Iron Ore - Natural mineral formations containing iron and its compounds in such an amount when industrial iron extraction of these formations is advisable. Despite the fact that iron is in a larger or smaller amount of all mountain breeds, under the name of iron ores, only such accumulations of ferrous compounds, of which, with benefits in economicly economical You can get a metal iron.
Iron ores are special mineral formations, which include iron and its compounds. This type of ore is considered an iron if the proportion of this element is contained in such a volume so that its industrial extraction is cost-effective.
In ferrous metallurgy, three main types of iron ore products are used:
- Separated iron ore (low iron content);
- Agloruda (average iron content);
- Pellets (raw iron-containing mass)
The deposits of iron ore are considered rich if the share of iron in them is more than 57%. Poor iron ores may contain a minimum of 26% iron. Scientists allocate two main morphological type iron ore; Linear and flat-like. 
Linear deposits of iron ore are wedge-shaped ore bodies in the zones of terrestrial faults, bends in the process of metamorphosis. This type of iron ore is characterized by a particularly high content of iron (54-69%) with a low content of sulfur and phosphorus.
Flat-like deposits can be found on the tops of ferrous quartzite layers. They belong to the type of weathering.
Rich iron ores are mainly sent to smelting to Marten and converter production or on direct iron reduction.
Main industrial types of iron ore deposits:
- - reservoir sediment fields;
- - complex titaniumagnetite deposits;
- - deposits of ferrous quartzite and rich ores;
- - skarn iron ore deposits;
Secondary industrial types of iron ore deposits:
- - iron ore siderite deposits;
- - iron ore lay-like latheite fields;
- - complex carboatite apatite-magnetite deposits;
The world stocks of explored deposits of iron ore are 160 billion tons, they contain about 80 billion tons of pure iron. The largest deposits The iron ore was found in Ukraine, and the largest stocks of pure iron are located in Russia and Brazil.
The volume of world mining of iron ore is growing every year. In 2010, more than 2.4 billion tons of iron ore were mined, while China, Australia and Brazil provided two thirds of prey. If you add to them Russia and India, then their total share in the market will be more than 80%.
How Ruda is mined
Consider several basic options for mining iron ore. In each case, the choice in favor of this or that technology is made taking into account the location of minerals, the economic feasibility of using one or another equipment, etc.
In most cases, the extraction of ore takes place by a career way. That is, for the organization of production, the deep quarry is first breaking down in approximately 200-300 meters deep. After that, right from its bottom on large machines is exported iron ore. Which immediately after production on diesel locomotives is transferred to various combines, where steel is manufactured from it. Today many large companies Ore mining, if they have everything needed equipment for such work.
Ring quarry should be used using large excavators, but it should be considered that this process can take away from you quite many years. After excavators do the very first plastic of the iron ore, it is necessary to pass it on the analysis of experts so that they can determine which percentage of iron contains. If this percentage is at least 57, then the decision to mining ore in this area will be a cost-effective. Such ore can be safely transported to the combines, because after processing it will necessarily get high quality steel.
However, this is not all, it should be very carefully checked steel, which appears as a result of iron ore processing. If the quality of the mined ore will not comply with European standards, then it should be understood how to improve the quality of production.
The lack of an open method is that it allows you to extract iron ore only at a relatively small depth. Since it is often somewhat deeper - at a distance of 600-900 m from the surface of the Earth - you have to build mines. First make the shaft barrel, which resembles a very deep well with reliably fortified walls. From the trunk in different directions, corridors are departed, which are called shtracks. The iron ore found in them exploded, and then her pieces with special equipment raised to the surface. This method of mining of iron ore is effective, but at the same time is associated with serious danger and cost. 
There is another way to extract iron ore. It is called SRS or downhill hydroda. The ore is removed from under the ground as follows: Buryat deep well, lowered the pipes with the hydromonitor and with the help of a very strong water jet will crush the breed, and then raise it to the surface. This method is safe, however, unfortunately, it is still ineffective. Thanks to this method, only about 3% of iron ore can be obtained, while with the help of mines, approximately 70% is mined. However, specialists are engaged in the development of the well hydroda hydroda industry, and therefore it is hope that in the future it is this option that will be the main one, providing careers and mines.
Iron ore is a special mineral formation, including iron, as well as its compounds. Ruda consider iron if it contains this element in sufficient volumes in order to be economically beneficial to extract it.
