uranium ore. Uranium deposits in the world

Discovery on a planetary scale. So you can call the discovery by scientists of Uranus. The planet was discovered in 1781.

Her discovery was the reason for naming one of elements of the periodic table. Uranus metal was isolated from resin blende in 1789.

The hype around the new planet has not yet subsided, therefore, the idea of ​​​​naming a new substance lay on the surface.

At the end of the 18th century there was still no concept of radioactivity. Meanwhile, this is the main property of terrestrial uranium.

Scientists who worked with him were irradiated without knowing it. Who was the pioneer, and what are the other properties of the element, we will tell further.

Properties of uranium

Uranium is an element discovered by Martin Klaproth. He fused the resin with the caustic. The fusion product was not completely soluble.

Klaproth realized that there were no supposed, and in the composition of the mineral. Then, the scientist dissolved the snag in.

Green hexagons fell out of the solution. The chemist exposed them to yellow blood, that is, potassium hexacyanoferrate.

A brown precipitate fell out of the solution. Klaproth reduced this oxide with linseed oil and calcined it. Got a powder.

I had to ignite it already, mixing it with brown. Grains of a new metal were found in the sintered mass.

Later it turned out that it was not pure uranium, and its dioxide. Separately, the element was received only 60 years later, in 1841. And after another 55, Antoine Becquerel discovered the phenomenon of radioactivity.

Radioactivity of uranium due to the ability of the nucleus of an element to capture neutrons and break up. At the same time, impressive energy is released.

It is due to the kinetic data of radiation and fragments. It is possible to ensure the continuous fission of nuclei.

The chain reaction starts when natural uranium is enriched with its 235th isotope. It is not something that is added to the metal.

On the contrary, the low-radioactive and inefficient 238th nuclide, as well as the 234th, are removed from the ore.

Their mixture is called depleted, and the remaining uranium is called enriched. This is exactly what industrialists need. But, we will talk about this in a separate chapter.

Uranus radiates, both alpha and beta with gamma rays. They were discovered by seeing the effect of the metal on a photographic plate wrapped in black.

It became clear that the new element was emitting something. While the Curies were investigating what it was, Marie received a dose of radiation that caused the chemist to develop blood cancer, from which the woman died in 1934.

Beta radiation can destroy not only the human body, but also the metal itself. What element is formed from uranium? Answer: Brevi.

Otherwise, it is called protactinium. Discovered in 1913, just when studying uranium.

The latter turns into brevia without external influences and reagents, only from beta decay.

Externally uranium is a chemical element- colors with a metallic sheen.

This is how all actinides look, to which the 92nd substance belongs. The group starts with the 90th number, and ends with the 103rd.

Standing at the top of the list radioactive element uranium, acts as an oxidizing agent. The oxidation states can be 2nd, 3rd, 4th, 5th, 6th.

That is, chemically the 92nd metal is active. If you grind uranium into a powder, it will ignite spontaneously in air.

In its usual form, the substance will oxidize upon contact with oxygen, becoming covered with an iridescent film.

If the temperature is raised to 1000 degrees Celsius, chem. element uranium connect with . Metal nitride is formed. This substance is yellow.

Throw it into water and dissolve like pure uranium. Corrode it and all acids. The element displaces hydrogen from organic matter.

Uranium pushes it out, in the same way, from salt solutions,,,,,. If such a solution is shaken, the particles of the 92nd metal will begin to glow.

uranium salts unstable, decompose in the light, or in the presence of organics.

The element is indifferent, perhaps, only to alkalis. The metal does not react with them.

Discovery of uranium is the discovery of a superheavy element. Its mass makes it possible to isolate the metal, more precisely, the minerals with it, from the ore.

It is enough to crush it and fall asleep in water. The uranium particles will settle first. This is where mining starts. Details in the next chapter.

Uranium mining

Having received a heavy sediment, industrialists leach the concentrate. The goal is to bring the uranium into solution. Sulfuric acid is used.

An exception is made for tar. This mineral is insoluble in acid, therefore, alkalis are used. The secret of difficulties in the 4-valence state of uranium.

Acid leaching does not pass with , . In these minerals, the 92nd metal is also 4-valent.

This is treated with hydroxide, known as sodium hydroxide. In other cases, oxygen purge is good. No need to separately stock up on sulfuric acid.

It is enough to heat the ore with sulfide minerals up to 150 degrees and send an oxygen jet to it. This leads to the formation of an acid that leaches Uranus.

Chemical element and its application associated with pure forms of metal. Sorption is used to remove impurities.

It is carried out on ion exchange resins. Also suitable for extraction with organic solvents.

It remains to add alkali to the solution in order to precipitate ammonium uranates, dissolve them in nitric acid and subject them to.

The result will be the oxides of the 92nd element. They are heated to 800 degrees and reduced with hydrogen.

The resulting oxide is converted to uranium fluoride, from which the pure metal is obtained by calcium thermal reduction. , as you can see, is not simple. Why try so hard?

Application of uranium

The 92nd metal is the main fuel for nuclear reactors. A lean mixture is suitable for stationary, and an enriched element is used for power plants.

