Where to mine thorium in WWII 3.3 5. Copper ore is a natural raw material for copper mining

The question: where to find copper ore worries many geologists, but few people know that archaeologists can tell a lot of interesting things about this and their finds are sometimes more interesting than geological surveys. This is how Chelyabinsk summed up the results of archaeological research that was carried out in the Chelyabinsk region - Varensky district. A joint group of archaeologists took part in the research, which included representatives from Sheffield (Great Britain) and Pittsburgh (USA), as well as specialists - archaeological students from Chelyabinsk State Pedagogical University. These young archaeologists were conducting research on one of the most famous settlements in this area, dating back to the Bronze Age. This settlement is called “Ustye”. Other cultural monuments that belong to the Nizhny Toguzak river valley were also explored. Chelyabinsk State Pedagogical University I have been interested in this archaeological monument for quite some time.

It has been studied since 1984, and this process is constantly led by university professor Nikolai Vinogradov. During the excavations, a large settlement with powerful fortifications was discovered, in which one could find a large number of objects made of metal. As a survey of the settlement showed, approximately thirty metallurgical furnaces were located in 26 rooms found by researchers. This could only mean one thing, for local residents metal products were an integral part of their life. But until today it was not clear where the ore deposit was located, which was used for smelting. Also, no places were discovered where the primary melting of this metal took place. Main doctoroff.ru Medicine portal

To help their colleagues find the missing “puzzle pieces,” colleagues from Sheffield and Pittsburgh arrived at the excavation site, armed with the most modern tools that allow them to carry out the necessary research in geochemistry and geophysics. It was necessary to check chemical composition soils that make up the cultural layer in such a way as not to damage them, without subjecting them to destruction. Thanks to these modern devices, the expedition members still managed to discover copper mines, which were located at a short distance from the settlement - at a distance of 1-5 kilometers from the fortifications. According to researchers, these may be the remains of the very same mines where ore was mined. But there is no further evidence that these assumptions are true, so it cannot be assumed for sure that this is true, which means additional research will be required. This is what students and their leaders will do next year. There are already preliminary agreements to continue working together.

Copper ore is natural mineral, consisting of various chemical elements. Compositions that are profitable to process should include 0.5–1% of the main component. To others important element The ore is considered to be nickel.

Deposits on the world map

The largest ore reserves are located in Chile - 34% of the world's total. The USA and Peru each have 9% of fossil deposits. Eastern Siberia, the Urals and the Kola Peninsula account for 5% of the deposits.

The world's copper deposits are located in African continent, V South America, Canada, Australia. From European countries Poland is richest in them. There are known deposits in China and Mongolia.

Porphyry and vein deposits are located in the Western Pacific belt and Mediterranean regions. Kazakhstan, Armenia, and Uzbekistan have them.

Varieties of copper ores

Ore classification according to genetic and geological characteristics:

• stratiform - these are sandstones and shales;
• pyrite - vein copper and nuggets;
• hydrothermal - it is called the porphyry copper form;
• skarn rocks;
• igneous - this ore contains nickel;
• carbonate - have an iron-copper and carbonatite composition.

Natural minerals containing copper

Sulfide ore, its composition is determined by the expression Cu5FeS4. There are two polymorphic types - low-temperature and high-temperature. The melting point of which, respectively, is less than or greater than 228 degrees.

There is an early unstable sulfide, easily destroyed by water and wind. The other type is endogenous, and has a variable chemical composition due to admixtures of elements such as galena, pyrite, chalcocite, and chalcopyrite. Bornite is called variegated pyrite. The characteristics of these minerals depend on their origin.

The formula CuFeS2 determines its composition. Known as copper pyrite. Refers to polymetallic. It can exist in the form of skarns and mountain greisen.

Contains 79.8% copper and 20.2%. Very beautiful, the mirror surface has a grayish tint, sometimes black.