The main type of iron ore is it contains almost 70% of oxide and iron zaksi. This ore has a black or gray-steel color. Magnetic Zheleznyak in Russia is mined in the Urals. It is found in the depths high, grace and Kachkanar. In the territory of Sweden, it is found in the vicinity of Falun, Danaeor and Gellivar. In the US, it is Pennsylvania, and in Norway - rental and Persberg.
In ferrous metallurgy, iron ore products are separated by three types:
Separated iron ore (low iron content);
Aglorud (with an average iron content);
Popes (raw iron-containing mass).
Morphological types
We are rich with such deposits of iron ore, which contain more than 57% of iron in their composition. Poor ores include those in which at least 26% of iron. Scientists divided iron ore into two morphological types: linear and flat-like.
The iron ore of the linear type is ore wedge-shaped bodies in the zones of bends and earth faults. This type is characterized by a particularly large content of iron (from 50 to 69%), but sulfur and phosphorus in such a ore is contained in a small amount.
Flat-like deposits are found on the tops of ferrous quartzite layers, which are a typical eloquence.
Iron ore. Application and mining
Rich iron ore application is found to obtain cast iron and mainly goes on the smelting into converter and Martin production or directly on the restoration of iron. A small amount is used as natural paint (ocher) and cradle clay
The volume of world stocks of explored deposits amounted to 160 billion tons, and iron contains about 80 billion tons. The iron ore was found in Ukraine, and Russia and Brazilian possesses the largest pure iron reserves.
The volume of world mining of ores grow every year. In most cases, iron ore is mined by an open method, the essence of which is that all necessary techniques are delivered to the field, and a quarry is built there. The depth of the career is an average of about 500 m, and its diameter depends on the features of the found deposit. After that, with the help of special equipment, iron ore is extracted, fold on machines adapted for the transport of heavy loads, and deliver from a career to enterprises that are recycled.
The disadvantage of the open method is the ability to extract ore only at a small depth. If it lies much deeper, you have to build the mines. First they make a trunk, resembling a deep well with a well fortified walls. In different directions, corridors are departed from the trunk, the so-called Shtreki. The ore found in them is exploded, and then her pieces rise to the surface with the help of special equipment. Extraction of iron ore in this way is effective, but is associated with serious danger and costs.
There is another way, with which iron ore is mined. It is called SRS or downhill hydroda. The ore is extracted from under the ground in this way: it is a borehide, lowered pipes with a hydromonitor and a very powerful water jet will crush the rock, which is then raised to the surface. The mining of iron ore is safe, however, unfortunately, ineffective. It is possible to obtain only 3% of ore, and 70% is mined with mines. However, the development of the CSD method is improved, and there is a high probability that in the future this option will be the main one, providing the mine and career.
Iron Ore - Natural mineral formations containing iron and its compounds in such an amount when industrial iron extraction of these formations is advisable. Despite the fact that iron is in a larger or smaller amount of all rocks, only such accumulations of ferrous compounds understand the name of iron ores, of which metal iron can be obtained in economically.
Classification
The following industrial types of iron ores differ:
There are four main types of iron ore products used in black metallurgy:
- separated iron ore (enriched by the separation method crumbling ore),
- iron ore briquettes.
Chemical composition
By chemical composition Iron ores are oxides, hydrates of oxides and carbonic salts of iron zaksi are found in nature in the form of a variety of ore minerals, of which the most important: magnetite, or magnetic Zheleznyak; Hematite, or iron brilliance (Red Zheleznyak); Limonite, or brown Zheleznyak, to which marsh and lake ores include; Finally, Siderita, or Puttish Zheleznyak (Iron Speat), and its species of spherosiderite. Commodably every accumulation of these ore minerals represents a mixture of them, sometimes very close, with other minerals that are not containing iron, such as, for example, with clay, limestone, or even with component parts crystalline erupted rocks. Sometimes in the same field there are some of these minerals together, although in most cases some one prevails, while others are associated with it genetically.
Rich iron ore
Rich iron ore has iron content over 57%, and silica is less than 8-10%, sulfur and phosphorus less than 0.15%. It is a product of natural enrichment of ferrous quartzite, created due to the leaching of quartz and the decomposition of silicates in the processes of long weathering or metamorphosis. Poor iron ores may contain a minimum of 26% iron.
