Technology of production and mining of copper. What is copper ore, how it is mined, processed and what it is used for Getting copper from ore at home

Copper in the world industry occupies one of the key positions. Due to its high thermal and electrical conductivity, it is widely used in electrical engineering, and its high mechanical strength and suitability for machining makes it indispensable in pipe production for internal systems.

Copper mining in Russia brings very fruitful results. And the fact that 40% of Russia's raw material base consists of copper-nickel sulfide deposits, and 19% of pyrites gives Russia a considerable advantage over other countries.

The value of copper in the world

Features of copper

Copper was one of the first metals to be recognized and used by human civilization. Man invented its production earlier than iron.

Copper is the second most consumed non-ferrous metal after aluminum.

This metal got its name from the name of the island of Cyprus.

What does it consist of? There are many crystals in its structure: nickel, zinc, molybdenum, gold, calcium, silver, lead, iron, cobalt and many others.

And its high electrical conductivity has made it a particularly valuable electrical material, from which the windings of transformers and generators, wires of power lines, and internal electrical wiring are made.

Reference. Previously, up to half of all copper produced in the world was spent on electrical wire, but today more affordable aluminum serves these purposes. And copper itself becomes the most scarce non-ferrous metal.

Copper alloys are also widely used - with zinc (brass), with tin or aluminum (bronze), etc.

Mining

Copper ores are mined in 50 countries.

The main production capacities of copper mining enterprises are concentrated in South America. It is here that 41.2% of the world's copper ore is mined, 19.8% falls on the share of Asian countries.

The situation in the production of refined copper looks different:

Source: site people.conomy.ru

The production of refined copper in 2015 is concentrated in the Asian region (51.2%). South America, the leader in copper ore mining, accounts for 14.9%. Here it is inferior even to Europe.

Almost 80% of all copper was produced from primary raw materials, the remaining 20% ​​was produced from copper scrap. High consolidation remains in global copper production - a third of it (34.8%) in 2015 was accounted for by the five largest producers, which include:

• Codelco (Chile).
• Freeport-McMoRan (USA).
• Glencore (Switzerland).
• BHP Billiton (Australia).
• Southern Copper (Mexico).

For reference. Wood Mackenzie (Brook Hunt) in 2014 published a forecast of copper production in the world for the period up to 2025.

Wood Mackenzie is a global energy, chemicals, renewables, metals and mining research group with an international reputation for providing comprehensive data, written analysis and advice. In 2015, the company was acquired by American analytics company and analytics company Verisk Analytics (en.wikipedia.org).

Source: Wood Mackenzie (Brook Hunt)

According to the company, global production in 2016 amounted to 19.9 million tons, and its production reached 22.5 million tons.

Stocks

According to 2014 data, the Americas held almost 60% of the world's reserves, more than half of which were recorded in Chile. And on a global scale, this country accounts for 34% of the deposits of this non-ferrous metal.

Rice. 2. Copper deposits in the world 2014
Source: site mining-prom.ru

The share of the Russian Federation accounted for 5% of the explored copper reserves in the world (after Chile, the USA, Peru and Australia, this is the 5th place).

According to geologists, about 5 billion tons of copper ore reserves are at the bottom of the oceans.

Copper industry in Russia

In the Urals and in Western Siberia, no, no, yes, and they find the oldest mines from the Stone Age. Our forefathers worked in them, extracting copper ores among other minerals for the invaders.

Although, according to official sources, non-ferrous metals were practically not mined in Rus' until the 18th century.

Non-ferrous metallurgy of the Russian Empire

The experience of the first state copper smelters, which appeared in the period 1638-1640, when copper deposits were discovered on the river. Kalkarke, was unsuccessful. There was not enough ore to provide loading. Less than ten years later, production had to be stopped, and the factories themselves closed.

