How natural gas is formed in nature. Gas industry of Russia

Oil, natural gas and their derivatives— combustible minerals — are confined to basins composed of strata of sedimentary and volcanogenic-sedimentary rocks with diverse composition and structure.

Oil and gas bearing complexes, which are components of basins, are natural (material) systems in which the accumulation of hydrocarbons, and sometimes their generation, is possible. The main elements of the complexes are reservoir rocks that make up natural reservoirs, fluid-confining rocks, and oil and gas source rocks.

Oil and gas reservoirs- these are rocks that have the ability to contain mobile substances (water, oil, gas) and release them during operation.

Scheme 1 offers a general description of the types of reservoir rocks being studied.

For the formation of deposits, a necessary condition is the presence of weakly permeable rocks - fluid seals. which prevent the migration of oil and gas, which contributes to the accumulation and preservation of hydrocarbons entering the reservoir. Fluid seals. that cover the deposit are called tires.

The most important property of fluid seals is their shielding ability, which depends on a number of factors - power and endurance. mineral composition. structural, textural and tectonic features, etc.

The best tires, due to their increased plasticity (up to certain limits of temperature and pressure), are considered to be salt-bearing and clayey strata, the latter being the most common. In addition to them, other varieties of sedimentary and even igneous rocks that have a high density (rock strength) - cemented sandstones, layers of carbonate rocks, clayey shales, mudstones - may have shielding properties.

Depending on the mineral composition of the clays, their thickness, and age, the insulating ability will be different. The nature of the screening properties of clayey rocks is greatly influenced by the presence of impurities in them, as well as water and organic substances. The effectiveness of clay fluid seals is maintained within a certain range of depths, pressures and temperatures, and mechanical properties.

Table 1 shows the dependence of the screening ability of clays on parameters characterizing the filtering properties of rocks - changes in the structure of the pore space, permeability and gas breakthrough pressure.|

There are attempts to create a general classification of tires, which boils down to dividing them according to their material composition (clayey, chemogenic, etc.) and according to the breadth of their distribution (regional, basin-wide, zonal, local). The largest oil and gas deposits are usually located below regional seals, which reliably block the path of fluids. It is the tires that often determine the scale of accumulations and the stability of the existence of deposits.

Under natural reservoir understand a natural reservoir of oil, gas and water of a certain shape, throughout which fluid circulation occurs. Based on the fact that the shape of a natural reservoir is determined by the relationship between reservoir rocks and their host fluid seals. then three large groups were identified: stratified, massive and lithologically limited natural reservoirs.

Table 2 provides a brief description of the main types of natural reservoirs.

The main condition necessary for the formation of an oil and gas deposit is the presence of a trap. where the capture of hydrocarbons migrating (moving in the earth’s crust) in natural reservoirs occurs.

Trap- this is a part of a natural reservoir in which, as a result of screening fluids, the formation of their accumulation begins, and in the absence of movement of oil, gas and water, their relative equilibrium is established according to the law of gravity.

Under the influence of the gravitational factor, mobile substances are distributed in the trap according to their densities, i.e. oil and gas float in the water. The distribution of fluids in the trap is as follows: gas is concentrated in the roof part of the natural reservoir, directly under the fluid seal, the pore space below is filled with oil, and water occupies the lowest position. A trap is most often an area of a tank where conditions are stagnant, even if the rest of the tank has water in motion. When water moves, an oil-water separation is observed; sometimes all the oil can be displaced from the trap by water.

Depending on the reasons causing the occurrence of traps, the following most widespread types are distinguished: structural, stratigraphic and lithological. The last two types are called non-structural traps.

Most reservoir rocks are in the form of strata or layers that deviate from a horizontal position over any significant distances. The formation of a trap due to a change in the direction of the inclination of rock layers is usually caused by movements of the earth's rock: such traps are of the structural type. Hydrocarbons, migrating in reservoirs along the uplift of layers or perpendicular to their bedding along tectonic disturbances, fall into traps - arches of anticlinal structures, where industrial accumulations of oil and gas are formed. Accumulation of oil and gas in anticlines occurs due to the trapping of upward moving droplets of liquid and gas bubbles by an arch of folded layers. One specific type of anticline is a salt dome. They partially break through layers of sedimentary rocks, and the layers overlying them bend in the form of anticlines or domes. In addition to anticlines and salt domes, tectonically limited (screened) traps are a type of structural trap. A trap of this type is formed due to the fact that during shear (mutual movement of layers), permeable layers up the rise in the fault zone are screened by an impenetrable clay barrier, which effectively blocks the movement of oil up the inclined layer. Changes in permeability lead to the formation of stratigraphic traps.

When reservoir layers are replaced by impermeable rocks, a stratigraphic trap appears. The reasons why the permeability and porosity of the formation may change are changes in sedimentation conditions over the area, as well as the dissolving effect of formation waters. It is known that stratigraphic traps are formed during the cutting and erosion of a series of inclined strata, including porous and permeable ones, and their subsequent overlapping with poorly permeable cap rocks.

Lithological traps are formed due to the lithological variability of reservoir rocks, pinching out of sands and sandstones along the uplift of layers, changes in porosity and permeability of reservoirs, fracturing of rocks, etc.

