: Department of Environmental Health Engineering, Faculty of Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Anoshiravan
authors.initials: A
authors.lastname: Mohseni-Bandpei
mesh_terms: D001673:Biodegradation, Environmental; D018533:Biomass; D019149:Bioreactors; D002733:Chlorophenols / Q000737:chemistry*; D012722:Sewage; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification
chemical_list: D002733:Chlorophenols; D012722:Sewage; D014874:Water Pollutants, Chemical; C030683:2-chlorophenol
keywords: Anoxic metabolism; Baffled reactor; Biodegradation; Chlorophenols; Granular biomass