Application of gas in industry and economy. General information about natural gas

The bowels of the earth have created not only huge underground reservoirs of natural gas - its reserves are also stored in a more compact form. In cold regions and under the ocean floor, where hydrostatic pressure reaches 250 atmospheres, the gas combines with formation water and a solid substance is formed - gas hydrate. In small volumes there is a huge amount natural fuel, in bound form the gas decreases up to 220 times.

Origin of natural gas

Hundreds of millions of years ago, an ocean splashed on the site of today's continents. The dead inhabitants of the water element fell to the bottom and turned into silt. They could not decompose because there was no air to oxidize and no bacteria to cause decay. The movement of the earth's crust contributed to the immersion of these masses further and further into the depths. High blood pressure and temperature caused chemical reactions, in which the carbon of organic residues combined with hydrogen, and new substances were formed - hydrocarbons.

If the pressure and temperature were not very high, high molecular weight liquids were obtained, which eventually turned into oil. When these parameters reached large values, low molecular weight gases were formed.

The compounds were covered with sedimentary rocks and ended up deep below the surface of the earth. Geologists find these minerals at depths of one to six kilometers.

There is another theory of education natural gases. Some scientists believe that hydrocarbons as a result tectonic movements gradually rise to the top, where the pressure is not so great, and form large accumulations of oil and

Earth's rocks are not solid - they have small cracks and pores. Gaseous substances fill these voids, so natural gas is found not only in, but also in stones located on great depth.

Properties of natural gas

Natural gas is not an isolated substance – it is a mixture of different components, the main one of which is methane.

It is impossible to find two absolutely identical samples from different deposits: each of them has a different composition.

For its formation, different organic residues were used, and the conditions for the occurrence of chemical reactions were also not the same.

No scientist can give you the chemical formula of natural gas - he can only tell you the percentage composition of its constituent substances. Additional components besides methane are hydrocarbons:

• ethane;
• propane;
• butane;
• hydrogen;
• hydrogen sulfide;
• carbon dioxide;
• nitrogen;
• helium.

From chemical composition flow out and physical properties natural fuel. There are no exact parameters either, because they depend on percentage components:

• density – 0.68–0.85 kg/m3 in gaseous and 400 kg/m3 in liquid form;
• spontaneous combustion – at a temperature of 650 °C;
• specific heat combustion – 28–46 MJ/m³.

Because natural gas is almost twice as light as air, it rises. A person cannot suffocate when he finds himself at the bottom of a lowland. But there is another danger: if there is from 5 to 15% of the volume of natural gas in the air, the mixture becomes explosive.

Based on it, a gas fuel system used in cars has been developed. The octane number of natural gas used in engines is from 120 to 130.

The combustion of natural gas is a rather complex process in which chemical energy is converted into heat. Combustion can be complete or incomplete.

Need for cleaning

At first glance, there is nothing complicated in using gas. Lay pipes, drill a well - and the blue fuel, located in the depths under high pressure, will flow to the boilers and stoves. But it’s not that simple – natural gas contains impurities that can harm pipelines, appliances or human health.

Deep in the earth there is a lot of moisture, which can enter into chemical reactions or create condensation, and a large number of it interferes with the passage of gas. Hydrogen sulfide causes metal to rust, and equipment quickly becomes unusable. To remove harmful components from raw materials, special treatment stations are installed at the fields.

Delivery

Gas pipelines are many thousands of kilometers long; the initial energy of the flow is not enough to overcome such distances.

No matter how smooth the internal surfaces are, friction still arises, the gas loses speed and heats up.

There are other ways to transport gas, but so far pipelines are the most economical.

Smell of gas

Natural gas is odorless, so why do apartment residents immediately sense if there is a leak somewhere? For our safety, special odorants are added to blue fuel, the slightest presence of which is sensitive to the human sense of smell. Usually this role is played by mercaptans, which have such an unpleasant odor that it is impossible not to notice it.

Throughout its history, humanity warmed itself by burning different kinds fuel.

If you think like that, then life is generally dangerous)
I hope it will become popular soon alternative sources energy.. The Earth's reserves are not eternal - this should be remembered too, everything has its beginning and end.
But the greenhouse effect is an interesting thing in general - after all, some deny that this is the influence of anthropogenic factors, such as the activities of production facilities and stations. Personally, I don’t agree with them, yet humanity is making its contribution to the destruction of the planet every minute..

Naturally, natural gas has less impact on the planet when burned than the same wood or coal, but its harm and immediate danger should not be denied either. First of all, gas is a volatile substance and its unsuccessful storage or distribution can lead to terrible, detrimental consequences for both humans and the environment. All hope lies with scientists that they will soon find a solution to protect the Earth from slow death by preventing the greenhouse effect...

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 terms for gas formation is the presence temperature regime at twenty degrees and a pressure of about 0.101325 Pascal. It is worth noting that the presented mineral resource from a natural deposit is mined only in gaseous state- gas hydrates.

The main properties of natural gas are the absence of any odor and color. To detect a leak, substances such as odorants, which have a strong and characteristically unpleasant odor, can be added. 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 may come in handy during production building materials, for municipal and domestic needs, as well as as a unique raw material for obtaining 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 certain state 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. The importance of proper preparation 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 during the mixing process various types gases 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 New 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 scattered organic matter.

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.

