Beneficiation technology of ilmenite and zirconium ore

I. Titanium and zirconium resources and production

1. Titanium resources and production

The world's proven reserves of 710 million tons of titanium resources (in terms of titanium, the same below), in which titanium iron ore reserves of 5.6 billion tons of reserves of 170 million tons of rutile titanium industrial reserves of 2.7 billion tons.

2. Zirconium resources and production

The world's zirconium reserves mainly occur in the coastal sand deposits, and only a small part of them are found in residual sand ore and primary ore, and the industrial value is not large. Zirconium is the main mineral resources of zircon and baddeleyite, and they are mostly ilmenite, monazite, rutile, xenotime, cassiterite and other minerals symbiotic, was integrated sands ore deposits. Australia's zirconium resources and production ranked first, followed by the United States, South Africa and other countries.

Second, titanium zirconium concentrate quality standards

The quality of titanium lead concentrate varies with resources, and there is no international standard. Therefore, the companies or manufacturers of each producing country have their own standards according to their resource characteristics and user requirements.

Mineral beneficiation process and zirconium titanium ore deposit used will depend on the type of factors, the nature of the ore and mineral composition and the like. In view of the relatively similar nature of the titanium ore deposits, the target minerals are relatively simple, and the beneficiation methods and processes used are common; while the titanium and zirconium minerals in the titanium and zircon deposits are more monazite. The symbiosis of xenotime, cassiterite and precious metals is produced by a comprehensive sand deposit. Therefore, the beneficiation of titanium and zirconium ore is carried out from rough selection to selection into a common beneficiation process. In this section, the beneficiation of titanium and zirconium ore is divided into two parts: titanium primary ore (pulse ore) ore dressing and titanium and zircon sand ore beneficiation.

1. Beneficiation of titanium primary ore (pulse mine)

At present, the titanium primary ore (pulmonary ore) utilized in the industry is a composite iron ore containing titanium. In order to utilize the titanium resources, depending on the nature of the ore, the entire beneficiation process can be divided into three stages: pre-selection, iron selection and titanium selection. The titanium part can be divided into two stages: rough selection and selection.

(1) Pre-selection

Some titanium vein ore, when crushed to a certain degree of coarse grain state, a considerable number of gangues to achieve basic monomer dissociation, these coarse-grained monomer gangue can be discarded by pre-selection operation, to increase the selection of plants Processing capacity and the purpose of improving the selected grade. The pre-selection operation can be carried out according to the nature of the ore at the appropriate stage of the coarse, medium and fine crushing operations before the grinding operation. The pre-selected common methods are magnetic separation and re-election.

(2) Iron selection

Titanium-containing composite iron ore, the main purpose of industrial utilization at present is to obtain iron concentrate for iron making; for ore containing high vanadium , it is obtained from ferro-vanadium and vanadium-iron concentrate for iron making and vanadium extraction. The iron selection is carried out by a simple and effective magnetic separation method. After the ore is crushed (or pre-selected) and ground to achieve the optional monomer dissociation degree, the iron concentrate or vanadium iron concentrate is selected by a drum type or a belt weak magnetic field wet magnetic separator. Magnetic separation tailings are the raw materials for comprehensive recovery of titanium. Some ore iron and titanium minerals are densely embedded. It is difficult to obtain a single concentrate by a single beneficiation method. Only the tailings are discarded by re-election, and the obtained iron and titanium mixed concentrates are directly calcined and smelted to produce High-purity pig iron and titanium slag products.

(3) Titanium selection

The recovery of titanium in the titanium vein ore is carried out in a magnetic separation tailing after the iron concentrate is selected. The methods used for titanium selection include re-election, magnetic separation, electro-election and flotation. Depending on the nature of the ore, different mineral processing methods are used to form different process flows for sorting. At present, the beneficiation process used in the industry has the following types: Re-election-Electrical Separation Process Re-election-Electrical selection process is characterized by re-election and rough selection. The equipment used for re-election is mainly a spiral concentrator (including spiral slip), followed by a shaker. Re-election with a conical concentrator has been carried out to the industrial test stage, but has not yet been formally used for production. In the re-election roughing stage, the purpose is to discard the low-density gangue and obtain the coarse concentrate selected for power supply. The equipment used for electrification is a roller type electric separator, the purpose of which is to further re-select the coarse concentrate to achieve the final concentrate standard. For sulfur-bearing ores, flotation is commonly used as an auxiliary process for the removal of sulfide ore between the coarse and fine processes. Re-selection - magnetic separation - flotation process re-election - magnetic separation - flotation process is characterized by the entry of titanium into the ore, first classification, coarse-grained re-election, magnetic separation, fine-grain Use flotation. The re-election is carried out using a shaker, and the magnetic separation is carried out using a dry magnetic separator. The flotation feed size is generally -0.074 mm, and the flotation agents used are sulfuric acid, sodium fluoride, oleic acid, diesel oil and pine oil. Single-flotation process Single-flotation method is a more effective beneficiation method for selecting fine-grained titanium veins. The single flotation process is simple, and the operation and management are convenient. However, since the consumption of chemicals will increase the cost and the environmental protection problems caused by tailings discharge, the current industrial application is not widespread. The flotation agents used in the flotation of titanium include sulfuric acid, tart oil, diesel oil and emulsifier Etoxolp-19. In order to improve the flotation effect, the high concentration and long-term stirring of the ore dressing and flotation agent before flotation has a certain effect.

