| Abstract:Being regarded as "metal vitamin", vanadium displays many excellent physical and chemical properties, and it has been ranked as strategic materials. Stone coal is a typical kind of organic shale buried in the ancient strata after a long period of geological changes. With the average content of V2O51.0%, stone coal is a unique resource of vanadium. Since our country is rich in stone coal, the technology of extraction vanadium from stone coal has an important influence on our vanadium industry.Present technology of extraction vanadium from stone coal is associated with many negative problems, such as low recovery rate, large reagent consumption, high production cost and environment pollution. In this paper, concerning a low-grade siliceous vanadium-containing stone coal, the author conducted a lot of work based on the previous research. Firstly, the author analyzed the mineralogy of vanadium in stone coal and put forward "scrub-flotation and leaching" efficient enrichment process based on a lot of theoretical analysis and experimental research. This process provides the reference for this stone coal mine and other mines with similar ore characteristics has obvious economic benefits and theoretical guiding significance. The main experiment for vanadium-containing single mineral includes:the Zeta potential and adsorption test for studying the adsorption mechanism between collector and vanadium-containing single mineral; scrubbing and sedimentation research for fine grain illite. Main research contents and innovations are as follows:(1) Mineralogy research shows that:the vanadium grade of this stone coal is very low, belongs to the low carbon stone coal; the concentration of quartz reaches75.34%; the grade of V2O5is0.68%. Vanadium is mainly distributed as isomorphism in mica mineral and adsorbed condition in ferric oxide and clay minerals such as illite. Vanadium in stone coal is unevenly distributed, mainly occurs in the grain size of0.038mm.(2) Single mineral research show that:for vanadium-containing mica and illite, the separation effect of YL1is not as good YL2. By the anionic collector, flotation behavior research of the vanadium-containing mica, illite and quartz show that SDBS works best. Using the combined collector of cationic and anionic, with total dosage of1.2×10-4mol/L, the recovery of mica is more than90%, recovery of illite is around40%and that of quartz is less than20%, which can accomplish the separation of mica, illite and quartz. Finally, the author studied the influence of unavoidable Ca2+on the flotation behavior of vanadium mineral.(3) Collector-mineral interaction studying indicates that:in distilled water, the negative zeta potential of mica, illite and quartz increase with the increase of pH, showing that the mineral surface hydroxyl degree increases with the increase of pH value. In the YL1, zeta potential of mica, illite and quartz increase toward the positive direction, while in SDBS, the zeta potential to the negative direction, this shows that the collector has adsorption behavior in the mineral surface. Adsorption behavior in YL1system and SDBS system of SDBS mica, illite and quartz surface is consistent with single mineral flotation results.(4) Scrubbing-settlement of the grained illite shows that:for the dispersion-settlement experiment of illite with-0.01mm ultra fine fraction, adoptting the method of wash-settlement, we can efficient recycle the grained illite.(5) Actual ore study shows that:in accordance with the "scrub desliming-flotation" joint enrichment process test, the grade of V2O5in ore can be enriched from0.67%to1.87%, expeling the as much as72.91%of the gangue mineral, including most of the acid consumption mineral, reducing the heat energy required by subsequent leaching and the dosage of leaching agent; overall subsequent metallurgical extraction cost was reduced. |
PDF Full Text Request