The 235th isotope is also the basis of nuclear weapons. Secondary nuclear fuel can also be obtained from the 92nd metal.

Here it is worth asking the question, what element turns uranium. From its 238th isotope, one more radioactive, superheavy substance is obtained.

At the very 238th uranium great half life, lasts 4.5 billion years. Such a long destruction leads to low energy consumption.

If we consider the use of uranium compounds, its oxides come in handy. They are used in the glass industry.

Oxides act as dyes. Can be obtained from pale yellow to dark green. In ultraviolet rays, the material fluoresces.

This property is used not only in glasses, but also in uranium glazes for. Uranium oxides in them are from 0.3 to 6%.

As a result, the background is safe, does not exceed 30 microns per hour. Photo of uranium elements, more precisely, products with his participation, are very colorful. The glow of glasses and dishes attracts the eye.

Uranium price

For a kilogram of unenriched uranium oxide, they give about 150 dollars. Peak values ​​were observed in 2007.

Then the cost reached 300 dollars per kilo. The development of uranium ores will remain profitable even at a price of 90-100 conventional units.

Who discovered the element uranium, did not know what its reserves were in the earth's crust. Now, they've been counted.

Large fields with a profitable production price will be depleted by 2030.

If new deposits are not discovered, or alternatives to the metal are not found, its value will creep up.

A feature of the development of uranium deposits is the possibility of using for them both conventional mining methods of extraction (open and underground), and methods of underground (borehole, block) and heap leaching. Prevalence in the world of various methods of uranium mining: underground 37%, open pit 24%, associated mining 18%, borehole underground leaching 12%, undetermined 7%.

In the mining and production of uranium, various precautions are taken to protect the health of personnel:

• - Dust levels are carefully controlled to minimize the ingestion of γ- or α-emitting substances. Dust is the main source of radioactive exposure. It typically contributes 4 mSv/yr to the annual dose received by personnel.
• - The external radioactive exposure of personnel in mines, factories and waste disposal sites is limited. In practice, the level of external exposure from ore and waste is usually so low that it has little effect on increasing the allowable annual dose.
• - Natural ventilation of open deposits reduces the level of exposure from radon and its daughter isotopes. The level of exposure from radon does not exceed 1% of the level allowed for continuous exposure of personnel. Underground mines are equipped with ventilation systems to achieve the same level. In Australian and Canadian underground mines, the average exposure dose is ~3 mSv/year.
• - There are strict hygienic standards for the work of personnel with uranium oxide concentrate, because it is chemically toxic, like lead oxide. In practice, precautions are taken to protect the respiratory system from the ingress of toxins, similar to those used when working in lead smelters.

Let us dwell on the main methods of extracting uranium raw materials in more detail.

Mine method of uranium mining- one of the main ways of uranium production. The organization of work is similar to the methods of mining other metals, but there are differences. Uranium ores occur most often in the form of narrow layers, which leads to the formation of a mine in the form of branched drifts. Since the development of uranium ore is carried out on the same horizon with the formation of drifts and treatment blocks located near the main haulage, the formation of dust is largely localized. The absence of air circulation from one block to another does not cause their mutual pollution, and the formation of dust in uranium mines is not great.

During the operation of underground uranium mines, the mine waters of the mine are constantly pumped out and sent to the hydrometallurgical plant in the system of closed technological water circulation. Powerful ventilation does not allow the concentration of radon in the air. If ventilation is turned off after the end of the work shift, then the atmospheric concentrations of radon and its daughter products increase sharply, and therefore, before the start of the next shift, these concentrations must be reduced to the maximum allowable

The main danger to uranium miners comes from inhaling air containing radon released from the ore. In addition to uranium, uranium ores contain all other members of the radioactive series, in which it is the parent nuclide. The following elements of this family pose the greatest danger to the health of miners: 222 Rn, 21t *Pb, 211 Bi and 21 "Po. The content of radon in the atmosphere of the mine is determined by the rate of emanation, the rate of ventilation and the half-life of radon. The immediate progeny of radon decay have a short half-life and quickly accumulate in the atmosphere, even if radon enters the mine without progeny.

Due to the fact that the relative harmfulness of radon daughter products is greater than the harmfulness of radon itself, control over radioactive air pollution in uranium mines can be carried out by its decay products. As an acceptable working level of the content of daughter products of radon decay in the mine atmosphere, the value of "latent energy", equal to 1.3 * 105 MeV / l of air, is proposed.

Open pits (some of them up to 500 m deep) are a popular way to mine uranium. It is believed that the radiation hazard of such quarries for miners is much less than underground mines. However, for the environment, open-pit mining of uranium can pose a serious danger due to dust entrainment. Landscape changes, vegetation disturbance, adverse impacts on local fauna are inevitable consequences of open pit mining. It is a difficult task to backfill the quarry with waste rock and recultivate after the completion of mining operations.

There are rules and laws that define measures to protect the environment, stipulate requirements such as preliminary

environmental impact assessments; gradual implementation of a restoration program, including restoration of landscapes and forest areas, planting of endogenous flora, restoration of endogenous wildlife; as well as checking the compliance of the state of the environment with existing regulations.

