Rock salt. What is rock salt - origin and extraction methods

Halite is a natural mineral of the halogen class, subclass sodium chloride. For an ordinary person, this is rock table salt, which is used daily for food. The history of the mineral goes back to the era of the origin of life on the planet, when the water in the world's oceans was already salty. That is why the Ancient Greeks called it “halite”, which means “sea”, “salt”.

The chemical formula of halite is NaCl, contains 60.6% chlorine and 39.4% sodium. A pure mineral is transparent, opaque or translucent, colorless or white with a glassy sheen. Depending on additional impurities, it may have shades: with iron oxide - yellow and red tones, organic inclusions - colors from brown to black, clay impurities - gray shades. An interesting blue and lilac color is given to halite by an admixture of sylvite (potassium chloride).

Halite is a brittle mineral with hygroscopic properties and a salty taste. It easily dissolves in water, melts at temperatures above 800°C, and colors the fire yellow. When mined, it is released in the form of cubic crystals or stalactites with a granular and spar-like structure. It has a conchoidal fracture, perfect cleavage, and is found in the rock with borates and sulfates formed during the evaporation of salt waters.

Products made from halite are sensitive to moisture and are short-lived due to their natural fragility. To maintain their original appearance, they must be wiped with alcohol, high-quality gasoline, or rinsed in a strong salt mixture, and then polished with a velvet cloth.

Varieties of halite

Depending on the physical properties and origin, halite is divided into the following categories:

• Rock salt is formed during the compaction of sedimentary deposits of halite formed in past geological eras. Occurs in the form of large massifs in layers of rocks;
• Self-sedimented salt is a rock formed in evaporite deposits in the form of druses and fine-grained deposits;
• Volcanic halite is asbestos-type aggregates formed during the vulcanization process. They are mined in places where lavas pass and where craters are located;
• Salt marsh is a salt efflorescence that forms in steppe and desert areas on the soil surface in the form of crusts and deposits.

Mineral deposits

Large deposits of halite were formed hundreds of millions of years ago in North America and Eurasia during the Permian period, when these areas were characterized by a hot and dry climate.

Nowadays, rock salt is mined in large quantities in Russia - in the Solikamsk and Sol-Iletsk deposits of the Urals, the Usolye-Siberian basin, located in the vicinity of Irkutsk, the regions of Iletsk Orenburg region, Solvychegodsk field Arkhangelsk region, as well as the Verkhnekamsk region, located in the vicinity of Perm. Self-sedimented halite is mined in the Lower Volga region and coastal areas of Lake Baskunchak Astrakhan region.

In Ukraine, rock salt deposits are located in Artemovsk, Donetsk region and Transcarpathia. Lake Sivash in Crimea is famous for its self-planted rocks. Unusually beautiful, large crystals are mined in Poland - Inowroclaw, Bochnia and Wieliczka. Halite of blue and lilac shades is found in deposits in Germany located near Bernburg and Strasbourg.

Large quantities of halite are mined in the American states of New Mexico, Louisiana, Texas, Kansas, California and Oklahoma. In India, development is taking place along the Himalayan mountain range in the state of Punjab. Salt of lake origin is also formed in the Iranian Urmia deposit.

The magical properties of halite

Widespread and simple in composition, halite, at first glance, does not have a supernatural purpose, but the magical potential, prayed for by people for many centuries, helps to increase good and fight evil.

There are many signs and sayings associated with salt that were formed by peoples different countries based on observations. It was believed that a handful of halite, sprinkled on the ground in the form of a cross, protects against evil spirits. On the other hand, spilled salt was perceived by many people as a signal of impending trouble and disease. The Slavs, when going on a campaign or to war, always took with them a handful of earth mixed with salt to protect themselves from mortal wounds.

To this day, magicians and sorcerers use halite in occult rituals. Halite increases good intentions many times over, but the mineral will return evil and envy like a boomerang in multiplied quantities. Spells with halite for good luck, love and happiness are effective, but for them to work you need to carry talismans with you. A pinch of crushed salt is sewn into children's clothes to protect them from damage and the evil eye. A mineral amulet protects its owner from emergencies, natural Disasters and violent actions.

Halite, as a talisman, does not like extraneous energy and, when exposed to public display, can absorb someone else's negativity. To prevent this from happening, it is necessary to keep secret the composition of the talisman or amulet and hide it from prying eyes.

