The progress of ilmenite flotation research The theoretical content of TiO2 of ilmenite (FeTiO3) is 52.63%, the main mineral for extracting titanium and titanium dioxide. The ilmenite beneficiation process depends on deposit type, ore properties, and mineral composition. Since the properties of primary titanium ore are relatively similar, and the target minerals are relatively simple, the beneficiation method and the beneficiation process adopted have commonalities.
The industrially developed primary ilmenite is a composite deposit containing iron and titanium. The beneficiation process is divided into two parts: iron and titanium. The raw material of the titanium dressing plant is the tailings of iron dressing. Ilmenite separation methods include gravity separation, magnetic separation, electrical separation, and flotation separation. The industrial process for selecting titanium is as follows:
Three types of ilmenite beneficiation
The beneficiation process is generally divided into the following types according to different types of ilmenite minerals:
1. Ilmenite-magnetite type beneficiation: Ilmenite in the ore often appears as an independent inclusion in the magnetite and non-metallic minerals. The principle of dealing with this type of ores is to throw the tails as coarsely as possible and then grind and magnetically separate the ilmenite concentrates.
2. Hematite-ilmenite type beneficiation: usually hematite and ilmenite in this type of ore are fine-grained and closely coexisted. The beneficiation can only select the ilmenite mixed concentrate and then use fire smelting to obtain pig iron and high titanium slag.
3. For the beneficiation of perovskite-titanomagnetite type, generally wet weak magnetic separation is used to select titanomagnetite. Then, the calcite is flotated with a fatty acid collector, and the ilmenite is flotated after the middle ore is removed.
The beneficiation process of ilmenite depends on the properties of the material. Since the specific gravity of titanium minerals is more significant than that of non-metallic gangue minerals, gravity separation can be used for pretreatment, roughing, and tailing. In contrast, the magnetic separation method is widely used in iron removal operations to improve the concentrate grade of ilmenite. Enriching ilmenite with a small proportion of gangue minerals is also possible. Electro-separation is mainly used for purification operations when the titanium concentrate selected by other processes contains various non-conductive minerals. Flotation is more suitable for beneficiation of primary ilmenite fine-grained ore.
一、Single flotation or magnetic separation process
For the ilmenite ore with fine embedded particle size, the ilmenite concentrate can be obtained directly by flotation method after grinding and iron separation, or firstly use a wet strong magnetic separator as roughing equipment, and then the magnetic separation concentrate can be used to recover titanium by flotation method. Single flotation or magnetic separation. The flotation process is relatively simple, and the operation and management are convenient, but using flotation reagents will increase the beneficiation cost.
（一）Flotation process
The flotation method is an efficient method for recovering fine-grained ilmenite. Flotation is used to separate primary titanium-bearing ores, especially for separating fine-grained titanium-bearing ores, and sometimes for the beneficiation of coarse concentrates. Flotation is an effective method for recovering fine-grained ilmenite.
Before ilmenite flotation, generally, sulfide minerals are sorted by flotation method, and then ilmenite flotation is carried out. Sulfide flotation adopts a conventional flotation reagent system, that is, xanthate is used as a collector, pine oil is used as a foaming agent, sulfuric acid is used as a pH adjuster, and some plants also use copper sulfate as an activator for sulfide flotation. The flotation research on ilmenite is generally the research on flotation reagents.
The commonly used collectors for ilmenite are primarily fatty acids and abroad are mostly oleic acid and its salts, such as tar oil soap or a mixture of collectors and kerosene. Commonly used collectors are heavy acid collectors, arsenic-containing collectors, hydroxamic acid collectors, etc. The commonly used activators in ilmenite flotation are mainly lead nitrate, pH adjusters are generally H2S04, and inhibitors are mainly water glass, oxalic acid, sodium hexametaphosphate, carboxymethyl cellulose (CMC), etc.
The single flotation method is a more effective beneficiation method for separating fine-grained embedded titanium vein ore. The single flotation process is simple and easy to operate and manage. However, due to the increased cost of chemical consumption and the environmental protection problems caused by tailings discharge, it is currently widely used in industry.