There are rare fossils containing copper elements:

• cuprite (Cu2O), an oxide, is seen among deposits of malachite and nuggets;
• covellite, contains 66.5% of the main element and sulfur. First found surrounded by the Vesuvius volcano. Mined in the USA, Greece, Chile;
• malachite. A stone that is used for various crafts. Polymetallic ore. Nizhny Tagil is the place of large deposits of this mineral;
• azurite This is azure, a blue stone. The main places of its production are Africa, Australia, England, and the Balkan countries. Occurs near sulfide deposits.

Porphyry copper forms include molybdenum, gold, chalcopyrite, and pyrite. They are found in deposits of poor people rocks. They have the form of veined stockwork-type inclusions.

Mineral extraction methods

Depending on the depth of occurrence, ore is mined using open or closed methods. There are standards that determine the feasibility of the depth of excavation of soil layers and the use of technologies that reduce their costs.

The work technology includes the following:

• use of self-propelled equipment;
• production of ore extraction directly;
• filling the resulting voids with materials to make further work safe.

When fossils are selected in layers, this ensures they are most full use. For deep quarries, the technology of cyclic-flow operations is suitable, it depends on the characteristics of the layers.

When layers occur at depths from 500 to 1000 m and deeper, it is convenient closed method copper mining This requires vibration mechanisms; the rock is completely excavated and delivered to the surface. The voids formed underground are filled using pipes lined with rubber or basalt resin.

It is economically advantageous to locate the mineral processing industry in close proximity to the places of their extraction. It is also necessary to build plants for recycling waste after processing. This may help highlight different healthy products. For example, processing sulfur dioxide makes it possible to obtain useful fertilizers containing sulfur.

Production technologies

The mined ore has a low concentration of copper. To obtain one ton of metal, on average, 200 tons of ore will be needed. To extract it, the modern metallurgical industry uses the following technologies:

• hydrometallurgical;
• pyrometallurgical;
• electrolysis.

The pyrometallurgical method of rock enrichment uses chalcopyrite for processing. This common technology uses two stages of operation. The first is oxidative roasting, the so-called flotation. The resulting rough concentrate contains 10–35% pure substance. Then the copper is refined and vitriol is added to the solution. As a result, they release almost one hundred percent purity.

With the hydrometallurgical method, the metal is leached, then sulfuric acid is added. As a result, a solution is obtained in which copper and various metals, which may be precious, are released. This technology is applicable for the production of copper from poor rocks.

For oxidative roasting of minerals with a high sulfur content, the ore is heated to 700–8000 degrees, and the amount of sulfur is halved. The result is an alloy of sulfides. Side airflow in the convector allows you to obtain blister copper of 91%. To achieve a higher purity of the metal, electrolytic refining occurs to obtain a 99% composition.

In industry, this element is practically not used in its pure form. The most famous alloys are:

• brass – an alloy with zinc;
• bronze – with tin;
• various babbits - an alloy with lead;
• cupronickel – nickel is added to the composition;
• duralumin – connection with aluminum;
• jewelry alloys, where gold is added in various percentages.

Areas of use

One area of ​​application is the electrical industry. Cables and electrical wires contain pure metal strands, which increases their electrical conductivity. Alloys with nickel are suitable for instrument making; compounds with tungsten are filaments in light bulbs.

Brass is used in the food and chemical industries. IN agriculture copper is used as fertilizer. Copper sulfate is known to gardeners; it is used to treat plants to protect them from diseases and pests.

In construction, such alloys are simply irreplaceable. The roof covering with the patina formed on it has beautiful view and very durable.

The medical industry cannot do without this chemical element. Widely used in medicines.

In mechanical engineering, bronze is used to make bearings, heat exchangers, and various structural elements of mechanisms. The metal is used in powder metallurgy to make friction parts.

World reserves

Copper is a non-ferrous metal that is consumed by many types of industries. The most profitable ore for production is bornite. This is due to its high content and large deposits in the world's subsoil. Rocks containing 0.5–1% of copper are suitable for copper mining. The most common are ores with nickel additives. They make up 90% of all copper-bearing minerals that are economically beneficial for the mining industry.

The largest copper deposits are located in Chile - 34% of all world reserves, which is 140 million tons.

The countries with the largest reserves in the world are: USA - 35 million tons, Indonesia - 35, Peru - 30, Australia - 24, China - 26, Russia - 20.

