What are ores? Deposit of iron ore. Ores of Russia. Metal ores and their classification What are the ores

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Metal ores and their classification

metal ore is a mineral containing valuable metals in quantities that are beneficial for industrial processing.

Ferrous metals include iron, manganese, chromium, titanium, vanadium. Deposits of iron ore are classified as industrial with a metal content of at least several tens of millions of tons and a shallow occurrence of ore bodies. In large deposits, the iron content amounts to hundreds of millions of tons. Most of the ore (in million tons) is mined in China (250), Brazil (185), Australia (more than 140), Russia (78), USA and India (60 each) and Ukraine (45).

Classification of ferrous metal ores:

b Hematite ores (red iron ore) are iron oxide with an iron content of 51 ... 66%, moisture - 1.6 ... 7%.

b Magnetite ores (magnetic iron ore) are complex oxides of iron. The iron content ranges from 50 ... 60%, moisture - 2 ... 12%.

b Brown iron ore - ores of iron hydroxide. The average iron content is 30-55%, moisture 8-18%.

b Iron pyrite (pyrite, sulfur pyrite) is a golden-yellow ore with a metallic luster, contains up to 44% iron and up to 52% sulfur. ore metal non-ferrous deposit

Non-ferrous metals are divided into two main groups:

light (aluminum, magnesium, titanium);

heavy (copper, zinc, lead, nickel, cobalt).

Aluminum dominates among light non-ferrous metals in terms of production and consumption volumes. Russia has large reserves of non-ferrous metal ores. Their distinctive feature is the extremely low percentage of metal contained in them. Therefore, the ores of almost all non-ferrous metals are enriched. The main reserves are located in the Urals, Western and Eastern Siberia, the Far East and other regions of the country.

Classification of non-ferrous metal ores:

b Ferromanganese - an alloy containing more than 10% iron and less than 10% manganese

b Chrome ore contains 13-61% chromium, 4-25% aluminum, 7-24% iron, 10-32% magnesium and other components

b Bauxite ores contain 50-60% alumina, which contains up to 37% aluminum.

b Alumina - a product of bauxite processing, a white polydisperse powder, due to the high content of aluminum oxide, is the main raw material for the aluminum industry.

Methods for obtaining a useful element by chemical means.

1. Concentration

Many ores contain unwanted materials such as clay and granite, also known as gangue. Thus, metal extraction is to remove this waste rock.

2. Method of underground leaching

The method of extracting a mineral by selective dissolution of its chemical reagents in the ore body in situ with extraction to the surface. PV is used for the extraction of non-ferrous metals.

3. Recovery

The extraction of metals in this way consists in the restoration of their ores to a metallic state. Metals that exist in nature as oxide ores can be reduced with carbon or carbon monoxide.

4. Electrolysis

Metals belonging to the upper part of the voltage range are usually recovered by electrolysis of their molten ores. These metals include aluminum, magnesium and sodium.

5. Refining

Purification of metals from impurities using electrolysis, when the crude metal is the anode, and the purified metal is deposited on the cathode.

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Ore: definition and features

Ores are rocks that are used to process and extract the metals they contain. The types of these minerals differ in origin, chemical content, concentration of metals and impurities. The chemical composition of the ore contains various oxides, hydroxides and carbonic salts of iron.

Interesting! Ore has been in demand in the economy since ancient times. Archaeologists managed to find out that the manufacture of the first iron objects dates back to the 2nd century BC. BC. For the first time this material was used by the inhabitants of Mesopotamia.

Iron is a common chemical element in nature. Its content in the earth's crust is about 4.2%. But in its pure form, it is almost never found, most often in the form of compounds - in oxides, iron carbonates, salts, etc. Iron ore is a combination of minerals with a significant amount of iron. In the national economy, the use of ores containing more than 55% of this element is considered economically justified.

What is made from ore

iron ore industry— the metallurgical industry, which specializes in the extraction and processing of iron ore. The main purpose of this material today is the production of iron and steel.

All products made from iron can be divided into groups:

Pig iron with high carbon concentration (above 2%).
Cast iron.
Steel ingots for the manufacture of rolled products, reinforced concrete and steel pipes.
Ferroalloys for steel smelting.

What is ore for?

The material is used for smelting iron and steel. Today there is practically no industrial sector that does without these materials.

Cast iron It is an alloy of carbon and iron with manganese, sulfur, silicon and phosphorus. Pig iron is produced in blast furnaces, where the ore is separated from iron oxides at high temperatures. Almost 90% of the iron produced is marginal and is used in steel smelting.