Rice. four. Extraction of uranium by underground leaching.

Mining by dissolution

(in situ leaching) involves introducing an alkaline or acidic liquid (such as sulfuric acid) through boreholes into a uranium ore deposit and pumping it back out. This method does not require removal of the ore from the mining site, but can only be used where the uranium deposits are located in an aquifer in permeable rock and not too deep (-200 m).

The advantages of this technology are a reduced risk of accidents and exposure for personnel, low cost, and no space required for waste storage. The main disadvantages are the risk of diversion of leaching fluids from the uranium deposit and subsequent contamination of groundwater, and the impossibility of restoring natural conditions in the leaching zone after the completion of operations. The resulting contaminated mixture is either transferred to reservoirs or sent to deep liquidation wells.

Leaching - extraction of one or more components from ores, concentrates, production wastes with an aqueous solution containing an alkali, acid or other reagent, as well as using certain types of bacteria; a special case of extraction from the solid phase. Usually, leaching is accompanied by a chemical reaction, as a result of which the extracted component passes from a form that is insoluble in water to a soluble one.

Underground leaching - leaching at the place of occurrence of uranium ores. It involves injecting sulfuric acid into the ore mass and eliminates the problem of tailings storage, but under adverse conditions can cause groundwater pollution.

Leaching is based on the ability of the extracted substance to dissolve better than the rest. Solvents - a solution of ammonia, acids, alkalis, metal chlorides or chlorine, sulfates, etc. Leaching may be accompanied by the oxidation of the extracted material in order to convert sparingly soluble compounds into easily soluble ones (oxidative leaching). Gases (air, oxygen), liquid and solid inorganic substances (HN0 3 , Mn0 2 , KMn0 4 , etc.), bacteria (bacterial leaching) are used as an oxidizing agent.

Borehole underground leaching is used in the development of reservoir deposits. The conditions for its applicability are the high permeability and water content of the ore-bearing medium. When using this method, the field is divided into polygons, drilled successively by systems of injection and extraction wells, and there are two or three or more extraction wells for one injection well. The leaching time of uranium from rocks at each test site is 1^-3 years. Depending on the composition of the working solutions used, an acid uranium leaching scheme (solutions of sulfuric acid) and a carbonate scheme (solutions of sodium and ammonium carbonates-bicarbonates) are distinguished.

Underground leaching consists in supplying a leaching solution underground directly into the ore body or into a layer of specially prepared ore and pumping the solution that has seeped through the ore layer to the surface. There are two main options for underground leaching - downhole (shaftless) and mine (block). In underground mines, old or specially created mines, prepared underground chambers with collapsed ore are used, and adits or drifts are used to collect the production solution.

Underground leaching, which is usually used at an ore body depth of no more than 1000 m, makes it possible to involve low-grade uranium ores in the mining industry, drastically reduce the volume of capital investments and the construction time of enterprises, increase labor productivity by several times, significantly reduce the harmful impact on nature (do not violate landscape, drastically reduce the amount of solid waste and harmful substances brought to the surface of the earth, and it is relatively easy to restore waste areas).

Underground borehole leaching is a method of developing ore deposits without raising the ore to the surface by selectively transferring natural uranium ions into a productive solution directly in the subsoil. This method is carried out by drilling wells through uranium ore bodies, supplying a solution to uranium ore bodies, lifting uranium-containing solutions to the surface and extracting uranium from them in sorption ion-exchange units, adding acid to mother liquors and pumping them back into the bowels. During borehole leaching, there is no change in the geological state of the subsoil, since the mining mass is not excavated.

In the process of borehole leaching, less than 5% of radioactivity passes into a mobile state in the subsoil and is brought to the surface, compared with 100% with traditional methods of uranium mining. There is no need to build tailings for storing waste with a high level of radiation. The natural hydrogeochemical environment in uranium deposits is usually capable of self-healing from technogenic impact. Due to the gradual restoration of natural redox conditions, a slow but irreversible process of reclamation of groundwater in ore-bearing aquifers occurs. There are methods of significant intensification of this process, accelerating reclamation tenfold.

Nevertheless, the borehole leaching method is quite dangerous from an environmental point of view. Leaching uranium-containing solution can flow out of the ore body of the zone through fractures in the rock or ruptures in waterproofing layers and then spread through the aquifer. This can lead to contamination of groundwater at long distances from the mine. In addition to uranium leaching solutions, other minerals also dissolve, as a result of which not only uranium becomes mobile, but also elements: radium, arsenic, vanadium, molybdenum, cadmium, nickel, lead, etc., and they are concentrated a thousand times. Minerals precipitate out of solution during the in-situ leaching process, forming calcite, gypsum and other minerals. The resulting precipitation can reduce or even completely block the flow of solution through uranium-bearing areas, leading to unpredictable results or premature closure of the mine.

Borehole leaching produces large quantities of wastewater and brines that must be disposed of in an environmentally sound manner. These include wash water and liquid waste from the uranium enrichment plant. These fluids are mixed and re-injected into the same groundwater used in uranium mining, or injected into a deep aquifer far away from other groundwater users. These liquid wastes contain high concentrations of radionuclides and heavy metals, and the area of ​​their distribution needs to be restored after the closure of the mine.