Two main morphological types of deposits of rich iron ore are distinguished: flat-like and linear. Flat-like roaming on the tops of the coopolding layers of ferrous quartzites in the form of significant in the area with a pocket-like sole and belong to the type of weathering cables. Linear deposits are falling in the depth of clignless ore bodies of rich ores in the zones of faults, fractures, crushing, bends in the process of metamorphosis. Ore is characterized by a high content of iron (54-69%) and a low content of sulfur and phosphorus. The most characteristic example of metamorphous fields of rich ores can be the Pervomaiskoy and yellow deposits in the northern part of Krivbassa.
Rich iron ores go to the smelting of cast iron in domain furnaces, which is then reworked into steel in Marten, converter or electrostalleaval production. A small part of the mined rich iron ores is used as dyes and weighting agents for drilling mud. Separately allocate the processes of direct reduction of iron, one of the product of which is hot-chicken iron. Poor and average ore content of ore for industrial use should be pre-pass through the process of enrichment.
Factors defining the value of ores
- The main factor determining the metallurgical value of iron ore is iron content. Iron ores on this feature are divided into rich (60-65% FE), with an average content (45-60%) and poor (less than 45%). Reducing the amount of iron in ore causes a progressive decrease in its metallurgical value due to a significant increase in the relative release of slag in the domain melting. The practice of working blast furnaces is established that with an increase in the content of iron in the mixture by 1% (ABS) The furnace capacity increases by 2-2.5%, and the specific coke flow rate is reduced by 1-1.5%.
- The composition of the empty breed has a significant impact on the quality of iron ore. With the basicity of the empty rock, equal to zero, the amount of slag is doubled compared to the amount of empty breed made by ore. If the empty ore breed is self-control, that is, the basicity of ore and slag is equal, then the injection of the flux is not required, and the amount of slag is equal to the number of empty breed, that is, it will be twice as well. In proportion to the decrease in slag yield, the specific coke consumption is reduced and the productivity of the blast furnace increases. Thus, the metallurgical value of ore increases with an increase in the basicity of the empty breed.
- Harmful impurities reduce the value of ore, and when significant quantity Make it unsuitable for direct use in the blast furnace even with a high content of iron.
- In the process of domain melting, a small number of sulfur compounds enters the gas and is carried out from the furnace, but the bulk of the sulfur is distributed between the cast iron and slag. To translate maximum amount Sulfurs in the slag and prevent the production of sulfur cast iron, there must be highly infinited slags in the blast furnace, which ultimately increases the specific coke consumption and proportionally reduces the furnace performance. It is believed that the decrease in the sulfur content in the ore part of the charge by 0.1% (ABS) reduces the specific consumption of coke by 1.5-2%, the flow consumption is 6-7% and 1.5-2% increases the productivity of the domain Furnaces. The current conditions limit the maximum sulfur content in ore intended for the domain melting, a value of 0.2-0.3%. However, due to the fact that at present, the main mass of the mined ores is subjected to enrichment, followed by thermal processing of concentrates in the process of agglomeration or firing the peese, as a result of which a significant proportion of the original sulfur (80-95%) burns out, it became possible to use Iron ores with sulfur content up to 2-2.5%. At the same time, the ore, which includes a sulfide sulfur, would be more value compared to ore, sulfur in which sulfates are in the form of sulfates, since the latter is deleted worse in the form of sulfates.
- Even worse with agglomeration, arsenic is removed. In blasting, it fully goes to cast iron. The content of arsenic in the mined ore should not exceed 0.1-0.2%, even if it goes to the agglomeration.
- Phosphorus during agglomeration is not deleted. In the blast furnace, it fully goes into cast iron, so its limit content in ore is determined by the possibility of smearing the cast iron of this variety. So, for non-worker (pure phosphorus) cast iron, its amount in ore should not exceed 0.02%. On the contrary, when obtaining phosphorous cast iron for Tomasovsky redistribution, it should be 1% and higher. The average of the phosphorus, equal to 0.3-0.5%, is most adversely, since it is too large for smelting of Thomasy castoffs, and for non-workers, which leads to a deterioration in the technical and economic indicators of the steel-smelting process.
- Zinc during agglomeration is not deleted. Therefore, the technical conditions limit the content of zinc in the quantitative ores of 0.08-0.10%.
