Selenium recovery from kiln powder of cement manufacturing by chemical leaching and bioreduction

Water Sci Technol. 2015;72(8):1294-300. doi: 10.2166/wst.2015.339.

Abstract

A novel process by using chemical leaching followed by bacterial reductive precipitation was proposed for selenium recovery from kiln powder as a byproduct of cement manufacturing. The kiln powder at a slurry concentration of 10 w/v% with 0.25 M Na2CO3 at 28°C produced wastewater containing about 30 mg-Se/L selenium. The wastewater was diluted four-fold and adjusted to pH 8.0 as preconditioning for bioreduction. A bacterial strain Pseudomonas stutzeri NT-I, capable of reducing selenate and selenite into insoluble elemental selenium, could recover about 90% selenium from the preconditioned wastewater containing selenium of 5 mg-Se/L when supplemented with lactate or glycerol. The selenium concentrations in the treated wastewater were low around the regulated effluent concentration of 0.1 mg-Se/L in Japan.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chemical Precipitation
  • Industrial Waste
  • Japan
  • Oxidation-Reduction
  • Pseudomonas stutzeri / metabolism*
  • Selenic Acid / metabolism*
  • Selenium / isolation & purification*
  • Selenium / metabolism
  • Selenium Compounds
  • Wastewater

Substances

  • Industrial Waste
  • Selenium Compounds
  • Waste Water
  • Selenium
  • Selenic Acid