V. Say if the following statements are true or false. Correct the false ones.
1. Oil is found in underground deep, black lakes. 2. The "pores" and the oil droplets can be easily seen with the naked eye. 3. Petroleum is called “black gold” because it is always black. 4. Crude oil comes in a large variety of consistencies. 5. Formed hundreds of millions of years ago, crude oil occurs quite naturally and is the result of plant and animal remains trapped in fine-grained sediments being transformed by heat and pressure to produce gas and oil.
VI. Render the text about petroleum in the oral form.
UNIT 2
Natural
gas 
Lead - in
I. Look at the table and try to tell about the properties of natural gas.
|
Properties | |
|
Density and phase |
0.717 kg/m3, gas |
|
Melting point |
−182.5°C (90.6 K) at 1 atm 25 °C (298 K) at 1.5 GPa |
|
Boiling point |
−161.6°C (111.55 K) |
|
Triple point |
90.7 K, 0.117 bar |
II. Study and learn the vocabulary list:
triple point тройная точка (фазовой диаграммы)
methane [΄mi:Өein] метан
bed 1. основание; фундамент; плита; 2..слой породы; пласт
swamp gas газ болотистый
marsh gas болотный газ, метан
fossil fuel ископаемое топливо
sewage [΄sju:idz] сточные воды; нечистоты
sludge 1. шлам; ил; осадок; грязевой отстой; буровая грязь; 2. промывочный раствор, смешанный с разбуренной породой
manure [mə΄njuə] 1) навоз 2) навозный 3) удобрение 4) унаваживать
manure gas биогаз
propane [΄prəupein] пропан
ethane [΄eӨein] этан
butane [΄bju:tein] бутан
sulphur [΄sΛlfə] сера
hydrogen [΄haidridzən] водород
landfill 1) закапывание мусора, отходов 2) мусорная свалка
contaminant [kən΄tæminənt] загрязняющее вещество
sour кислый; сернистый; содержащий сероводород
mercaptan меркаптан
impurity загрязняющая примесь
monoxide [mo΄noksaid] одноокись
asphyxiant [æs΄fiksiənt] удушающее отравляющее вещество
asphyxiant gas удушающий газ
combustion [kəm΄bΛs∫ən] 1) горение, возгорание, сжигание; 2) процесс окисления
liquefied natural gas сжиженный природный газ
compressed natural gas сжатый природный газ, компримированный природный газ
tank truck автоцистерна
greenhouse effect парниковый эффект
flare факел (для сжигания неиспользуемого попутного газа на нефтепромысле)
gas cavern каверна-газохранилище
ammonia [ə΄məunjə] аммиак
associated gas попутный газ
water vapour водяной пар
siloxanes силоксаны
butyl [΄bju:til] бутил
subsidence [səb΄saidəns] оседание почвы
thio (also - thi-, thia) в названиях веществ имеет значение содержащий серу
III. Read the text carefully and say what you have learnt about natural gas. A. Chemical composition of natural gas
Natural gas is a gaseous fossil fuel consisting chiefly of methane (CH4). Although methane is always the main component, it may also include other gases such as oxygen, hydrogen, nitrogen, ethane, ethylene, propane, and even some helium.
The gas is found entrapped in the earth's crust at different depths beneath impervious strata, such as limestone, and may or may not be in association with oil. If oil is present it is called wet gas, else dry gas. When methane-rich gases are produced by the anaerobic decay of non-fossil organic material, these are referred to as biogas. Sources of biogas include swamps, which produce swamp gas; marshes, which produce marsh gas; landfills, which produce landfill gas, as well as sewage sludge and manure, by way of anaerobic digesters.
Natural gas is tasteless and odorless. However, before gas is distributed to end-users, it is odorized by adding mercaptans to assist in leak detection. Natural gas is, in itself, harmless to the human body - unlike carbon monoxide, for instance, it is not a poison. However, natural gas is a simple asphyxiant and can kill if it displaces air to the point where the oxygen content will not support life.
Natural gas can also be hazardous to life and property through an explosion. Natural gas is lighter than air, and so tends to dissipate into the atmosphere. But when natural gas is confined, such as within a house, gas concentrations can reach explosive mixtures and, if ignited, result in blasts that could destroy buildings. Methane has a lower explosive limit of 5% in air, and an upper explosive limit of 15%.