Deposit- an accumulation of oil and gas in a trap, all parts of which are hydrodynamically connected.

Deposits usually form in places where highly porous sands were deposited following the deposition of silts enriched in organic matter. Fluids in the reservoir are usually under pressure approximately corresponding to hydrostatic pressure, i.e. equal to the pressure of the water column height from the surface of the earth to the roof of the deposit (10 kPa/m). Thus, the initial oil pressure at a depth of, for example, 1500 m can be 15,000 kPa. In the case of the appearance of reservoir properties of rocks, simultaneously with oil formation, traps appear along with the deposit.

The shape and size of the deposit are largely determined by the shape and size of the trap. The main parameter of a deposit is its reserves. There are geological and recoverable reserves. Geological reserves of oil and gas mean the amount of these in deposits.

A necessary condition for the occurrence of a deposit is the presence of a closed subhorizontal contour (trap boundary). A closed contour is considered as a line that limits the maximum possible area of a deposit in plan. The closed loop represents the limit below which hydrocarbons cannot be contained. An oil and (or) gas deposit can spread throughout the entire volume of the reservoir inside a closed loop or occupy part of it.

The deposits are mainly underlain by bottom water. If they contain oil and gas. then the deposits are divided into gas and oil. The following interfaces are distinguished: oil-water contact (OWC), gas-oil contact (GOC), gas-water contact (GWC). The accumulation of free gas above the oil in a reservoir is called a gas cap. A gas cap can only be present in a reservoir if the pressure in the reservoir is equal to the saturation pressure of oil with gas at a given temperature. If the reservoir pressure is higher than the saturation pressure, then all the gas will dissolve in the oil.

Figure 1 shows examples of images of oil and gas deposits on a map and geological section.

Oil and gas deposits are typified and classified according to various criteria.

According to the composition of fluids: pure oil, oil with a gas cap, oil and gas, gas with an oil rim. gas condensate, gas condensate - oil, pure gas, etc.

The ratios of oil, gas and water in deposits are shown in Table 3. Depending on the volume of oil and gas, the nature of saturation of the reservoir. geographical location, depth of drilling required to extract fluids and other indicators by which the profitability of development is assessed, deposits are divided into industrial and non-industrial.

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Oil and natural gas, like coal, are found in sedimentary rocks and are composed primarily of chemical compounds called hydrocarbons. The components of oil and gas that were among the first to form have high molecular weights, similar to the masses of the components of the solid material from which they originated, and are very viscous oils. As temperature and pressure increase, large molecules continually break down into lighter, more mobile ones. However, the elemental chemical composition of oil and natural gas did not change much and remained within a relatively narrow range of chemical mixtures (see table)

The energy equivalent of the estimated potential resources of oil is 1.5 10 22 J and gas 1.1 10 22 J (Data from the World Energy Conference).

A number of important conclusions can be drawn from the available knowledge of oil and gas resources.

Firstly, the resources of oil and gas, as well as coal, are distributed very unevenly around the globe.

Secondly, the regions that are now the main producers of oil and gas also have the greatest potential for new discoveries.

Thirdly, if the current rate of consumption growth continues, all oil and gas resources may run out in a few decades.

When oil is pumped out of a well, at least 60% of the original amount remains in the ground. Particularly thick oil is called heavy or more commonly called bitumen or tar. Many tars are so viscous that they can only be extracted using a shaft method with subsequent processing on the surface. Quite large deposits of tar sands have been discovered (Canada, USA, CIS, Venezuela). According to many experts, the potential of heavy oil and tar sands will be approximately equal to the potential of crude oil along with natural gas, but fundamentally new, more energy-intensive technologies for their production will be required.

The following oil and gas bearing regions can be distinguished on the territory of Ukraine:

Eastern (Dnieper-Donetsk depression and northwestern part of Donbass;

Western (Volyn-Podolsk plate, Carpathian region and Transcarpathia);

Southern (Black Sea region, Crimea and the boundaries of the exclusive (maritime) economic zones of the Black and Azov seas).

The state balance of Ukraine takes into account the reserves of oil, gas and gas condensate for 323 fields: 138,283 thousand tons of oil, 1,117,936 million m 3 of gas and 79,483 thousand tons of condensate. The main number of deposits (191 pieces) are located in the Eastern region, 9 – in the Western, 36 – in the Southern.

Annual hydrocarbon production in recent years has averaged 4 million tons. oil and condensate 18-20 billion m 3 of gas, which is approximately 10 and 20% of the country's needs, respectively.

An unresolved problem remains increasing oil recovery. In the fields of the Dnieper-Donetsk depression, the level of oil recovery reached only 30% against 45.5% of the design, and in the Cis-Carpathian trough 16.4 and 22.6%, respectively. The volume of residual geological oil reserves in Ukraine is more than 800 million tons. An increase in extraction by only 1% makes it possible to obtain an additional 8 million tons of oil. It should be noted that Ukraine owns huge volumes of unconventional sources of hydrocarbons. Thus, the volume of the mine method is 11 trillion. m 3, natural gas in the gas hydrates of the Black Sea is 7-10 trillion. m 3.

