Recovering limonite from Australia iron ores by flocculation-high intensity magnetic separation

Abstract

Successful recovery of limonite from iron fines was achieved by using flocculation-high intensity magnetic separation (FIMS) and adding hydrolyzed and causticized flocculants according to the characteristic of iron fines. The separation results of the three iron samples are as follows: iron grade 66.77%–67.98% and the recovery of iron 69.26%–70.70% by the FIMS process with flocculants. The comparative results show that under the same separation conditions the FIMS process can effectively increase the recovery of iron by 10.97%–15.73%. The flowsheet results confirm the reliability of the process in a SHP high intensity magnetic separator. The concentrate product can be used as raw materials for direct reduction iron-smelting. The hydrolyzed and causticized flocculants can selectively flocculate fine feebly-magnetic iron mineral particles to increase their apparent separation sizes. The larger the separation size, the stronger the magnetic force. By comparing the separation results of the three samples it is found that among the three samples the higher the limonite content, the better the separation result. This means that the separation result relates closely to the flocculation process and the adding pattern of the flocculant.

Keywords

Australia iron ores / flocculation / high intensity magnetic separation / limonite

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