Common ilmenite beneficiation methods - ilmenite recovery methods. In nature, ilmenite resources can be divided into two categories based on actual conditions: primary ilmenite and sandy ilmenite. Among them, primary ilmenite is often associated with titanium magnetite and vanadium titanium magnetite, characterized by large and concentrated reserves, suitable for large-scale mining, but with high gangue content, low recovery rate, and poor selectivity. Sandy ilmenite belongs to secondary ores, characterized by loose structure and good washability, but with low grade of the original ore and easy mudification of the ore. From this, it can be seen that different characteristics of ilmenite ore also put forward different requirements for ilmenite beneficiation methods. At present, the common beneficiation methods for ilmenite include gravity separation, magnetic separation, electrostatic separation, flotation, and combined methods.
1、 Re selection method for recovering ilmenite
The reselection method is suitable for coarse-grained and fine-grained aggregate impregnated ilmenite. After coarse and medium crushing, a large amount of gangue and desliming can be discarded through reselection equipment such as spiral chutes and shaking tables.
2、 Recovery of ilmenite by magnetic separation method
Titanium iron ore belongs to weakly magnetic minerals, with a higher specific magnetic ratio and density than vein minerals. For minerals of the same particle size, it has much larger volumetric magnetization than vein minerals. In this way, when magnetic separation is carried out under a certain field strength (electric field strength and direction), the vein minerals and some fine-grained iron silicate minerals in ilmenite are easily thrown into the tailings. Through strong magnetic separation, ilmenite and vein minerals can be effectively separated, achieving the goal of enriching titanium metal and processing difficult to enrich ilmenite. It is commonly used in processes such as selection and tailings throwing.
3、 Recovery of ilmenite by flotation method
Flotation, as a highly accurate and effective sorting method, is mainly used in the selection process of primary titanium ore or fine-grained titanium iron ore, including conventional flotation, flocculation flotation, agglomeration flotation, etc.
1. Conventional flotation of ilmenite
Common collectors include oleic acid and its soaps, oxidized paraffin soap, tar oil, and new collectors such as TAO, R-2, H1717, ZY, RST, TOB, etc. Among them, oleic acid and its soaps are commonly used ilmenite collectors with mature and reliable technology. Their collection performance can be improved by heating, increasing oxygen content, or adding emulsifiers. However, the disadvantages are high drug consumption and poor selectivity. Oxidized paraffin soap is a product obtained by the oxidation saponification of paraffin wax. It has a wide source and low cost, and can replace oleic acid. It needs to be emulsified at room temperature to improve its collection effect. The concentrate grade is low and unstable.
2. Ilmenite flocculation flotation
Flocculation flotation mainly includes selective flocculation method and hydrophobic flocculation method. Selective flocculation is a method of aggregating and flocculation a mineral from a dispersed system of two or more minerals. Hydrophobic flocculation refers to the phenomenon of hydrophobic particles suspended in water attracting each other to form clusters due to hydrophobic interactions. Hydrophobic clusters are achieved by adding collectors and neutral oil under high-speed stirring. The flocculation flotation of ilmenite is a flotation technology that selectively flocculates fine particles of ilmenite by adding coagulants such as polyacrylamide to form flocs.
3. Agglomeration flotation of ilmenite
Agglomeration flotation of ilmenite is a technology that uses a collector to adsorb onto the surface of ilmenite to make it hydrophobic, and uses the capillary attraction of a liquid bridge to enable the aggregation of mineral particles to float and separate as a whole. Intense stirring is crucial in the agglomeration flotation process, as it can provide more energy to the particles, overcome the energy barriers between them, make the surface of the particles hydrophobic, and trigger coagulation into clusters, ultimately achieving the goal of ilmenite beneficiation.
4、 Electric selection method for recovering ilmenite
The electric selection method is mainly used to process the coarse concentrate containing non-conductive impurities such as titanium pyroxene produced by re-election and magnetic separation. It is widely used in the selection process. The electric selection method has requirements for the particle size of ilmenite, with a lower limit of 0.04mm. Pre treatment such as heating and radiation irradiation is required before electric selection to ensure the normal operation of the electric selection process, avoid unnecessary situations, and improve the efficiency of mineral processing technology.
5、 Joint method for recycling ilmenite
The use of combined methods often yields better recovery results than single methods, with main methods including magnetic separation flotation, gravity separation flotation, magnetic separation gravity separation, gravity separation magnetic separation flotation electric separation, etc.
Among them, for the magnetic separation flotation combined method, the recovery method of fine particle size of ilmenite has always been its focus and difficulty. Flotation can basically achieve the recovery of -0.02mm particle size ilmenite, but a large amount of quartz and other gangue will affect the flotation indicators. Therefore, strong magnetic pre tailings can be used to improve the flotation environment. The re-election flotation combined method mainly uses re-election equipment such as spiral chutes and shaking tables for rough selection and fine selection, to obtain qualified coarse concentrate. After flotation desulfurization, titanium concentrate and sulfur concentrate can be obtained, achieving comprehensive utilization of mineral resources. For the magnetic separation reselection combined method, although sand titanium ore can be enriched through simple reselection or magnetic separation, the magnetic separation reselection combined method can obtain better indicators and reduce costs. For ores containing mainly ilmenite and plagioclase in the original ore, as well as sulfide minerals, the combined method of gravity separation magnetic separation flotation electric selection can remove plagioclase by gravity separation, desulfurize by flotation, and remove ilmenite by electric selection.
In summary, the selection of beneficiation methods for ilmenite primarily depends on the properties of the material. Due to the higher specific gravity of titanium minerals compared to non-metallic gangue minerals, it can be used for pretreatment through re-election or for rough selection and tailings disposal. It can also be used for enrichment operations on ilmenite with lower specific gravity of gangue minerals. The magnetic separation method is widely used in iron removal operations to improve the concentrate grade of ilmenite. The electric selection method is commonly used for purification operations when titanium concentrates selected by other processes contain various non-conductive minerals. Flotation is more suitable for the beneficiation of fine-grained primary ilmenite ore. The joint beneficiation method can fully utilize the advantages of various beneficiation methods based on the ore properties of ilmenite, thereby ensuring ideal beneficiation indicators and economic benefits.