- Useful impurities increase the metallurgical value of iron ores for the following reasons. In the carrier of such ores, natural-fledged cast iron can be obtained, and then steels that do not require the introduction of special expensive additives for doping (or reduced consumption). This uses nickel and chromium impurities in ores. In other cases, different valuable metals are obtained simultaneously with the cast iron. For example, when processing titanagnetite ores as a result of metallurgical redistribution, except for iron, a very valuable and expensive metal - vanadium is extracted, due to which it becomes cost-effective processing raw materials with low iron content ( see for example Kachkanarsky GOK). Increased manganese in iron ores Allows you to obtain manganese cast iron, in which the desulfuraction processes are fully passable, the quality of the metal is improved.
- The ability of ore enriched (ore enrichability) is an important sign of its metallurgical value, since most of the mined iron ores are subjected to one or another methods of enrichment in order to increase the content of iron or reduce the concentration of harmful impurities. The process of enrichment lies in a more or less complete separation of the ore mineral from the empty breed, sulphides. The enrichment is facilitated if the empty breed almost does not contain iron, and the particles of the ore mineral are relatively large grains. These ores belong to the category easy enriched. Thin enclosure of ore particles and a large amount of iron in an empty breed make ore difficult-upwhich significantly reduces its methamalgic value. According to enrichment separate types Ruds can be positioned in the next row in the order of its deterioration: Magnetic Zheleznyaki (enriched with the cheapest and effective way - magnetic separation), hematite and mardite ores, brownie ironing, seerites. An example of an easier ore can serve as the magnetites of the Olenegorsk deposit. Magnetic separation makes it easy to separate the quartz of the empty breed from magnetite. When iron content in the initial ore, 29.9% is obtained with a concentrate with 65.4% iron. Also, with the magnetic separation of the titanagnetites of the Kachkanar field, the share of iron in which 16.5% is obtained by a concentrate with 63-65% iron. To the discharge of difficult-rich ores can be attributed, for example, Kerch brown troops, washing with which, with the initial iron content, 40.8% allows you to increase it in concentrate only to 44.7%. In the washed of the ore of the empty breed, its share reaches 29-30%. The metallurgical value of iron ore increases, when other useful components are retrieved during it, other useful components are extracted. For example, when enriching the ore-akdorne deposit, except for iron ore concentrate, an apatite concentrate is obtained, which is a raw material for production. mineral fertilizer. Such. comprehensive processing Extraked from the depths of iron ore significantly increases the profitability of the development of the deposit.
- To the mainstream physical propertiesaffecting the metallurgical value of iron ores belong: strength, granulometric composition (rudeness), porosity, moisture intensity, etc. Direct use of low-strength and dusty ores in domain furnaces is impossible, since their small fractions deteriorate greatly worsen the gas permeability of the charged materials. In addition, the domain gas flow makes the Outlet particles of less than 2-3 mm in size from the working space, which are then settled in dust collectors. When processing low-stage ores, this leads to an increase in their specific consumption for the smelting of cast iron. The mining of loose dusty ores is associated with the need to build costly agglomerating factories for their eyepieces, which significantly devalues \u200b\u200bsuch ores. The number of little things is particularly large in the extraction of brown iron and hematite ores. Thus, the rich ores of the Kursk magnetic anomaly during mining give up to 85% of the little things in need of ocked. The average fraction output is larger than 10 mm (suitable for domain melting) from rich krivorvoy ores does not exceed 32%, and the output of the fraction is larger than 5 mm from the mined Kerch ores - no more than 5%. Under the terms of the domain melting, the lower limit of ore loads loaded into the blast furnace should be 5-8 mm, but due to the difficulty of eliminating such small fractions, especially wet ores, it increases to 10-12 mm. The upper limit of sizes of pieces is determined by the restability of ore and should not exceed 30-50 mm, but in practice there are 80-100 mm.
- RUD strength during drying, heating and recovery. Due to the fact that the ore includes mineral components with various thermal expansion coefficients, with heating in ore slices there are significant internal stresses, causing their destruction with the formation of trivia. Too fast drying can cause the destruction of ore pieces under the action of the highlighted water vapor. Reducing the strength of iron ore materials during drying and heating is called decoration.
