The Research Of Removal Iron From Magnesite Ore

Magnesite, as a very important non-metallic mineral resources, is one of the superiority mineral resources in China, and the output and export of its corresponding products ranks first in the world. The product of magnesite is usually used for metallurgy, building materials, chemical industry, light industry, farming and magnesium refining due to its higher fire resistance, cohesiveness and other excellent physicochemical properties.The main application of magnesite is used for refractory, and the iron in it will do harm to performance quality of its product, so there is a rigorous criterion of magnesite’s impurities if it will be used for refractory material. Therefore, there is great significance of the investigation on iron removal and purification of magnesite ore. For the reason that silica is an important harmful impurity in magnesite ore, silica removal must be conducted during the iron removal process to meet the quality standards of the concentrate.This study starts from pure minerals of magnesite and limonite, the flotability difference of two minerals was investigated under the collector system of KD(self-developed cationic collector by University of Science and Technology Liaoning)and sodium oleate respectively, during which the appropriate separation p H range and adjusting agent and were chosen, afterwards, artificial mixed mineral flotation experiments were carried out. The results of pure mineral experiments showed that, when the p H value was 11.5, KD and sodium oleate were used as collector, only sodium silicate can maintain larger flotability difference between the two minerals; when the p H value was 9.5, the pure mineral experiments under collector sodium oleate showed that CMC can effectively enlarge the flotability difference between the two minerals, however, the artificial mixed mineral experiments showed a different result. And then, based on the results of pure mineral experiments, flotation tests for the purification of magnesite ore was carried out. The results showed that, under the system of KD, when the grinding fineness is- 0.074 mm 72.8%, the dosage of reagents were HCl 3000 g/t, sodium hexametaphosphate 150g/t, KD 75 g/t, concentrate of Mg O(IL = 0) 97.67%, 2Si O 0.18%, 32 OFe 0.42%, yield 80.55% can be obtained from raw ore of Mg O 94.59%, 2Si O 1.39%, 32 OFe 0.51% through the coarse fine reverse flotation process; when direct flotation process under KD system was added after the above process, and the dosage of reagents in direct flotation process were sodium silicate 1500g/t, KD 500g/t, concentrate of Mg O 98.28%, 2Si O 0.09%, 32 OFe 0.38%, yield 65.61% can be obtained; when direct flotation process under sodium oleate system was added after the above reverse flotation process, and the dosage of reagents in direct flotation process were sodium silicate 1500g/t, sodium oleate 350g/t, concentrate of Mg O 97.92%, 2Si O 0.18%, 32 OFe 0.38%, yield 74.98% can be obtained.