One of the fossil organic fuels is oil shale, the resources of which exceed even coal, although most of them are unlikely to be developed. If the organic material contained in all the world's shale were converted and used as fuel, such resources could provide at least 10 26 J of energy, and possibly more.

When processing shale, energy is used to extract and heat it. To process 1 ton of oil shale, it will be necessary to spend as much energy as is obtained by burning 40 liters. oil or equivalent amounts of gas, so conventional shale cannot be considered as a potential energy resource until new or improved ways of extracting energy from these rocks are found. Of undoubted interest are only those shale that, when processed 1 ton of raw materials, can produce more than 40 liters of oil equivalent.

Large deposits of such shale located in Estonia produce 320 liters. oil equivalent per 1 ton of raw materials.

The total potential resources of oil shale in the world are estimated at 650 trillion. t (26 trillion tons of shale resin). The main resources - about 430 - 450 trillion tons (24-25 trillion tons of shale resin) are concentrated in the USA (Colorado, Utah, Wyoming) and are associated with the Green River formation. There are large reserves of oil shale in Brazil and China, smaller ones in Bulgaria, Ukraine, Great Britain, Germany, France, Spain, Austria, Canada, Australia, Italy, Sweden, and in the territory of the former Yugoslavia.

In Ukraine, research to determine the geological structure and reserves of shale deposits continues. But also deposits like Boltinskoye (Kirovograd region) - 3.4 billion tons, Carpathian shale deposits (1500 billion) speak of the prospects for using this unconventional energy source. Huge shale reserves are available at the Yuzovskaya site (Kharkov and Donetsk regions).

Natural gas, which we are all so accustomed to in our kitchens, is a close relative of oil. It consists mostly of methane with admixtures of heavier hydrocarbons (ethane, propane, butane). Under natural conditions, it also often contains impurities of other gases (helium, nitrogen, hydrogen sulfide, carbon dioxide).

Typical composition of natural gas:

Hydrocarbons:

Methane – 70-98%
Ethane – 1-10%
Propane – up to 5%
Butane – up to 2%
Pentane – up to 1%
Hexane – up to 0.5%

Impurities:

Nitrogen – up to 15%
Helium – up to 5%
Carbon dioxide – up to 1%
Hydrogen sulfide – less than 0.1%

Natural gas is extremely widespread in the depths of the earth. It can be found in the thickness of the earth's crust at a depth of several centimeters to 8 kilometers. Just like oil, natural gas, in the process of migration in the earth's crust, falls into traps (permeable layers limited by impermeable rock layers), resulting in the formation of gas fields.

Five largest gas fields in Russia:

Urengoyskoe (gas)
Yamburgskoye (oil and gas condensate)
Bovanenkovskoe (oil and gas condensate)
Shtokmanovskoe (gas condensate)
Leningradskoe (gas)

Natural (hydrocarbon) gas is a frequent satellite of oil fields. It is usually found in oil in dissolved form, and in some cases accumulates in the upper part of fields, forming a so-called gas cap. For a long time, the gas released during oil production, called associated gas, was an undesirable part of the extraction process. Most often it was simply burned in torches.

Only over the past few decades has humanity learned to fully utilize all the benefits of natural gas. This delay in the development of this extremely valuable type of fuel is largely due to the fact that gas transportation and its use in industry and everyday life require a fairly high technical and technological level of development. In addition, natural gas, when mixed with air, forms an explosive mixture, which requires increased safety measures when using it.

Gas Application

Some attempts to use gas were made back in the 19th century. Lamp gas, as it was then called, served as a source of illumination. Gas fields were not yet being developed at that time, and gas produced along with oil was used for lighting. Therefore, such gas was often called petroleum gas. For example, Kazan was illuminated with such oil gas for a long time. It was also used to illuminate St. Petersburg and Moscow.

Currently, gas plays an increasingly significant role in the world's energy sector. The range of its application is very wide. It is used in industry, in everyday life, in boiler houses, thermal power plants, as motor fuel for cars and as a feedstock in the chemical industry.

Gas is considered a relatively clean fuel. When gas is burned, only carbon dioxide and water are produced. At the same time, carbon dioxide emissions are almost two times less than when burning coal and 1.3 times less than when burning oil. Not to mention the fact that when oil and coal are burned, soot and ash remain. Due to the fact that gas is the most environmentally friendly of all fossil fuels, it occupies a dominant position in the energy sector of modern megacities.

How gas is produced

Just like oil, natural gas is produced using wells that are distributed evenly throughout the entire area of the gas field. Production occurs due to the difference in pressure in the gas-bearing formation and on the surface. Under the influence of reservoir pressure, gas is pushed through the wells to the surface, where it enters the collection system. Next, the gas is supplied to a complex gas treatment plant, where it is purified from impurities. If the amount of impurities in the produced gas is insignificant, then it can be immediately sent to a gas processing plant, bypassing the complex treatment plant.

How is gas transported?

Gas is transported primarily through pipelines. The main volumes of gas are transported by main gas pipelines, where gas pressure can reach 118 atm. Gas reaches consumers through distribution and in-house gas pipelines. First, the gas passes through a gas distribution station, where its pressure is reduced to 12 atm. It is then supplied through gas distribution pipelines to gas control points, where its pressure is again reduced, this time to 0.3 atm. After that, the gas reaches our kitchen through gas pipelines inside the house.