Heap leaching is the process of obtaining useful components by dissolving prepared (crushed poor ores or tailings of a processing plant) and placed in a special pile of mineral raw materials, followed by their separation (precipitation) from circulating solutions.

Heap leaching is used to process ores containing readily soluble useful components; such ores must be relatively porous and inexpensive. Occasionally, heap leaching is used to treat tailings resulting from prior mining processes. To load the ore, a slightly inclined surface is prepared, impervious to leaching solutions. Drainage basins are created along and across this surface for drainage. After loading, the ore is poured with an amount of leaching solution sufficient to saturate its entire thickness. The solution penetrates between the ore particles and produces the dissolution of useful components. After a certain period of time, the material is dried and the crust formed by the dissolved valuable components is removed, and the treated loose rock is washed into the drainage system.

Percolation leaching is used in the processing of ores that do not grind well when crushed and do not contain natural sludge or clay. This is a rather slow process. Seepage leaching is carried out in tanks that are well adapted for loading and unloading. The bottom of the tank should be an effective filter, allowing pumping and pumping of the solution through it. The tanks are loaded with crushed ore of a certain size fraction. Then the leaching solution is pumped into the tank and absorbed into the ore After the required holding time has elapsed, the solution with the leached components is pumped out, and the ore is washed to remove the remaining leaching solution.

During the leaching process, emissions of dust, radon and leaching liquid are possible. After the completion of the leaching process, especially if the ore contains iron sulfide, then after its access to water and air, continuous bacterial production of acid in the dumps can begin, which leads to spontaneous leaching of uranium for many centuries with contamination of groundwater.

At present, nuclear energy is used on a fairly large scale. If in the last century radioactive materials were used mainly for the production of nuclear weapons, which have the greatest destructive power, then in our time the situation has changed. Nuclear energy at nuclear power plants is converted into electrical energy and used for completely peaceful purposes. Nuclear engines are also being created, which are used, for example, in submarines.

The main radioactive material used for the production of nuclear energy is Uranus. This chemical element belongs to the actinide family. Uranium was discovered in 1789 by the German chemist Martin Heinrich Klaproth while studying pitchblende, which is now also called "tar pitch". The new chemical element was named after a recently discovered planet in the solar system. The radioactive properties of uranium were discovered only at the end of the 19th century.

Uranium is contained in the sedimentary shell and in the granite layer. This is a rather rare chemical element: its content in the earth's crust is 0.002%. In addition, uranium is found in insignificant amounts in sea water (10 −9 g/L). Due to its chemical activity, uranium is found only in compounds and does not occur in free form on Earth.

uranium ores called natural mineral formations containing uranium or its compounds in quantities in which it is possible and economically feasible to use it. Uranium ores also serve as raw materials for the production of other radioactive elements, such as radium and polonium.

Nowadays, about 100 different uranium minerals are known, 12 of which are actively used in industry to obtain radioactive materials. The most important minerals are uranium oxides (uranite and its varieties - pitchblende and uranium black), its silicates (coffinite), titanites (davidite and brannerite), as well as hydrous phosphates and uranium mica.

Uranium ores are classified according to various criteria. In particular, they are distinguished by the conditions of education. One of the types is the so-called endogenous ores, which were deposited under the influence of high temperatures and from pegmatite melts and aqueous solutions. Endogenous ores are characteristic of folded areas and activated platforms. Exogenous ores are formed in near-surface conditions and even on the Earth's surface in the process of accumulation (syngenetic ores) or as a result (epigenetic ores). Occur mainly on the surface of young platforms. Metamorphogenic ores that arose during the redistribution of primary dispersed uranium in the process of metamorphism of sedimentary strata. Metamorphogenic ores are characteristic of ancient platforms.

In addition, uranium ores are divided into natural types and technological grades. By the nature of uranium mineralization, they distinguish: primary uranium ores - (U 4 + content is not less than 75% of the total), oxidized uranium ores (mainly contain U 6 +) and mixed uranium ores, in which U 4 + and U 6 + are in roughly equal proportions. The technology of their processing depends on the degree of oxidation of uranium. According to the degree of uneven content of U in the lumpy fraction of the mountain (“contrast”), very contrasting, contrasting, weakly contrasting and non-contrasting uranium ores are distinguished. This parameter determines the possibility and expediency of enrichment of uranium ores.

According to the size of aggregates and grains of uranium minerals, the following are distinguished: coarse-grained (over 25 mm in diameter), medium-grained (3–25 mm), fine-grained (0.1–3 mm), fine-grained (0.015–0.1 mm) and dispersed (less than 0.015 mm) uranium ores. The size of grains of uranium minerals also determines the possibility of enrichment of ores. According to the content of useful impurities, uranium ores are divided into: uranium, uranium-molybdenum, uranium-vanadium, uranium-cobalt-bismuth-silver and others.

