A. Comprehension

Answer the questions:

1. What is natural gas? Give its short definition .

2. What is the typical composition of natural gas?

3. How can natural gas liquids be separated from natural gas?

4. Explain the difference between the terms ‘dry’ and ‘wet’ gas?

5. Name the main physical properties of natural gas.

6. Why is natural gas odorized by adding thiols?

7. Is natural gas a poison? Can it kill?

8. How can natural gas be measured? Name the main ways.

9. How can natural gas be used?

10. What do production companies do after they extract natural gas from underground?

B. Vocabulary Practice

I. Give English equivalents for:

1) встречающаяся в природе смесь углеводородных и неуглеводородных газов; 2) легковоспламеняющаяся смесь; 3) выделять большое количество тепла при горении; 4) сжижаться на поверхности; 5) пластовая вода; 6) частично конденсироваться при транспортировке; 7) газ, добытый из скважины; 8) иметь отчетливый проникающий запах; 9) помогать в обнаружении утечки; 10) быть легче воздуха; 11) иметь тенденцию рассеиваться в атмосферу; 12) быть ограниченным в своём распространении; 13) являться удушающим отравляющим веществом; 14) объем, занимаемый природным газом при нормальной температуре и давлении; 15) измерять природный газ в кубических футах; 16) британская тепловая единица; 17) постоянно нуждаться в энергии; 18) бытовое, коммерческое и промышленное использование природного газа; 19) быть тесно связанным с месторождением нефти; 20) использовать сложные технологии для того, чтобы обнаружить местонахождение природного газа; 21) бурить скважины там, где есть вероятность обнаружить природный газ; 22) очищать природный газ для того, чтобы освободить его от таких примесей как вода, песок и другие газы; 23) транспортировать по газопроводу; 24) типичный состав природного газа до переработки; 25) практически чистый метан.

II. Give Russian equivalents for:

to be clean burning; 2) to emit lower levels of potentially harmful byproducts into the air; 3) combustible mixture of hydrocarbon gases; 4) to be formed primarily of methane; 5) to include ethane, propane, butane and pentane; 6) to be gaseous under atmospheric conditions; 7) to liquefy at the surface at atmospheric pressure; 8) natural gas liquids/ gas condensate/ natural gasoline/ liquefied petroleum gas; 9) to separate in some reservoirs through retrograde condensation; 10) to occur in association with the hydrocarbon gases; 11) formation water 12) to occur together in the reservoir 13) to contain water vapour 14) typical make up of natural gas before it is refined;15) to be considered 'dry' or 'wet' 16) colour, odour, and flammability 17) to impart a decided odour; 18) to be odorized by adding thiols; 19) harmless to the human body; 20) to be a simple asphyxiant; 21) lower explosive limit \upper explosive limit; 22) to be calculated in cubic metres; 23) to be measured as a source of energy; 24) to remove impurities; 25) to be transmitted through a network of pipeline

III. Fill in the appropriate word(s) from the list below into the extracts and translate them into Russian:

а) methane, to form, breakdown, proximity, heavier hydrocarbons, paraffin, hydrocarbon gases, mantle, bacterial, oxidation, decay.

Hydrocarbon gases

… are largely composed of the … series - straight and branched, single bonded changes of hydrocarbons.

(1) … is the largest constituent of natural gas. It can … in three ways:

(a) Mantle methane. Derived from the … (presumably primordial methane).

(b) Microbial methane. As a reaction product of the bacterial … of organic matter. Large caused by the reduction of CO2 during … of the organic matter.

(c) Thermogenic methane. Thermal … of heavier hydrocarbons.

(2) Heavier hydrocarbons:

Rarely (perhaps never) formed by … processes. Thus the presence of … in natural gas probably reflects … to liquid hydrocarbon reservoir.

b) formation, continuation, chemical, temperature, atmospheric, asphyxiation, be actively produced, warning, deadliest, oceanic, to dull, ppt, radioactive, compounds, thermal, maturation, to originate, depth, paralysis, decomposition, inert, numerous, mobile, reactive, crust, to form

Non-hydrocarbon gases

Noble Gases - Helium, Argon, and Radon

These gases are … - do not take part in … reactions. They … from decay of … isotopes of various elements, predominately the U series elements.

Nitrogen

Three potential origins of nitrogen: (1) through oxidation of NH4, which is derived from … breakdown of organic matter. (2) … origin (atmosphere is 70% nitrogen). (3) Mantle out gassing - … of the out gassing that started soon after the … of the earth.

Hydrogen

Hydrogen is so … and …, it cannot be permanently retained in the subsurface. It must … with in reservoir, adjacent source beds, or diffusing upward from .… Possible origins include: (1) from reactions in the … that involve Ferrous iron reduction, and (2) during thermal … of organic matter.

Carbon dioxide

CO2 has erratic distribution in the subsurface because of … sources and variations in solubility.

Sources: two organic and one inorganic

a) Thermal degradation of organic matter. Largely from the … of oxygen bearing groups in organic matter. Usually derived from continentally derived organic matter.

b) Inorganic clay reactions - largely from reaction between carbonates and kaolinite … chlorite.

c) Volcanic activity. Decomposition of carbonate rocks during injection of high … magmas and by acidic water.

Hydrogen sulfide

The … gas produced in large quantities. 1 … causes respiratory … and sudden but agonizing death from … . Can't rely on foul odor as … - at concentrations below 0.1 ppt, H2S … sense of smell, increasing concentrations won't be noticed.

