When the radioactive elements of the periodic table were discovered, a person eventually came up with their application. This happened with uranium. It was used for both military and peaceful purposes. Uranium ore was processed, the resulting element was used in the paint and varnish and glass industries. After his radioactivity was discovered, they began to use it in nuclear energy. How clean and environmentally friendly is this fuel? They still argue about this.
Natural uranium
In nature, uranium does not exist in its pure form - it is a component of ore and minerals. The main uranium ore is carnotite and nasturan. Significant deposits of this strategic chemical element are also found in rare earth and peat minerals - orthite, titanite, zircon, monazite, xenotime. Uranium deposits can be found in rocks with an acidic environment and high concentrations of silicon. Its companions are calcite, galena, molybdenite, etc.
World deposits and reserves
To date, many deposits have been explored in a 20-kilometer layer of the earth's surface. All of them contain a huge number of tons of uranium. This amount is able to provide humanity with energy for many hundreds of years in advance. The leading countries in which uranium ore is in the largest volume are Australia, Kazakhstan, Russia, Canada, South Africa, Ukraine, Uzbekistan, the USA, Brazil, and Namibia.
Types of Uranium
Radioactivity determines the properties of a chemical element. Natural uranium is made up of its three isotopes. Two of them are the founders of the radioactive series. Natural uranium isotopes are used to create fuels for nuclear reactions and weapons. Uranium-238 also serves as raw material for the production of plutonium-239.
U234 uranium isotopes are daughter nuclides of U238. They are recognized as the most active and provide strong radiation. The U235 isotope is 21 times weaker, although it is successfully used for the above purposes - it has the ability to maintain a nuclear chain reaction without additional catalysts.
In addition to natural, there are artificial isotopes of uranium. Today, there are 23 known, the most important of them is U233. It is distinguished by the ability to activate under the influence of slow neutrons, while the rest requires fast particles.
Ore classification
Although uranium can be found almost everywhere - even in living organisms - the layers in which it is contained can be different in type. Production methods also depend on this. Uranium ore is classified by the following parameters:
- The conditions of formation are endogenous, exogenous and metamorphogenic ores.
- The nature of uranium mineralization is primary, oxidized and mixed uranium ores.
- The size of aggregates and grains of minerals is coarse-grained, medium-grained, fine-grained, fine-grained and dispersed ore fractions.
- The usefulness of impurities - molybdenum, vanadium, etc.
- The composition of impurities is carbonate, silicate, sulfide, iron oxide, caustobiolite.
Depending on how uranium ore is classified, there is a way to extract a chemical element from it. Silicate is treated with various acids, carbonate is treated with soda solutions, caustobiolitic is enriched by burning, and iron oxide is smelted in a blast furnace.
How uranium ore is mined
As in any mining business, there is a certain technology and methods for extracting uranium from the rock. It also depends on which particular isotope is in the lithosphere. Uranium ore is mined in three ways. It is economically justified to isolate an element from rock when it is contained in a volume of 0.05-0.5%. There is a mine, quarry and leaching method of extraction. The application of each of them depends on the composition of the isotopes and the depth of the rock. Quarry mining of uranium ore is possible with a shallow occurrence. The risk of exposure is minimal. There are no problems with equipment - bulldozers, loaders, dump trucks are widely used.
Mine mining is more complex. This method is used when the element lies at a depth of 2 kilometers and economic profitability. The rock must contain a high concentration of uranium in order to mine it was advisable. The adit provides maximum safety, this is due to the way uranium ore is mined underground. Workers are provided with overalls; the operating mode is strictly limited. The mines are equipped with elevators, reinforced ventilation.
Leaching - the third method - is the cleanest from an environmental point of view and the safety of employees of the mining enterprise. A special chemical solution is pumped through a system of drilled wells. It dissolves in the reservoir and is saturated with uranium compounds. Then the solution is pumped out and sent to manufacturing enterprises. This method is more advanced, it allows you to reduce economic costs, although there are a number of limitations to its application.
Deposits in Ukraine
The country turned out to be the happy owner of the deposits of the element from which nuclear fuel is produced . According to forecasts, uranium ores of Ukraine contain up to 235 tons of raw materials. Currently, only deposits have been confirmed, which contain about 65 tons. A certain amount has already been worked out. Part of the uranium is used domestically, part is exported.
The main deposit is considered the Kirovograd uranium ore district. The uranium content is small - from 0.05 to 0.1% per ton of rock, so the cost of the material is high. As a result, the obtained raw materials are exchanged in Russia for finished fuel elements for power plants.
The second major deposit is Novokonstantinovskoye. The uranium content in the rock allowed to reduce the cost compared to Kirovogradsky almost 2 times. However, since the 90s, development has not been carried out, all mines are flooded. Due to the aggravation of political relations with Russia, Ukraine may be left without fuel for nuclear power plants.
Russian uranium ore
In uranium mining, the Russian Federation is in fifth place among other countries in the world. The most famous and powerful ones are Khiagdinsky, Kolichkansky, Istochny, Koretkondinsky, Namarus, Dobrynsky (the Republic of Buryatia), Argunsky, Zherlovoye (Chita region). In the Chita region, 93% of all mined Russian uranium is mined (mainly through open pit and mine methods).
The situation with deposits in Buryatia and Kurgan is slightly different. Uranium ore in Russia in these regions lies in such a way that it allows the extraction of raw materials by leaching.
In total, deposits of 830 tons of uranium are forecasted in Russia; there are about 615 tons of confirmed reserves. These are deposits in Yakutia, Karelia and other regions. Since uranium is a strategic global raw material, the numbers may be inaccurate, since many data are classified, only a certain category of people has access to them.