Iron oxidation in a ceramic membrane bioreactor using acidophilic bacteria isolated from an acid mine drainage


Demir E. K., Nural Yaman B., Aytar Çelik P., Şahinkaya E.

JOURNAL OF WATER PROCESS ENGINEERING, vol.38, pp.101610, 2020 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 38
  • Publication Date: 2020
  • Doi Number: 10.1016/j.jwpe.2020.101610
  • Journal Name: JOURNAL OF WATER PROCESS ENGINEERING
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.101610
  • Keywords: Ceramic membrane bioreactor, Membrane bioreactor, Acidophilic iron oxidation, Acid mine drainage
  • Eskisehir Osmangazi University Affiliated: Yes

Abstract

This study aims at investigating the iron oxidation and filtration performances of a ceramic membrane bioreactor (CMBR) inoculated with a mixed culture of iron-oxidizing acidophilic bacteria isolated from a real acid mine drainage (AMD). The CMBR was fed with a synthetic solution containing 1400 mg/L Fe2+ at pH 1.5-2.5. High iron oxidation performances (around 97%) at HRT range of 48-12 h were observed. Further decreasing HRT to 6 h led to significant decrease in the Fe2+ oxidation performances. CMBR was operated at varying fluxes. Significant fouling was not observed provided that flux was 5 LMH or lower. The mixed culture was composed of Acidiphilium cryptum and Alicyclobacillus cycloheptanicus. In addition to continuous flow experiments in CMBR, Fe2+ oxidation experiments were conducted under batch conditions. Oxidation kinetics well fitted Monod equation with a specific maximum iron oxidation rate and half-saturation constant of around 3.35 mg-Fe2+/(gVSS.min) and 549 mg/L, respectively.