2. Beneficiation of titanium zirconium ore

The main deposit type of titanium zirconium ore is coastal sand mine, followed by inland sand mine. Titanium zirconium ore is a primary ore produced by weathering, crushing and enrichment under natural conditions. It has the advantages of easy mining, easy selection, low production cost, good product quality and many associated minerals, and comprehensive recovery value. It is one of the ideal mineral resources. Titanium lead ore is currently the main source of minerals such as ilmenite, rutile, zircon and monazite in the world. Titanium and zirconium sand mines need to be stripped except for a few layers of the upper part of the ore body. Generally, mining or mining machinery can be used without mining. Dry mining machinery includes: bulldozers, scrapers, loaders and bucket wheel excavators, etc.; the ship used for ship mining has three types: chain bucket type, stirring type and bucket wheel type. The ore is transported to the roughing plant via a belt conveyor or a sand pump pipe. Titanium and zirconium sand ore beneficiation plants are divided into two stages: rough selection and selection.

(1) rough selection

The ore sent to the roughing plant is first subjected to necessary preparations such as slag removal, sieving, grading, de-sludge and concentration, and then selected into the rough selection process. The purpose of rough selection is to separate the ore selected according to different mineral densities, discard the low-density gangue mineral tailings, and obtain a heavy mineral mixed concentrate with a heavy mineral content of about 90%, which is used as a feed for the selected plant. The roughing plant is generally integrated with mining operations to form a mining plant. In order to adapt to the characteristics of sand deposits, the general rough selection plants are all built into mobile type. The mobile modes include floating pontoons and land tracks, crawlers, pallets and regular demolition. Titanium and zirconium sand ore are generally selected from equipments with large processing capacity, high recovery rate and convenient for mobile plant selection. The more common ones are conical concentrators and spiral concentrators, and a small number of shakers are used. The above equipments are used singly or in combination: a single cone concentrator is mainly used for roughing plants with large scale or high mineral content in raw ore; most plants use coarse selection of conical concentrators and re-selection of spiral concentrators; Some smaller concentrators often use a single spiral concentrator for rough selection.

(2) Featured

Titanium and zirconium sand ore are multi-series mineral deposits containing several valuable minerals. The purpose of the selection is to effectively separate and purify the recovered minerals in the coarse concentrate to meet the quality requirements of their respective concentrates. Become a commodity concentrate. The selected plants are generally built in fixed form. The coarse concentrate is transported to the selected plant by means of automobile, train or pipeline transportation. The selected operations are divided into two stages, wet and dry, with dry operations as the mainstay. Depending on the nature of the coarse concentrate, partial wet work is usually used in the early stages of the selective process. Sometimes there are dry and wet processes in the selection process, but from the perspective of energy consumption and streamlined process, we strive to reduce this process under possible conditions. The wet work types of the selected plants are: re-election by shaker or spiral concentrator to further discard the gangue minerals with small density remaining in the coarse concentrate, and for the coarse concentrate containing salt, also have the salt for cleaning. The role of pre-selection of some easy-selected titanium concentrates by wet magnetic separation, reducing dry selection into the ore dressing; adding sodium hydroxide, hydrochloric acid, dilute hydrofluoric acid, sodium metabisulfite, etc. to the coarse concentrate The agent is stirred at a high concentration to achieve the purpose of removing mineral surface contamination and improving the selection effect; the selection of zircon and monazite products is carried out by flotation method.

Dry selection is sorted by the difference in magnetic properties, conductivity, and density of each mineral in the product. Depending on the composition and properties of the coarse concentrate, the structure of the dry selection process varies greatly. For the dry selection of coarse ore concentrates with complex mineral composition and comprehensive recovery of minerals, the process is more complicated, the operation is more, and the process structure changes greatly. For the coarse concentrate with simple mineral composition, the dry selection process is very simple. . Magnetic separation is a magnetic separator with different types and field strengths. Compared with the separation of minerals with different susceptibility, the commonly used magnetic separation equipments are: disc type (single disc, double disc, three discs), cross belt type, roller In the dry-selection process, the weak magnetic separation is first used to select the ferromagnetic mineral-magnetite, and then the medium magnetic field is used to select most of the magnetic and relatively easy-to-select titanium. Iron ore products. Strong magnetic separation is used for the separation of partially weaker ilmenite and monazite from non-magnetic minerals such as zircon, rutile and leucoxene. Electro-election is performed by using the difference in conductivity between minerals in the coarse concentrate. The electric separator used is three types: roll type, plate type and sieve type. Electrification is often used in the rough concentrate dry selection process for the grouping between conductors and non-conducting minerals; the separation of rutile and zircon; the selection of ilmenite and ilmenite, zircon, monazite and other minerals. In the production practice, operating conditions such as changing the magnetic field and electric field strength are sometimes employed to alternate the electrical and magnetic separation operations to enhance the sorting effect.