Petroleum Refining (Технологии и продукты переработки нефти). Учебное пособие

Unit 4

CRUDE OIL PRETREATMENT

1.Прочитайте следующие интернациональные слова вслух и, основываясь на значениях соответствующих русских слов, определите их значение.

Organic, metal, corrosion, catalyst, dehydration, typical, chemicals, electrostatic, extraction, agent, electrical, concentrate, filtering, viscosity, limit, ammonia.

2. Прочитайте и переведите следующие глаголы.

To contain, to reduce, to plug, to prevent, to remove, to desalt, to extract, to add, to dissolve into, to attach, to held, to settle out, to concentrate, to filter, to limit, to adjust, to discharge from, to draw from, to send.

3.Подберите эквивалентный перевод словосочетаний из колонки А в колонке В.

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4. Прочитайте и переведите текст.

Crude oil often contains water, inorganic salts, suspended solids, and water-soluble trace metals. As a first step in the refining process, to reduce corrosion, plugging, and fouling of equipment and to prevent poisoning the catalysts in processing units, these contaminants 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 agent.

In chemical desalting, water and chemical surfactants (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 tank where they settle out.

Electrical desalting is the application of high-voltage electrostatic charges 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 continuous.

A third and less common process involves filtering heated crude using diatomaceous earth.

The feedstock crude oil is heated to between 150ºF and 350ºF to reduce viscosity and surface tension for easier mixing and separation of the water. The temperature is limited by the vapor pressure of the crude-oil feedstock. In both methods other chemicals may be added. Ammonia is often used to reduce corrosion. Caustic or acid may be added to adjust the pH of the water wash. Wastewater and contaminants are discharged from the bottom of the settling tank to the wastewater treatment facility. The desalted crude is continuously drawn from the top of the settling tanks and sent to the crude distillation (fractionating) tower.

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The shear produced by pumping the water-and-crude mixture through pipes, elbows, tees, valves, and other restrictions generally results in the formation of a water-in-oil emulsion, which is stabilized by natural surfactants, mostly asphaltenes. This emulsion is most of the time broken at the production facility in a process generally referred to as dehydration, which consists in adding a demulsifier and submitting the emulsion to physical treatment to promote and speed up settling and phase separation.

It is generally easy to state that an emulsion is broken, but it is often difficult to give a numerical estimate of the stability of an emulsion that is not completely resolved. The stability, which is actually rather the persistence because an emulsion is not thermodynamically stable, may be estimated by measuring the volume of separated phases with time. The plot of the separated volume fraction versus time often exhibits a sigmoid shape, characteristic of a three-step process. First, the long-distance approach of drops because of gravitational sedimentation results in a compacted emulsion in which the drops are separated by thin films of external phase. Then, the second step is the drainage of the thin film, which depends upon the protective effect of the surfactant adsorbed at approaching interfaces. The surfactant performance essentially depends upon the nature of the different components, as well as temperature and pressure. If the film drains, it finally becomes so thin that it breaks, resulting in the third step, which is the coalescence of drops that produces the phase separation.

10.Переведите на слух по предложению следующий отрывок.

The salts that are most frequently present in crude oil are calcium, sodium and magnesium chlorides. If these compounds are not removed from the oil several problems arise in the refining process. The high temperatures that occur downstream in the process could cause water hydrolysis, which in turn allows the formation of hydrochloric acid. Salt deposits and fouls heat

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exchangers. Vaporization reduces crude pre-heat capacity. It can poison catalysts and cause ecological problems.

11.Подберите из текстов упражнений 9 и 10 английские эквиваленты к следующим словосочетаниям и выучите их наизусть.

откачка нефти водонефтяная эмульсия деэмульгатор сужение

ускорять процесс разделения фаз количественная оценка термодинамически стабильный

S-образный

трехступенчатый процесс

седиментация под действием силы тяжести

однородная фаза зависеть от защитное действие

12.Подберите русские эквиваленты к следующим словосочетаниям и выучите их наизусть.

result in

formation of

elbow

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it is easy to state completely resolved magnesium chloride to be removed from cause

hydrochloric acid pre-heat capacity

long-distance approach of drops coalescence of drops

promote

natural surfactants

13.Переведите письменно на русский язык следующие предложения.

1.Crude oil contains salts (calcium, sodium and magnesium chloride) which can cause different problems during the refining process.

2.Desalting is a process of oil refinery that removes salt from the crude oil.

3.There are two methods of crude oil desalting, chemical and electrostatic separation.

4.To dissolve impurities into the water the chemical surfactants are added to the oil.

5.Application of high-voltage electrostatic charges allows us to concentrate suspended water globules in the bottom of the settling tank.

6.Before separation of the water crude oil is heated to between 150ºF and 350ºF.

7.The temperature of heating is limited by the vapor pressure of oil.

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8.You should use the plot of the separated volume fraction versus time which has a sigmoid shape and characterizes three-step process.

9.The choice of surfactant depends upon the nature of the different components, as well as temperature and pressure.

10.The desalted crude is drawn from the top of the settling tank to the crude distillation tower.

14.Переведите письменно на английский язык следующие предложения.

1.Предварительная очистка сырой нефти заключается в обезвоживании и обессоливании.

2.В качестве экстрагентов используется вода и поверхностно активные вещества.

3.Соли и другие загрязняющие вещества растворяются в воде, а затем отводятся в отстойник.

4.Электрообессоливание основано на использовании электростатического заряда высокого напряжения.

5.Электростатический заряд концентрирует взвешенные глобулы воды в нижней части отстойника.

6.Для уменьшения коррозии часто используют аммиак.

7.Во время транспортировки водонефтяной смеси через трубные соединения, такие как колена, тройники и клапаны, образуется водонефтяная эмульсия.

8.Необходимо дать количественную оценку стабильности водонефтяной эмульсии.

9.Высокая температура может вызвать гидролиз, что, в свою очередь, приводит к образованию соляной кислоты.

10.Выбор поверхностно-активного вещества зависит от температурного режима процесса очистки нефти.

15.Переведите на слух в быстром темпе следующие словосочетания.

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Surfactant – загрязняющее вещество – high-voltage electrostatic charge – деэмульгатор – diatomaceous earth –

поверхностное натяжение – settling tank – обессоленная нефть

– emulsifier – нагреватель – water-in-oil emulsion –

электродегидратор – formation – количественная оценка – thermodynamically stable – S- образный – cause – колено – preheat capacity – зависеть от – speed up – седиментация под действием силы тяжести – desalt – коррозия – ammonia – отстойник.

16.Ответьте на вопросы по содержанию текстов данного урока.

1.What methods of crude oil pretreatment do you know?

2.What extraction agents are used in chemical and electrostatic separation?

3.What process can cause the formation of water-in-oil emulsion?

4.How can you estimate the stability of emulsion?

5.What problems will arise in the refining process if contaminants are not removed from the crude oil?

17.Передайте основное содержание текстов урока на русском и английском языках.

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Unit 5

OIL DISTILLATION

1.Прочитайте следующие интернациональные слова вслух и, основываясь на значениях соответствующих русских слов, определите их значение.

Distillation, engineering, processing, production, multicomponent, industry, separation, complex, cylindrical, typical, diameter, centimeter, meter, fraction, kerosene, diesel, asphalt, barrel, station, component.

2. Прочитайте и переведите следующие глаголы.

To distill, to separate into, to perform, to range, to mix, to condense, to stay, to settle, to require, to operate, to destine, to process, to rise, to vaporize.

3.Подберите эквивалентный перевод словосочетаний из колонки А в колонке В.

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