This entire huge gas distribution infrastructure is truly a big picture. Hundreds and hundreds of thousands of kilometers of gas pipelines, entangling almost the entire territory of Russia. If this entire web of gas pipelines is stretched into one line, then its length will be enough to reach from the Earth to the Moon and back. And this is only the Russian gas transportation system. If we talk about the entire global gas transportation infrastructure, then we will be talking about millions of kilometers of pipelines.

Since natural gas has neither odor nor color, in order to quickly detect gas leaks, it is artificially given an unpleasant odor. This process is called odorization and occurs at gas distribution stations. Sulfur-containing compounds, such as ethanethiol (EtSH), are usually used as odorants, that is, unpleasant-smelling substances.

Gas consumption is seasonal. In winter, its consumption increases, and in summer it decreases. To smooth out seasonal fluctuations in gas consumption, underground gas storage facilities (UGS) are being created near large industrial centers. These may be depleted gas fields, adapted for gas storage, or artificially created underground salt caves. In summer, excess transported gas is sent to underground gas storage facilities, and in winter, on the contrary, a possible lack of pipeline system capacity is compensated by taking gas from storage facilities.

In world practice, in addition to gas pipelines, natural gas is often transported in liquefied form through special vessels - gas carriers (methane carriers). In liquefied form, the volume of natural gas is reduced by 600 times, which is convenient not only for transportation, but also for storage. To liquefy the gas, it is cooled to its condensation temperature (-161.5 °C), causing it to turn into a liquid. It is transported in this chilled form. The main producers of liquefied natural gas are Qatar, Indonesia, Malaysia, Australia and Nigeria.

Prospects and trends

Due to its environmental friendliness and the constant improvement of equipment and technologies, both in the production and use of gas, this type of fuel is becoming increasingly popular. BP, for example, predicts faster growth in demand for gas compared to other types of fossil fuels.

The growing demand for gas leads to the search for new, often unconventional, sources of gas. Such sources may be:

Gas from coal seams
Shale gas
Gas hydrates

♦ Gas from coal seams Mining began only in the late 1980s. This was first done in the USA, where the commercial viability of this type of mining was proven. In Russia, Gazprom began testing this method in 2003, starting trial production of methane from coal seams in Kuzbass. Gas production from coal seams is also carried out in other countries - Australia, Canada and China.

♦ Shale gas. The shale revolution in gas production that occurred in the United States in the last decade has not left the front pages of periodicals. The development of horizontal drilling technology has made it possible to extract gas from low-permeability shale in volumes that cover the cost of its extraction. The phenomenon of rapid development of shale gas production in the United States is spurring other countries to develop this area. In addition to the United States, active work on shale gas production is underway in Canada. China also has significant potential for developing large-scale shale gas production.

♦ Gas hydrates. A significant part of natural gas is in a crystalline state in the form of so-called gas hydrates (methane hydrates). Large reserves of gas hydrates exist in the oceans and in permafrost zones of continents. Currently, estimated gas reserves in the form of gas hydrates exceed the combined reserves of oil, coal and conventional gas. The development of economically feasible technologies for the extraction of gas hydrates is being intensively pursued in Japan, the USA and some other countries. Japan, which is deprived of traditional gas reserves and is forced to purchase this type of resource at extremely high prices, pays particular attention to this topic.

Natural gas has a great future as a fuel and source of chemical elements. In the long term, it is considered as the main type of fuel that will be used during the transition of the world energy sector to cleaner, renewable resources.

The first mention of the use of gas in cooking dates back to the first century AD.

The first gas stove was installed in Persia. By order of the king, a palace kitchen was built at the site of the gas outlet. This is the first time that coal and wood have been replaced by volatile fuels. The inexpediency of using this fuel consisted only in wastefulness, because it is impossible to shut off a natural source once set on fire.

Gas was used more economically in Russia for street lighting. Only it was mined not from natural resources, but from coal. For this purpose, in St. Petersburg in 1835, a plant was specially built for the production of gas, called lighting gas, which reflects its purpose.

Obviously, the method of separating gas from solid fuel in closed tanks served as the prototype for Pavlov’s boiler, used as a heat gun by employees of the Ministry of Emergency Situations. This principle is used in the production of economical, environmentally friendly fireplace inserts.

The supply of lighting gas to the lanterns was carried out through pipelines, strongly reminiscent of the current centralized gas pipeline system.

History of natural gas use

The Dutch physician and chemist Van Helmont at the beginning of the 17th century in the laboratory managed to decompose air into two component parts, calling these parts gases.

By gas was meant a substance capable of spreading throughout the entire available volume. The word gas became widely known after the publication of the “Elementary Textbook of Chemistry” by the French chemist Lavoisier in 1789.

History in ancient times

ABOUT flammable gases has been known since ancient times. Burning gas torches were called “eternal fire”, they were worshiped, temples and sanctuaries were built next to them.

“Sacred fires” existed in many countries of the ancient world - in Iran, the Caucasus, North America, India, China, etc. Marco Polo also described the use of natural gas in China, where it was used for lighting, heating, and evaporation salt.