Peter's reforms gave a new impetus to the development of the mining industry - he transferred the exploration and processing of non-ferrous metal ores to private hands. The Berg Collegium, created by the emperor, served as a kind of Ministry of Geology (if we draw analogies), deciding who should be given the authority to search for and develop ores, and who should not.

Moreover, there was no need to talk about “rich deposits”. There were small sources in the Olonets province and Pechora, but they were clearly lacking for the needs of the domestic market. So the main supplier of non-ferrous metal for the Russian Empire was Europe. And the military-strategic position of Rus' required as much iron and copper as possible. They were called the metals of war. Developments in the Urals were supposed to correct the situation.

In 1750, 72 "iron" and 29 copper smelters in Russia produced finished products. But by the 1990s, two enterprises of the Bogoslovsky and Votsky districts represented the entire Ural production.

“On the western slope of the Urals, which was once covered by a whole series of copper smelters, only one Yugovsky plant continues to operate with a capacity of only about 40 tons of copper. Along the entire eastern slope of the Urals, from the north of the Bogoslovsky plants up to the Preobrazhensky plant in the south of the Urals, there are scattered copper smelters and mines that once operated, a large suit of which has not been developed for several decades ”(L. B. Kafengauz“ Evolution of industrial production in Russia ").

Rice. 3. View of the Miass copper smelter in the Urals. 1773
Source: website infourok.ru

And only at the end of the 90s a shift in the development of the copper business is planned - a shift that turned into an upswing only at the beginning of the 20th century, turning the copper industry into one of the rapidly developing industries. Since 1906, a truly fantastic growth in copper production began, and in 7 years it increased by 3.6 times.

And even the decline, when the country was going through hard times, revolutions and wars, and it lasted no less than 15 years, did not prevent Soviet Russia from achieving considerable success in the copper industry.

The present day of the copper industry of the Russian Federation

Russia has been a major supplier of copper and copper products to the world market for many years. In 2016, 860.1 thousand tons of refined copper were produced here. Copper mining amounted to 844.7 thousand tons.

Rice. 4. Open pit copper mining at Gaisky GOK UMMC
Source: website

Copper production centers

The location of enterprises in the industry is influenced by certain factors:

• raw materials;
• energy and fuel;
• consumers.

There are not so many metals on our planet whose production volumes exceed those of copper. The twenty-ninth number in the periodic table of Mendeleev is in an honorable third place in terms of production levels, immediately after iron and aluminum. Too many industries wouldn't be in trouble if they ran out of much-needed metal in their pantries. The importance of copper and copper ore can hardly be overestimated for electrical engineering, heat engineering, metallurgy, medicine and even transport.

What is copper ore

Copper ore, like any other, is a conglomerate of substances, rocks, minerals, the content of the desired substance in which is so high that it is considered appropriate for mining. It is worth saying that, along with the so-called Cuprum (the Latin name for copper), other useful elements are also mined in its ore in even smaller proportions. Copper itself begins to be mined in ores, in which its amount exceeds 0.5%.

Yes, in its pure form, copper is found in nature even more often than the same aluminum, but still, this figure is about one percent of the world's reserves, because mining is still carried out from ores. The following groups of ores are distinguished according to the places of formation and composition: carbonate, pyrite, copper-nickel, copper-porphyry (hydrothermal), skarn, stratiform.

Saturation Differences

There are a lot of variations of copper compounds with other substances in ores, about two and a half hundred. We will consider the most popular and most saturated:

1. Bornite. Most often it belongs to the hydrothermal group of ores, it can contain about 65% Cuprum in its composition. Chem. formula - Cu 5 FeS 4;
2. Kovelin. Also a member of the hydrothermal group, up to 64% copper. Formula - CuS;
3. Chalcopyrite. hydrothermal group. Copper saturation is 30%. The most popular ore is 50% of all deposits. Formula - CuFeS 2;
4. Halkozin. The leader in terms of saturation. 79.8% red metal. All the same hydrothermal group. Formula - Cu 2 S.