Medicinal properties

Halite has unique antiseptic properties and is an effective method for treating colds and viral diseases. They are used to gargle at the first symptoms of sore throat, laryngitis or tonsillitis, as well as infections. oral cavity. Halite salt (1 tablespoon), diluted in a glass warm water, relieves toothache.

To treat diseases of the lungs and bronchi, air saturated with halite ions is used. In hospitals and sanatoriums, salt rooms are set up for this purpose, and at home you can improve your health with the help of a salt lamp.

Application

Halite is used in many industries. In the food industry, it is used as an essential nutritional element - salt, which is included in the diet of every person. Up to 7 million tons of mineral are spent annually for these needs.

The chemical industry uses halite to release chlorine and sodium, from which soda, concentrated alkaline compounds and hydrochloric acid are subsequently made. Halite is present in household detergents, paper and glass. Monocrystalline halite film is used in high-quality optics on lenses as an additional layer.

Using pressed technical halite, scale is removed from boilers and water heating elements are cleaned. The mineral concentrate is considered effective means in the fight against icing. The freezing point of halite is lower than that of water, which allows the formation of an ice crust to reduce its density and adhesion to the road surface. The mineral is used in construction and exploration work in frozen areas to thaw the soil.

The mineral druses are exhibited in collections and are also used to make crafts, jewelry, talismans and amulets. It produces amazing interior items - cylinders, pyramids and balls with natural shapes and soft colors. Halite is capricious and requires proper care, so it is rarely used in jewelry.

Agate - properties of the stone Moon rock(Adularia) and its properties Marble: properties and types of stone

How did reserves form in the earth? table salt? Why are thick layers of rock salt found in rock layers?

We know that salt is deposited in isolated areas of the earth's surface, which have a limited connection with the sea, where new portions of sea water constantly or periodically enter and where, thanks to the dry climate, and therefore strong evaporation, the brine becomes more and more saturated.

Where these areas of the surface gradually sank, thanks to tectonic movements the earth's crust, and thick deposits of table salt formed.

But how did the salt get into the sea? Why are rock salt deposits located either deep in rocks, or protrude to the surface of the earth, or sometimes form so-called salt domes?

To answer these questions, we must first tell you a little about the geological past of our Earth.

Since its inception, the globe has gradually changed its face.

Apparently, billions of years ago our planet was surrounded by a thick, impenetrable curtain of water vapor. They gradually cooled, thickened into clouds and fell to the ground in showers. Water filled the depressions of the earth, forming seas and lagoons. Rainwater, streams from mountain ranges and erupted hot water flowed into them.

“One must think,” wrote academician V. A. Obruchev, “that the water of the primeval sea was already salty, since among the gases released from the magma there were components of various salts.”

Chemical compounds that were washed out of rocks and were in the atmosphere were carried along with water in dissolved form. Apparently, table salt ended up in the primordial ocean. According to academician A.E. Fersman, “This is where the story of her wanderings above the earth, underground and in the earth itself begins.”

Water that has entered its constant circulation on the surface globe, throughout the subsequent geological history the earth brought more and more reserves of salts to the seas and oceans.

According to geologists, rivers still annually bring 2,735 million tons of various salts to the seas from land. Of this, 157 million tons are sodium chloride. From this alone one can judge how large the reserves of salt dissolved in the ocean are.

The distribution of continents and oceans on the Earth's surface has changed more than once. This happened during mountain-building processes and from extremely slow fluctuations of the earth's crust, which are observed in our time. The earth's crust in different places either slowly sinks, and then sea water floods the land, or rises, and then the sea recedes and the seabed is exposed.

From the geological past of our Motherland, it is known that more than two hundred million years ago, during the so-called Permian period of the Earth’s history, the waters of the ancient Perm Sea spilled over the vast surface of the European part of Russia, reaching a million square kilometers. It extended from the shores of the Arctic Ocean to the Caspian Lowland.

This sea existed for fifty million years. It covered the entire east of the European part of the country. Some of its bays and tongues in the north reached right under Arkhangelsk. In the south, long branches extended to the Donetsk basin and Kharkov. In the southeast it went far to the south.

Over the course of hundreds of thousands of years, this sea has changed its shape. It then retreated, then again flooded a huge expanse of land. This huge sea gradually shallowed, forming separate lakes along the shores. Humid climate was replaced by the winds and sun of the desert.