Global reserves of copper-bearing ores are estimated at 467 million tons. Geologists say that there are about 5 billion tons of deposits of such ore in the world's oceans.

The most common copper ore on our planet is bornite. But besides it, copper is also mined from other ores, which we will talk about in this article.

1

This ore refers to accumulations of minerals in which copper is present in such quantities that are considered suitable for processing for industrial purposes. A generally accepted indicator of the reasonableness of developing a deposit is considered to be a situation when copper accumulations in it are at least 0.5–1%.

Moreover, about 90% of the reserves of this metal on earth are found in ores containing not only copper, but also other metals (for example, nickel).

Large-scale copper mining in Russia is carried out in Eastern Siberia, in the Urals and the Kola Peninsula. The largest deposits of this metal are present in Chile (according to experts, about 190 million tons). Other countries engaged in the development of such ores include the USA, Zambia, Kazakhstan, Poland, Canada, Zaire, Armenia, Congo, Peru, and Uzbekistan. In total, the planet's total reserves of copper in explored deposits are approximately 680 million tons.

All copper deposits are usually divided into six genetic groups and nine industrial geological types:

• stratiform group (copper shales and sandstones);
• pyrite (native copper, vein and copper-pyrite type);
• hydrothermal (porphyry copper ores);
• igneous (copper-nickel ore);
• skarn;
• carbonate (iron-copper and carbonatite type).

In our country, the main extraction of copper is carried out on cuprous shales and sandstones, from copper pyrites, copper-nickel and porphyry copper ores.

2

In nature, copper is quite rare in its native form. Most often, it “hides” in various connections. The most famous of them are the following:

3

Other copper minerals are much less common, among which are the following:

4

This metal, whose characteristics (for example, high ) have led to its wide demand) is obtained from the minerals and ores described by us in three ways - hydrometallurgical, pyrometallurgical and electrolysis. The most common is pyrometallurgical technology, which uses the mineral chalcopyrite as a feedstock. General scheme The pyrometallurgical process includes several operations. The first of them is the enrichment of copper ore by oxidative roasting or flotation.

The flotation method is based on the difference in wettable gangue and copper-containing particles. Due to this, some mineral elements adhere (selectively) to the air bubbles and are transported to the surface by them. This simple technology makes it possible to obtain a powdered concentrate, in which the copper content varies from 10 to 35 percent.

Oxidative roasting (not to be confused with) is more often used when the initial raw material contains sulfur in large quantities. In this case, the ore is heated to a temperature of 700–800 degrees, which leads to the oxidation of sulfides and a halving of the sulfur content. After this, smelting is performed for matte (an alloy with iron and copper sulfides, produced in reverberatory or shaft furnaces) at a temperature of 1450 degrees.

The copper matte, which is obtained after all these operations, is blown in horizontal converters without supplying additional fuel ( chemical reactions provide the heat necessary for the process) with side blast for the oxidation of iron and sulfides. The resulting sulfur is converted into SO2, and the oxides into slag.

As a result, what comes out of the converter is so-called black copper, in which the metal content is approximately 91%. Subsequently, it is purified using fire refining (removing unnecessary impurities) and an acidified solution of copper sulfate (copper). This cleaning is called electrolytic, after which the copper content reaches 99.9%.

In the hydrometallurgical method of copper production, it is obtained by leaching the metal with sulfuric acid (a very weak solution) and isolating copper and other copper from the resulting solution. precious metals. This technique is recommended for working with low-grade ores.

Copper, actively used in almost all industries, is mined from various ores, the most common of which is bornite. The popularity of this copper ore is explained not only by the high copper content in its composition, but also by significant reserves of bornite in the bowels of our planet.

Copper ore deposits

Copper ores- this is an accumulation of minerals, which, in addition to copper, also contain other elements that form their properties, in particular nickel. The copper ore category includes those types of ores that contain such an amount of this metal that it is economically feasible to extract it by industrial methods. These conditions are satisfied by ores whose copper content is in the range of 0.5–1%. Our planet has a reserve of copper-containing resources, the bulk of which (90%) are copper-nickel ores.

