Natural gas

Natural gas either occurs together with crude oil or forms separate deposits of gas alone. Decomposition of both animal and vegetable remains over a period of many centuries without air is the source of natural gas. A great volume of gas accumulates and penetrates into porous beds of sand, sandstones and limestones. In these beds gas can form natural deposits under great pressure. When a borehole reaches such a deposit the gas rushes up. This gas has to be collected from several boreholes with the help of pipelines over long distances. Russia has a gigantic network of pipelines.

Natural gas is an inflammable gas and consists of hydrocarbons with a very low boiling point. Methane (CH4) makes up approximately 85 per cent of the typical natural gas. Ethane (C2 H6) can be present up to 10 % and propane (C3 H8) up to 3 %.

Butane, pentane, hexane, octane and a few other gases may also be present. In contrast to crude petroleum natural gas has no distinct odour.

Little of natural gas we may use chemically,most of it we use as a fuel for the production of both heat and energy. Like all gaseous fuels natural gas gives a great amount of heat. Natural gas is valuable also as an important chemical raw material for industry, as chemical technologists are able to obtain hydrogen, acetylene, carbon black and various chlorine derivatives.

Natural gas occurs mainly in Russia and some other CIS countries and in the United States where most of the extraction and utilization takes place. Before the war we utilized gas only at Baku and in the Carpathian Mountains. Since then they have discovered numerous new sources, for example, in the Ukhta (Russia) and Emba regions (Kazakhstan), near Saratov, Fergana (Uzbekistan), Samara,Volgograd and Grozny. In Europe they found rich deposits in Rumania and Italy, smaller ones in Austria and France. Germany also has several small but intensively worked fields.

18. Ответьте на следующие вопросы:

1. Does natural gas occur together with crude oil or does it form separate deposits? 2. What is the main source of natural gas? 3. In what beds can gas form natural deposits? 4. What happens when a borehole reaches a deposit of natural gas under great pressure? 5. What network of pipelines has Russia? 6. Is natural gas an inflammable gas? 7. What does natural gas consist of? 8. What is the main component of natural gas? 9. Has natural gas any distinct odour? 10. Do we use natural gas mainly as a fuel? 11. Is natural gas an important chemical raw material for industry? 12. What countries are the main producers of natural gas? 13. In what areas of Russia and CIS is natural gas produced at present? 14. What countries of Europe are rich in natural gas?