Perspective development of the largest industriesindustry is impossible without the most valuable raw materials and high quality energy carrier - natural gas. Its use not only automates many technological processes, but also significantly improves the living conditions of the population.
What is natural gas?
There is no single chemical formula for natural gas - in each field it has a composition with a different ratio of its constituent components.
Natural gas is a mixture of hydrocarbons, most of which is methane. The remaining components are: butane, propane, ethane, hydrogen, hydrogen sulfide, helium, nitrogen, carbon dioxide.
Natural gas is colorless and odorless.the presence in the air can not be determined without the help of special devices. The smell familiar to each person is given to gas by an artificial way (odorization). Through this process, it is possible to sense the presence of gas in the air and prevent life-threatening situations.
Origin
Concerning the origin of gas, there is no single theory, scientists adhere to two versions:
- Once upon a time the place of the continents was the ocean.While dying, living organisms accumulated in a space in which there was no air and bacteria triggering the decomposition process. Due to geological movements, the accumulated masses sank deeper and deeper into the bowels of the Earth, where under the influence of high pressure and temperature they entered into chemical reactions with hydrogen, forming hydrocarbons.
- The dynamics of the Earth contributes to the uplift of hydrocarbons at a great depth, where there is a lower level of pressure. As a result, gas or oil fields are formed.
Mining
Contrary to popular belief, natural gascan be underground not only in voids, the extraction of which does not require significant material and energy costs. Often, it is concentrated inside rocks with such a small porous structure that it cannot be seen by the human eye. The depth of the deposits may be small, but sometimes reaches several kilometers.
The process of gas extraction includes several stages:
- Geological work, as a result of which the locations of deposits are accurately determined.
- Drilling wells. It is carried out throughout the field, which is important for a uniform decrease in gas pressure in the reservoir. The maximum depth of the wells is 12 km.
- Production.The process is carried out due to the different level of pressure in the gas-bearing formation and the earth's surface. In the wells, gas tends to go out - to where pressure is less, immediately entering the collection system. In addition, the associated gas is produced, which is a by-product of oil production. It is also valuable for many industries.
- Preparation for transportation.The gas produced contains numerous impurities. If their quantity is insignificant, gas is transported via tankers or pipelines to the plant for further processing. Natural gas is purified from a significant amount of impurities in complex preparation plants that are being built near the field.
Why do we need natural gas processing?
The formation of natural gas occurs in the periodthe formation of layers of porous rocks containing oil, and coal seams. In addition to components that are important for the needs of industry, it contains impurities that impede the process of transportation and use by end users.
Immediately after production, the gas in the integrated plantspreparation is drained, during which water and sulfur vapors are extracted from it. Further processing of natural and associated gas is carried out at chemical and gas processing plants.
The basic principle of the processing plants
The main task of the company engaged inprocessing of natural gas - the maximum possible extraction of all components of the fossil and bring them to a commercial state. At the same time, there should be no harm to the environment and the bowels of the earth, and financial costs should be kept to a minimum.
Due to the implementation of all aspects of this rule, natural gas products are considered high-quality and economical.
Processing methods
There are the following methods of gas processing:
- physical energy;
- chemical catalytic;
- thermochemical.
Physical energy methods are used forgas compression and its separation into components using cooling or heating installations. This natural gas processing technology is most often used directly in the fields.
Initially, the process of compression and separation was carried out using compressors. To date, less costly equipment has been used successfully - ejectors and oil pumps.
Chemical-catalytic method of processingNatural gas implies the conversion of methane to synthesis gas for its further processing. This can be done in three ways: steam or carbon dioxide conversion, partial oxidation.
Often used the method of partialmethane oxidation. This is due to the convenience of carrying out the process in the autothermal mode (when the raw material is heated by incomplete oxidation of hydrocarbons due to heat release), the reaction rate and the absence of the need to use a catalyst (as in steam and carbon dioxide conversion).
The resulting synthesis gas is not further subjected to the process of separation into components.
Термохимические способы подразумевают термическое impact on natural gas, resulting in the formation of unsaturated hydrocarbons (for example, ethylene, propylene). The implementation process is possible only at very high temperatures (about 11 thousand degrees Celsius) and a pressure of several atmospheres.
Processed products
For many people, the word "gas" is associated with fuel and a gas stove. In fact, the use of its components is more extensive:
- helium is a valuable raw material used in hightechnologies, such as in the manufacture of medical equipment and magnetic pillows for long trips in public transport, in the design of nuclear reactors and space satellites;
- formaldehyde, one of the derivatives of methane, -raw materials, which play an important role in the production of phenolic plastics (brake linings, billiard balls) and resins, which are an important component of building construction materials (plywood, fiberboard), paintwork and thermal insulation products;
- ammonia - used in pharmaceutical (aqueous solution), agricultural (fertilizer) and food (flavor enhancer) industries;
- ethane is the raw material from which polyethylene is produced;
- Acetic acid - widely used in the textile industry;
- methanol - fuel for vehicles.
Extraction and processing of natural gas - processes,thanks to which the most important industries are effectively developing. Gas comes to the end consumer after careful processing, its application considerably improves conditions of life.