- Important technological quality of iron ores are their softening. In the blast furnace the tough masses of slag formed during the softening of the ore part of the charge, create a large resistance to the passage of gases. Therefore, it is desirable to use ores with the most high temperatures The beginning of softening. In this case, the ore does not soften in the shaft of the blast furnace, which favorably affects the gas permeability of the charge pole. The shorter the ore softening interval (the temperature difference between the beginning and the end of the softening), the faster the softened the tough masses are converted into a liquid movable melt, which does not represent a large resistance for the stream of gases. Therefore, the ores with a short interval and high temperature of the beginning of softening have a greater metallurgical value.
- The moisture content of ore determines its humidity. For different types Iron ONDs permissible humidity, taking into account their moisture intensity, is established by technical conditions: for brownie zheleznyakov - 10-16%, gematite ores - 4-6%, magnetites - 2-3%. Improving moisture increases transportation costs for transportation of ore, and in winter time Requires drying costs to eliminate its fatigue. Thus, with increasing moisture and moisture mixer, their metallurgical value is reduced.
- The nature of the porosity of ore largely determines the reaction surface of the interaction of gaseous reducing agents with ore iron oxides. Distinguish the overall and open porosity. With the same value of general porosity with a decrease in the pore size, the reaction surface of the pieces of ore increases. This, with other things being equal, increases the reduction of ore and its metallurgical value.
- Restored ores call its ability with a greater or lesser speed to give oxygen associated with iron in its oxides, gaseous reducing agent. The higher the registrability of ore, the less may be the time of her stay in the blast furnace, which makes it possible to speed up the melting. With the same time of staying in the furnace, there are more oxygen-related oxygen associated with hardware with stove gases. This reduces the degree of development of direct recovery and the specific consumption of coke for the smelting of cast iron. Thus, from any point of view, the increased redundancy of ore is its valuable property. The greatest restorations are usually loose, high-porcelain railings and siderites, which, when removing CO 2 in the upper horizons of a blast furnace or as a result of preliminary firing, acquire high porosity. For them, more dense hematitis and magnetite ores are followed in order to reduce the restority.
- The size of the iron ore field is an important criterion for its assessment, since the profitability of its development increases with an increase in ore reserves, the economy of the construction and operation of basic and auxiliary structures (quarries, mines, communications, housing, etc.) increases. The domain shop of the modern metallurgical plant of the average power flows 8-10 million tons of cast iron per year, and its annual need for ore is 15-20 million tons. In order to compensate for the construction costs, the plant should work at least 30 years (depreciation). This corresponds to the minimum reserves of the 450-600 million tons deposit.
- The conditions of mining, depending on the nature of the ore body location, have a significant effect on the definition of the marrow limit on the iron content. The deep linking of ore reservoirs requires the construction of expensive mines for their development, large operating costs (on ventilation, coverage of mines, water pumping, raising ore and empty breed, etc.). An example of an extremely unfavorable mining and geological conditions of the ore body of the ore body can serve as the Yakovlevskoye deposit of KMU, in which the height of the roof over ore reaches 560 m in some sections. Eight aquifers are located in the roof, which creates heavy hydrogeological conditions for mining and requires a removal underground water From the area of \u200b\u200bore deposits or artificial freezing of the soil in the area. All this requires large capital and operating costs for the extraction of ore and reduces the value of ore. Local from the field near the day surface of the Earth and the possibility of mining ore open way (Careers) significantly reduce the extraction of ore and increase the value of the deposit. In this case, it becomes cost-effective to produce and recycle ores with lower iron content than under the underground mining.
- Along with data on the number and quality of iron ore an important factor In assessing this or that field is its geographic and economic location: remoteness from the consumer, the availability of transport communications, labor resources etc.
Industrial types of deposits
Main industrial types of iron ore deposits
- Deposits of ferrous quartzite and rich ores formed on them
Have metamorphic origin. Ruda is represented by ferrous quartzite, or jespilles, magnetite, hematite-magnetite and hematite-martite (in the oxidation zone). Pools of Kursk Magnetic Anomaly (KMA, Russia) and Krivoy Rog (Ukraine), Lake Upper Lake (eng.)russian (USA and Canada), Hammersley Rubber Equipment (Australia), Minas Gerais (Brazil) district.
- Plastic sediment fields. Have chemogenic origin, formed by falling out of iron from colloidal solutions. These are oolithic, or legumes, iron ores represented mainly in gently and hydrogenetite. Larring pool (France), Kerch pool, Lisakovskoe et al. (Former USSR).