（二）Magnetic separation process
There are many kinds of titanium minerals. It has been found that there are more than 140 kinds of titanium minerals with a TiO2 content of more than 1%, but only a few minerals have utility value at this stage. Primarily ilmenite and rutile, followed by perovskite, anatase, ilmenite, brookite, and perovskite. Ilmenite accounts for about 85--95% and is the main source of titanium and titanium products. 41.4% of ilmenite exists in ore deposits, and 58.4% in vanadium-titanium-magnetite-titanium-magnetite. Ilmenite: In a hexagonal crystal system, the crystal form is a thick plate, generally brown, with a metallic luster, medium magnetic, and good conductor. Due to the close symbiosis of ilmenite with magnetite and hematite, the titanium content is lower than the theoretical value; in addition, due to partial oxidation, ilmenite can be altered to increase the titanium content, forming white titanium TiO2·nH2O. The theoretical grade is 52.63%, the Mohs hardness is 5-6, and the specific gravity is 4.7-4.78. The magnetic recombination process generally carries out the beneficiation of ilmenite. This combined beneficiation process has the advantages of large processing capacity, simple operation, low equipment investment, and good beneficiation effect.
2. Combined process
(1) Gravity separation-electric separation combined process
The gravity and roughing stage aim to discard low-density gangue and obtain coarse concentrate for power supply selection. The equipment used in electric separation is a roller electric separator, whose purpose is to enrich the gravity-separated rough concentrate further so that the product reaches the final concentrate standard. For sulfur-containing ores, flotation is usually used as an auxiliary process to remove sulfide ores between the coarse and fine concentration processes. The gravity separation-gravity separation method has attracted much attention because of its low production cost and low environmental pollution. Shaking tables are widely used in ilmenite beneficiation, especially in some small mines that use shaking tables to obtain qualified concentrates. Electric separation has been widely used as the final check operation in the production of titanium concentrate.
(2) Gravity separation-magnetic separation-flotation combined process
First, the selected materials are classified. The coarse particles are roughly separated by gravity and magnetic separation, and the fine particles are flotated to obtain titanium concentrate. The characteristic of the gravity separation-magnetic separation-flotation process is that the raw ore entering the titanium separation is first classified, the coarse-grained grade is roughly separated by gravity separation, the magnetic separation is used for fine selection, and the fine-grained grade is flotation. Gravity separation uses a shaker, and magnetic separation uses a dry magnetic separator. The flotation feed particle size is generally -0.074 mm, and the flotation machines used include sulfuric acid, sodium fluoride, oleic acid, diesel pine oil, etc. Magnetic separation - Magnetic separation has weak magnetic separation and strong magnetic separation. The function of weak magnetic separation is to separate the titanium magnetite remaining in the magnetic separation tailings to facilitate the smooth progress of strong magnetic separation. Strong magnetic separation aims to discharge qualified tailings, improve the selection grade of titanium flotation, and reduce the amount of titanium flotation ore. High-gradient magnetic separation can effectively recover the fine-grained ilmenite in the ore and throw away part of the fine mud, thereby roughing and discarding the raw ore. The ore is processed using a strong magnetic pre-selection process to improve its grade, laying the foundation for subsequent flotation to obtain the final titanium concentrate.
(3) Coarse particle gravity separation, electric separation-fine particle magnetic separation-flotation combined process
The selected materials are mainly divided into coarse and fine parts. The coarse particles are processed by gravity, rough, and electric selection. The fine particles are roughly separated by magnetic separation, and then the fine-grained titanium concentrate is obtained by flotation.
The beneficiation process that separates ilmenite from the mineral plays a vital role in the mining industry and helps extract valuable resources. Ilmenite can be effectively separated and purified mainly through gravity separation, magnetic separation, flotation, and other methods. A combination of physical and chemical processes can effectively concentrate and purify ilmenite, thereby improving the economics of mining operations. These processes are widely used in industry to meet the growing demand for titanium dioxide. JXSC aims to further enhance these beneficiation plant effects with greater precision and sustainability, benefiting the mining industry and the environment.