What is natural gas

Natural gas is considered a mixture of gases formed as a result of the decomposition of organic substances in the bowels of the Earth. Typically, natural gas is collected at depths of one to several kilometers, although there are wells deeper than 6 km.
Under standard conditions, this is a gaseous substance in the form of:

individual accumulations (gas deposits);
gas cap of oil and gas fields.

Russia, Iran, Turkmenistan, Azerbaijan, the Persian Gulf countries, and the USA have large reserves.

Use of natural gas

Practical use of flammable gas, began in the mid-19th century after the invention of the gas burner by the German chemist Robert Bunsen.

Bunsen burners operated on artificial “illuminating gas” obtained during the processing of coal or oil shale. Very quickly, gas burners illuminated the streets and residential buildings of many capitals and large cities around the world.

In the Russian Empire, gas burners appeared simultaneously with St. Petersburg in Lvov, Warsaw, Moscow, Odessa, Kharkov and Kyiv.

Some varieties of natural gas

A distinction is made between natural gas and “associated” or “petroleum” gas. The difference between them is the amount of heavy hydrocarbons they contain. In natural, heavy hydrocarbon (methane) makes up more than 80% of the total composition of gas, in “associated” gas – no more than 40%, and the rest is ethane, propane, butane, and others.

"Associated" gas is contained in oil reservoirs on top of the oil, forming a gas cap that collects in porous rock covered by shale.

Shale prevents gas from escaping. Sometimes during drilling operations, as a result of a sudden change in pressure, gas separates from the oil and may leak. The disadvantage of “associated” gas is the need to purify it from impurities, while natural gas does not need purification.

Approximate composition of natural gas

Gas from different fields may have different compositions.

On average, the content of the components is as follows:

methane 80-99%
ethane 0.5-0.4%
propane 0.2-1.5%
butane 0.1-1%
pentane 0-1%
noble gases (helium, argon) - hundredths and thousandths of a percent.

Deposits of flammable substances with a helium content of 5-8% are extremely rare. Helium is very valuable and has pronounced chemical passivity.

In its liquefied state, helium is used to cool nuclear reactors. High purity metals are smelted in a helium atmosphere. Natural gas is the only source of helium. The composition may include hydrogen sulfide, from which sulfur used in industry is obtained. Other substances can range from 2% to 13% of the total volume. Every fifth oil field is an oil and gas field, and often this field contains not associated, but natural gas, which has the same value as oil.

Gas industry of Russia

In pre-revolutionary Russia, natural gas was not used, although its presence was noted.

Only after the October Revolution of 1917 did the Soviet government set the task of using gas produced along with oil. Until the end of the 30s of the 20th century, Soviet Russia did not have an independent gas industry; it was an accompanying oil industry, and gas fields were discovered exclusively in the process of oil exploration and production.

Exploration of gas fields began in 1939 in the Saratov region: gas was found in 1940, and the first working well was installed in 1941.

The shortage of fuel that arose at the beginning of the Great Patriotic War of 1941-1945 (the coal fields of Donbass and the oil fields of the North Caucasus were temporarily “lost”) forced us to engage in exploration and production of natural gas with maximum intensity. Already in 1941, industrial production of natural gas began in the Saratov and Kuibyshev regions. The daily productivity of one gas well was 800 thousand.

cubic meters gas The exploitation of these fields marked the beginning of the gas industry. Initially, gas was used to operate the Saratov State District Power Plant, and in 1942, construction of the Saratov-Moscow gas pipeline began.

Construction was supervised by Lavrentiy Beria and was completed in July 1946. More than 30 thousand people worked on the gas pipeline every day. From Saratov to Moscow, 840 km of gas pipeline was manually laid through 487 barriers. Was built:

84 crossings of rivers and canals;
250 crossings over railway tracks;
six piston compressor stations;
More than 3.5 million cubic meters of soil were removed.

The gas pipeline passed through the territories of the Saratov, Penza, Tambov, Ryazan and Moscow regions.

For information

Feed 1 million

What is natural gas, what is its composition and how is it produced?

m of gas to Moscow replaced the daily consumption:

million cubic meters of firewood;
650 thousand tons of coal;
150 thousand tons of kerosene;
100 thousand tons of heating oil.

In the post-war period, large industrial deposits were discovered in the Stavropol Territory, in the north of Russia and in Siberia.

The importance of the gas industry in the Russian economy

The importance of the gas industry is determined, first of all, by the fact that in the structure of global fuel and energy consumption, natural gas ranks third after oil and coal - approximately 20%. It is also of great importance that of these three types of primary energy resources, natural gas is the cleanest in environmental terms.

Gas is the best type of fuel. It is distinguished by complete combustion without smoke and soot; absence of ash after combustion; ease of ignition and regulation of the combustion process; high efficiency of fuel-using installations; cost-effectiveness and ease of transportation to the consumer; possibility of storage in a compressed and liquefied state; absence of harmful substances.

The use of gas is varied: the main part is used for energy needs (fuel for thermal power plants, boiler houses); the other is used as technological fuel for drying various products (evaporation of aqueous solutions); for household consumption in public utilities.