Most of the copper ore reserves in Russia are located in Eastern Siberia, on the Kola Peninsula, in the Ural region. Chile is on the list of leaders in total reserves of such ores; deposits are also being developed in the following countries: the USA (porphyry ores), Kazakhstan, Zambia, Poland, Canada, Armenia, Zaire, Peru (porphyry ores), Congo, Uzbekistan. Experts have calculated that large copper deposits in all countries contain a total of about 680 million tons. Naturally, the question of how copper is mined in different countries must be considered separately.

All copper ore deposits are divided into several categories, differing in genetic and industrial-geological characteristics:

• stratiform group represented by copper shales and sandstones;
• pyrite ores, which include native and vein copper;
• hydrothermal, including ores called porphyry copper;
• igneous, which are represented by the most common ores of the copper-nickel type;
• skarn type ores;
• carbonate, represented by ores of the iron-copper and carbonatite type.

In Russia, it is carried out mainly in shale and sand deposits, in which the ore is contained in copper pyrite, copper-nickel and porphyry copper forms.

Natural compounds containing copper

Pure copper, which is what its nuggets represent, is found in nature in very small quantities. Copper is mainly found in nature in the form of various compounds, the most common of which are the following.

• Bornite is a mineral that got its name in honor of the Czech scientist I. Born. This is a sulfide ore, the chemical composition of which is characterized by its formula - Cu5FeS4. Bornite has other names: variegated pyrite, copper purple. In nature, this ore is presented in two polymorphic forms: low-temperature tetragonal-scalenohedral (temperature less than 228 degrees) and high-temperature cubic-hexaoctahedral (more than 228 degrees). This mineral can have different types depending on its origin. Thus, exogenous bornite is a secondary early sulfide, which is very unstable and is easily destroyed by weathering. The second type, endogenous bornite, is characterized by variable chemical composition, which may contain chalcocite, galena, sphalerite, pyrite and chalcopyrite. Theoretically, minerals of these types can contain from 25.5% sulfur, more than 11.2% iron and over 63.3% copper, but in practice this content of these elements is never maintained.
• Chalcopyrite is a mineral whose chemical composition is characterized by the formula CuFeS2. Chalcopyrite, which is of hydrothermal origin, was previously called copper pyrite. Along with sphalerite and galena, it is included in the category of polymetallic ores. This mineral, which, in addition to copper, contains iron and sulfur, is formed as a result of metamorphic processes and can be present in two types of copper ores: contact-metasomatic type (skarns) and mountain metasomatic (greisens).
• Chalcocite is a sulfide ore, the chemical composition of which is characterized by the formula Cu2S. This ore contains a significant amount of copper (79.8%) and sulfur (20.2%). This ore is often referred to as “copper lustre”, due to the fact that its surface appears as a shiny metal, ranging in shades from lead-gray to completely black. In copper-bearing ores, chalcocite appears as dense or fine-grained inclusions.

In nature, there are also rarer minerals that contain copper.

• Cuprite (Cu2O), a member of the oxide group of minerals, can often be found in places where there is malachite and native copper.
• Covelline is a sulfide rock formed metasomatically. This mineral, whose copper content is 66.5%, was first discovered at the beginning of the last century in the vicinity of Vesuvius. Now covellite is actively mined in deposits in countries such as the USA, Serbia, Italy, and Chile.
• Malachite is a mineral well known to everyone as an ornamental stone. Surely everyone has seen products made from this beautiful mineral in the photo or even owns them. Malachite, which is very popular in Russia, is copper carbonate or copper dihydrocoxcarbonate, which belongs to the category of polymetallic copper-containing ores. The malachite found indicates that there are deposits of other minerals containing copper nearby. In our country, a large deposit of this mineral is located in the Nizhny Tagil region; previously it was mined in the Urals, but now its reserves there are significantly depleted and are not being developed.
• Azurite is a mineral that is also called “copper blue” due to its blue color. It is characterized by a hardness of 3.5–4 units; its main deposits are developed in Morocco, Namibia, Congo, England, Australia, France and Greece. Azurite is often intergrown with malachite and occurs in places where deposits of sulfide-type copper-bearing ores are located nearby.