According to the chemical composition of impurities, uranium ores are divided into: silicate (consist mainly of silicate minerals), carbonate (more than 10–15% of carbonate minerals), iron oxide (iron-uranium ores), sulfide (more than 8–10% of sulfide minerals) and caustobiolitic composed mainly of organic matter.

The chemical composition of ores often determines the way they are processed. From silicate ores, uranium is separated by acids, from carbonate ores by soda solutions. Iron oxide ores are subjected to blast-furnace smelting. Caustobiolitic uranium ores are sometimes enriched by incineration.

As mentioned above, the content of uranium in the earth's crust is quite low. There are several uranium ore deposits in Russia:

Zherlovoye and Argunskoye deposits. They are located in the Krasnokamensky district of the Chita region. The reserves of the Zherlovoye deposit are 4,137 thousand tons of ore, which contain only 3,485 tons of uranium (average content 0.082%), as well as 4,137 tons of molybdenum (content 0.227%). The reserves of uranium at the Argunskoye deposit in category C1 are 13,025 thousand tons of ore, 27,957 tons of uranium (average grade 0.215%) and 3,598 tons of molybdenum (average grade 0.048%). C2 category reserves are: 7990 thousand tons of ore, 9481 tons of uranium (with an average grade of 0.12%) and 3191 tons of molybdenum (average grade of 0.0489%). Approximately 93% of all Russian uranium is mined here.

5 uranium deposits ( Istochnoe, Kolichkanskoe, Dybrynskoe, Namarusskoe, Koretkondinskoe) are located on the territory of the Republic of Buryatia. The total explored reserves of the deposits amount to 17.7 thousand tons of uranium, the predicted resources are estimated at another 12.2 thousand tons.

Khiagdinsky uranium deposit. Extraction is carried out by the method of borehole underground leaching. The explored reserves of this field in category C1 + C2 are estimated at 11.3 thousand tons. The deposit is located on the territory of the Republic of Buryatia.

Radioactive materials are used not only to create nuclear weapons and fuel. For example, uranium is added in small amounts to glass to give it color. Uranium is a constituent of various metal alloys and is used in photography and other fields.

How much ore is required to produce low enriched uranium as fuel for a nuclear power plant? It is generally accepted that fuel uranium is uranium, the content of the uranium-235 isotope in which is brought to 4%. In natural ore, this isotope is only 0.7%, that is, it is required to increase its concentration by 6 times.

Let me remind you that until the 1980s, Europe and the USA enriched uranium only on "grids", spending a huge amount of electricity on this work. A technological moment, but, as they say, with great consequences. Natural uranium hexafluoride can be "sucked out" by the 235th isotope until it stops - so that the minimum amount remains in the "tails". But what does this mean in the case of the diffusion method? More "grids", more containers for the original hexafluoride and, of course, more energy costs. And all this increases the cost, spoils economic indicators, reducing profits. Not interesting in general. Therefore, in the western "tails" of uranium-235 - 0.3%, and 0.4% goes into further work. With such “tails”, the picture is as follows: 1 kg of LEU requires 8 kg of ore + 4.5 SWU (separation work units).

For quilted jackets, the picture was and remains somewhat different - after all, the work of our “needles” is much less expensive. Remember - the "needle" requires 20-30 times less electricity per 1 SWU. There was no point in saving separation work, the original uranium hexafluoride was “squeezed out” more carefully: 0.2% uranium-235 remains in our “tails”, 0.5% was spent on further enrichment work. It would seem that the difference is only 0.1%, why pay attention to such a trifle? Yes, not everything is so simple: on our "needles" to obtain 1 kg of LEU, 6.7 kg of ore + 5.7 SWU are required. 1.3 kg less ore - that is, we treated our bowels much more prudently than the Democrats.

But that's not all. 1 SWU on our centrifuges costs about 20 dollars, on "grids" 1 SWU cost from 70 to 80. This means that for the West a uranium deposit, in which the cost of ore, say, 100 dollars, is very expensive. Let's calculate 1 kg LEU on a calculator to make it clear.

1 kg LEU = 8 kg ore + 4.5 SWU, i.e.

1 kg LEU \u003d 8 x 100 + 4.5 x 70 \u003d $ 1,115.

And now we put our numbers and we get:

1 kg LEU = 6.7 kg ore + 5.7 SWU

1 kg LEU = 6.7 x 100 + 5.7 x 20 = $784

This means that the uranium deposit, which was too expensive for us for the civilized West, is the very thing. Roughly, there is MORE uranium on Earth for our technology than for Western technology. From the moment when Europe mastered Zippe's centrifuges, uranium reserves in world statistics have increased dramatically, although the geologist brothers did not lift a finger for this: previously discovered deposits began to be recognized as commercially profitable, that's all. But URENCO turned on its centrifuges in the 80s, and nuclear power plants in Europe and the States appeared much earlier, right? This means that since the end of the 40s of the last century, uranium deposits have been exploited extremely sweepingly, without saving on natural ores. Roughly speaking, the West "killed" one field after another, jumping to new ones. And the terribly uneconomical Mordor was in no hurry: they found a deposit and sucked it to the bottom, without fuss and without haste. At the same time, we must not forget that throughout the years of the Cold War, the nuclear countries were very actively increasing their stocks of weapons-grade, highly enriched uranium, and this requires much more natural uranium ore. Roughly, 275 kg of ore is consumed per 1 kg of HEU, and the HEU account in the countries of the nuclear club was hundreds of tons. And HEU isn't just a weapon, it's powered by submarine reactors, it's powered by a lot of research reactors. In general, humanity spent its uranium ores very, very intensively, and all that we can say in our defense is that we were not the first to start.