Methods for extracting copper ore

There are two methods of mining - mine and open. That's all that modern technology can boast of during the extraction of ores. The open method is used in cases where the copper deposit is not located very deep underground (about 400-500 meters). To begin with, a layer of waste rock is removed, and then the mining process itself begins, to facilitate which directed explosions are used.

In the case of the mine method, as the name implies, they break through the mine. The depth sometimes reaches a kilometer. The mines are equipped with elevators for transporting equipment and workers, as well as for transporting the resulting ore to the top. Studded drilling machines, biting into the rock, extract the ore necessary for production from the mines.

Processing of obtained ore

As of today, there are 3 ways to process the resulting copper ore. Pyrometallurgical, hydrometallurgical and electrolysis.

The pyrometallurgical method is the most popular. The most common chalcopyrite is taken as the "working material".

At the very beginning, enrichment is performed. For this, the oxidative firing method is used. This method is very suitable for chalcopyrite, as it is primarily designed for ores with a high sulfur concentration. With this technology, the ore is heated to high temperatures (sometimes up to 8 thousand degrees Celsius), during which sulfur and oxygen interact, after which almost half of the sulfur evaporates. Further, the ore is heated even more in shaft or reverberatory furnaces. We are already talking about 1.4-1.5 thousand degrees.

Sometimes copper, as a material similar in color, is used to make fake jewelry. In order to avoid fakes, be aware that copper darkens over time, and a metallic smell remains in the water after it.

At the output, after exposure to such temperatures, an alloy of copper and iron sulfides is obtained - matte. The alloy is blown by convectors, due to which both iron and sulfur are once again oxidized, escaping somewhere, and somewhere - settling as slag. The product becomes 91% blister copper.

In order to achieve almost the standard copper content in the alloy, fire refining technology is used. An acidified solution of CuSO 4 is also used with it. After these manipulations, which, by the way, are called the electrolytic refining of copper, we get "in our hands" actually "purebred" copper, with a concentration of 99.9%.

Copper mining in the world

Chile holds the first place both in terms of copper reserves and its production on planet Earth. A third of the world's reserves are concentrated here. Copper has been mined in the Chuquicamata deposit for over 100 years. During this time, more than 26 million tons were mined. The second and third places are taken by America and China. In terms of the amount of copper ore in Russia, the country ranks fifth in the world along with Poland and Indonesia. Each country contains 4% of the world's reserves of this mineral.

Copper and copper ore in Russia

In Russia, copper ore reserves can be noted in the Norilsk, Oktyabrskoye, Tapakhninskoye deposits. They contain about 60% of all copper reserves in the country. The recently discovered Udokan mine (Chita region) can provide the country with ore for about 30 years. But so far, no work has been carried out at this place, since it is located in a place with a rudimentary transport interchange.

The use of copper

It is easier to indicate areas where copper is not used than to cover all areas of its use. Indeed, even in the human body there is a need for a daily dose of copper (about 0.9 mg per day).

Due to its low resistivity, Cuprum is used for the production of wires, cables, electric coils, transformers and other electrical equipment.

Due to the high thermal conductivity, in turn, copper is involved in the design of elements of cooling, heating, and air conditioning systems.

In one area of ​​transportation, namely pipelines, seamless copper pipes have become an ideal container for transporting both water and gas through them.

Jewelers use an alloy of gold and copper to strengthen the former. Since gold, in itself, is a very soft metal, and products without an admixture of copper would be extremely susceptible to deformation.

In connection with the identification of the bactericidal properties of copper, in the future it has a chance to be widely used in medicine, both for the manufacture of tools and work surfaces, and for the material for ordinary door handles.

Copper today is an unusually demanded metal and is widely used both in everyday life and in industry. In nature, Cu can be found both in a pure state and in the form of an ore. There are several ways to extract and obtain copper from the original rocks. However, they are widely used in industry. How copper is mined will be discussed in the article.

