Natural gas is a mixture of certain types of gas that form deep in the earth after the decomposition of sedimentary organic rocks. This is a mineral that must be extracted together with oil or as an independent substance.

Properties of natural gas

In its natural state, gas is presented in the form of separate accumulations. They are usually called gas deposits, which accumulate in the bowels of the earth like gas caps. Natural gas in some cases can be found in deep layers of the earth in a state of complete dissolution - this is oil or water. Standard conditions for gas formation are a temperature of twenty degrees and a pressure of about 0.101325 Pascal. It is worth noting that the presented mineral from a natural deposit is extracted only in a gaseous state - gas hydrates.

The main properties of natural gas are the absence of any odor and color. To detect a leak, you can add substances such as odorants that have a strong and characteristic bad smell. In most cases, the odorant is replaced with ethyl mercaptan. Natural gas is widely used as fuel at power plants, in ferrous and non-ferrous metallurgy, cement and glass industrial enterprises. It can be useful during the production of building materials, for municipal and domestic needs, and also as a unique raw material for the production of organic compounds during synthesis.

In what state is gas transported?

To significantly simplify the task of transporting and further storing gas, it must be liquefied. An additional condition is the cooling of natural gas if there is a constant high pressure. The properties of natural gas make it possible to transport it in conventional cylinders.

To transport gas in a cylinder, it must be divided, after which it will consist mostly of propane, but also include heavier hydrocarbons. This happens because methane and ethane cannot exist in liquid states, especially if the air is warm enough (18-20 degrees). When transporting natural gas, it is necessary to comply with all requirements and established standards. Otherwise, you may encounter explosive situations.

What is liquefied natural gas?

Liquefied gas is a specific state of natural gas that has been cooled by pressure. Liquefied natural gas is brought into this state so that it is easier to store and does not take up much space during transportation. Thus, it can be delivered to the end consumer. The density of gas is half that of gasoline. Depending on the composition, its boiling point can reach up to 160 degrees. The liquefaction rate or economic mode is up to 95 percent.

The gas that is in the wells must be carefully prepared for further transportation in order to bring it to enterprises. These can be chemical plants, boiler houses, as well as city gas networks. Importance proper preparation The problem lies in the fact that natural gas contains various impurities that cause certain difficulties during its transportation and use.

How gas is produced in Russia

Natural gas is formed by the mixing of various types of gas that are found in the earth's crust. The depth can reach almost 2-3 kilometers. Gas can appear as a result of high temperature conditions and pressure. But oxygen access to the mining site should be completely absent.

Natural gas production in the territory Russian Federation carried out today in the deepest well. It is located near the city of Novy Urengoy, where the well goes almost six kilometers deep. The gas in these depths is under strong and high pressure. Proper extraction of natural substances involves drilling wells. In places where there is gas, several wells are installed. Specialists try to drill evenly so that the formation pressures have the same distribution.

Chemical composition of natural gas

Gas, which is extracted from natural deposits, consists of hydrocarbon and non-hydrocarbon components. Natural gas is methane, which includes heavier homologues - ethane, propane and butane. In some cases, you can find a natural substance that contains pentane and hexane vapors. The hydrocarbon contained in the deposits is considered to be heavy. It can be formed exclusively during the formation of oil, as well as during the transformation of dispersed organic substances.

In addition to hydrocarbon components, natural gas contains impurities of carbon dioxide, nitrogen, hydrogen sulfide, helium and argon. In some cases, gas and oil fields contain liquid vapors.

Pure natural gas is colorless and odorless. To be able to detect a leak by smell, a small amount of substances that have a strong unpleasant odor (rotten cabbage, rotten hay, rotten eggs) (so-called odorants) is added to the gas. Most often, ethyl mercaptan is used as an odorant (16 g per 1000 cubic meters of natural gas).

To facilitate transportation and storage of natural gas, it is liquefied by cooling at elevated pressure.

Physical properties

Approximate physical characteristics (depending on the composition; with normal conditions, unless otherwise specified):

The property of a gas being in a solid state in the earth's crust

In science for a long time It was believed that accumulations of hydrocarbons with a molecular weight of more than 60 reside in the earth's crust in a liquid state, and lighter ones in a gaseous state. However, Russian scientists A. A. Trofim4uk, N. V. Chersky, F. A. Trebin, Yu. F. Makogon, V. G. Vasiliev discovered the property of natural gas under certain thermodynamic conditions to transform into a solid state in the earth’s crust and form gas hydrates deposits This phenomenon was recognized as a scientific discovery and entered into the State Register of Discoveries of the USSR under No. 75 with priority from 1961.

