Turkmenistan is rich in natural building materials such as limestone, marl, dolomite, granite, gypsum, refractory clay, quartz sand, gravel, and others.
In terms of this diversity, in an interview to CentralAsia.news, Allaberdi Ilyasov, a well-known Turkmen scientist, and doctor of technical sciences spoke about quartz sand. This natural substance is highly demanded in many sectors of the world economy. It is a loose material consisting of particles of minerals, no larger than 5 mm in size, of inorganic origin.
Industrial «wealth» of Turkmenistan
Nature generously endowed Turkmenistan with this strategic raw material resource. In general, the geography of Turkmenistan is rich in non-metallic materials that are successfully used in industry. Therefore, it would be useful to talk about their deposits.
Non-metallic building materials are represented in the territory of Turkmenistan by many deposits in different territorial areas. The largest ones are confined to the fans of the temporary drains of the Kopetdag mountains. The deposits are represented by sedimentary limestone, dolomite rocks of the cover, and igneous and metamorphic rocks of the Paleozoic basement and the Mesozoic-Cenozoic complex. The largest deposits are Sazakinsk, Ufrinsk, Kubatausk, Kernaysk.
Quartz sands with a high content of coloring oxides are concentrated in the Bakhardensk deposit, where the balance reserve is 2.5 million tons, and the Meaninsk deposit, where the reserves are 80 million tons. These deposits are associated with Paleogene marine deposits. The thickness of the seams is 57-72 meters.
Building sand deposits are confined to different genetic types of Quaternary deposits but are more often associated with eolian sediments of the Karakum desert and adjacent areas.
Industrial raw materials are, first of all, deposits of bentonite clays, kaolin, and quartz sands. The reserves of bentonite clays are concentrated in the Oglanlinsk deposit. Alkaline and alkaline-earth bentonites of marine volcanic-sedimentary genesis form a reservoir deposit with an average thickness of 10 m in the Upper Eocene deposits. The deposit of primary kaolins is associated with the kaolin zone of the Early Jurassic weathering crust along with the quartz-feldspar sandstones of the Triassic of the Tuarkyr region (Tuarkyrsk). The area of the deposit is 17 square kilometers, the depth is 80 meters, and the thickness is 10 meters. Inferred resources are 74 million tons.
At the southern end of the Karakum desert, there is the Anau quartz sand deposit, and at the Bezmeinsk deposit, there is barchan sand of eolian origin (feldspar quartz), which is necessary for obtaining continuous fibers.
Deposits of quartz sands and kaolin clays, enriched with quartz, are located in the north of western Turkmenistan (Karabogazgol, Tuvergur). The sands are concentrated in the form of a rampart and a terrace at the foot of the Gubadag, the Greater and Lesser Balkans, and the Western Kopetdag mountains. Their reserves are truly inexhaustible. Being inert materials, gravel sand impurities are the main source of their production.
Quartz sand is a loose material of the fine structure, obtained as a result of the destruction of quartz minerals. It differs from other types of sand in its high content of silicon dioxide or silica. Its main feature, which distinguishes it from many other types of sands of natural origin, is the fact that quartz sand is homogeneous and consists of only one mineral — quartz.
Naturally, this is not very easy to achieve: to obtain the desired sand with the required properties, the sand mined in quarries is washed, cleaned of impurities, and enriched using special electrochemical processes and installations. But first, let’s briefly understand what kind of material it is — quartz.
Quartz is a mineral belonging to the class of oxides. They make up about 17 percent of the mass of the earth’s crust. In addition to quartz, this group includes corundum, hematite, and 197 other minerals. Oxides are present in all types of rocks, such as granite or sandstone. The content of silicon dioxide in them reaches 65-75 percent. That is, we can say that any rocks are more than half composed of quartz.
Production of quartz sand
The most important feature of quartz is its high strength and complete inertness to the action of an aggressive environment, both acidic and alkaline. As a result of intense mechanical impacts, quartz is crushed and turns into sand. Despite its refractoriness and resistance to high temperatures, it can be melted. All these properties are used in the production of a wide range of materials of quartz sand.
Natural quartz sand is mined both in an open way from quarries, and in a closed way — in reservoirs using floating installations and dredgers. Subsequently, it is purified from numerous impurities, which form up to 90 percent of the total volume of the extracted material. Artificial quartz sand is made by crushing rocks containing a large percentage of quartz inclusions.
Mined or crushed quartz sand is additionally cleaned and sorted into fractions, each of which has its field of application. The processing of quartz sand is carried out in several stages. Multi-stage processing determines the rather high cost of prepared-pure quartz sand. The content of quartz in the prepared material reaches almost 100 percent, which is not the case in an ordinary quarry or river sand.
Efficiency and demand
Nowadays, in the whole world, the need for quartz sand, both natural and artificial, has increased many times over due to a wide range of applications in various industries. The annual global consumption of quartz sand has exceeded 1.2 million tons. The properties that have different volumes of particles of a given size determine where this raw material is applied.
A special and very important area of application of quartz sand is the purification of water from impurities with quartz sand. Quartz adsorbs harmful substances of the smallest fractions while maintaining its properties over a long time. The filtration properties of sand depend on the particle size: the smaller the grain diameter, the higher the filtration properties, since the fine fraction can retain the same small elements of contaminants in the water, which means that filtration with quartz sand will be more effective.
Quartz sand is widely used for swimming pool filters, repeatedly passing water through itself and cleaning it from emerging contaminants. Quartz sand has a huge intergranular porosity and a low bulk density, which makes it the main component in filtration. Such indicators make it possible not only to filter a large volume of water but also to improve its quality. Rounded quartz sand is washed out faster than crushed.
Quartz sand, which is immune to atmospheric, chemical, and physical actions, is not afraid of aggressive environments and high temperatures, which is why it is common in the production of cement, including Portland cements used in the grouting of gas and oil wells, bricks, asphalt, for the manufacture of decorative and finishing building materials. when plastering facade and interior interiors, for design work.
Areas of use
High levels of uniformity make it possible to add quartz sand to dry mixes, concrete, and polymer concrete, it is used in sandblasting as a bulk substance.
In construction, all material parameters are of great importance. Quartz sand is used in the manufacture of glass, faience and porcelain, fiberglass, enamel, paint, varnish products, and the foundry industry.
The largest end-user of quartz sand is the glass industry. It accounts for more than a third of the world market. Then comes the foundry industry, fracturing products, filtration products, and abrasives.
The construction sector, the automotive industry, and the technology market are increasingly using hybrid guide plates in computers, smartphones, and televisions. Solar control glazing for buildings and vehicles, lightweight construction glass, and advanced float glass technology are all areas where demand for high-quality quartz sand is on the rise.
The foundry uses molding quartz sand, the characteristics of which must comply with international quality standards.
Quartz sand is also widely used as a filler in the construction of polymer floors. As a binder, epoxy, polyurethane, or polyester resins are usually used. The filler is fine-grained dry quartz sand.
Quartz sand is also used for the production of refractory building materials. Due to its good abrasive properties, it is widely used for grinding lenses and other polished materials, and sawing stone.
Quartz sand is also used as an arc-extinguishing element in the production of electrical fuses. Recently, quartz sand has been increasingly used in the production of glass fiber pipes.
Thus, this strategic raw material resource, which Turkmenistan is so rich in, is used in many areas of the world economy. And that means it is a highly profitable export product.