Integrated iron(II) oxidation and limestone neutralisation of acid mine water

Volumetric iron(II) oxidation rates exceeding 100 g/(l.d) were achieved by dosing powdered limestone to a bio-reactor treating artificial acid mine wa ter. Neutralisation and partial sulphate removal were achieved as well. The rate is highly dependent on the surface area exposed to the liquid (RSA) a nd the OH-, oxygen, CaCO3, suspended solids and iron(II) concentrations, an d less dependent on specific surface area (SSA) and pressure in the pH rang e 5 to 6, The chemical oxidation rate (pH greater than 6) is dependent on t he OH-, oxygen, and iron(II) concentrations and the reactor surface area (R SA). (C) 1999 Published by Elsevier Science Ltd on behalf of the IAWQ. All rights reserved.