What do we know about hydrocarbons? Well, maybe something from school curriculum in chemistry, and the word “methane” periodically flashing in the media... What do we know about natural gas, besides its explosive properties? What other uses of natural gas are there besides the well-known cooking and heating of residential buildings? What's new in the world of energy consumption and energy security?

Basic properties

Let's start with the fact that the well-known phrase about the smell of gas in an apartment or on the street is not entirely correct. The liquid that is supplied to our apartments for cooking or heating water has neither taste nor smell. What we sense is nothing more than a special additive necessary to detect gas leaks. This is a so-called odorant; it is added at specially equipped stations in the following proportions: 16 mg per thousand cubic meters of gas.

The main component of natural gas is, of course, methane. Its contents in gas mixture is about 89-95%, the remaining components are butane, propane, hydrogen sulfide and so-called impurities - dust and non-flammable components, oxygen and nitrogen. The percentage of methane content depends on the type of deposit.

The energy of natural gas released during the combustion of one cubic meter of fuel is called the calorific value. This value is one of the initial ones in all issues of designing gas facilities, and in different countries are taken as a basis different meanings. In Russia, calculations are carried out according to lower heat combustion, in Western countries such as France and Great Britain - at the highest level.

Speaking about the explosiveness of natural gas, it is worth mentioning such concepts as explosive limits and dangerous concentrations. The gas explodes when its concentration in the room is from 5 to 15% of the volume. If the concentration is lower, the gas does not burn; if the concentration is more than 15%, then the gas-air mixture burns with additional air supply. A dangerous concentration is usually called 1/5 of the lower explosive limit, that is, 1%.

Basics of types and uses of natural gas

Butane and propane have found their application as fuel for cars (liquefied gas). Propane is also used to refill lighters. Ethane is used extremely rarely as a fuel, since it is a raw material for the production of polyethylene. Acetylene is extremely flammable and is used in welding and cutting metals. We have already discussed the use of natural gas, or to be more precise, methane; it is used as a combustible fuel in stoves, water heaters and boilers.

Types of produced natural gas

Based on the type of gas produced, fields are divided into gas or associated. The main difference between them is the percentage of hydrocarbon content. In gas fields, the methane content is about 80-90%, in associated, or, as they are commonly called, “oil” fields, its content is no more than 50%. The remaining 50% is the oil separated from the gas. One of the biggest disadvantages of gas from associated fields is its mandatory purification from various impurities. The production of natural gas is also associated with the production of helium. Such deposits are quite rare; helium is considered the optimal gas for cooling nuclear reactors. Sulfur, released from hydrogen sulfides extracted as an impurity in natural gas, is also used for industrial purposes.

The main tool for natural gas extraction is the drilling rig. This is a four-legged tower about 20-30 meters high. A pipe with a drill at the end is suspended from it. This pipe increases as the depth of the well increases; during the drilling process, it is added to the well special liquid so that the destroyed rocks do not clog it.

This liquid is supplied using special pumps. Of course, the cost of natural gas includes the costs of operating and constructing gas production wells. From 40 to 60% of the cost is the cost of this.

How does gas come to us?

So, having left the production site, purified natural gas enters the first compressor station, or, as it is also called, the head station. It is most often located in close proximity to the deposit. There, with the help of gas installations high pressure enters the main gas pipelines. To maintain a given pressure, stations are installed on main gas pipelines. Since laying pipes with this pressure category inside cities is prohibited, before each big city a branch is installed. This, in turn, does not increase, but decreases blood pressure. Part of it is consumed by large gas consumers - industrial enterprises, factories, boiler houses. And the other part goes to the so-called hydraulic fracturing stations - There the pressure decreases again. Where is the use of natural gas most familiar and understandable to us? These are stove burners.

How long has he been with us?

The active use of natural gas dates back to the mid-19th century, after the invention gas burner. Moreover, its initial use is not entirely familiar to us now. At first it was used to illuminate streets.

In the Soviet Union, until the end of the 30s of the last century, an independent gas industry did not exist. Gas deposits were discovered by chance, only during oil exploration. The active use of natural gas began during the Great Patriotic War. Lack of fuel due to the loss of some coal and oil fields, gave a powerful impetus to the development of the gas industry. After the end of the war, the gas industry actively developed and gradually became one of the most energy efficient.

There is no alternative

Perhaps the best proof of the advantages of natural gas as the most convenient source of energy is Moscow's performance. Connecting gas made it possible to save daily one million cubic meters of firewood, 0.65 million tons of coal, 150 thousand tons of kerosene and almost the same amount. And all this was replaced by 1 million cubic meters. m of gas. This was followed by gradual gasification of the entire country and the search for new fields. Later, huge gas reserves were discovered in Siberia, which are still being exploited to this day.

Industrial use

The use of natural gas is not limited only to cooking - although indirectly, it is used to supply heat to residential buildings. Most large urban boiler houses in the European part of Russia use natural gas as the main fuel.

Natural gas is also increasingly used in the chemical industry as a raw material for the production of various organic substances. All large quantity automobile giants are developing cars based on alternative types fuels, including hydrogen and natural gas.

Only gas is to blame

From an environmental point of view, natural gas can be called one of the safest types of organic fuel. However, the connection of gas to many areas of human life and subsequent combustion has led to a manifold increase in the content in the atmosphere. Otherwise, this process is called the “greenhouse effect”. And this has an extremely negative impact on the climate of our planet. However, new technologies and production levels in Lately minimize the level of emissions into the atmosphere. Let us remind you that gas is one of the safest types of fuel.