The gas turns into a solid state in the earth's crust, combining with formation water at hydrostatic pressures (up to 250 atm) and relatively low temperatures(up to 295°K). Gas hydrate deposits have an incomparably higher concentration of gas per unit volume of porous medium than in conventional gas fields, since one volume of water, when it passes into the hydrate state, binds up to 220 volumes of gas. Zones of gas hydrate deposits are concentrated mainly in areas of permafrost, as well as under the bottom of the World Ocean.

Natural gas fields

Huge deposits of natural gas are concentrated in the sedimentary shell of the earth's crust. According to the theory of the biogenic (organic) origin of oil, they are formed as a result of the decomposition of the remains of living organisms. Natural gas is believed to form in the sediment at higher temperatures and pressures than oil. Consistent with this is the fact that gas fields are often located deeper than oil fields.

Gas is extracted from the depths of the earth using wells. They try to place wells evenly throughout the entire territory of the field. This is done to ensure a uniform drop in reservoir pressure in the reservoir. Otherwise, gas flows between areas of the field, as well as premature watering of the deposit, are possible.

Gas comes out of the depths due to the fact that the formation is under pressure many times greater than atmospheric pressure. Thus, driving force is the pressure difference between the reservoir and the collection system.

See also: List of countries by gas production

The world's largest gas producers
A country
Extraction,
billion cubic meters 		Share of world
market (%) 		Extraction,
billion cubic meters 		Share of world
market (%)
Russian Federation 647 673,46 18
USA 619 667 18
Canada 158
Iran 152 170 5
Norway 110 143 4
China 98
Netherlands 89 77,67 2,1
Indonesia 82 88,1 2,4
Saudi Arabia 77 85,7 2,3
Algeria 68 171,3 5
Uzbekistan 65
Turkmenistan 66,2 1,8
Egypt 63
Great Britain 60
Malaysia 59 69,9 1,9
India 53
UAE 52
Mexico 50
Azerbaijan 41 1,1
Other countries 1440,17 38,4
World gas production 100 3646 100

Preparation of natural gas for transportation

Plant for the preparation of natural gas.

Gas coming from wells must be prepared for transportation to the end user - chemical plant, boiler house, thermal power plant, city gas networks. The need for gas preparation is caused by the presence in it, in addition to the target components (different components are target for different consumers), also impurities that cause difficulties during transportation or use. Thus, water vapor contained in gas, under certain conditions, can form hydrates or, condensing, accumulate in various places(for example, bending a pipeline), interfering with the flow of gas; Hydrogen sulfide causes severe corrosion of gas equipment (pipes, heat exchanger tanks, etc.). In addition to preparing the gas itself, it is also necessary to prepare the pipeline. Nitrogen units are widely used here, which are used to create an inert environment in the pipeline.

Gas is prepared according to various schemes. According to one of them, a plant is being built in the immediate vicinity of the deposit. comprehensive training gas plant (GPP), which purifies and dehydrates gas in absorption columns. This scheme has been implemented at the Urengoyskoye field.

If the gas contains large quantities helium or hydrogen sulfide, then the gas is processed at a gas processing plant, where helium and sulfur are separated. This scheme has been implemented, for example, at the Orenburg field.

Transportation of natural gas

Currently, the main mode of transport is pipeline. Gas under a pressure of 75 atm is pumped through pipes with a diameter of up to 1.4 m. As the gas moves through the pipeline, it loses potential energy, overcoming frictional forces both between the gas and the pipe wall, and between layers of gas, which is dissipated in the form of heat. Therefore, at certain intervals it is necessary to build compressor stations (CS), where the gas is pressed to 75 atm and cooled. The construction and maintenance of the pipeline is very expensive, but nevertheless it is the cheapest method of transporting gas over short and medium distances in terms of initial investments and organization.

Except pipeline transport Special gas tankers are widely used. These are special ships on which gas is transported in a liquefied state in specialized isothermal containers at temperatures from −160 to −150 °C. At the same time, the compression ratio reaches 600 times, depending on needs. Thus, to transport gas in this way, it is necessary to stretch a gas pipeline from the field to the nearest sea coast, build an onshore terminal, which is much cheaper than a conventional port, to liquefy the gas and pump it onto tankers, and the tankers themselves. The typical capacity of modern tankers is between 150,000 and 250,000 m³. This method of transportation is much more economical than the pipeline one, starting from distances to the liquefied gas consumer of more than 2000-3000 km, since the main cost is not transportation, but loading and unloading operations, but it requires higher initial investments in infrastructure than the pipeline method. Its advantages also include the fact that liquefied gas is much safer during transportation and storage than compressed gas.

In 2004, international gas supplies through pipelines amounted to 502 billion m³, liquefied gas - 178 billion m³.