“The young Ural ranges were destroyed by powerful hot winds - everything was blown to the shores of the dying Perm Sea. The sea was moving south. In the north, gypsum and table salt accumulated in lakes and estuaries,” wrote A.E. Fersman. And in the southeast of our country, the Black Sea was then connected with the Caspian Sea, then separated, until, finally, they were finally separated from each other by the last rise of the Caucasus Mountains.

The barren, sandy desert with scattered salt lakes between the Caspian and Aral seas was also once the seabed. The desert soil is still saturated with salt, and it contains many sea shells that once lived in an ancient, disappeared sea.

And in those areas where there were estuaries and bays that had a limited connection with the sea, where there was a dry climate and where the earth’s crust subsided, we now find deposits of rock salt.

As is known, the formation of the earth's crust did not always occur calmly. The gigantic force of underground pressure more than once crushed the earth's crust into folds. Mountain ranges bulged, dips and subsidence occurred. During these displacements of rock layers, layers of sedimentary rocks deposited at the bottom sometimes came to the surface of the earth former seas. Layers of rock salt also came to the surface, while in other places the salt remained buried at great depths.

Let's take a look at the expanses of the CIS. The Volga region, the Urals and Central Asia are famous for their richest salt deposits. Rock salt deposits stretch between the Urals and Emba, from Solikamsk all the way to the Caspian steppes over six thousand square kilometers with a thickness of 450-500 meters. Ukraine is also rich in this regard - salt layers lie in the Donetsk depression, forming large accumulations in the area of ​​​​Artemovsk and Slavyansk.

Due to the difference in vertical pressures in the earth's layers, due to the plasticity of salt, so-called “salt domes” were formed - powerful salt deposits. Salt is so plastic that under pressure it flows like resin and forms rods and domes several kilometers high. In the Caspian region, in Ukraine and in the lower reaches of the Khatanga River there are over a thousand salt domes that formed during the formation of the Ural Mountains.

But underground rock salt deposits are not the only sources of table salt.

A huge number of salt lakes and lagoons - remnants of dried up or once gone seas - also serve as rich salt storage facilities. Here, in evaporating estuaries and lakes, crystals of sodium chloride, falling out of solution, settle to the bottom and over time form layers of salt.

In desert and semi-desert areas, lagoons, cut off from the sea, sometimes turn into a kind of natural “chemical laboratories” under the scorching rays of the sun. Transformations of various substances occur in them and various salts are formed, including sodium chloride.

One of the most majestic natural “laboratories” is the bay of the Caspian Sea - Kara-Bogaz-Gol.

This bay is separated from the sea by a long spit, and only a narrow strait still connects it to the sea. Not a single river flows into Kara-Bogaz. All around lies the waterless steppe. The dry steppe wind and scorching sun quickly evaporate the waters, and if water from the sea had not flowed into the bay, Kara-Bogaz would have dried up long ago. Its water is not like ordinary sea water. It's thick brine, in which the concentration of salts is twenty-four times greater than in the Caspian Sea. It has been established that into the bay along with sea ​​water Hundreds of millions of tons of various salts are introduced annually, but the water from the bay quickly evaporates, and thus a thick brine is obtained, from which mainly mirabilite (Glauber's salt) and halite (table salt) fall out in the form of crystals to the bottom of the bay. Huge reserves of mirabilite made Kara-Bogaz-Gola famous as a deposit of world significance. In addition to mirabilite and table salt, magnesium sulfate, magnesium chloride and other salts are also produced here.

There are many salt lakes connected to the sea in Crimea and Moldova. Some of them have not yet completely separated from the sea, others are separated from the sea only by a narrow spit.

Crimean salt lakes are distinguished not only by the richness and diversity of salts, but also by the inexhaustibility of their salt reserves. These are, in the full sense of the word, “inexhaustible” sources of table salt. Most of them owe their origin to the sea, from which they were gradually separated by spits and embankments.

Strong evaporation of water led to the fact that the water level in the lakes dropped significantly compared to sea level and the brine in them thickened. But the sea continues to enrich these lakes with salt, as sea water seeps through sand spits and embankments and enters the lakes.

However, not all salt lakes separated from the sea. Many lakes arose differently. They were never connected with the sea and are therefore called continental. Thus, in the Caspian steppes there are many deep depressions into which spring streams rush and rainwater accumulates. And since the soil in these areas is saturated with salt, the flowing water erodes this salt, dissolves it, and the lake becomes salty. This is how the Central Asian, Transbaikal and Siberian salt lakes were formed.

