Low grade dumped limestone sample having high silica of 8.1%, 36.8% CaO, and 3% Al2O3 has been studied with the aim to reduce the silica level to below 3% for its utilization in iron making. Beneficiation study of the...Low grade dumped limestone sample having high silica of 8.1%, 36.8% CaO, and 3% Al2O3 has been studied with the aim to reduce the silica level to below 3% for its utilization in iron making. Beneficiation study of the sample was initiated with desliming of the feed sample of -100 μm to remove the siliceous ultrafine particles and to improve the feed quality. Flotation study was carried out by column flotation technique varying the collector dosage, superficial air flow velocity and froth depth to assess their effect on silica reduction and CaO recovery. It was observed that increased collector dosage and superficial air velocity increases the recovery of CaO, and increase in the froth depth reduces the mass flow and silica content in the concentrate. The best result was found at 1.25 cm/sec superficial air velocity, 25 cm froth depth, 1.25 kgpt collector dosage and concentrate assayed 47.3% CaO, 2.8% silica with 72% CaO recovery.展开更多
A large volume of overburden and mine wastes is generated during the extraction and beneficiation of the low grade ores. The waste low grade manganiferous iron ore fine from southern part of India was studied for reco...A large volume of overburden and mine wastes is generated during the extraction and beneficiation of the low grade ores. The waste low grade manganiferous iron ore fine from southern part of India was studied for recovery of iron values. The chemical assay of the sample is 52.36% Fe, 4.75% Mn, 8.5% SiO2 and 2.82% Al2O3. The characterization study of the sample indicates the presence of microplaty hematite, goethite, pyrolusite, cryptomelane with minor amount of quartz and kaolinite. The beneficiation study of the sample does not respond to the conventional route of desliming the ground feed followed by gravity separation and magnetic separation. Therefore, an alternative technique of reduction roasting using a producer gas was attempted at different conditions. The characterization of roasted product reveals the phase transformation to magnetite and microplaty magnetite. The low intensity magnetic separation conducted with the roasted products generated at optimal condition shows that 70% concentrate having 64.5% Fe and 1.87% Mn could be produced. The high manganese in the concentrate works as an additive for making pellet with enhancement in pellet strength and drop in reducibility. Utilization of mines waste has significant impact on mineral resources and environmental hazard.展开更多
文摘Low grade dumped limestone sample having high silica of 8.1%, 36.8% CaO, and 3% Al2O3 has been studied with the aim to reduce the silica level to below 3% for its utilization in iron making. Beneficiation study of the sample was initiated with desliming of the feed sample of -100 μm to remove the siliceous ultrafine particles and to improve the feed quality. Flotation study was carried out by column flotation technique varying the collector dosage, superficial air flow velocity and froth depth to assess their effect on silica reduction and CaO recovery. It was observed that increased collector dosage and superficial air velocity increases the recovery of CaO, and increase in the froth depth reduces the mass flow and silica content in the concentrate. The best result was found at 1.25 cm/sec superficial air velocity, 25 cm froth depth, 1.25 kgpt collector dosage and concentrate assayed 47.3% CaO, 2.8% silica with 72% CaO recovery.
文摘A large volume of overburden and mine wastes is generated during the extraction and beneficiation of the low grade ores. The waste low grade manganiferous iron ore fine from southern part of India was studied for recovery of iron values. The chemical assay of the sample is 52.36% Fe, 4.75% Mn, 8.5% SiO2 and 2.82% Al2O3. The characterization study of the sample indicates the presence of microplaty hematite, goethite, pyrolusite, cryptomelane with minor amount of quartz and kaolinite. The beneficiation study of the sample does not respond to the conventional route of desliming the ground feed followed by gravity separation and magnetic separation. Therefore, an alternative technique of reduction roasting using a producer gas was attempted at different conditions. The characterization of roasted product reveals the phase transformation to magnetite and microplaty magnetite. The low intensity magnetic separation conducted with the roasted products generated at optimal condition shows that 70% concentrate having 64.5% Fe and 1.87% Mn could be produced. The high manganese in the concentrate works as an additive for making pellet with enhancement in pellet strength and drop in reducibility. Utilization of mines waste has significant impact on mineral resources and environmental hazard.
