I. Read the text and match the paragraphs with the headings.

a. Formulating and Blending

b. Fractionation (distillation)

c. Other Refining Operations

d. Treatment

Conversion

II. Decide if the statements are true or false.

1. Crude oil is separated into groups of hydrocarbon compounds of differing boiling-point ranges called "fractions" or "cuts."

2. Decomposition doesn’t change the size and/or structure of hydrocarbon molecules.

3. Treatment include only the removal or separation of aromatics and naphthenes.

4. Finished products have specific performance properties.

5. Auxiliary operations and facilities may include sampling, testing, and inspecting.

III. Match the words and word combinations with their Russian equivalents.

1. distillation tower 2. impurity 3. sweetening 4. precipitation 5. light ends 6. stripping 7. tail gas 8. hydrocarbon compound 9. maintenance 10. dewaxing

1. углеводородное соединение 2. десорбирование 3. депарафинизация 4. очистка от активной серы 5. техническое обслуживание 6. загрязняющая примесь 7. легкие фракции нефти 8. образование осадка 9. перегонная колонна 10. отбензиненный газ

F igure 1. Refinery Process Chart

Description of petroleum refining processes

I. Read the text and complete the sentences with the words below. Text 4 Crude Oil Pretreatment (Desalting) and Distillation (Fractionation)

Crude oil often (1) …… water, inorganic salts, suspended solids, and water-soluble trace metals. As a first step in the refining (2) ……, to reduce corrosion, plugging, and fouling of equipment and to prevent poisoning the catalysts in processing units, these (3) …… must be removed by desalting (dehydration).

The two most typical methods of crude-oil desalting, chemical and electrostatic separation, use hot water as the extraction (4) ……. In chemical desalting, water and chemical surfactant (demulsifiers) are added to the crude, heated so that salts and other impurities dissolve into the water or attach to the water, and then held in a (5) ……. where they settle out. Electrical desalting is the application of high-voltage electrostatic (6) ……. to concentrate suspended water globules in the bottom of the settling tank. Surfactants are added only when the crude has a large amount of suspended solids. Both methods of desalting are (7) …….. A third and less-common process involves filtering heated crude using diatomaceous earth.

The first step in the refining process is the separation of crude oil into various fractions or straight-run cuts by distillation in atmospheric and vacuum (8) ……. The main fractions or "cuts" obtained have specific boiling-point ranges and can be (9) ……. in order of decreasing volatility into gases, light distillates, middle distillates, gas oils, and residuum. Within refineries there are numerous other, smaller distillation towers called (10) ……, designed to separate specific and unique products. Columns all work on the same principles. For example, a depropanizer is a small column designed to (11) …… propane and lighter gases from butane and heavier components. Another larger column is used to separate ethyl benzene and xylene. Small "bubble" towers called (12) …… use steam to remove trace amounts of light products from heavier product streams.

tank columns strippers separate towers charges process classified continuous agent contains contaminants