Gas in liquefied or compressed form is used in internal combustion engines in cars, and it can be used in aircraft. The energy use of natural gas is determined by its high calorific value, simplicity of technological equipment for burning gas and minimal environmental pollution.

It is the most promising type of fuel in the world.

From the second half of the 20th century. Natural gas is widely used as a raw material for a number of industries.

The largest consumer of gas as a technological raw material has become the chemical industry, which focuses on nitrogen production.

The use of natural gas is the basis for the production of ammonia and all types of nitrogen fertilizers, methyl alcohol, the global production of which already reaches tens of millions of tons and continues to grow at a rapid pace. A significant amount of gas is used to make carbon black for rubber and many other chemicals.

Feed protein (feed yeast) is also produced from natural gas. It participates in the processes of direct reduction of iron (blastless production of metal), as well as in the blast furnace process when smelting cast iron.

Natural gas is also a source of chemical raw materials, including the production of gas sulfur from hydrogen sulfide from a number of deposits. Gas sulfur has significantly increased the total world resources of sulfur-containing raw materials.

Along with natural gas, helium, a noble gas, is extracted in some fields. It is widely used in cryogenic technology, for creating inert environments, as well as in aeronautics.

When developing gas condensate deposits of natural gas, gas condensate (a mixture of liquid hydrocarbons) is released - motor fuel and valuable raw materials for the production of organic chemical products. In this respect, it is close to associated gas from oil production. Some natural gas deposits contain pure nitrogen, which is also utilized in a number of industries. In addition, both natural and associated petroleum gas are injected back into oil reservoirs when necessary to maintain high pressure during oil production.

Associated petroleum gas, extracted during oil production, is also a high-calorie fuel, but is even more valuable as a raw material for the petrochemical and chemical industries.

It contains a lot of ethane, propane, butane, etc., which are used to produce plastics, synthetic rubbers and other products. Unlike targeted natural gas production, associated gas is often flared at oil production sites.

It requires separation into fractions at special gas processing plants (GPPs), the construction of which is either not planned or is delayed before the start of oil production.

The gas industry is a branch of the fuel industry, covering the exploration and exploitation of natural gas fields, long-distance gas supply through gas pipelines, the production of artificial gas from coal and shale, gas processing, its use in various industries and utilities.

The gas industry is one of the components of the fuel and energy complex (FEC), which includes enterprises for the extraction and processing of all types of fuel (fuel industry), electricity production and its transportation (electric power industry).

The development of the fuel industry, it would seem, is determined primarily by the available reserves of various types of fuel: after all, if they are not there, then there cannot be their production.

However, the reality is more complex. We owe the enormous size of Russia's territory to the fact that our country has large reserves of fuel, of all types. Therefore, the decisive criterion for field development is economic. It is necessary to decide which of the existing deposits is appropriate and most efficient to develop.

The role of individual types of fuel in the Russian economy has changed. At the beginning of the century, firewood was of great importance.

Then they gradually began to be replaced by coal (by the 50s, the coal industry provided more than half of all fuel). And later the growth of oil and gas began. In 1994, the total production of primary energy in Russia amounted to 1410 million tons of fuel equivalent. The share of gas, as the cheapest fuel, has grown rapidly in recent years (due to a reduction in oil and coal production).

Gas is used in large quantities as fuel in the metallurgical, glass, cement, ceramic, light and food industries, completely or partially replacing fuels such as coal, coke, fuel oil, or is a raw material in the chemical industry.

The largest consumer of gas in industry is the ferrous metallurgy. In blast furnaces, partial use of natural gas saves scarce coke by up to 15% (1 cubic meter).

m of natural gas replaces 0.9 - 1.3 kg of coke), increases furnace productivity, improves the quality of cast iron, and reduces its cost. In cupola furnaces, the use of gas reduces coke consumption by half.

The method of direct reduction of iron from ores is also based on the use of gas fuel.

In metallurgy and mechanical engineering, natural gas is also used to heat rolling, forging, thermal and smelting furnaces and dryers. In metalworking, the use of gas increased the efficiency of furnaces by almost 2 times, and the heating time of parts was reduced by 40%.

The use of gas in metallurgy, in addition, extends the service life of the lining. The amount of sulfur in cast iron is reduced.

The use of natural gas in the glass industry instead of generator gas increases the productivity of glass furnaces by 10–13% while reducing specific fuel consumption by 20–30%. The cost of cement is reduced by 20 - 25%.

In brick production, the cycle is reduced by 20%, and labor productivity increases by 40%.

When introducing natural gas in glass melting, special measures are required to bring the luminosity of the gas (that is, to increase the heat transfer from the torch to the glass melt) to the level of the luminosity of a liquid fuel torch, that is, 2–3 times, which is achieved by soot formation in a gaseous environment.

In the food industry, gas is used for drying food products, vegetables, fruits, baking bakery and confectionery products.

When using gas at power plants, operating costs associated with storage, preparation and losses of fuel and operation of the ash removal system are reduced, the overhaul mileage of boilers is increased, land for ash dumps is not occupied, electricity consumption for own needs is reduced, the number of operating personnel is reduced, and capital costs are reduced.