Among the steppes and deserts, salt lakes stand out sharply with their whiteness. Salt crystals shimmer like a multi-colored rainbow from the rays of the sun.

The layer of salt deposits in some lakes reaches several tens of meters in thickness. This applies primarily to lakes that are connected by their feeding with deep salt deposits, for example, Elton, Baskunchak, Inder.

The largest lake from which table salt is now extracted in Russia is Baskunchak. It appears to be connected to the salt domes located in the depths. Some lakes are constantly fed by salt, which comes into them from the soil surrounding the desert. That is why their salt wealth is so great and inexhaustible. This assumption is confirmed by the example of some small lakes, the salt reserves of which are sometimes depleted after several years of development. However, some time passes, and the waters of the lake are again saturated with salt. Apparently, salt is dissolved in the soil by rainwater, and therefore these lakes are indeed fed by salt from the surrounding salt desert.

There are many salt marshes in the southern dry countries. Here, the scorching sun heats the soil up to 70-79 degrees in summer, and the slightest reserves of soil moisture evaporate; with strong evaporation, salty groundwater rises through capillaries in the sand. Water evaporates and salts are deposited in the upper layers of the soil. This is how salt marshes are formed where subsoil salty water is located at a depth of 1-2 meters.

In ancient times, farmers could not fight against soil salinization. Poor maintenance and excessive watering caused the level of salty groundwater to rise, and with strong evaporation, salinization was caused. Therefore, many lands in Central Asia have turned into areas of so-called secondary salt marshes.

The third source of salt is mineral water, emerging to the surface of the earth from its depths.

Flowing underground among various rocks, water dissolves easily soluble salts in them and again draws them into the cycles of underground and above-ground wanderings.

These wanderings of salts are complex and confusing. They travel from the ocean to land and into the atmosphere, from there to rivers and further back to the ocean; and the second way: from underground sedimentary strata - to the surface of the earth and again deep into the earth...

But that's not all.

Fine salty dust swept away by the winds from the surface of dry salt marshes, the smallest wind-blown droplets of sea water, eruptions active volcanoes, evaporation of salt lakes - all this contributes to the salt cycle on the surface of the planet.

Humans, animals and plants, by absorbing the salt they need, also participate in this cycle.

Salt comes in different tastes, sizes, shapes, colors and degrees of salinity. It all really depends on where she comes from. It is impossible to cover all the many types of salt, but the editor of the “Food” section The Village Anna Maslovskaya decided to understand the issue and classify the main ones.

Origin

Sea salt is extracted from sun-concentrated brine that forms in areas where salt water floods. It is scraped off, dried, and sometimes recrystallized. Another way to obtain sea salt is by freezing. Not evaporation of water, but placing sea water in the cold.

Sad salt is obtained in a similar way to sea salt: by evaporating water from underground salt springs or by evaporating water in salt marshes. In these places, salt water stagnates on the surface of the earth, but does not come from the sea, but from other sources.

Rock salt, also known as mineral salt, is mined in mines. It is formed due to the flow of saline sources or, for example, on site dried up seas. Until recently, along with boiled sea salt, mineral salt was the most popular in the world.

Salt, depending on the method of its extraction, is then either ground or sifted. Thus, they divide it by caliber: from small to large.

Fine table salt

It's table salt. As a rule, it is of stone or cage origin. The second option is considered the cleanest. It is obtained by repeated recrystallization of brine and, apart from salt, contains little in itself - white table salt has a purity of at least 97%. While stone can contain a significant amount of impurities that affect the taste. When sifting it, you can find microscopic pieces of clay and stones. Russia has the most big places the production of table salt is Lake Baskunchak in the Astrakhan region and Lake Elton in the Volgograd region.

Table salt has the purest salty taste, this is both its advantage and disadvantage. The main advantage is that it allows you to accurately dose the amount during preparation. The downside is that its taste is flat and one-dimensional. Table salt is one of the cheapest types of salt, along with mineral salt.

Kosher salt

A special case of ordinary table salt. It differs in that the size of its granules is larger than that of ordinary salt, and the shape of the crystals is different. Not cubes, but granules, flat or pyramidal in shape, obtained thanks to special process evaporation. The shape makes it easier to feel the amount of salt with your fingers, which is why in America, where it is produced in large quantities, it has become an industry standard in professional kitchens. The taste is almost no different from ordinary table salt, but there is a nuance: it is never iodized.

Salt is called kosher because it is used for koshering meat, that is, rubbing the carcass to remove residual blood.

