Технический текст "Natural Gas"

Natural gas

Natural gas is a natural mixture of gaseous hydrocarbons found issuing from the ground or obtained from specially driven wells. The composition of natural gas values in different localities. Its chief component, methane, usually makes up from 80 % to 95 %, and the balance is composed of varying amounts of ethane, pro­pane, butane, and other hydrocarbon compounds. Some of the hy­drocarbons found in gasoline also occur as vapors in natural gas; by liquefying these hydrocarbons, gasoline can be obtained.

Although commonly associated with petroleum deposits it also occurs separately in sand, sandstone, and limestone deposits. Some geologists theorize that natural gas is a byproduct of decaying vegetable matter in underground strata, while others think it may be primordial gases that rise up from the mantle. Because of its flammability and high calorific value, natural gas is used exten­sively as an illuminant and a fuel.

Natural gas was known to the ancients but was considered by them to be a supernatural phenomenon because, noticed only when ignited, it appeared as a mysterious fire bursting from the ground. One of the earliest attempts to harness it for economic use oc­curred in the early 19th cent, in Fredonia, N.Y. Toward the latter part of the 19th cent., large industrial cities began to make use of natural gas, and extensive pipeline systems have been constructed to transport gas.

Liquefied natural gas, or LNG, is natural gas that has been pressurized and cooled so as to liquefy it for convenience in ship ping and storage. The boiling point of natural gas is extremely low, and only in the 1970s did cryogenic technology advance enough to make the production and transport of LNG commercially feasi­ble. Some of the natural gas moved to and from the United States is carried as LNG in special tankers.

 

Active vocabulary

 

Try to memorize the following words and phrases.

 

Nouns and noun phrases

well                                   

limestone                        

mantle

vapor                                 

strata                              

flammability

convenience                       

by-product                        

tanker

illuminant

Verbs and verbal phrases

to theorize                      

to issue

Adjectives

liquefying                      

decaying                          

primordial

calorific                           

ignited                             

extensive

pressurized                     

feasible                            

cryogenic

Adverbs

separately

 

 

хорошо

известняк

мантия

пар

слои

воспламеняемость

удобство

побочный продукт

танкер

источник света

 

теоретизировать

выдавать

 

cжижение

разлагающийся

исконный

теплотворный

воспламеняемый

обширный

герметичный

осуществимый

криогенный

 

отдельно

Last modified: Sunday, 14 December 2014, 12:54 AM