Characterisation and Pre-concentration of Chromite Values from Plant Tailings Using Floatex Density Separator
- 1 R&D Department, TATA Steel Limited, Jamshedpur, India
- 2 R&D Department, TATA Steel Limited, Jamshedpur, India
- 3 Mineralogy Dept., IMMT, Bhubaneswar, India
Abstract
Classification is a method of separation of fines from coarse particles and also lighter particles from heavier particles. The conventional classifiers, such as, hydrocyclone or mechanical classifiers, decreases the efficiency of the grinding and concentration circuits due to their imperfect separation. In the process of improving the efficiency of classification, a device that has been gaining popularity in recent years is the teeter-bed or hindered-bed separator such as Floatex density separator. Generally for processing chromite ores, different types of gravity methods are employed after crushing, grinding followed by classification. The Tata Steel Chrome Ore Beneficiation (COB) plant is generating 50 tph of tailings assaying 17% Cr 2 O 3 . A critical review on practice of the plant operating personnel is concerned in the grade-recovery characteristics of unit operations. But separation insight and influence of different operating and process parameters are essential to understand and control the process. The objective of the present investigation was to study the effect of the important operating variables on floatex density separator and preconcentration of COB plant tailings for the further beneficiation process and found that significant removal of iron bearing mineral such as goethite and silica is possible using FDS in a single stage operation. The maximum of 83% recovery of chromite is possible with 22 to 23% Cr 2 O 3 content and thus obtained FDS underflow is suitable for flotation circuit. A low teeter water flow rate with a high bed pressure removes iron bearing mineral like goethite efficiently in an FDS.
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