Various technologies are used:

electron-beam smelting to obtain pure high-quality material;
vacuum processing;
electro-slag remelting;
steel refining (removal of harmful impurities).

The difference between steel and cast iron is the minimum concentration of impurities. For purification, oxidative smelting in open-hearth furnaces is used.

The highest quality steel is smelted in electric induction furnaces at extremely high temperatures.

Ore differs in the concentration of the element contained in it. It is enriched (with a concentration of 55%) and poor (from 26%). Poor ores should be used in production only after enrichment.

By origin, the following types of ores are distinguished:

Magmatogenic (endogenous) - formed under the influence of high temperature;
Surface - the settled remains of the element at the bottom of sea basins;
Metamorphogenic - obtained under the influence of extremely high pressure.

The main compounds of minerals with iron content:

Hematite (red iron ore). The most valuable source of iron with an element content of 70% and with a minimum concentration of harmful impurities.
Magnetite. A chemical element with a metal content of 72% or more is distinguished by high magnetic properties and is mined at magnetic iron ore.
Siderite (iron carbonate). There is a high content of waste rock, the iron itself in it is about 45-48%.
Brown ironstones. A group of aqueous oxides with a low percentage of iron, with impurities of manganese and phosphorus. An element with such properties is distinguished by good reducibility and porous structure.

The type of material depends on its composition and the content of additional impurities. The most common red iron ore with a high percentage of iron can be found in a different state - from very dense to dusty.

Brown ironstones have a loose, slightly porous structure of brown or yellowish color. Such an element often needs to be enriched, while it is easily processed into ore (high-quality cast iron is obtained from it).

Magnetic iron ore is dense and granular in structure and looks like crystals interspersed in the rock. The shade of the ore is a characteristic black-blue.

How ore is mined

Iron ore mining is a complex technical process that involves diving into the earth's interior in order to search for minerals. To date, there are two ways to extract ore: open and closed.

Open (quarry method) is the most common and safest option compared to closed technology. The method is relevant for those cases when there are no hard rocks in the working area, and there are no settlements or engineering systems nearby.

First, a quarry is dug out up to 350 meters deep, after which iron is collected and removed from the bottom by large machines. After mining, the material is transported by diesel locomotives to steel and iron factories.

Quarries are dug by excavators, but such a process takes a lot of time. As soon as the machine reaches the first layer of the mine, the material is submitted for examination to determine the percentage of iron content and the feasibility of further work (if the percentage is above 55%, work in this area continues).

Interesting! Compared to the closed method, mining in quarries costs half as much. This technology does not require the development of mines or the creation of tunnels. At the same time, the efficiency of work in open pits is several times higher, and material losses are five times less.

Closed mining method

Mine (closed) ore mining is used only if it is planned to preserve the integrity of the landscape in the area where ore deposits are being developed. Also, this method is relevant for work in mountainous areas. In this case, a network of tunnels is created underground, which leads to additional costs - the construction of the mine itself and the complex transportation of metal to the surface. The main drawback is the high risk to the lives of workers, the mine can collapse and block access to the surface.

Where is the ore mined

The extraction of iron ore is one of the leading areas of the economic complex of the Russian Federation. But despite this, Russia's share in world ore production is only 5.6%. World reserves are about 160 billion tons. The volume of pure iron reaches 80 billion tons.

countries rich in ores

The distribution of fossils by country is as follows:

Russia - 18%;
Brazil - 18%;
Australia - 13%;
Ukraine - 11%;
China - 9%;
Canada - 8%;
USA - 7%;
other countries - 15%.

Significant deposits of iron ore are noted in Sweden (the cities of Falun and Gellivar). In America, a large amount of ore has been discovered in the state of Pennsylvania. In Norway, metal is mined in Persberg and Arendal.

Ores of Russia

The Kursk magnetic anomaly is a large iron ore deposit in the Russian Federation and in the world, in which the volume of crude metal reaches 30,000 million tons.

Interesting! Analysts note that the scale of mining at the KMA mines will continue until 2020, and then there will be a decline.

The mine area of the Kola Peninsula is 115,000 sq. km. Iron, nickel, copper ores, cobalt and apatite are mined here.

The Ural Mountains are also among the largest ore deposits in the Russian Federation. The main area of development is Kachkanar. The volume of ore minerals is 7000 million tons.

To a lesser extent, metal is mined in the West Siberian basin, in Khakassia, the Kerch basin, in Zabaikalsk and the Irkutsk region.