Rock salt

Iranian blue salt

Table edible rock salt, grind No. 1

This is a large family, most often the name of which refers to white table salt mined in a mine. For example, salt extracted from the Artyomovskoye deposit in Ukraine, the supply of which to Russia is now limited due to sanctions. As a rule, it is white, but sometimes has a slightly gray or yellowish tint. Salts with brighter impurities often acquire their own names. For example, black Himalayan salt, which will be discussed below. Rock salt is also used for technical purposes - for example, to salt a swimming pool or sprinkle a road.

Sea salt

Sea iodized salt from the Adriatic Sea

Hawaiian Sea Salt Black Lava

There are many types of it due to its origin. Since all seas have different chemical profiles, this is reflected in the taste and composition of the salt. Sometimes this salt is recrystallized to obtain pure table salt. Its value lies in the variety of tastes and the presence of additional impurities that enrich the taste.

Fleur de sel

Fleur de sel from Lake Reux

Swedish salt flakes

Flaked salt is highly valued by both chefs and ordinary consumers. Depending on its origin, it differs in shape, appearance, humidity and degree of salinity. Its traditional name is fleur de sel. Typically this is sea ​​salt, the crystals of which grow on the edges of salt baths, in the process of slow evaporation of water they become overgrown with beautiful growths, which, as a rule, are collected by hand at a certain stage of growth. That is, from the same source you can get both coarse salt and salt flakes.

Salt is mined in flake form in a variety of places around the world, but there are three best known deposits: salt from the French island of Reux, Maldon salt from the southeast of England, and salt mined from a large deposit in Portugal.

Maldon - very famous salt species fleur de sel, obtained in the Maldon area in the county of Essex in the south-east of England with late XIX century. It is correct to say “Maldon”, although “Maldon” has already taken root in Russia. Moldon salt - separately standing view salt, which differs from fleur de sel in that its crystals are larger, up to a centimeter. It is also slightly saltier than the classic fleur de sel. Being sea salt and having a shape in the form of flat crystals, it is delicate and creates a pleasant sensation, exploding on the tongue with salty sparkles. This makes Moldon salt a versatile finishing agent for dishes.

Black Himalayan salt

Pink Himalayan salt

Coarsely ground mineral salt, the color of which is due to the presence of impurities of potassium chloride and iron oxide. In total, salt contains about 5% of all kinds of impurities. It is used in hand mills to finish dishes, that is, not only for salting the dish, but also for decoration.

Pink Himalayan salt is mined in large blocks, which are then cut out, in the Punjab region, mainly in the troughs of the Himalayas, in Pakistan and India. Salt blocks are even used for interior work.

Pink Hawaiian salt

Sedimentary sea salt that was first collected in Hawaii. Now its main production takes place in California. The bright pink-brown color of medium-sized salt crystals is given by clay inclusions. Expensive product with a slightly iron taste. According to some reports, it is considered especially useful. But what you can’t argue with is that it’s beautiful, which makes it ideal for serving dishes.

Interesting fact

In foreign literature, the term “pink salt” refers to a special product based on salt with the addition of sodium nitrite, used for the production of meat products.

Flavored salts

Black Thursday salt

There are many types of aromatic salts, and all of them are invented and made by man. Such salt can be of any origin, the main thing in it is the combination of two functions: salting a dish with its flavoring. To do this, additives are placed in the salt or the necessary manipulations are performed on the salt itself, for example, smoking. Additives can be anything: flowers, spices, herbs, berries and even wine.

Thursday salt stands apart on this list because it is the result of rather complex manipulations. Initially, this salt was ritual (like pink Hawaiian salt), but now it is more often used because of its unusual taste. This salt is prepared as follows: table salt is mixed in equal proportions with leaven grounds or rye bread soaked in water; they put it in the oven (sometimes burying it in ashes), oven, or heat it in a frying pan. Afterwards, the monolithic piece is split and pounded in a mortar.

Interesting fact

Charcoal salt is used in many culinary traditions, such as in Japan and Korea. Just like the Thursday one, it is made by human hands. A similar example from Korea is bamboo salt: mOrsk salt is literally baked in bamboo.

Rock salt, or halite, is one of the most common minerals. Many people do not even realize that in its purified form this rock is nothing more than ordinary table salt. The mineral halite is something without which human life is impossible. Sodium chloride is a halogen. The name can also indicate the origin of the mineral. It consists of sodium and chlorine.