A bit of history

In what area copper in ancient times began to be mined and used by man for the first time, archaeologists, unfortunately, could not find out. However, it is known for certain that it was this metal that people began to process and use in everyday life the very first.

Copper has been known to man since the Stone Age. Some nuggets of this metal found by archaeologists bear traces of processing with stone axes. Initially, people used copper mainly as decorations. At the same time, people in ancient times used exclusively the nuggets of this metal found by them for the manufacture of such products. Later, people learned to process copper-containing ore.

Many peoples of antiquity had an idea of ​​how Cu was mined and processed. A lot of evidence has been found by archaeologists. After man learned to make alloys of copper and zinc, the Bronze Age began. Actually, the name "copper" was once coined by the ancient Romans. Such metal was brought to this country mainly from the island of Cyprus. That is why the Romans called it aes cyprium.

Since this metal was once used very widely in everyday life by man, the technologies for its extraction were, of course, developed quite advanced. Our ancestors obtained copper mainly from malachite ores. A mixture of such material and coal was placed in an earthen vessel and placed in a pit. Next, the mass in the pot was set on fire. The resulting carbon monoxide reduced malachite to copper.

stocks in nature

Where can copper be found in the wild today? At the moment, deposits of this popular metal are discovered on all continents of the Earth. At the same time, Cu reserves are considered practically unlimited. Geologists in our time are finding new deposits of pure copper, as well as ores containing it. For example, in 1950 the world reserves of this metal amounted to 90 million tons. By 1970, this figure had already increased to 250 million tons, and by 1998 - up to 340 million tons. At the moment, it is believed that copper reserves on the planet are more than 2.3 billion tons.

Deposits and methods of extraction of pure copper

As already mentioned, initially people used native Cu in everyday life. Of course, such pure copper is mined today. Nuggets of this metal are formed in the earth's crust as a result of exogenous and endogenous processes. The largest known deposit of native copper on the planet is currently located in the United States, in the Lake Superior region. In Russia, native copper occurs in the Udokan deposit, as well as in some other places in Transbaikalia. In addition, the answer to the question of where copper can be mined in Russia in the form of nuggets is the Ural region.

In nature, pure metal of this variety is formed in the zone of oxidation of copper sulfate deposits. Usually, nuggets of copper itself contain about 90-99%. The rest is accounted for by other metals. In any case, two main technologies serve as an answer to the question of how native copper is mined. Such deposits, as well as ore ones, are developed by a closed mine or open pit method. In the first case, such technological processes as drilling and breaking are used.

Copper nuggets can weigh a lot. The largest of them were once found on Lake Superior in the USA. The weight of these nuggets was about 500 tons.

Where copper is mined in Russia, we found out. This is mainly Transbaikalia and the Urals. In our country, of course, very large nuggets of this metal were also found at different times. For example, copper pieces weighing up to several tons were often found in the Middle Urals. One of these nuggets weighing 860 kg is now kept in St. Petersburg, in the Museum of the Mining Institute.

Copper ores and their deposits

At present, obtaining Cu is considered economically viable and expedient even if it is contained in the rock at least 0.3%.

Most often, for the extraction of copper by an industrial method in nature, the following rocks are mined today:

bornites Cu 5 FeS 4 - sulfide ores, otherwise called copper purple or variegated pyrites and containing about 63.3% Cu;

chalcopyrite CuFeS 2 - minerals of hydrothermal origin;

chalcosines Cu 2 S containing more than 75% copper;

cuprites Cu 2 O, often also found in places of deposits of native copper;

malachites, which are carbonic copper greens.

The largest deposit of copper ores in Russia is located in Norilsk. Also, such rocks are mined in large quantities in some places in the Urals, in Transbaikalia, in Chukotka, in Tuva and on the Kola Peninsula.

How copper ore deposits are mined

Various kinds of rocks containing Cu, as well as nuggets, can be mined on the planet using two main technologies:

closed;

open.