Iron ore began to be mined by man many centuries ago. Even then, the advantages of using iron became obvious.

Finding mineral formations containing iron is quite easy, as this element makes up about five percent of the earth's crust. Overall, iron is the fourth most abundant element in nature.

It is impossible to find it in its pure form, iron is contained in a certain amount in many types of rocks. Iron ore has the highest iron content, the extraction of metal from which is the most economically profitable. The amount of iron contained in it depends on its origin, the normal proportion of which is about 15%.

Chemical composition

The properties of iron ore, its value and characteristics directly depend on its chemical composition. Iron ore may contain varying amounts of iron and other impurities. Depending on this, there are several types of it:

very rich when the iron content in ores exceeds 65%;
rich, the percentage of iron in which varies from 60% to 65%;
medium, from 45% and above;
poor, in which the percentage of useful elements does not exceed 45%.

The more side impurities in the composition of iron ore, the more energy is needed for its processing, and the less efficient is the production of finished products.

The composition of the rock may be a combination of various minerals, waste rock and other impurities, the ratio of which depends on its deposit.

Magnetic ores are distinguished by the fact that they are based on an oxide that has magnetic properties, but with strong heating they are lost. The amount of this type of rock in nature is limited, but the iron content in it may not be inferior to red iron ore. Outwardly, it looks like solid crystals of black and blue.

Spar iron ore is an ore rock based on siderite. Very often it contains a significant amount of clay. This type of rock is relatively hard to find in nature, which, given the small amount of iron content, makes it rarely used. Therefore, it is impossible to attribute them to industrial types of ores.

In addition to oxides, other ores based on silicates and carbonates are found in nature. The amount of iron content in the rock is very important for its industrial use, but the presence of useful by-products such as nickel, magnesium, and molybdenum is also important.

Application industries

The scope of iron ore is almost completely limited to metallurgy. It is used mainly for the smelting of pig iron, which is mined using open-hearth or converter furnaces. Today, cast iron is used in various spheres of human activity, including in most types of industrial production.

Various iron-based alloys are used to no lesser extent - steel has found the widest application due to its strength and anti-corrosion properties.

Cast iron, steel, and various other iron alloys are used in:

Mechanical engineering, for the production of various machine tools and apparatus.
Automotive industry, for the manufacture of engines, housings, frames, as well as other components and parts.
Military and missile industries, in the production of special equipment, weapons and missiles.
Construction, as a reinforcing element or erection of load-bearing structures.
Light and food industry, as containers, production lines, various units and devices.
Mining industry, as special machinery and equipment.

Iron ore deposits

The world's iron ore reserves are limited in quantity and location. The areas of accumulation of ore reserves are called deposits. Today, iron ore deposits are divided into:

Endogenous. They are characterized by a special location in the earth's crust, usually in the form of titanomagnetite ores. The forms and locations of such inclusions are varied, they can be in the form of lenses, layers located in the earth's crust in the form of deposits, volcano-like deposits, in the form of various veins and other irregular shapes.
Exogenous. This type includes deposits of brown iron ore and other sedimentary rocks.
Metamorphogenic. Which include quartzite deposits.

Deposits of such ores can be found throughout our planet. The largest number of deposits is concentrated on the territory of the post-Soviet republics. Especially Ukraine, Russia and Kazakhstan.

Countries such as Brazil, Canada, Australia, the USA, India and South Africa have large iron reserves. At the same time, almost every country on the globe has its own developed deposits, in case of a shortage of which, the breed is imported from other countries.

Enrichment of iron ores

As stated, there are several types of ores. The rich can be processed immediately after being extracted from the earth's crust, others must be enriched. In addition to the beneficiation process, ore processing includes several stages, such as sorting, crushing, separation and agglomeration.

To date, there are several main ways of enrichment:

Flushing.

It is used to clean ores from side impurities in the form of clay or sand, which are washed out using high-pressure water jets. This operation allows you to increase the amount of iron content in poor ore by about 5%. Therefore, it is used only in combination with other types of enrichment.

Gravity cleaning.

It is carried out using special types of suspensions, the density of which exceeds the density of the waste rock, but is inferior to the density of iron. Under the influence of gravitational forces, the side components rise to the top, and the iron sinks to the bottom of the suspension.

magnetic separation.

The most common enrichment method, which is based on a different level of perception by the ore components of the impact of magnetic forces. Such separation can be carried out with dry rock, wet rock, or in an alternate combination of its two states.

