Upgrading of chromite concentrate by high intensity dry magnetic separation

The Presidency Turkish National Assembly;Ministry of Energy and Natural Resources;Municipality of Istanbul;Setat Mining Co.;Tuprag Mining Co.23rd International Mineral Processing Congress, IMPC 2006 --3 September 2006 through 8 September 2006 -- Istanbul --Turkey is one of the leading chromite producers and has a large share in the world's chromite ores distribution. Chromium ore is treated mainly by shaking tables with a capacity of 30,000 tonnes each year at the processing plant of Mikromaden AS, Aladag, Adana. Production capacity is about 12,000 tonnes per year of chromium concentrate with 46-48% Cr2O3. In this study, a pilot plant scale high intensity dry drum magnetic separator was applied to upgrade and increase the Cr/Fe ratio of the chromite concentrate produced by gravity concentration. The test parameters were as follows: feed rate, magnetic strength, drums speed and particle size. After magnetic separation tests, a product assaying 49.14% Cr2O3 with 3.29 of Cr/Fe ratio was obtained under optimum conditions as follows: 400 kg/h of feed rate; 3800-8200 Gauss of magnetic strength; 200 rpm of roll speed using dry magnetic separator