Pre-concentration Of Vanadium From High Calcium Mica-type Vanadium-bearing Stone Coal By Flotation Process

Vanadium-bearing stone coal is an unique and regnant resource in our country,the total reserve of it is abundant and it's widespread in China,extracting V2O5 from Vanadium-bearing stone coal has become an important way of obtaining vanadium resource, is of great significance. As early as in the 1960 s,the researches of leaching vanadium from stone coal have been studied,however,due to the properties of vanadium-bearing stone coal are complex,the vanadium grade and occurrence is generally low and multiple,the technology of current vanadium extraction faces the problems in terms of large ore quantity, low vanadium leaching rate, high consumption of acid and alkali auxiliary materials and serious environmental pollution,these problems restrict the development of vanadium extraction industry. In order to solve these problems, the article used high calcium mica-type vanadium-bearing stone coal from Hubei province as research object and put forward a new process for pre-concentration of vanadium from stone coal by the flotation pre-enrichment,enriched tne vanadium-bearing minerals and reduced the content of acid consumption, thereby raised the grade of V for the vanadium extraction. This research carried out mineralogical studies of vanadium-bearing stone coal and its roasting decarburization sample,and designed the principle of flotation process on the basis of mineralogical studies, then determined the floatation pre-concentration process of vanadium and its best parameters by condition experiment.The main contents and results are as follows:(1) Vanadium-bearing stone coal from Hubei province belonged to high calcium mica-type stone coal with low grade of vanadium and high content of carbon,the grade of V2O5 was 0.71%,CaO was 6.26% and the carbon content was 13.44%,vanadium mainly distributed in Muscovite as isomorphism in the state of V(?) or V(?). It was confirmed that the primary minerals were Quartz,Muscovite,Calcite and Pyrite,other minerals were Feldspar and Kaolinite. Quartz was fine-grained, lenticular or fine pulse distribution;Calcite and Pyrite were granular distribution,co-existed with Quartz and Muscovite; Muscovite was flake or strip and interacted with other minerals. After roasting,the grade of V2O5 rose from 0.71% to 0.83%,Pyrite oxidized into Hematite, the content was 11%,part Calcite decompose, content reduced from 11% to 9%,and Pyrite with Calcite generated small amounts of anhydrite in the high temperature,Kaolinite translated into Partial Kaolinite.(2) In the Vanadium-bearing stone coal from Hubei province, the vanadium-bearing mineral was Muscovite,gangue minerals were Quartz,Calcite and Feldspar et al, used QEMSCAN mineral quantitative image analyzer to statistic average particle size of roasting decarburization sample,found the average grain diameter of Muscovite was 5.41 ?m,and the average grain diameters of Quartz?Calcite?Feldspar respectively were 25.55 ?m?34.94 ?m and10.25 ?m,by the statistical analysis results,we known that the particle size between vanadium-bearing minerals and gangue minerals were different,the stone coal belonged to unequal particle disseminated ore,should choose the selective grinding of rod mill. Then according to the analysis results of Roscoelite monomer dissociation degree,the optimum grinding fineness was-0.074 mm 70~80%.(3) The circuit of “Reverse flotation of acid consumption minerals,and normal flotation of vanadium-bearing Muscovite”was established through floatation pre-concentration process. Reverse flotation selected the separation process of“Scattered desliming—Reverse flotation of Calcite”, through a floation could achieve better results;Due to the adverse effects of reagents which added in the reverse flotation process, the normal flotation used the circuit of“Scrub off reagents—Normal flotation of vanadium-bearing muscovite”, associated slime in scrub off reagents as vanadium concentrate,flotation Muscovite with the “single roughing and scavenging”process, then could get slime, calcium concentration, vanadium concentrate and tailings products, calcium concentrate and tailings consolidated as the final tailings, slime and concentrate consolidated as the final concentrate. Finally got the vanadium oncentrate with the yield was 53.82%, V2O5 grade was 1.14% and vanadium recovery was 73.66%.