There is one more thing you need to know about. When we are told: “so many tons of uranium ore have been mined”, it is important to understand that we are not talking about mountains of some kind of pebbles or metal ingots. In the uranium industry, all ore reserves are traditionally converted into uranium concentrate - more precisely, U3 O8, nitrous oxide. Traditionally, it was a yellow powder and was called "yellow cake", but now this is a bit outdated. In the process of ore beneficiation, a whole cycle of its processing is used, one of the components of which is roasting. In recent years, different temperatures have been used at different plants, so the color of the uranium concentrate is very different - from dark green to black. But the procedure for processing ore is a separate topic, quite a large one, and for now we are trying to deal with deposits and production. Put it aside, but remember: all talk about uranium ore is talk about uranium concentrate. And rightly so - these ores are very different, they contain too different amounts of uranium, so it was impossible to do without such a “standardization”.

When did people discover this metal and why is it actually called "uranium"? The story is old but interesting. It is now that we all know what radiation is and quite rightly we cannot tolerate it and are afraid of it. And in earlier times, people didn’t know anything about radiation - maybe that’s why they didn’t suffer from it? .. Among the ores and minerals in silver mines, medieval miners often found a heavy black mineral - the so-called tar blende. It is known for sure that the snag has been known since 1565 - then it was discovered in the Ore Mountains of Saxony, but they did not come up with any special application for it. In 1789, the German analytical chemist Martin Klaproth became interested in this mineral and decided to analyze it properly chemically. The ore was brought to his laboratory from the Jakhimovo mine in what is now the Czech Republic. Becquerel and Curie later made their discoveries on minerals from the same Jakhimivo, so I propose to write it down like this:

The "homeland" of uranium is the Czech Republic.

Martin Klaproth

Klaproth worked very diligently: he melted minerals at different temperatures, with and without air, poured all sorts of acids and aqua regia, until, in the end, he got a sintered mass with clearly visible grains of metal. It was in 1789 - 8 years after astronomers discovered a previously unknown planet, which they called Uranus. Here is what Klaproth himself wrote about this: “Previously, the existence of only 7 planets was recognized, corresponding to 7 metals, which bore the names of the planets. In this regard, it is advisable, following the tradition, to name the new metal after the newly discovered planet. The word 'uranium' comes from the Greek word for 'sky', and thus may refer to the heavenly metal." They do not argue with the discoverers - so we are now dealing with this very “heavenly metal”.

Klaproth himself, however, failed to obtain pure uranium; this was achieved only in 1840 by E.M. Peligo. In 1896, Becquerel discovered that uranium compounds irradiate photographic paper - this is how the study of radioactivity began. To the most formidable and terrible weapon, to the largest "reserve of energy" humanity moved slowly ...

uranium ore

From the point of view of geologists on Earth, uranium ore is not just a lot, but a lot. But not every uranium mineral gets the proud name "ore": minerals in which there is very little uranium and a lot of waste rock are not considered ores. Good ores are considered to be minerals in which there is more than 0.1% uranium (1 kg per 1000 kg of rock), but there are exceptions. For example, in South Africa, at the Witwatersland deposit, uranium is mined from ore, in which its concentration is only 0.01%, and is mined on an industrial scale. How so? Yes, this heavenly metal is not simple - it is often found in the same rocks where gold is found. Since gold is “picked out” from this rock, why not “pick it up” to the heap and uranium - that's the logic. Gold as the main purpose of ore processing, uranium as a side. "Often" also has a numerical value: 12% of the uranium mined in the world is a by-product of gold and other mines. In the USA, for example, uranium is obtained from rocks with a concentration of 0.008% in general - from Florida phosphorites. The main production is phosphorus, uranium - to the heap ... Well, if you do not touch on such exotic things, then uranium ores are divided into 4 types-grades according to their content: rich - with a uranium content of more than 1%; privates - from 0.1 to 1.0%; the poor - from 0.03 to 0.1% and the poor - less than 0.03%.

And uranium ores are divided into 5 classes, depending on which technology is used to extract and process heavenly metal. Roughly - what kind of processing plants should be created next to the deposits. This is also such a tradition: since the concentration of uranium is always small, no one thinks to transport millions of tons of rock anywhere. Mine, mine, quarry and end-to-end - everything you need for processing.

