International Journal of Applied Environmental Sciences

  • Year: 2009
  • Volume: 4
  • Issue: 3

The study of oxygen diffusion process in metallic waste dump: Analytical and Numerical Modeling

  • Author:
  • Ahmad Aryafar, Faramarz Doulati Ardejani
  • Total Page Count: 8
  • DOI:
  • Page Number: 287 to 294

Faculty of Mining Engineering, Oil and Geophysics, Shahrood University of Technology, Shahrood, Iran, P.O.Box: 36155-316.

Abstract

Weathering of pyrite–containing rocks causes the well-known problem of acid rock drainage. Depending on the rate of pyrite oxidation, availability of water and oxidants and buffering capacity of surrounding rocks and sediments, the pH of the drainage is often very low. When the pyrite or other sulphide minerals are exposed to the atmosphere and water, the acid mine drainage was generated. Oxygen can be transported into the waste deposit by three mechanisms: (1) advective transport with water, (2) free ore forced air convection and (3) diffusion in the gaseous and aqueous phases through pores in waste material. Pyrite oxidation and acid mine generation are often controlled by the oxygen diffusion process. So, this research attempts to investigate the variation of oxygen concentration in the pyritic waste dump using analytical and numerical model incorporating PHOENICS computational fluid dynamics software. The obtained results can be used to control and reduce the environmental impacts.

Keywords

Numerical modeling, Analytical model, Oxygen diffusion, Waste dump, Sulphide mineral, PHOENICS software