BIOLOGICAL OXIDATION OF FE2+ IN WASTE WATER

摘要

1527766 Bacterial oxidation of Fe2+ in waste water DOWA MINING CO Ltd 17 Nov 1975 [30 April 1975] 47224/75 Heading C1C A process for the oxidation with iron bacteria of the Fe2+ contained in mine, factory and other aqueous effluents at a pH so low as to provide little precipitation of basic salts, is characterized by comprising the following steps: passing the stream of waste water to be treated to an oxidation and culture zone which includes suspended beds of acid-resistant, porous and particulate material for the iron bacteria; oxidizing the Fe2+ by agitating and blowing air into the waste water with particles suspended therein to culture the iron bacteria which inhabit the particles and utilize the Fe2+ in the waste water as the energy source and at the same time to lower the Fe2+ content of the waste water; transferring the treated suspension of the iron bacteria-bearing particles from the oxidation and culture zone to a sedimentation zone; recovering the Fe3+ containing oxidized waste water in the sedimentation zone by separating the particles from the treated suspension; and returning the separated particles which the iron bacteria inhabit to the oxidation and culture zone. The effluent may have a pH of 2À0 or lower. Diatomaceous earth is a suitable porous material for supporting the bacteria. Acidic mine effluent is especially suitable for treatment in this way. The iron bacteria live in water and obtain the energy for maintaining their life by oxidizing Fe2+ to Fe3+. They are often found in mine water.