However, these are not all types of classification of uranium ores: since we all live in a world where profit is most important, perhaps the main classification is by the cost of the final product (that very uranium concentrate, yellow cake). A kind of generalizing indicator, in which all details are discarded - what was the concentration of uranium in the ore, how it was mined and purified, what the infrastructure cost. It doesn't matter what happened BEFORE, what matters is how the result turned out. There are only 3 categories: 1) deposits where the cost of 1 kg of concentrate is less than $40 per kg; 2) where the cost is from 40 to 80 dollars per kilo; 3) where the cost price is from 80 to 130 dollars per kilo. Everything that is more expensive than $ 130 is “non-shield” today, because it is very expensive. But how long will such neglect-superficiality last? Until 2006, the IAEA considered uranium super-expensive and at a price of more than $80/kg, but now it has decided that it is necessary to evaluate centrifuges according to their merits - the low cost of enrichment makes it possible to safely use ore more than $80. Our 10th generation centrifuges have just begun to be used, therefore it cannot be ruled out that after some time the $130 bar will no longer be “cut-off”. In the realm of darkness and horror with an economy torn to shreds, the industrial operation of the BN-800 fast neutron reactor began, the BN-1200 is being designed, in 2020 it is also planned to launch a lead reactor under the Proryv project, by 2030 there is hope for the implementation of a closed nuclear cycle.

However, let's not indulge in projects and hypotheses - let's focus on what we have today. In 2006, it was believed that there were 5,000,000 tons of uranium ores on the third planet from the Sun, the next IAEA report was released in 2010. It was in this report that centrifuges were recognized for the first time as the only method of uranium enrichment today, for the first time the "cut-off" bar was raised from $80/kg to $130/kg. The new figure for uranium ore reserves on Earth is 6,306,300 tons. I repeat - this is not an increase due to new deposits, this is the conversion of geological ores into industrial ones. And it took place for a simple reason - the IAEA recognized that everything except centrifuges is evil, and we will no longer remember it. The increase in recoverable ores amounted to 26% - without additional investment in exploration.

Not so often in the history of civilization, the development of technology has had a serious impact on geopolitics, and uranium and centrifuges are the same case. Let's figure out on our fingers what the emergence of commercial interest in uranium deposits, which until then had remained untouched for many years, means? Firstly, the countries of the "atomic club" saw their interest in those territories where these deposits were located. For example, deposits in the Kirovograd region have become interesting not only for Ukraine ... Secondly, the countries that were not members of the "atomic club" saw that uranium could be enough for them. And this is not my theoretical fabrication: delegations from 52 countries attended the just-past Atomexpo-2016, and only 32 countries had nuclear power at least in some form. 20 countries are newcomers who have sensed the prospect.

Calculator

What is interesting in uranium - let the calculator tell. We have 6,306,300 tons of ore, in which the content of uranium-235 (which, in fact, “burns” in nuclear power plant reactors) averages 0.72%. Therefore, if all uranium ore is converted into uranium-235, we have 45,405 tons of it. In terms of energy cost, 1 ton of uranium-235 corresponds to 2,000,000 tons of gasoline. Accordingly, the conversion of uranium-235 reserves into oil equivalent is 90.81 billion tons of oil. Is it a lot or a little? The explored oil reserves on Earth today are 200 billion tons. Uranium reserves are almost half, almost 50%. And what are the prospects? The technology of oil production has been brought to almost perfection, the technology of its processing is similar. In order to increase oil reserves, one must either a) continue to look for more and more new deposits, which, at current hydrocarbon prices, has been slowing down for two years now; b) agree that oil will only rise in price over the years, since there is less and less of it. Shale oil, which the Bolsheviks, Mensheviks and others talk about so much, is not interesting at the current price level, but sooner or later the moment will come when its reserves will have to be used, and not only in the United States.

But with uranium - a somewhat different picture, much less unambiguous. We have not yet been disclosed what the cost of 1 SWU will be on the latest generations of Rosatom centrifuges - and we have already seen how enrichment technology can increase uranium ore reserves. The operation of the BN-800 has just begun, the BN-1200 is still only in the drawings, we will see the results of the Proryv project only in 2020. But let's, without undue modesty (as much as possible, after all), state a historical fact: during the entire existence of the nuclear project, there were no mistakes in the development of technologies by the former Ministry of Medium Machine Building, the former Ministry of Atomic Energy and the current Rosatom. Certain shortcomings, flaws - yes, there were, but the general line of development, let's face it, did not break even once.

There are simply no reasons not to believe that Rosatom's struggle for a closed nuclear cycle will end in success - in my opinion, of course. Do you think this statement is too bold? And let's look around, for a moment allowing ourselves to forget that the main achievement of mankind is the latest iPhone model. Not only do they believe in the reliability of our technologies, but they sign contracts for the construction of nuclear power plants, not only "old customers" - such as Hungary, Iran and Finland, China and India. For the first time, nuclear power plants will appear in Egypt, Vietnam, Belarus, Turkey, Bangladesh, Indonesia - and these will be Russian-made nuclear power plants. So, I'm not the only one who believes in our technologies, in their progressive development. And I am not the only one who is confident that with the next leap in the development of technologies, uranium reserves may turn out to be greater than hydrocarbon reserves ... And let's not discount one more possible uranium reserve - new deposits. There is, for example, a country where the level of development of the territory by geological exploration still does not greatly exceed 60% - Russia. There are countries where there is no time for geological exploration at all - for example, Afghanistan, Eritrea.