There are also other gas transportation technologies, for example using railway tanks.

There were also projects for using airships or in a gas hydrate state, but these developments were not used for various reasons.

Ecology

IN environmentally natural gas is the cleanest type of fossil fuel. When it burns, a significantly smaller amount of harmful substances is formed compared to other types of fuel. However, the burning of huge quantities by humanity various types fuels, including natural gas, for last half century led to some slight increase in atmospheric carbon dioxide, which is a greenhouse gas. Some scientists on this basis conclude that there is a danger of greenhouse effect and as a consequence - climate warming. In this regard, in 1997, some countries signed the Kyoto Protocol to limit the greenhouse effect. As of March 26, 2009, the Protocol had been ratified by 181 countries (these countries collectively account for more than 61% of global emissions).

The next step was the implementation, in the spring of 2004, of an unspoken alternative global program for accelerated overcoming the consequences of the techno-ecological crisis. The basis of the program was the establishment of adequate pricing for energy resources based on their fuel calorie content. The price is determined based on the cost of energy received at final consumption per unit of measurement of the energy carrier. From August 2004 to August 2007, a ratio of $0.10 per kilowatt-hour was recommended and supported by regulators (average oil cost $68 per barrel). Since August 2007, the ratio has been revalued to $0.15 per kilowatt-hour (the average cost of oil is $102 per barrel). The financial and economic crisis has made its own adjustments, but this ratio will be restored by regulators. The lack of controllability in the gas market delays the establishment of adequate pricing. average cost gas at the specified ratio - $648 per 1000 m³.

Application

Bus powered by natural gas

Natural gas is widely used as a fuel in residential, private and apartment buildings for heating, water heating and cooking; as fuel for cars (gas fuel system of a car), boiler houses, thermal power plants, etc. Now it is used in the chemical industry as a feedstock for the production of various organic substances, for example, plastics. In the 19th century, natural gas was used in the first traffic lights and for lighting (gas lamps were used)

Notes

Links

  • Chemical composition of natural gas from various fields, its calorific value, density

Gas is the most environmentally friendly 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 coefficient useful action 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 low cost of gas production compared to the cost of production of other types of fuel - coal, peat, oil - also plays a significant role. If we take the cost of coal (in terms of 1 ton of standard fuel) as 100%, then the cost of gas will be only 10%.

Thanks to high consumer properties, low production and transportation costs, a wide range of applications in many areas of human activity, natural gas occupies a special place in the fuel, energy and raw material base. In this regard, the increase in its reserves and consumption is proceeding at a high pace.

The gas industry is the youngest branch of the fuel complex. Gas is used in national economy as a fuel in industry and in everyday life, as well as a raw material for the chemical industry. The national economy uses natural gas extracted from gas fields, gas produced as a by-product of oil, and artificial gas extracted during the gasification of shale from coal. In addition, gas obtained from production processes in some sectors of the metallurgical and oil refining industries is used.

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 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.

Chapter 2. Russia’s place in world natural gas reserves

Russia ranks 1st in the world in terms of gas reserves; 2nd place in annual production volumes; 2nd place in gas consumption and provides 21% of world trade in this type of fuel. About 75% of gas is used in the domestic market; gas provides 50% of the country's electricity. Thanks to the presence of a unique gas transportation system, Russia plays an important role in ensuring the transit of Central Asian gas to Europe and the CIS countries.

The Russian gas industry is a set of enterprises engaged in geological exploration on land and offshore, drilling production wells, production and processing of natural gas, gas condensate and oil, transport and distribution, underground storage etc. The following chain of operations occurs in the gas industry: geological exploration > production > storage > processing > transportation > distribution. The subject composition of the gas market includes gas producers, gas distribution organizations, gas sales companies and gas consumers. The structure of the Russian gas complex is shown in Figure 1.

Current state raw material base natural gas in Russia is characterized by high depletion of base fields. There is a tendency to increase the share of complex and hard-to-recover reserves. The problems of their development are associated with difficult natural and climatic conditions and the remoteness of future large gas production centers from established centers of gas industry development. The absence of a state program for the reproduction and rational use of the mineral resource base has an impact on Negative influence on the efficiency of geological exploration work. The leading position in gas production is occupied by OJSC Gazprom. The society has the world's richest natural gas reserves.

Rice. 1 – Structure of the Russian gas complex



Natural gas is a mineral of a group of sedimentary rocks, which is a mixture of gases. This resource arose as a result of the decomposition of organic matter in the bowels of the Earth. Environmentalists recognize natural gas as the cleanest type of fossil fuel.

