Selection of test plan for vanadium-titanium magnetite

A, vanadium and titanium ore selection magnet

Vanadium-titanium magnetite can be recovered by weak magnetic separation because of its strong magnetic properties. The beneficiation of vanadium-titanium magnetite is to crush or grind the original ore to -0.074mm, which accounts for about 45%. After rough selection and rough selection, a vanadium-titanium iron concentrate can be obtained. Its TFe is above 51.5%, V ₂ O _{5 is} 0.5% to 0.6%, the iron recovery rate is about 72%, and the V ₂ O ₅ recovery rate is 80%. See Figure 1 for details.

Figure 1 1 paragraph grinding process

Since the vanadium in the titanomagnetite is homogeneous, the average content is 0.3% to 0.4%, and 80% to 90% is present in the titanomagnetite, and the titanomagnetite contains V ₂ O ₅ 10 ^{- 3} . Titanium magnetite present in the V ₂ O ₅ only 1.44% ~ 4.03% content of the ore, ilmenite containing grade of V ₂ O ₅ 10 ^{- 5} to ^10--4. Rest titanium contained in the gangue minerals pyroxene and plagioclase in.

In order to meet the requirements of Panzhihua Iron and Steel Co., Ltd. to improve the quality of vanadium-titanium concentrate, the current production process of the Panzhihua Mining Company's Midi Concentrator has been transformed from the original grinding magnetic separation process to the magnetic separation process of the stage grinding stage. The grinding size is -0.074mm65. %～70%, the iron grade of vanadium-titanium magnet concentrate is increased from 51.5% to 54%-55%. The TiO ₂ grade in the product iron concentrate has no obvious change compared with the original production process. The SiO ₂ grade is in phase with the original production process. The specific content decreased. The other elements V ₂ O ₅ , Al ₂ O ₃ , CaO, MgO, and S did not change significantly. The V ₂ O ₅ grade is 0.563% to 0.585%, as shown in Figure 2.

Figure 2 Stage grinding process

Second, vanadium-containing magnetic (red) iron ore beneficiation process

The concave mountain concentrator adopts a three-stage closed-circuit crushing system and a two-stage full-closed grinding system and a weak magnetic-strong magnetic separation process (Fig. 3). The main production indicators of the factory in 1998 are shown in Table 1.

Figure 3 Concentration process of the concave mountain plant

Table 1 Production indicators of selected plants in 1998

The produced iron concentrate has a V ₂ O ₅ of 0.3% and a low grade, which is used for smelting steel to extract vanadium. In recent years, fine mineral rate of 30.64 percent iron, about TFe64.09%, 79.82% recovery of iron, tailings TFe9.23%, ore TFe26.04%, iron ore in V ₂ O ₅ is still 0.3%.

Third, extract vanadium from vanadium-titanium magnetite concentrate

Vanadium is extracted from magmatic vanadium-titanium magnetite, and the smelting method for extracting vanadium from vanadium-titanium concentrate is either fire method or wet method. The fire method is to indirectly extract vanadium from vanadium-titanium concentrate or vanadium slag, and the wet method directly extracts vanadium from vanadium-titanium concentrate. At present, China mainly uses indirect vanadium extraction.

Vanadium extraction process by fire method. The vanadium-titanium concentrate of the ore dressing product is directly smelted into the blast furnace or electric furnace, so that most of the vanadium in the ore enters the molten iron, and then the vanadium-bearing iron water is sent into the converter for oxygen blowing, so that the vanadium is enriched in the slag and becomes vanadium slag. The vanadium slag is calcined, leached and filtered to obtain vanadium pentoxide. The biggest advantage of this method is the high recovery of vanadium, which is especially suitable for the utilization of low-grade vanadium ore. The disadvantage is that the ore is processed in a large amount, and the production scale is small, which is incompatible with the large-scale production of the steel industry.

The process of producing ferro-vanadium slag from vanadium-titanium magnetite is shown in Figure 4.

Figure 4 Process of ferro-vanadium slag from vanadium-titanium magnetite

In the past 20 years, China has accumulated a lot of experience in the vanadium-titanium magnetite extraction process and pioneered the blast furnace ironmaking-atomization vanadium extraction method. Currently, Panzhihua Iron and Steel Co., Ltd. has used this method to mass produce vanadium slag. The characteristic of the process is that the iron is slag and rectified in the intermediate tank, and atomized in the atomizer, and the atomized molten iron enters the atomization furnace to react, and the molten iron (semi-steel) after the vanadium is introduced into the semi-steel tank, so that The vanadium slag layer is formed on the surface of the semi-steel tank, and the vanadium slag is obtained by separating the semi-steel. The vanadium slag is melted, leached and filtered to obtain a vanadium pentoxide product. See Figure 5.

Figure 5 Process of atomizing blown vanadium slag by Panzhihua Iron and Steel Company

Vanadium extraction process by wet method: the vanadium-titanium concentrate is added to the mirabilite group, and after roasting and water immersion, sodium vanadate is introduced into the solution, and then sulfuric acid is added to convert it into vanadium pentoxide. The pellet after water immersion is reused. Iron making. The advantage of the vanadium extraction by wet method is that the process is short and the recovery rate of vanadium is high.

Fourth, vanadium containing steel slag

One of the main raw materials for extracting vanadium is vanadium-titanium magnetite. Vanadium is recovered from vanadium-titanium magnetite. The common method is to smelt vanadium-bearing pig iron in a blast furnace to selectively contain iron-containing pig iron. After vanadium is oxidized, it enters the slag, and a high content of vanadium-containing steel slag is obtained as a raw material for extracting vanadium.