For the processing of dry and wet mixtures, special drums with electromagnets are used.

Flotation.

For this method, crushed ore in the form of dust is lowered into water with the addition of a special substance (flotation agent) and air. Under the action of the reagent, iron joins the air bubbles and rises to the surface of the water, and the waste rock sinks to the bottom. Components containing iron are collected from the surface in the form of foam.

In addition to the well-known oil and gas, there are other equally important minerals. These include ores that are mined for ferrous and by processing. The presence of ore deposits is the wealth of any country.

What are ores?

Each of the natural sciences answers this question in its own way. Mineralogy defines ore as a set of minerals, the study of which is necessary to improve the processes of extracting the most valuable of them, and chemistry studies the elemental composition of ore in order to identify the qualitative and quantitative content of valuable metals in it.

Geology considers the question: "what are ores?" from the point of view of the expediency of their industrial use, since this science studies the structure and processes occurring in the bowels of the planet, the conditions for the formation of rocks and minerals, and the exploration of new mineral deposits. They are areas on the surface of the Earth, on which, due to geological processes, a sufficient amount of mineral formations has accumulated for industrial use.

Ore formation

Thus, to the question: “what are ores?” The most complete answer is this. Ore is a rock with an industrial content of metals in it. Only in this case it has value. Metal ores are formed when the magma that contains their compounds cools. At the same time, they crystallize, distributing according to their atomic weight. The heaviest ones settle to the bottom of the magma and stand out in a separate layer. Other minerals form rocks, and the hydrothermal fluid left from the magma spreads through the voids. The elements contained in it, solidifying, form veins. Rocks, being destroyed under the influence of natural forces, are deposited at the bottom of reservoirs, forming sedimentary deposits. Depending on the composition of rocks, various ores of metals are formed.

Iron ores

The types of these minerals vary greatly. What are ores, in particular, iron? If the ore contains enough metal for industrial processing, it is called iron ore. They differ in origin, chemical composition, as well as the content of metals and impurities that may be useful. As a rule, these are associated non-ferrous metals, for example, chromium or nickel, but there are also harmful ones - sulfur or phosphorus.

The chemical composition is represented by its various oxides, hydroxides or carbonic salts of iron oxide. The developed ores include red, brown and magnetic iron ore, as well as iron luster - they are considered the richest and contain more than 50% metal. The poor include those in which the useful composition is less - 25%.

Composition of iron ore

Magnetic iron ore is iron oxide. It contains more than 70% pure metal, however, it occurs in deposits together with and sometimes with zinc blende and other formations. is considered the best of the used ores. Iron shine also contains up to 70% iron. Red iron ore - iron oxide - one of the sources of extraction of pure metal. And brown analogues have up to 60% metal content and are found with impurities, sometimes harmful. They are hydrous iron oxide and accompany almost all iron ores. They are also convenient for the ease of mining and processing, but the metal obtained from this type of ore is of low quality.

According to the origin of iron ore deposits, they are divided into three large groups.

Endogenous, or magmatogenic. Their formation is due to geochemical processes that took place in the depths of the earth's crust, magmatic phenomena.
Exogenous, or surface, deposits were created as a result of processes occurring in the near-surface zone of the earth's crust, that is, at the bottom of lakes, rivers, and oceans.
Metamorphogenic deposits were formed at a sufficient depth from the earth's surface under the influence of high pressure and the same temperatures.

Iron ore reserves in the country

Russia is rich in various deposits. The largest in the world is containing almost 50% of all world reserves. In this region, it was noted already in the 18th century, but the development of deposits began only in the 30s of the last century. The ore reserves in this basin are high in pure metal, they are measured in billions of tons, and mining is carried out by an open or underground method.

The Bakchar iron ore deposit, which is one of the largest in the country and the world, was discovered in the 60s of the last century. The ore reserves in it with a concentration of pure iron up to 60% are about 30 billion tons.

In the Krasnoyarsk Territory there is the Abagasskoye deposit - with magnetite ores. It was discovered back in the 30s of the last century, but its development began only half a century later. In the Northern and Southern zones of the basin, mining is carried out by open-pit mining, and the exact amount of reserves is 73 million tons.

Discovered in 1856, the Abakan iron ore deposit is still active. At first, the development was carried out in an open way, and since the 60s of the XX century - by an underground method at a depth of up to 400 meters. The content of pure metal in the ore reaches 48%.