- Skarn iron ore deposits. Sarbai, Sokolovsky, Kacharskaya, Mount Grace, Magnitogorskoye, Tashtagolskoe.
- Complex titanoagnetite deposits. The origin of the magmatic, the deposits are confined to major Precambrian intrusions. Ore minerals - magnetite, titanomagnetite. Kachkanar, Kusinskoye deposits, Canada deposits, Norway.
Secondary industrial types of iron ore deposits
- Complex carbonatite apatite-magnetite deposits. Kovdorskoe.
- Iron ore magnetic magnetite deposits. Korshunovsky, Rudnogorskoye, Nenundy.
- Iron ore siderite deposits. Bakalskoe, Russia; Ziegerland, Germany, etc.
- Roleberry and iron ordered oxide reservoir fields in volcanogenic and sedimentary strata. Karazhalskoe.
- Iron ore lay-like latheite deposits. Southern Urals; Cuba and others.
Stocks
The global explored stocks of iron ore are about 160 billion tons, which contain about 80 billion tons of pure iron. According to the US geological service, the deposits of the iron ore of Brazil and Russia accounted for 18% of world iron reserves. Reserves in terms of iron content.
Iron content in industrial ores from 16 to 72%. Among the useful impurities Ni, CO, Mn, W, Mo, Cr, V, etc., among harmful - S, R, Zn, Pb, as, Cu. Iron ores on genesis are divided into, and (see map).
Main iron ores
Industrial types of iron ore are classified according to the predominant ore mineral . Magnetite ores are composed of magnetite (sometimes magnetic - magnetomete, often martitisated - turned into hematite during oxidation). They are most characteristic of carbonatite, skarn and hydrothermal deposits . Of carbonatite deposits Along the way extract apatite and baddeleit from the skarn - cobalt-containing pyrite and non-ferrous metals sulphides. Comprehensive (Fe-Ti-V) Titanoagnetite ores are a special kind of magnetite ores. magmatic deposits . Hematite ores, composed mainly by hematite, to a lesser extent by magnetite, are distributed in kore Weathered ferrous quartzitov (martite ores), in skarn, hydrothermal and volcanogenic and sedimentary ores. Rich hematite ores contain 55-65% FE and up to 15-18% Mn. Sideressive ores are divided into crystalline siderite ores and clay wipe rails; They are often magnesian (magnesiateritis). Meet hydrothermal, sedimentary and volcanogenic sediment fields. The average content in them fe 30-35%. After finger Sideressive ores, as a result of removal of CO 2, produce fine iron oxide concentrates containing 1-2%, sometimes up to 10% Mn. In the oxidation zone, siderite ores turn into brown Zheleznyaki. Silicate iron ores are stacked by ferrous chlorite (, leptochlorite, etc.), accompanied by iron hydroxides, sometimes. Forming sedimentary deposits. The average content of FE 25-40% in them. Admixt sulfur insignificant phosphorus up to 1%. Often have a olith texture. In the cortex of weathered turn into brown, sometimes in red (hydrohematite) ironcles. Brown glazes are composed of iron hydroxides, most often hydrogenate. Forming sedimentary deposits (sea and continental) and weathering cortex deposits. Sedimentary ores often have a solid texture. The average FE content in ores is 30-35%. In the brownie zone of some deposits (Bakalskoe in CCCP, Bilbao in Spain et al.) Contains up to 1-2% Mn and more. In the natural-doped brownie products formed in the weathering barks of ultrasound rocks, 32-48% FE, up to 1% Ni, up to 2% CR, hundredths of the percentage of CO, V. From such ores without additives, chromonichel cast iron and low-alloy steel are added. (, Irony) - poor and mean by iron content (12-36%) Metamorphized iron ores, isolated by thin alternating quartz, magnetite, hematite, magnetite-hematic and seerite assesses, places with admixtures of silicates and carbonates. Different with low content of harmful impurities (S and R - hundredths of percent). The field of this type usually possess unique (over 10 billion tons) or large (over 1 billion tons) ore reserves. In the weathered crust of silica, and large deposits of rich hematito-martite ore arise.
The greatest reserves and volumes of production fall on the Precambrian ferrous quartzites and the rich iron ores formed on them are less common, sedimentary bureauless ores, as well as skarn, hydrothermal and carbonatite magnetite ores.
