Transactions of Nonferrous Metals Society of China
JOURNAL OF RAILWAY SCIENCE AND ENGINEERING
|Vol. 18 No. 6 December 2008|
（Boliden Mineral AB, SE-936 81 Boliden, SWEDEN）
Abstract:A leaching process for base metals recovery often generates considerable amounts of impurities such as iron and arsenic into the solution. It is a challenge to separate the non-valuable metals into manageable and stable waste products for final disposal, without loosing the valuable constituents. Boliden Mineral AB has patented a two-stage precipitation process that gives a very clean iron-arsenic precipitate by a minimum of coprecipitation of base metals. The obtained product shows to have good sedimentation and filtration properties, which makes it easy to recover the iron-arsenic depleted solution by filtration and washing of the precipitate. Continuos bench scale tests have been done, showing the excellent results achieved by the two-stage precipitation process.
Key words: leaching; bioleaching; precipitation; iron removal