Rock salt, or halite, is one of the most common minerals

The use of halite is very common. Not a single housewife can do without salt. Ground sodium chloride is added to almost every dish. Without it, all food would be bland and would not acquire such shades of taste.

In addition, the mineral halite is widely used for canning and medicinal purposes. Sodium chloride has a pronounced antiseptic effect, which is very important in the presence of bacterial infections.

In its pure form, the breed is white or colorless. Depending on the number of additional inclusions, rock salt changes its color. If potassium is present, it turns blue. The formula of halite is NaCl. Many people are interested in how the rock is mined. The main location of the mineral is sea bays.

Depending on the number of additional inclusions, rock salt changes its color

Characteristics of the mineral

Rock salt comes in several varieties:

1. Sadochnaya - formed by granular crusts, usually in evaporite basins.
2. Stone - formed in large layers, found in rocks.
3. Volcanic is the most unusual type. Forms next to volcanic rock.
4. Efflorescences form on the soil surface and appear as thin crusts.

Few people know how this mineral is mined. In Russia a large number of halite is concentrated in the Urals. Rock salt is in great demand. It is used everywhere. A person consumes up to 4 kg per year. In addition to the food industry, rock salt is used in medicine, soap making, cosmetology and metallurgy. Almost no production can do without halite, which makes it so necessary.

How rock salt is produced (video)

Previously, the mineral was almost worth its weight in gold. The sedimentary rock is still very valuable today. The origin of the mineral may vary. Volcanic salt has long been considered a symbol of abundance. She was endowed with a lot of magical properties.

It was believed that if you spell salt and sprinkle it in front of the threshold, then not a single negative person will be able to enter the house. Halite has been used in various magical rituals, since it is endowed with special energy that can eliminate the evil eye, damage and other external influences.

Magical meaning has always been found in stones of this breed and used for healing. Salt was sprinkled on houses, sick people and things that were supposedly bewitched. To this day, many psychics use sodium chloride for rituals.

Gallery: rock salt (50 photos)

Additional Information

Halite stone was used to treat many diseases. Currently, salt is used to gargle. Special chemical composition has an antiseptic effect on the tonsils, freeing the lacunae from bacterial plaque, which is so important for sore throat.

Halite salt is mined all over the world. Deposits can be found almost everywhere, so at present this mineral is not in short supply. The use of rock salt is determined by its unique properties. It prevents the proliferation of viruses, bacteria and fungi.

Salt can leave the body through sweat, so when dehydration occurs as a result of vomiting or diarrhea, sodium chloride-based solutions are often prescribed, which promote fluid retention in the cells.

Any animal in wildlife always finds salt deposits and eats them. If there is not enough salt in the diet, then blood pressure and the conduction of nerve impulses are significantly reduced. At the same time, the heart muscle weakens, which is extremely dangerous.

Of course, an excess of this natural substance is also harmful, so people with arterial hypertension should use it with caution. Sea water contains a large amount of halite, so if you accidentally cut yourself on a shell while swimming, there will be virtually no pain. This is explained by the fact that the composition of rock salt, which is contained in sea ​​water, similar to blood chemical indicators.

The saline solution, which is used as a basis for infusion of drugs, contains a large amount of halite. It is used to eliminate the consequences of poisoning. After all, during intoxication, a significant amount of such an important compound as sodium chloride is lost.

If there is not enough salt in the human body, muscle spasms and cognitive behavioral disorders may occur. In addition, a significant lack of such a compound can be fatal. A diet that excludes salt provokes serious consequences if followed for more than 10 days.

How salt is mined (video)

An interesting fact about halite is associated with the defeat of Napoleon's army. The soldiers' diet lacked salt, so wounds healed extremely slowly. It has now been scientifically proven that a lack of sodium chloride can lead to long-term pathological processes of the skin, in which the integrity of the epidermis and dermis is damaged. Thus, this breed is valuable to this day.

Attention, TODAY only!

Several centuries ago, common salt was one of the most valuable commodities in world trade. In modern times, the relative value of salt has decreased markedly compared to other minerals. Oil, gas, and other resources filled the information space, and mentions of salt became quite rare. Meanwhile, in all spheres of human activity, salt continues to play a vital and difficult to replace role.

The meaning of salt

You may hear different names used for salt. The most commonly mentioned are rock salt and table salt. If we omit some nuances, which we will talk about below, then both rock and table salt are the same sodium chloride (NaCl). The importance of this chemical compound cannot be overestimated.