Nickel ores

What is nickel ores? Mineral formations that are used for the industrial production of this metal are called nickel ores. There are sulfide copper-nickel ores with a pure metal content of up to four percent and silicate nickel ores, the same indicator of which is up to 2.9%. The first type of deposits is usually of the igneous type, and silicate ores are found in the weathering crust.

The development of the nickel industry in Russia is associated with the development of their location in the Middle Urals in the middle of the 19th century. Almost 85% of sulphide deposits are concentrated in the Norilsk region. The deposits in Taimyr are the largest and most unique in the world in terms of richness of reserves and variety of minerals; they contain 56 elements of the periodic table. In terms of the quality of nickel ores, Russia is not inferior to other countries, the advantage is that they contain additional rare elements.

About ten percent of nickel resources are concentrated in sulfide deposits on the Kola Peninsula, and silicate deposits are being developed in the Middle and Southern Urals.

The ores of Russia are characterized by the quantity and variety necessary for industrial applications. However, at the same time, they are distinguished by complex natural conditions of extraction, uneven distribution on the territory of the country, mismatch between the region where resources are located and the population density.

Man began to mine iron ore at the end of the 2nd millennium BC, having already determined for himself the advantages of iron over stone. Since that time, people began to distinguish between the types of iron ores, although they did not yet have the same names as today.

In nature, iron is one of the most common elements, and according to various sources, it is contained in the earth's crust from four to five percent. This is the fourth largest content after oxygen, silicon and aluminum.

Iron is not presented in its pure form, it is found in greater or lesser quantities in various types of rocks. And if, according to the calculations of specialists, it is expedient and economically profitable to extract iron from such a rock, it is called iron ore.

Over the past few centuries, during which steel and cast iron have been smelted very actively, iron ores have been depleted - after all, more and more metal is required. For example, if in the 18th century, at the dawn of the industrial era, ores could contain 65% iron, now the content of 15 percent of the element in the ore is considered normal.

What is iron ore made of?

The composition of the ore includes ore and ore-forming minerals, various impurities and waste rock. The ratio of these components differs from field to field.

The ore material contains the main mass of iron, and the waste rock is mineral deposits containing very little or no iron.

Iron oxides, silicates, and carbonates are the most common ore minerals in iron ores.

Types of iron ore by iron content and location.

Low iron or separated iron ore, below 20%
Medium iron or sinter ore
Iron-containing mass or pellets - rocks with a high iron content, above 55%

Iron ores can be linear - that is, occurring in places of faults and bends in the earth's crust. They are the richest in iron and contain little phosphorus and sulfur.

Another type of iron ores is flat-like, which is contained on the surface of iron-bearing quartzites.

Red, brown, yellow, black iron ore.

The most common type of ore is red iron ore, which is formed by anhydrous iron oxide hematite, which has the chemical formula Fe 2 O 3 . Hematite contains a very high percentage of iron (up to 70 percent) and few foreign impurities, in particular sulfur and phosphorus.

Red iron ore can be in a different physical state - from dense to dusty.

Brown iron ore is an aqueous iron oxide Fe 2 O 3 *nH 2 O. The number n may vary depending on the base that makes up the ore. Most often it is limonites. Brown iron ore, unlike red ones, contains less iron - 25-50 percent. Their structure is loose, porous, and there are many other elements in the ore, among which are phosphorus and manganese. Brown iron ore contains a lot of adsorbed moisture, while the waste rock is clayey. This type of ore got its name because of the characteristic brown or yellowish color.

But despite the rather low iron content, due to the easy reducibility, it is easy to process such ore. They are often used to produce high-quality cast iron.

Brown iron ore most often needs enrichment.

Magnetic ores are those formed by magnetite, which is a magnetic iron oxide Fe 3 O 4. The name suggests that these ores have magnetic properties that are lost when heated.

Magnetic ironstones are less common than red ones. But iron in them can contain even more than 70 percent.

In its structure, it can be dense and granular, it can look like crystals interspersed in the rock. The color of magnetite is black-blue.

Another type of ore, which is called spar iron ore. Its ore-bearing component is iron carbonate with the chemical composition FeCO 3 called siderite. Another name - clay iron ore - is if the ore contains a significant amount of clay.

Feldspar and clayey iron ore are less common in nature than other ores and contain relatively little iron and a lot of waste rock. Siderites can be transformed into brown iron ore under the influence of oxygen, moisture and precipitation. Therefore, the deposits look like this: in the upper layers it is brown iron ore, and in the lower layers it is spar iron ore.