Copper production technologies

To extract copper from the minerals and ores we discussed above, modern industry uses three technologies: hydrometallurgical, pyrometallurgical and electrolysis. The pyrometallurgical method of copper enrichment, which is the most common, uses chalcopyrite as a raw material. This technology involves performing several sequential operations. At the first stage, copper ore is enriched, for which oxidative roasting or flotation is used.

The flotation method is based on the fact that the gangue and its parts containing copper are wetted differently. When the entire mass of rock is placed in a bath with a liquid composition in which air bubbles are formed, the part that contains mineral elements is transported by these bubbles to the surface, adhering to them. As a result, a concentrate is collected on the surface of the bath - blister copper, which contains from 10 to 35% of this metal. It is from such a powdery concentrate that what follows occurs.

Oxidative roasting, which is used to enrich copper ores containing a significant amount of sulfur, looks somewhat different. This technology involves heating the ore to a temperature of 700–8000, as a result of which sulfides are oxidized and the sulfur content in copper ore decreases almost twofold. After such roasting, the enriched ore is melted in reverberatory or shaft furnaces at a temperature of 14500, resulting in matte - an alloy consisting of copper and iron sulfides.

In the bowels of the earth there are quite a large number of different minerals that can be used to release various materials. Enough widespread has copper ore - it is used for processing and producing various substances that are used in industry. It is worth considering that such ore, which contains copper, may also contain other minerals. It is recommended to use earthen rock that contains at least 0.5-1% metal.

Classification

A huge amount of a wide variety of copper ores are being mined. The classification is carried out according to their origin. The following groups of copper ores are distinguished:

1. Pyrite has become quite widespread. The rock is a compound of iron and copper and has a large number of various inclusions and veins of other impurities.
2. Stratiform is represented by a combination of copper shales and sandstones. This kind of breed has also become widespread, as it is represented large deposit. The main characteristics include a simple sheet shape, as well as a uniform distribution of all useful components. Due to this, copper rock of this type is most in demand, as it allows for productivity at the same level.
3. Copper-nickel. This ore is characterized by massive texture inclusions of cobalt and gold, as well as platinum group metals. The deposits are in vein and sheet form.
4. Porphyry copper or hydrothermal. Copper ore deposits of this kind contain a large concentration of silver and gold, selenium and other chemical substances. In addition, all useful substances are in higher concentration, due to which the breed is in demand. It is extremely rare.
5. Carbonate. This group includes iron-copper and carbonatite ore. It is worth considering that this breed was found only in South Africa. The mine being developed is classified as massive alkaline rock.
6. Skarn is a group that is characterized by a local location in a wide variety of rocks. Characteristic properties can be called small sizes and complex morphology. It is worth considering that in this case the ore containing copper has a high concentration. However, the metal is unevenly distributed. The rocks being mined have a copper concentration of about three percent.

Copper practically does not occur, for example, like gold, in the form of massive nuggets. The largest similar education can be called a deposit in North America, whose mass is 420 tons. With 250 types of copper, only 20 of them are widely used in their pure form, others are used only as alloying elements.

Copper ore deposits

Copper is considered the most common metal, which is used in a wide variety of industries. Deposits of copper ore are found in almost all countries. An example is the discovery of deposits in Arizona and Nevada. Copper ore is also mined in Cuba, where oxide deposits are common. In Peru, chloride formations are being mined.

The use of the mined copper mixture is associated with the production of various metals. There are two main copper production technologies:

1. hydrometallurgical;
2. pyrometallurgical.

The second method involves fire refining of metal. Due to this, ore can be processed in almost any volume. In addition, exposure to fire allows almost all useful substances to be extracted from the rock. Pyrometallurgical technology is used to isolate copper from rocks that have a low degree of metal enrichment. The hydrometallurgical method is used exclusively for processing oxidized and native rock, which also have low copper concentrations.

In conclusion, we note that copper today is included in almost all alloys. Its addition as an alloying element allows you to change the basic performance properties.