Rock salt (halite, Halite) is one of the most abundant minerals on earth. The chemical formula of NaCl is sodium chloride. A substance of natural origin, the main deposits are concentrated in places where in ancient times there were seas and oceans. The formation of new deposits is ongoing, salt lakes, seas, estuaries are potential deposits. At the moment, elite varieties of edible salt are mined in existing lakes, and the underlying reserves are a zone of halite formation.
Origin
Halite has surface and mineral deposits. Surface deposits are divided into ancient deposits and modern formations. The ancients are mainly represented by rock salt of sedimentary origin in the places of the once-existing bays, lakes, sea lagoons at a time when the planet was dry and very hot, which caused intense evaporation of water.
Fossil deposits occur in strata, rods or domes below the surface of the earth in the environment of sedimentary rocks. Layers of fossil salt have a layered structure, interspersed with clay, sandstone. The domed arrangement of halite is formed due to the movement of rocks, when the overlying strata, moving, push softer deposits of rock salt into the weakened zones, resulting in a dome. The size of the dome halite can reach several tens of kilometers.
Types of Halite
Mineral halite is distinguished into primary and secondary. Primary was educated from the brine of ancient salt basins and has interspersed with other minerals. Secondary, later halite, was formed as a result of redeposition of primary halite and is characterized by a high content of bromine.
The mineral of secondary origin has a transparent, coarse-grained structure and forms large nests in the thickness of rock salt. When developing deposits, the large nests of halite of secondary origin that have come across sometimes surprise with the beauty and clarity of lines, and the diversity of the color palette. Halite is located in vein deposits in the form of veins, while its structure is denser, white, sometimes the peripheral endings turn blue, which may indicate radioactivity.
Mineral characteristics
Halite has a glass luster, a hardness index of 2, the specific gravity of the mineral is 2.1-2.2 g / cm 3 . The crystals are white, gray, pink, blue, red / tint or colorless. In the mass, the nugget can be painted in several colors. Crystal halite is soldered in three directions on any face of the cube. It is found in nature in the form of stalactites, drusen, crystals, deposits, swellings, etc.
The mineral has an ionic crystal lattice consisting of positively charged sodium ions and negatively charged chlorine ions. It tastes salty, has a solid structure, dissolves completely in water, giving a precipitate of impurities, at an increased concentration it precipitates in the form of crystals or flakes.
Place of Birth
Two of the world's largest halite deposits are located in the Volgograd region of the Russian Federation, one is located on Lake Baskunchak, the second - on Lake Elton. One of the long-discovered salt mines is the Sol-Iletsk deposit in the Orenburg region and the Usol deposit in Yakutia. In Ukraine, Slavyan-Artyomovsk and Prikarpatskoye deposits are being developed.
Large area reservoirs are located in Germany and Austria. In the United States, extensive halite reserves are located in the states of Kansas, Oklahoma and the Saskatchewan Basin in Canada.
The main scope
Halite salt is most often used as a reagent in the fight against ice on roads. The climatic conditions of most of the territory of Russia are characterized by long periods of cold, atmospheric precipitation, forming an ice shell. Given the length of the motorways, no equipment is able to provide quick cleaning of the roadway. The use of halite-based mixtures helps to quickly and effectively cope with ice and ensure traffic safety.
Technical halite salt has the following advantages:
- Ease, universality of use.
- Preservation of reagent qualities at low temperatures (up to -30 ° ).
- Environmental Safety.
- Low consumption.
- Low cost.
- General availability.
Application features
Processing the roadway with halite-based reagent provokes the formation of slurry, which destroys the ice crust, tightly adhered to asphalt. The lack of reagent can be considered solidification of the entire mass (reagent and melted ice) at temperatures below -30 ° C.
For better cleaning of roads, salt halite is mixed with sand or stone chips, which allows faster and better cleaning of asphalt from ice cover. According to technical specifications, no more than 150 grams of salt is required to clean one square meter of the road, which puts the mineral out of competition in comparison with other reagents. For domestic needs, especially in winter, you can purchase small packages of mineral reagent. Technical salt is halite, the price of which varies in retail from 5 rubles per kilogram, perfectly copes with the task.
Other areas of use
Technical salt (mineral halite) is used in industry in the following areas:
- Oil production. The main property of technical halite is the dissolution of ice, the softening of frozen or hardened soil. In winter or in the Far North, a solution of mineral salt under pressure is pumped into drilled wells, which greatly facilitates further work and saves other resources.
- Tablet halite is used for washing industrial boilers, heating systems in order to get rid of scale. Also, this compressed form of the mineral is used as a filter element for cleaning large volumes of water, for example in water wells. In addition to filtration, salt treatment eliminates the appearance of microbes and microorganisms in water. For domestic purposes it is used to reduce the hardness of hot water.
- Construction. Halite salt is used in the manufacture of silicate brick to give the final product resistance to sudden changes in temperature, strength characteristics also increase and the service life is extended. Brick with salt additive in production has a lower cost. The salt added to the cement mortar helps it to “grasp” faster, which speeds up the construction process and increases the durability and reliability of the construction.
In the world there are more than 14,000 areas where technical salt (halite) is used. In medicine, it is used for the production of saline solutions, antiseptics, preservatives for medicines. Technical salt has found application in the food industry as a refrigerant that allows you to quickly freeze and preserve foods at the appropriate temperature conditions.
Implementation
In the implementation, three types of mineral are distinguished, the differences are in the characteristics:
- The highest grade - the content of sodium chloride should be at least 97%, the content of external impurities is allowed no more than 0.85%.
- The first - at least 90% of calcium chloride in the mass, external impurities - 5%.
- The second - the minimum content of the main element should be about 80%, impurities in the amount of 12% of the total mass are allowed.
The amount of moisture for any variety is regulated at a level of not more than 4.5%. The price at which technical salt (halite) is sold depends on grade. The price per ton of raw materials ranges from 3500-3700 rubles (in packaging).
According to GOST, the storage and dispensing of the mineral is allowed in bulk, in tons, in polypropylene packaging of various weights. At the same time, salt packaged in bags has a limited shelf life of up to five years, while salt without packaging can be stored for a very long time.
The enterprises developing the deposits carry out the sale of the mineral by carriage standards for wholesale buyers, which allows increasing production. According to grade, the cost of such a mineral as salt (halite) is also determined. The price per ton when sold by wagon rates varies from 1,400 to 2,600 rubles.
In addition to technical applications, halite is sold as a necessary mineral supplement for animals; in this case, the pressed mineral is produced in briquettes.