But considering the prospects for nuclear energy is a separate and very serious topic that should be left for later. And this note is an introductory note to Uranium Dungeons, in which I want to offer to see: what was, what has become, and how we have come to such a life. And, of course, without stories about new iPhones from the mighty USA, things will not do either. I have them and, as usual, it was not necessary to invent anything.

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In the last few years, the topic of nuclear energy has become increasingly relevant. For the production of atomic energy, it is customary to use a material such as uranium. It is a chemical element belonging to the actinide family.

The chemical activity of this element determines the fact that it is not contained in a free form. For its production, mineral formations called uranium ores are used. They concentrate such an amount of fuel that allows us to consider the extraction of this chemical element as economically rational and profitable. At the moment, in the bowels of our planet, the content of this metal exceeds the reserves of gold in 1000 times(cm. ). In general, deposits of this chemical element in soil, water and rock are estimated at more than 5 million tons.

In the free state, uranium is a gray-white metal, which is characterized by 3 allotropic modifications: rhombic crystal, tetragonal and body-centered cubic lattices. The boiling point of this chemical element is 4200°C.

Uranium is a chemically active material. In air, this element slowly oxidizes, easily dissolves in acids, reacts with water, but does not interact with alkalis.

Uranium ores in Russia are usually classified according to various criteria. Most often they differ in terms of education. Yes, there are endogenous, exogenous and metamorphogenic ores. In the first case, they are mineral formations formed under the influence of high temperatures, humidity and pegmatite melts. Exogenous uranium mineral formations occur in surface conditions. They can form directly on the surface of the earth. This is due to the circulation of groundwater and the accumulation of precipitation. Metamorphogenic mineral formations appear as a result of the redistribution of initially spaced uranium.

According to the level of uranium content, these natural formations can be:

• super-rich (over 0.3%);
• rich (from 0.1 to 0.3%);
• ordinary (from 0.05 to 0.1%);
• poor (from 0.03 to 0.05%);
• off-balance sheet (from 0.01 to 0.03%).

Modern applications of uranium

Today, uranium is most commonly used as fuel for rocket engines and nuclear reactors. Given the properties of this material, it is also intended to increase the power of a nuclear weapon. This chemical element has also found its application in painting. It is actively used as yellow, green, brown and black pigments. Uranium is also used to make cores for armor-piercing projectiles.

Uranium ore mining in Russia: what is needed for this?

The extraction of radioactive ores is carried out by three main technologies. If ore deposits are concentrated as close as possible to the surface of the earth, then it is customary to use open technology for their extraction. It involves the use of bulldozers and excavators that dig large holes and load the resulting minerals into dump trucks. Then it goes to the processing complex.

With a deep occurrence of this mineral formation, it is customary to use underground mining technology, which provides for the creation of a mine up to 2 kilometers deep. The third technology differs significantly from the previous ones. In-situ leaching for the development of uranium deposits involves drilling wells through which sulfuric acid is pumped into the deposits. Next, another well is drilled, which is necessary for pumping the resulting solution to the surface of the earth. Then it goes through a sorption process, which allows collecting salts of this metal on a special resin. The last stage of the SPV technology is the cyclic treatment of the resin with sulfuric acid. Thanks to this technology, the concentration of this metal becomes maximum.

Deposits of uranium ores in Russia

Russia is considered one of the world leaders in the extraction of uranium ores. Over the past few decades, Russia has consistently been in the top 7 leading countries in this indicator.

The largest deposits of these natural mineral formations are:

The largest uranium mining deposits in the world - leading countries

Australia is considered the world leader in uranium mining. More than 30% of all world reserves are concentrated in this state. The largest Australian deposits are Olympic Dam, Beaverley, Ranger and Honeymoon.

Australia's main competitor is Kazakhstan, which contains almost 12% of the world's fuel reserves. Canada and South Africa each contain 11% of the world's uranium reserves, Namibia - 8%, Brazil - 7%. Russia closes the top seven with 5%. The leaderboard also includes countries such as Namibia, Ukraine and China.

The world's largest uranium deposits are:

Reserves and production volumes of uranium ore in Russia

Explored reserves of uranium in our country are estimated at more than 400,000 tons. At the same time, the indicator of predicted resources is more than 830 thousand tons. As of 2017, there are 16 uranium deposits operating in Russia. Moreover, 15 of them are concentrated in Transbaikalia. The Streltsovskoye ore field is considered the main deposit of uranium ore. In most domestic deposits, mining is carried out by the mine method.

• Uranus was discovered in the 18th century. In 1789, the German scientist Martin Klaproth managed to produce metal-like uranium from ore. Interestingly, this scientist is also the discoverer of titanium and zirconium.
• Uranium compounds are actively used in the field of photography. This element is used to color positives and enhance negatives.
• The main difference between uranium and other chemical elements is natural radioactivity. Uranium atoms tend to change independently over time. At the same time, they emit rays invisible to the human eye. These rays are divided into 3 types - gamma, beta, alpha radiation (see).