Biological oxidation of ferrous ions under acidic conditions using rotating biological contactor. Issue 4 (1st July 2004)

• Record Type: Journal Article
• Authors: Kapoor, A; Dinardo, O; Kuiper, A
• Is Part Of: Journal of environmental engineering and science. Volume 3:Issue 4(2004)
• Page Start: 311
• Page End: 318
• Publication Date: 2004-07-01
• Subjects: environment; Environmental engineering -- Periodicals; Sanitary engineering -- Periodicals; Environmental engineering -- Canada -- Periodicals; Environnement, Technique de l' -- Périodiques; Technique sanitaire -- Périodiques; Environnement, Technique de l' -- Canada -- Périodiques; Environmental engineering; Sanitary engineering; Canada; Electronic journals; Computer network resources; Periodicals; 628.05
• DOI: 10.1139/s04-021
• Languages: English
• ISSNs: 1496-2551

Abstract

Abstract : Oxidation of ferrous (Fe 2+ ) ion to ferric (Fe 3+ ) ion under acidic conditions can be achieved by iron oxidizing bacteria. In this research study, oxidation of Fe 2+ ions by iron oxidizing bacteria was studied using a bench-scale rotating biological contactor (RBC). Experiments were conducted to investigate the effects of parameters such as hydraulic loading rate (HLR), temperature and Fe 2+ concentration at pH 2.0 on Fe 2+ oxidation. Oxidation of Fe 2+ was observed to decrease with temperature (in the range of 5 to 23 °C). The Fe 2+ oxidation rates of 35.3 g Fe 2+ /(m 2 ·d) and 52.6 g Fe 2+ /(m 2 ·d) were observed at 5 °C and 21 °C, respectively, at HLR of 0.014 m 3 /(m 2 ·d). The Fe 2+ oxidation rates increased with increase in HLR from 0.014 m 3 /(m 2 ·d) to 0.055 m 3 /(m 2 ·d) for a Fe 2+ concentration of approximately 3200 mg/L in the RBC feed. The maximum Fe 2+ oxidation rate observed in this study was 165 g Fe 2+ /(m 2 ·d). Iron solids were deposited on the RBC disks and were identified as jarosite. The RBC was able to achieve 50% Fe 2+ oxidation efficiency after 24 h of a process upset. Key words : rotating biological contactor, ferrous, ferric, oxidation, acidic mine drainage, hydraulic retention time, hydraulic loading rate.