So, the products of the industry under consideration are provided by industry (about 45% of total economic consumption), thermal power generation (35%), and municipal household services (more than 10%). Gas is the most environmentally friendly fuel and a valuable raw material for the production of chemical products. Now let's look at the composition of the gas industry.

It includes the following elements:

— natural gas production; associated gas production;

— production of combustible gas from coal and shale; gas storage.

Associated gases cannot be directed into the main gas pipeline, because heavy hydrocarbons, when cooled or compressed, are released in the pipe in the form of a liquid, which, upon contact with moisture, forms a hydrate plug, reducing the cross-section of the gas pipeline or completely clogging it.

Therefore, these gases are sent to gas processing (gasoline) plants, where heavy hydrocarbons and other components are extracted from them, after which the stripped (dry) gas, consisting mainly of methane, is sent to consumers.

Gas consumption is not uniform throughout the year, decreasing in the summer months and increasing in the winter.

To smooth out uneven consumption and create emergency gas reserves for large consumers, for example in cities, special storage facilities were built - gas tanks, in which excess gas accumulated.

Gas tanks have a number of significant disadvantages - they are expensive, occupy large areas and are insufficient in volume.

The problem of gas accumulation in large quantities was solved when a method was developed to create underground gas storage facilities.

The gas industry is not a purely mono-product industry.

How is gas used?

Along with natural gas supplies through main pipelines, oil, condensate, sulfur, liquefied gases, engineering and agricultural products, etc. are produced. However, the basis of the industry, which ensures its competitive advantages, is the Unified Gas Supply System (UGSS), which combines the production and transportation of natural gas into a single technological, technical and economic system within Russia, connected with the gas supply systems of the Central Asian and Transcaucasian republics of the CIS and having its own continuation in Russian gas supply systems to three European CIS countries and twenty other European countries.

OJSC Gazprom is the largest gas company in the world.

The main activities are geological exploration, production, transportation, storage, processing and sales of gas and other hydrocarbons. The state is the owner of a controlling stake in Gazprom - 50.002%.

Gazprom sees its mission in the most efficient and balanced gas supply to consumers of the Russian Federation, fulfilling long-term gas export contracts with a high degree of reliability.

The strategic goal is to establish OAO Gazprom as a leader among global energy companies through the development of new markets, diversification of activities, and ensuring reliability of supplies.

Natural gas - composition and basic properties

Many of us are under the misconception that natural gas is a clear gas with a pungent odor that burns with a blue flame.

Natural gas. Properties, production, application and price of natural gas

It's time to dispel these misconceptions, learn more about the basic properties of natural gas and study its composition.

Composition of natural gas

We are accustomed to associate the concept of “natural gas” with methane, but it contains a whole mixture of gases and various impurities.

The so-called “wild” methane, which has just escaped from the thickness of the earth’s rocks, is a mixture of gases: methane (90-98%), carbon dioxide and nitrogen.

Also present in this stream may be propane, butane, hydrogen, ethane, hydrogen sulfide and helium.

Processing of natural gas, in addition to methane, makes it possible to extract a number of other products that are widely used in industry and in the economy: sulfur, propane and butane, fuel oil, diesel fuel, gasoline 92 and 95.

Physico-chemical characteristics of natural gas:

purified methane is odorless and tasteless, and the pungent odor that we feel when there is a gas leak is the result of odorization (aromatization) of methane before supply to the consumer;
spontaneously ignites at a temperature of 650-700 C;
It is almost 2 times lighter than air, therefore, in the event of a leak, it concentrates in the upper layers of the building.
The density of gas in its normal state is 0.68-0.85 kg/m3.
when the temperature drops to -160 degrees, it can be compressed up to 600 times (liquefied gas);
becomes explosive when mixed with air in a volume of 5-15%;
upon combustion, releases carbon dioxide and hydrogen;
capable of existing in a solid state in the form of gas-hydrate deposits.

Types of natural gas:

lean (the most common type, containing a sufficient proportion of methane and a small percentage of heavy hydrocarbons);

fatty (containing a significant amount of heavy hydrocarbons and elements of inorganic matter - nitrogen, argon, hydrogen sulfide, helium, carbon dioxide).

Areas of use:

Natural gas is a real treasure needed in many areas of human life, for example:

gas engines;
fuel for ground transport;
household needs (room heating and cooking);
weapons production;
fertilizer production;
creation of inert environments;
oil and mining industry;
plastic production.

Impact on the environment:

It would seem that natural gas is good for everyone, but it also has a “dark” side.

When burned, it releases a significant amount of carbon dioxide, thereby having a destructive effect on the Earth's ozone layer. Also, a substance called carbon dioxide accumulates in the atmosphere, another “side effect” of the gas combustion reaction, classified as a greenhouse gas. Consequently, the situation with the greenhouse effect that threatens us is also aggravated by the gas industry.

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FEDERAL RAILWAY TRANSPORT AGENCY

State Educational Institution

Higher Professional Education

Branch of Irkutsk State Transport University

Krasnoyarsk Institute of Railway Transport

Department of OPD

Abstract on the topic:

"Oil and natural gas"

Completed by: student gr. S-08-2

Golovko M. O.