Naturally, first we should talk about rock or table salt as a food additive necessary for the human body. Normal activities human body without rock salt it is simply impossible. For example, gastric juice contains a significant amount of hydrochloric acid, and the main raw material for its production by the body is salt. Ions of various substances are involved in the transmission of impulses along nerve fibers and in the work of muscle tissue. This includes sodium ions, the main supplier of which is salt used in food. In addition, it contains, in the form of impurities, manganese, chromium, iron - trace elements that are absolutely necessary for humans.

As for industry, it is difficult to find an industry that is not directly or indirectly dependent on processed products obtained from ordinary salt itself. This is, for example, sodium metal, which is widely used in nuclear energy and aircraft manufacturing. It is impossible to do without salt in the production of soap and in the dyeing business. NaCl is also a raw material for the chemical industry. Chlorine, various sodas, caustic soda, hydrochloric acid - people get all this from rock salt.

Livestock farming, agriculture and municipal services, and the drilling industry will not be able to function without ordinary salt.

In percentage terms, the approximate distribution of all mined rock salt looks like this:

• most, about 60%, is consumed chemical industry as raw materials;
• approximately 25% is used in the food industry;
• the remaining 15% of consumption comes from utilities, Agriculture and other areas of activity.

World consumption of rock salt is growing every year. Over the past seven years, the growth in production, and, consequently, consumption, has amounted to 5%.

History of rock salt mining.

The history of rock salt mining goes back not even centuries - millennia!

The sea coast of modern Bulgaria - dome-shaped adobe ovens were discovered here, in which salt was evaporated. This saltworks dates back to the fourth millennium BC. Ancient sources contain references to salt mining in the 5th century BC. Salt mines dating back to the Bronze Age have been found by archaeologists in Austria.

Throughout all these millennia, the work of a salt miner has been exceptionally difficult. A wheelbarrow, a pickaxe and a shovel are the tools that were used to mine rock salt. And only at the beginning of the twentieth century mechanization came to the salt fields.

In Russia, the first mention of salt fishing dates back to the 11th century. At the end of the 17th - beginning of the 18th centuries, salt production in Russia developed very widely. By the 19th century, annual production of rock salt reached 350,000 tons. And by the beginning of the 20th century, more than 1.8 million tons were mined annually in our country.

Now the annual volume of world salt production is approximately 210,000,000 tons, and this volume is constantly growing. The growth of consumption predetermines the need to develop production technology and improve processing. Today there are several ways to industrially produce salt.

Basin method of salt extraction

Huge, practically inexhaustible reserves of salt are contained in the water of the seas, oceans, and salt lakes. This salt is mined using the pool or self-planting method. Natural estuaries are separated from the sea by dunes or spits. IN summer period, in hot weather, the water in the estuaries evaporates intensively, and salt precipitates. Where there are no natural estuaries, artificial pools are built. The pools are filled with sea water. After this, their connection with the sea is stopped, and the evaporation process occurs similarly to natural in estuaries, under the influence of the sun and wind. The precipitated salt is collected technologically. Equipment such as excavators, bulldozers, and, where necessary, hand shovels is used. This technology has remained unchanged for centuries. Mechanization only brought it to the modern industrial level. However, in the total volume of salt produced, this method takes only second place.

Mining fossil salt

In the first place is the extraction of fossil rock salt. Solid salt in the bowels of the Earth is otherwise called “halite”. Underground salt deposits formed hundreds of millions of years ago on the site of ancient seas and oceans. These rocks can be either colorless or snow-white. But more often, impurities color halite in different colors: clay impurities give it a gray color, iron oxides - yellow or red, the presence of bitumen - makes the rock brown.

Fossil salt development does not depend on the time of year and weather conditions, therefore, more than 60% of world production comes from them. Underground deposits of rock salt can reach depths of 7-8 kilometers, and reach the very surface, forming above-ground domes.

Deposits with a depth of up to one hundred meters are developed by open-pit or open-pit mining. Taking off upper layer soil and rocks covering salt deposits, you can begin to directly extract salt. The explosive, mechanical method or their combination is used. With the explosive method, holes are drilled in rock salt layers, explosives are placed, and by the force of the explosion, pieces of the salt layer break off from the main mass. IN mechanical method Special equipment is used to destroy the massif: excavators, graders, winches, etc. Open way mining ensures the most complete extraction of minerals, has the lowest cost and the greatest safety of work. The disadvantages of quarrying are that the mined rock salt is susceptible to contamination by sediments, groundwater, and dust deposits.

