Selection of test plan for molybdenum oxide ore dressing

Molybdenum oxide mineral that has some value only only molybdenum mine calcium, iron and molybdenum Hua Cai molybdenum lead ore.

    First, the selection of molybdenum and calcium deposits

The molybdenum-calcium ore flotation process is divided into two types: flotation and mixed flotation.

Separate flotation is a process for recovering molybdenum-calcium ore from molybdenite flotation tailings. 1950 Soviet Union И · A · Principal Strickland who first studied and gold for the first time Barr Hashemi mineral processing plant, east of La Cohen molybdenum sulfide flotation tailings recovery of molybdenum calcium deposits.

Molybdenum ore calcium collectors commonly used oleic acid (about 100g / t), while for the recovery of molybdenite, must kerosene was added (200g / t), using a foaming agent xylenol. The flotation production process includes rough selection, sweep selection, coarse concentrate addition to water glass (1300g/t), steaming (temperature treatment at 85 °C for 30-40 minutes), filtration, drug removal, and slurrying with fresh water. Four selections. The recovery of kerosene and oleic acid is weak and the selectivity is poor. Therefore, the grade and recovery rate of molybdenum-calcium ore in foam products are low, and it is impossible to produce qualified molybdenum concentrate, which can only obtain 7.5%-15% of molybdenum. Copper, 2% to 3%, 30% to 35% calcium, 3% to 8% iron, and 4% to 6% sulfur. The medium mine is also subjected to a calcination-leaching extraction process to prepare calcium molybdate (CaMoO ₄ ).

The former Soviet Union Institute of Mining Research studied the use of sodium alkyl sulfate as a dispersant for oleic acid and kerosene. The effect is shown in Figure 1 and Figure 2.

Figure 1 Effect of emulsifier (sodium alkyl sulfate) on flotation of molybdenum-calcium ore

Figure 2 Effect of dispersant on flotation of molybdenum-calcium ore

Obviously, the addition of a small amount of dispersant sodium alkyl sulfate can increase the recovery rate and floating speed of molybdenum ore.

The “separate” flotation failed to obtain qualified molybdenum concentrate, and the flotation equipment increased. To this end, the former Soviet Union Institute of Mining Research studied the process of "mixing" the collection of molybdenum sulfide and molybdenum oxide.

The "separate" flotation and "mixed" flotation kinetic curves are compared, as shown in Figures 3 and 4.

Figure 3 Flotation kinetics curve of molybdenum oxide

Figure 4 Total molybdenum flotation kinetics curve

It can be seen from the figure that the “mixing” and “separate” flotation process indicators are the same, but the flotation speed is faster and the flotation time is shortened. Obviously, molybdenum sulfide and molybdenum oxide minerals can be mixed and floated without reducing the quality of the concentrate.

The molybdenum or molybdenum-calcium ore mixed flotation was industrially tested in 1963. The test was carried out on the original sulfide ore flotation series. The ball mill was added with soda (600g/t) and kerosene (200g/t). The mixture was added with sodium oleate (100g/t) and alkyl sulfate (10g/t). Kerosene was also added to the selection and sweeping. The sodium oleate and alkyl sulfate also had foaming properties, and the amount of the foaming agent xylenol was reduced by 50%. The steaming and selection processes have not changed much. The test confirmed that the mixed flotation ratio was “separate” flotation, and the molybdenum recovery rate was increased by 5% on average.

Whether to adopt mixed flotation, first of all depends on whether a qualified mixed molybdenum concentrate can be obtained, and the molybdenum-calcium ore concentrate produced by the "separate" flotation contains 7.5% to 20% of molybdenum. According to this calculation, the molybdenum in the mixed concentrate is calculated. The calcium ore portion cannot exceed 13% to 18% of the total amount of molybdenum. That is to say, the proportion of molybdenum-calcium ore in the original ore cannot be too high, otherwise it is difficult to ensure the quality of the mixed concentrate.

The molybdenum-calcium ore in the molybdenum deposit is mainly a product of tungsten in the molybdenum-like substitution of scheelite (CaWO ₄ ), and a rare molybdenum-calcium ore containing no tungsten is rare. Molybdenum enters the tungsten mineral lattice to replace tungsten, and as the substitution amount increases, scheelite, tungsten molybdenum ore, molybdenum tungsten ore, molybdenum ore is formed. Its crystal form is the same as scheelite and molybdenum calcium; its planking performance is similar to that of scheelite and molybdenum ore. The tungsten ore containing molybdenum ore is in the flotation, the molybdenum-calcium ore and the scheelite cannot be separated, and at the same time enter the tungsten concentrate, and then the leaching-extraction process is used to separate and purify the molybdenum product.

    Second, the selection of iron molybdenum

Iron-molybdenum ore flotation is a very complicated problem.

Among the ores, iron-molybdenum is closely related to limonite and iron meteorite, and is micronized. Clay Max and molybdenum oxide on the main goethite, jarosite followed symbiosis. These minerals are brittle, easy to mud in the grinding, and the particle size of the impregnation is extremely fine. The distribution of different particle sizes of the Moorish molybdenum ore is shown in Fig. 5.

Figure 5 Solsk various grades of molybdenum content

Therefore, it is more difficult to select iron-molybdenum ore than molybdenum-calcium ore. The rich ore ratio is smaller, and only low-grade medium ore can be produced, and molybdenum products can be prepared by leaching-extraction process.

The flotation of iron-molybdenum is the use of oleic acid as a collector in the soda (Na ₂ CO ₃ ) medium. In order to recover the molybdenum sulfide, it is also necessary to add kerosene.

The Sorkutsk branch of the former Soviet Union Institute of Rare Metals proposed the process of selecting Solsk Molybdenum Oxide: 6000g/t soda, 1500g/t oleic acid, 1500g/t kerosene, 100g/t pine oil, once Rough selection, one sweep, the results are listed in Table 1.

Table 1 Solsk flotation molybdenum oxide results

The amount of oleic acid (1500g/t) and the price are very high, so г·A·Haro and A·Й Zarahani recommend the use of oxidized paraffin as an oleic acid substitute and can be applied in Solsk.

Industrial trials use soda (2200 ~ 3000g / t), oxidized paraffin soap (2000 ~ 3000g / t), kerosene (1500 ~ 2250g / t) by rough selection, sweeping, two selection processes. For the ore containing oxidized molybdenum grade ≥0.045%, a molybdenum intermediate ore with a recovery of 65%-80%, containing 0.32%-0.52% of total molybdenum and 0.3%-0.5% of oxidized molybdenum may be obtained. For the selected ore containing oxidized molybdenum grade <0.045%, a recovery of 51% to 61%, containing 0.22% to 0.28% of total molybdenum, or 0.21% to 0.27% of oxidized molybdenum may be obtained.

Because iron-molybdenum is easy to be muddy and difficult to select, the rich ore ratio of flotation is very low, and the flotation product must be processed by leaching-extraction process.

For the locally enriched iron-molybdenum ore-rich ore in the molybdenite deposit, separate mining and direct leaching-extraction may be considered. Claymax is directly leaching the production of chemicals from the oxidized molybdenum ore in the deposit. The Sandaotong molybdenum deposit in Luanchuan also has local iron-rich molybdenum production, which is yet to be researched and developed.