In the first case, mines are built at the deposit, the length of which can reach several kilometers. To move workers and equipment, such underground tunnels are equipped with elevators and railway tracks. Rock crushing in mines is carried out using special drilling equipment with spikes. The intake of copper ore and its loading for shipment to the top are carried out using buckets.

If the deposits are located no further than 400-500 m from the surface of the earth, their extraction is carried out by an open method. In this case, the upper rock layer is first removed from the field using explosive devices. Further, the copper ore itself is gradually removed.

Methods for obtaining metal from rocks

How copper is mined, or rather, ores containing it, we have thus found out. But how can Cu itself be obtained at enterprises subsequently?

There are three main ways to extract copper from rocks:

electrolytic;

pyrometallurgical;

hydrometallurgical.

Pyrometallurgical flotation method

This technology is commonly used to isolate copper from rocks containing 1.5-2% Cu. Such material is enriched by the flotation method. Wherein:

the ore is carefully ground to the finest powder;

mixing the resulting material with water;

special flotation reagents, which are complex organic substances, are added to the mass.

Flotation reagents cover small grains of various copper compounds and impart non-wettability to them.

At the next stage:

substances that create foam are added to the water;

passing a strong stream of air through the suspension.

As a result, light dry particles of copper compounds stick to air bubbles and float to the top. The foam containing them is collected, squeezed out of water and dried thoroughly. As a result, a concentrate is obtained, from which crude Cu is then isolated.

How copper is mined from ore: beneficiation by roasting

The flotation method is used quite often in industry. But sometimes roasting technology is also used to enrich copper ore. This technique is most often used for ores containing a large amount of sulfur. In this case, the material is preheated to a temperature of 700-8000 °C. As a result, sulfides are oxidized with a decrease in the sulfur content in the rock.

At the next stage, the ore prepared in this way is melted in shaft furnaces at a temperature of 14500 ° C. Ultimately, when using this technology, a matte is obtained - an alloy of copper and iron. Further, this connection is improved by blowing in converters. As a result, iron oxide passes into slag, and sulfur into SO4.

Obtaining pure copper: electrolysis

When using flotation and roasting methods, blister copper is obtained. Actually, such a material contains about 91% Cu. To obtain purer copper, rough copper is further refined.

In this case, thick anode plates are first cast from primary copper. Further:

collect a solution of copper sulfate in the bath;

hang anode plates in the bathroom;

thin sheets of pure copper are used as cathodes.

During the electrolysis reaction, copper is dissolved at the anodes and precipitated at the cathodes. Copper ions move towards the cathode, take electrons from it and pass into Cu+2+2e?>Cu atoms.

Copper sulfate is obtained by slow oxidation of sulfide ore with oxygen to copper sulfate CuS + 2O 2 > CuSO 4. The salt is then leached out with water.

Hydrometallurgical method

In this case, sulfuric acid is used to leach and enrich copper. As a result of the reaction using this technology, a solution saturated with Cu and other metals is obtained. Copper is then isolated from it. Using this technique, in addition to blister copper, other metals, including precious ones, can be obtained. In any case, this technology is most often used to isolate Cu from rocks that are not too rich in Cu (less than 0.5%).

Copper at home

The separation of this metal from ores saturated with it is, therefore, a relatively simple process technologically. Some therefore are interested in how to mine copper at home. However, it will be very difficult to obtain this metal from ore, clay, etc. with your own hands, without special equipment.

Some, for example, are interested in how to extract copper from clay with their own hands. Indeed, in nature there are deposits of this material, which is also rich in Cu. However, unfortunately, there are no known proven technologies for obtaining copper from clay at home.

With your own hands, you can try to isolate this metal at home, perhaps only from copper sulfate. To do this, the latter must first be dissolved in water. Next, you just need to place some iron object in the resulting mixture. After some time, the latter - as a result of a substitution reaction - will be covered with a copper coating, which can then simply be cleaned off.