The deeper the quarry becomes, the less pronounced the advantages of this mining method become. Especially its profitability. At a certain stage, the profitability of quarrying becomes equal to the profitability of mining using the shaft method. Then, to improve the quality of the extracted salt, they switch to the latter.

When deposits are located at a depth of more than a hundred meters, the mine method is used to extract rock salt. At the moment, the single-horizon method of opening has displaced all others from salt mines. It does not require a large volume capital works, quite simple and universal. However, with significant deepening of workings, there is a need to organize multi-stage transport lifts and powerful ventilation systems.

A salt mine is a tunnel in the thickness of a salt layer. Chambers extend from it on the sides, from which the main selection of rock salt is made. Each chamber reaches a length of up to 500 meters. The width and height of the chambers are 30 meters each. The chamber system does not require securing excavations. The absence of the need to secure the roof reduces the cost of extracted salt and increases labor productivity. Large mined-out spaces in the chambers make it possible to use mining equipment with high productivity and power. Scraper installations, electric locomotives, road boring machines are widely used in salt mines. The exhausted chambers are successfully used for the safe disposal of industrial waste.

Along with the described advantages, the chamber system also has disadvantages. Large volumes of mined-out spaces lead to ventilation problems. In addition, more than half of the salt reserves remain in the spaces between the chambers (pillars), sometimes up to 70%.

It should be noted that most mining enterprises practice exclusively machine mining. However, in some cases a less advanced drilling and blasting method is used. Drilling pits, laying explosives and subsequent explosive rock fall give much less efficiency and productivity. At the same time, the level of labor safety is significantly lower.

Leaching mining method

The essence of this method is as follows:

• in the explored salt formation, wells of the required depth and in the required quantity are drilled;
• heated to high temperature fresh water;
• this water dissolves the salt;
• the liquid brine solution is pumped to the surface by slurry pumps;
• the salt slurry ends up in special sealed tanks with reduced pressure;
• thanks to low pressure intense evaporation of water occurs;
• The salt settled at the bottom of the tanks is crushed by a centrifuge.

Due to tank applications low blood pressure, this method is otherwise called vacuum. Its advantages include low cost, especially when extracting salt from great depths occurrence. To the disadvantages - high requirements to the chemical and mechanical resistance of pumps, due to the aggressiveness of the saline solution.

Explored world salt reserves and deposits

The world's reserves of rock salt are so huge that it is impossible to calculate their exact quantity.

Each cubic meter of water in the world's oceans contains about 27 kilograms of sodium chloride. If all the salt contained in the waters of lakes, seas and oceans is evenly distributed over the surface of the Earth, then the thickness of the salt layer will reach 45-50 meters.

Underground reserves of solid salt, according to the most rough estimates, are at least 3.5-4 * 1015 tons. If current production volumes are maintained, fossil reserves alone will last for at least fifteen thousand years.

In Europe, the largest salt deposits include the German Statfurt basin, the Slavyano-Artemovskoye and Prikarpatskoye deposits in Ukraine. IN North America there are large deposits in the USA (Kansas and Oklahoma), and the Canadian Saskatchewan basin.

On the territory of the Russian Federation there are reserves of table salt, the largest explored in the world.

In first place is Lake Baskunchak in the Astrakhan region. This unique deposit has been known since the 17th century. Its uniqueness lies in the fact that its salt reserves are replenished from the sources that feed the lake. According to geologists, the depth of the salt layers here reaches a record ten kilometers. On Lake Baskunchak, 930,000 tons of table salt are mined per year.

Nearby, in the Volgograd region, there is Lake Elton. There are also significant reserves of table salt.

The Sol-Iletskoye field has been developed in the Orenburg region for a long time. Back in the 18th century, the great Lomonosov examined samples of Iletsk salt. His notes have been preserved, in which he speaks extremely flatteringly about the quality of this salt. Here is located the Iletsksol JSC plant, the largest in Russia (83%) in terms of the volume of underground mining of fossil halites. According to the project, the annual production capacity of the Iletsksol plant is 2,000,000 tons. Salt from local deposits highest quality. It requires neither purification nor enrichment.

Another large deposit- Usolye, located in Yakutia, near Irkutsk.

In conclusion, I would like to add that there is definitely no threat of a shortage of rock salt to humanity.