Origin:

a) Inorganic cracking of sulfur bearing organic … - generally found at temperatures > 120°C

b) Reduction of sulfate - perhaps the greatest source of sulfate, particularly in … sediments.

c) underground, to decay, fossil fuel, petroleum, methane , to be confused, remains, nonrenewable, hydrocarbon, escaping, electricity, odorant, nonhydrocarbons, safety, materials, by-products, gas, to undergo, raw

Natural gas is generally considered a … fossil fuel. Natural gas is called a ... because most scientists believe that natural gas was formed from the ... of tiny sea animals and plants that died 200-400 million years ago. … natural gas is a mixture of … compounds and small quantities of various … existing in the gaseous phase or in solution with crude oil in natural … reservoirs at reservoir conditions.

Its main ingredient is …, a natural compound that is formed whenever plant and animal matter … . By itself, methane is odorless, colorless, and tasteless. As a … measure, natural gas companies add a chemical … (it smells like rotten eggs) so … gas can be detected. Natural gas is often informally referred to as simply …, especially when compared to other energy sources such as … . Before natural gas can be used as a fuel, it must … extensive processing to remove almost all … other than methane. The … of that processing include ethane, propane, butanes, pentanes and higher molecular weight hydrocarbons, elemental sulfur, and sometimes helium and nitrogen. Natural gas should not … with gasoline, which is made from … .

d) Natural, air, flammable, level, to reach, combustion, presence, smell, to be expressed, flame.

Natural gas will not explode in the … of a flame until it … a very specific concentration in the air - below a certain … it is deemed too lean to burn and above a certain level it may be too rich to burn. Within a … range, the gas will ignite and may cause an explosion.

The flammable range … by Lower Explosive Limit ("LEL") and Upper Explosive Limit ("UEL"). The LEL is the concentration of natural gas in the … below which the propagation of a … will not occur on contact with an ignition source. The natural gas LEL is 5%. This means that, in most cases, the … of gas would be detected well before … conditions are met. The UEL is the concentration of natural gas in the air above which the propagation of a flame will not occur on contact with an ignition source. The … gas UEL is 15%.

IV. Match the following terms with their definitions and give their Russian equivalents:

retrograde condensation, natural gas, fossil fuel, cubic feet, methane, British thermal unit, liquefied natural gas, natural gas liquids.

1. The lightest and most abundant of the hydrocarbon gases and the principal component of natural gas. It is a colorless, odorless gas that is stable under a wide range of pressure and temperature conditions in the absence of other compounds.

2. The formation of liquid hydrocarbons in a gas reservoir as the pressure in the reservoir decreases below dew point pressure during production. It is called this way because some of the gas condenses into a liquid under isothermal conditions instead of expanding or vaporizing when pressure is decreased.

3. A naturally occurring mixture of hydrocarbon gases that is highly compressible and expansible. Methane (CH4) is the chief constituent of it.

4. Any naturally occurring carbon or hydrocarbon fuel, such as coal, petroleum, peat, and natural gas, formed by the decomposition of prehistoric organisms.

5. Natural gas, mainly methane and ethane, which has been liquefied at cryogenic temperatures. This process occurs at an extremely low temperature and a pressure near the atmospheric pressure.

6. Components of natural gas that are liquid at surface in field facilities or in gas-processing plants.

7. A measure of heat energy required to raise the temperature of one pound of water by one degree Fahrenheit.

8. A common measure for gas volume. Standard conditions are normally set at 60oF and 14.7 pounds per square inch.

V. Explain the following terms using a specialized dictionary and glossary, give their Russian equivalents and make up your own sentences with them:

condensation, ‘dry’ gas, ‘wet’ gas, non-hydrocarbon gases

VI. Give English translation for:

Свойства и польза природного газа

Природный газ – нетоксичен.

Природный газ не содержит ядовитых компонентов, которые могут всасываться в кровь при дыхании.

Природный газ легче, чем воздух.

Если природный газ выбрасывается в атмосферу, он быстро рассеивается. Более же тяжелые чем воздух пары бензина и пропан, оседают и накапливаются около поверхности земли.

Природный газ бесцветен.

Смешанный с определенным количеством воздуха и зажженный, природный газ горит чистым, синим пламенем. Это топливо полного сгорания, генерирующее тепло, углекислый газ и водяной пар.

Природный газ не имеет запаха.

Добытый из недр земли природный газ не имеет запаха. Резкий, но безвредный запах придаётся газу в целях безопасности. Пахучее вещество настолько сильно, что вы сможете почувствовать запах даже небольшого количества газа в случае утечки.

У природного газа ограниченный предел воспламеняемости.

Это помогает гарантировать прогнозируемое, безопасное использование. Природный газ загорится лишь в том случае, когда в воздушно-газовой смеси доля природного газа будет составлять от 5 до 15 процентов. Любая смесь, содержащая меньше чем 5 или больше чем 15 процентов природного газа, не загорится.

Природный газ способствует сохранению более чистой окружающей среды.

Природный газ является самым чисто сгораемым ископаемым топливом. Это помогает улучшить состояние воздуха и качество воды, особенно когда природный газ используется там, где используются источники энергии, загрязняющие окружающую среду. При горении природный газ фактически не производит никаких вредных загрязняющих веществ.