Enrichment of iron ore
There are rich (over 50% FE) and poor (less than 25% FE) ores requiring. For high-quality characteristics of rich ores important It has the content and ratio of non-metallic impurities (slag-forming components), which expressed the basicity coefficient and the flint module. Largest primary coefficient (the ratio of oxide content calcium and magnesium By the amount of oxides silicon and) iron ores and their concentrates are divided into acidic (less than 0.7), self-fluxes (0.7-1.1) and main (more than 1,1). The best are self-flowing ores: sour ores compared to the basic require an introduction to a domain embezzlement of increased quantity limestone (Flice). On the flint module (the ratio of silicon oxide content to aluminum oxide) The use of iron ore is limited to the types of ores with the module below 2. To poor ores requiring enrichment include titanagnetite, magnetite, as well as magnetite quartzites with an FE magnetite content of more than 10-20%; Martitite, hematite and hematitic quartzites with a FE content of more than 30%; Siderites, hydrogenated and hydrogerate-leptochlorite ores with a FE content of more than 25%. Lower limit of FE in common and magnetite for each deposit, taking into account it scale , mining, I. economic conditions Mounted Conditions.
Ore, requiring enrichment, are divided into easy and hurt and difficult, which depends on their mineral composition and textural-structural features. Magnetite ores and magnetites include easier ores quartz , to difficult-to-rude - iron ores in which iron is associated with hikingrystalline and colloidal formations, in them grinding Cannot open ore minerals Because of their extremely small sizes and fine germination with nonmetallic minerals. The choice of enrichment methods is determined by the mineral composition of ores, their textural-structural features, as well as the nature of non-metallic minerals and the physico-mechanical properties of ores. Magnetite ores are enriched with a magnetic way. Application dry and wet magnetic separation Provides conditional concentrates even with a relatively low iron content in the original ore. If there is in rules industrial content Hematite along with magnetite is used magnetic flotation (for thin-crushed ores) or magnetic gravitational (for large-paved ores) methods of enrichment. If in magnetite ores is contained in industrial quantities apatite or sulphides, medical and zinc , Minerals. bora and others, then to extract them from waste magnetic separation Applied flotation . The enrichment schemes of titaniumagnetite and ilmenite-titaniumagnetite ores include multi-stroke wet magnetic separation. For the purpose of allocation ilmenita The titanium concentrate is enrichment of waste of wet magnetic separation by flotation or gravitational method, followed by magnetic separation in field High intensity.
Magnetite quartzite enrichment schemes include splitting up , grinding and magnetic enrichment in a weak field. The enrichment of oxidized ferrous quartzite can be produced by a magnetic (in a strong field), firing immigration and flotation methods. For enrichment of hydrogenate-leptochlorite oolithic brownie zheleznyakov, a gravitational or gravitational magnetic (in a strong field) is used, studies are also conducted by enrichment of these ores by a firing magnitude. Clay hydrogenate and (wounded) ores are enriched flushing . The enrichment of seerite ores is usually achieved by the firing. In the processing of ferrous quartzite and skarn-magnetite ores, concentrates are usually obtained with a content of FE 62-66%; In the conditioning concentrates wet magnetic separation from apatite-magnetite and magnetic iron ores of iron at least 62-64%; For electrometallurgical concentrates, concentrates with FE content are not lower than 69.5%, SiO 2 no more than 2.5%. The concentrates of gravitational and gravitational and magnetic enrichment of oolithic brown railways are considered conditioned with the content of Fe 48-49%; As it improves the methods of enriching the requirements for concentrates from ores increase.
Most of the iron ores are used to smell cast iron. A small amount serves as natural colors (ocher) and drilling weights clay solutions.
Stocks of iron ore
According to the reserves of iron ores (balancing - over 100 billion tons), CCCP takes 1st place in the world. The largest stocks of iron ores in CCCP are concentrated in Ukraine, in central regions RSFSR, in Northern Kazakhstan, in the Urals, in Western and Eastern Siberia. . Of overall The explored reserves of iron ores of 15% are rich, not requiring enrichment, 67% - enriched in simple magnetic schemes, 18% requiring complex methods of enrichment.
KHP, DPRK. and CPB have significant reserves of iron ores sufficient to develop their own black metallurgy. see also
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