Checked by: Urbaev A.O.

Krasnoyarsk 2010

Mining of oil and gas

Oil is a natural flammable oily liquid that consists of a mixture of hydrocarbons of a wide variety of structures. Oil and flammable gas are found in the bowels of the earth both together and separately.

Natural flammable gas consists of gaseous hydrocarbons - methane, ethane, propane. production refining oil gas

Oil and flammable gas accumulate in porous rocks called reservoirs. A good reservoir is a sandstone formation embedded in impermeable rocks, such as clays or shales, that prevent oil and gas from escaping from natural reservoirs. The most favorable conditions for the formation of oil and gas deposits occur when the sandstone layer is bent into a fold with the arch facing upward. In this case, the upper part of such a dome is filled with gas, below is oil, and even lower is water.

Scientists argue a lot about how oil and combustible gas deposits were formed. Some geologists - supporters of the hypothesis of inorganic origin - argue that oil and gas deposits were formed as a result of the seepage of carbon and hydrogen from the depths of the Earth, their combination in the form of hydrocarbons and accumulation in reservoir rocks.

Other geologists, the majority of them, believe that oil, like coal, arose from organic matter buried deep under marine sediments, where flammable liquids and gases were released from it. This is an organic hypothesis for the origin of oil and flammable gas. Both of these hypotheses explain part of the facts, but leave another part unanswered.

The complete development of the theory of the formation of oil and flammable gas still awaits future researchers.

Groups of oil and gas deposits, like deposits of fossil coal, form gas and oil basins. They are, as a rule, confined to troughs of the earth's crust in which sedimentary rocks occur; they contain layers of good reservoirs.

Our country has long known about the Caspian oil basin, the development of which began in the Baku region. In the 20s, the Volga-Ural basin was discovered, which was called the second Baku. In the 50s, the world's largest West Siberian oil and gas basin was discovered. Large pools, in addition, are known in other areas of the country - from the shores of the Arctic Ocean to the deserts of Central Asia. They are common both on continents and under the seabed. Oil, for example, is extracted from the bottom of the Caspian Sea.

Russia occupies one of the first places in the world in terms of oil and gas reserves. The great advantage of these minerals is the relative ease of their transportation. Through pipelines, oil and gas are transported thousands of kilometers to factories, factories and power plants, where they are used as fuel, as raw materials for the production of gasoline, kerosene, oils and for the chemical industry.

Mining of oil and gas. How wells are drilled

The history of oil production and refining is very interesting. Like many other sources of organic substances, it was known to many ancient peoples. Excavations on the banks of the Euphrates have established that 6000-4000 BC. e. oil was used as fuel. There is information that we used oil in the Caucasus 2000 years ago. The Arab historian Istarhi, who lived in the 10th century, testifies that since ancient times, instead of firewood, Baku residents burned earth soaked in oil. Oil has long been exported from Baku as a lighting material.

Drilling wells and industrial oil production began, however, much later. In the 50-60s of the XX century. Oil and gas have come to the fore among fossil fuels.

Oil and gas are easier and cheaper to produce than coal. Drilling is the main work in oil and gas production. Unlike, say, coal or iron ore, oil and gas do not need to be separated from the surrounding mass by machines or explosives, and they do not need to be lifted to the surface of the earth by conveyor belts or in trolleys. As soon as the well reaches the oil-bearing formation, the oil, compressed in the depths by the pressure of gases and groundwater, itself rushes upward with force.

As the oil flows to the surface, the pressure decreases and the remaining oil in the depths stops flowing upward. Then water begins to be injected through wells specially drilled around the oil field. Water puts pressure on oil and pushes it to the surface through the newly revived well. And then there comes a time when only water can no longer help. Then a pump is lowered into the oil well and oil begins to be pumped out of it.

Storage and transportation

Transporting oil and gas to refineries, chemical plants and power plants is very convenient. Oil is transported by rail and highways in tanks, and by sea and oceans in oil tankers. But in many cases, oil and gas can be transported to any distance through pipes.

Oil and gas pipelines - highways made of steel pipes laid shallow in the ground - stretch for tens of thousands of kilometers.

But storing oil and gas is more difficult than storing coal and ore.

To store oil and petroleum products obtained from it, such as gasoline, it is necessary to build special metal tanks. They look like giant tin cans. The walls of oil storage tanks are painted with silver aluminum paint, which reflects the sun's rays well, so that oil and petroleum products do not heat up. Gas storage requires sealed, gas-tight containers. To ensure that gas takes up as little space as possible during storage (and during transportation across seas and oceans), it is liquefied, cooled to a temperature of 160 ° C and below. Liquefied gas is stored in tanks made of durable aluminum alloys and special steel. The walls are made double, and between the walls they put some material that does not conduct heat well, so that the gas does not heat up.

But the largest gas storage facilities are more convenient and cheaper to build underground. The walls of underground gas storage facilities are impenetrable rock layers. To prevent these rocks from falling out and collapsing, they are concreted. There are several ways to store liquefied gases underground. In some cases, the storage is a cavity, a mine opening, located quite deep. In other cases - a pit, a pit, closed with a sealed metal lid, or, better said, a roof.

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