Characteristics and types of natural gas

The characteristics of natural gas depend on its composition. It is 1.8 times lighter than air, the spontaneous combustion temperature is 650°C. Dry gas has a density from 0.68 kg/m3 to 0.85 kg/m3, and liquid gas has a density of 400 kg/m3. A mixture of gas and air from 5% to 15% of the volume is explosive. Specific heat combustion from 8-12 kW-h/m3. When using natural gas in internal combustion engines octane number equals from 120 to 130.

Most natural gas is a mixture of gaseous hydrocarbons. The main part is methane (CH 4 - up to 98%), as well as heavy hydrocarbons - ethane C 2 H 6, propane C 3 H 8, butane C 4 H 10. The composition also includes other non-carbon substances: hydrogen H2, hydrogen sulfide H2S, carbon dioxide CO2, nitrogen N2, helium He.

In its pure form, natural gas has neither color nor odor. To make it easier to determine the location of the leak, odorants, substances with an unpleasant odor, are mixed into it.

Types of natural gas:

  • liquefied (LPG);
  • swamp;
  • oil;
  • carbonic;
  • gas hydrates;
  • slate;
  • lighting;
  • coke;
  • compressed or compressed (CNG);
  • associated petroleum;
  • by tiers and sub-tiers of the earthen layer Cretaceous period, where it is mined today - Turonian, Cenomanian, Valanginian, Achimov.

Natural gas field

Basically, natural gas deposits are found in the sedimentary shell of the earth's crust. Russia owns huge reserves of natural gas (Urengoy field), in Europe - Norway, the Netherlands, and most countries Persian Gulf, Iran, Canada, USA, there are large deposits in Azerbaijan, Uzbekistan, Turkmenistan and Kazakhstan. Gas hydrates are present in huge quantities at great depths under the seabed, as well as underground.

Natural gas production

Before mining, exploration is first carried out - gravitational, magnetic, seismic or geochemical. However, the only reliable way to find out whether there is a gas reserve underneath you is to drill a well. Natural gas is found at a depth of one kilometer. In the bowels of the Earth, gas is found in microscopic pores, which are connected to each other by channels - cracks, through which high pressure this important resource penetrates the pores more low pressure until it is inside the wells. All this is carried out in accordance with Darcy's law - the filtration of gases and liquids in a porous medium. Gas comes out of the depths as a result of the fact that in wells it is under pressure, which is several times higher than atmospheric pressure.

Gas is extracted using wells, which are evenly distributed throughout the entire field area. This is done to ensure a uniform drop in reservoir pressure in the reservoir. The extracted gas is prepared for transportation. Gas is transported by pipelines, special gas tankers, and railway tanks.

Use of natural gas

Natural gas is used as a highly economical fuel for power plants, the cement and glass industries, ferrous and non-ferrous metallurgy, the production of building materials, and the production of various organic compounds. This important resource is used for municipal and domestic needs. An energy source for megacities, motor fuel, paint, glue, vinegar, ammonia - we have all this thanks to natural gas.

Gas is one of the most widely used minerals. It is used in many areas of human activity as fuel and allows you to perform tasks that were previously unattainable. Natural gas, like coal or oil, is extracted from the depths of the earth using special equipment. It was formed under the influence high temperature and pressure from the remains of organic matter of animal origin over thousands of years.

Quite heterogeneous, depending on the location and various external factors, it may include different quantities: nitrogen, ethane, butane, propane, hydrogen, hydrogen sulfide, etc.

How is gas used in the modern world?

Gas is mainly used as fuel for cars, thermal power plants, fuel for heating residential and warehouse premises, as well as for heating and cooking food. It is widely used in the chemical and fuel and energy industries. Due to its affordable price and absolute environmental friendliness (gas is considered the most harmless mineral fuel in nature), it is used for both domestic and industrial needs throughout the planet.

How is natural gas used in the chemical industry?

The use of natural gas in the chemical industry has made it possible to synthesize substances such as polyethylene, which previously did not exist in nature. In addition, it is used as a raw material to create a variety of organic substances: acids, alcohol, plastics, rubber, etc.

Natural gas itself is odorless and colorless. Because of this feature, it cannot be used in its pure form, since its leakage will be completely unnoticeable. To keep people safe, substances that have an unpleasant odor, such as ethyl mercaptan, are added to the gas.

How is natural gas transported and where is it used?

Natural from wells, after which it is purified from various impurities, flavoring is added and fed into the pipeline under a pressure of 75 atmospheres. It is pumped through the gas transmission system to distribution stations, from which it is sent to consumers under significantly lower pressure.

There is also a method for liquefying natural gas, which allows it to be transported using special tankers. Further use of such gas is no different from the previous option. At the port, gas is pumped out and supplied to the gas transportation system.