The Basics of Process Technology (Основы технологических процессов). Учебное пособие
.pdf9. Прочитайте и переведите
Glycol Dehydration
The use of Glycol to dehydrate gas streams is an established method that has proven its functionality and versatility time and again.
There are 3 common types of Glycol used for Gas Dehydration:
Mono-Ethylene Glycol (MEG)
Di-Ethylene Glycol (DEG)
Tri-Ethylene Glycol (TEG)
The design of TEG and MEG Dehydration Systems is unique for every requirement, and the overall package design will vary to meet the specified moisture content of the gas at the process conditions.
Each system is typically designed and built as a complete package with particular emphasis given to the following issues:
Discharge gas moisture content
High gas dehydration capacity
Minimum glycol losses
Minimum power consumption
Optimum plant efficiency & design integrity
Compliance with HSE requirements
10.Вставьте пропущенные слова, основываясь на схеме технологического процесса, приведенной ниже.
Process Description
In a typical TEG package, water saturated gas enters near the bottom of the Tower and flows upwards through the internal trays/packing (__). Lean Glycol enters the Tower near the top and cascades down through the Tower internals (__), making contact with the up-flowing gas stream. The counter-current flow path of the
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Glycol and the high contact surface area adsorbs water into the Glycol from the gas stream.
Dehydrated gas flows out of the top of the Tower, while the Rich Glycol flows out of the bottom of the Tower and to the Glycol Regeneration Package. The TEG Regeneration process typically involves passing the Rich Glycol through the still column to gain some heat (___) before entering the Flash Drum (___). The Glycol is then passed through Particle Filters to remove particulates and Activated Carbon Filters to remove any dissolved hydrocarbon and/or chemical compounds (___). The Rich Glycol is heated in a exchanger to preheat the feed (___) to the Still Column where the Glycol present in the water vapour leaving the Reboiler is recovered (___).
Depending on the application, it may be necessary to increase the Lean Glycol concentration by using stripping gas (7), or running the Reboiler/Still Column under a slight vacuum. Lean TEG (typically >99wt%) is then cooled and pumped back to the top of the Tower (___) to repeat the process.
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11. Выберите любую схему технологического процесса из курса «Процессы и аппараты химической технологии». Опишите ее, пользуясь лексическим материалом урока 6.
При описании установки обратите особое внимание на следующие вопросы:
∙What is the main practical application of the unit?
∙What are the basic parameters of the unit?
∙What is the capacity of the unit?
∙What products does this unit produce?
∙What is necessary to do to increase efficiency of the unit?
∙Why did you choose this equipment for your presentation?
12.Составьте рассказ о процессе ректификации и ректификационных колоннах
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Unit 7
ADSORPTION
1.Прочитайте следующие интернациональные слова вслух и, основываясь на значениях соответствующих русских слов, определите их значение:
adsorption, accumulate, adsorbent, molecular, atomic, gel, zeolite, spherical, monolith, diameter, stability, micropore, inert, toxic, polar, stable, amorphous, reaction, synthetic, regular, crystal, organic, activation, function
2. Прочитайте и переведите следующие глаголы:
to accumulate, to diffuse, to result, to enable, to prepare, to follow, to treat, to age, to pickle, to release, to manufacture, to include, to consist, to activate, to dry, to expose, to oxidize
3.Подберите эквивалентный перевод словосочетаний из колонки А в колонке В
|
А |
|
B |
1) |
activated carbon |
a) |
размер пор |
2) |
silica gel |
b) |
время выдержки |
3) |
abrasion resistance |
c) |
серная кислота |
4) |
thermal stability |
d) |
активированный уголь |
5) |
sodium silicate |
e) |
кристаллическая решетка |
6) |
sulphuric acid |
f) |
гидротермальный синтез |
7) |
crystal lattice |
g) |
силикагель |
8) |
hydrothermal synthesis |
h) |
окислитель |
9) |
oxidizing agent |
i) |
термостойкость |
10) |
carbon dioxide |
j) |
силикат натрия |
11) |
exposure time |
k) |
двуокись углерода |
12) |
pore size |
l) |
износостойкость |
|
|
|
|
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4. Прочитайте и переведите текст
Adsorbents
Adsorption is a process that occurs when a gas or liquid solute accumulates on the surface of a solid adsorbent, forming a molecular or atomic film (the adsorbate). It is different from absorption, in which a substance diffuses into a liquid to form a solution.
Activated carbon, silica gel and zeolites are used as the adsorbents.
The adsorbents are used usually in the form of spherical pellets, rods, moldings or monoliths with hydrodynamic diameter between 0.5 and 10 mm. They must have high abrasion resistance, high thermal stability and small micropore diameter, which results in higher exposed surface area and hence high capacity of adsorption. The adsorbents must also have a distinct macropore structure which enables fast transport of the gaseous vapours.
Silica gel is a chemically inert, nontoxic, polar and dimensionally stable amorphous form of SiO2. It is prepared by the reaction between sodium silicate and sulphuric acid, which is followed by a series of after-treatment processes such as aging, pickling, etc.
Zeolites are natural or synthetic aluminum silicates which form a regular crystal lattice and release water at high temperature. Zeolites are polar in nature. They are manufactured by hydrothermal synthesis of sodium aluminosilicate. Non-polar zeolites are synthesized by dealumination of polar zeolites. Non-polar zeolites are mostly used in non-polar organics removal.
Activated carbon can be manufactured from carbonaceous material, including coal, peat, wood, or nutshells. The manufacturing process consists of two phases, carbonization and activation. The carbonization process includes drying and then heating to separate by-products, including tars and other hydrocarbons, from the raw material. The carbonized particles are “activated” by exposing them to an oxidizing agent, usually steam or carbon dioxide, at high temperature. The size of the pores developed during activation is a
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function of the time that they are treated in this stage. Longer exposure times result in larger pore sizes.
Adsorption is operative in most natural physical, biological, and chemical systems, and is widely used in industrial applications such as activated charcoal, synthetic resins and water purification.
5.Определите, являются ли следующие утверждения верными в соответствии с текстом упражнения 4
∙Activated carbon can be manufactured by hydrothermal synthesis of sodium aluminosilicate.
∙The size of the activated carbon pores develop during activation.
∙The longer the activation time is the smaller the pore sizes of adsorbent are.
∙Zeolites are nonpolar in nature.
∙Adsorption is a process that occurs when the substance diffuses into a liquid or solid to form a solution.
6. Ответьте на вопросы по тексту упражнения 4
∙What is the difference between the adsorption and absorption process?
∙What types of adsorbents are used in industry?
∙What two processes are necessary to produce the activated carbon?
∙What factor is the most important for the pore size development of the activated carbon?
∙What types of zeolites do you know?
∙What are the most determinate and important adsorbent parameters?
7. Вставьте следующие слова и фразы и переведите текст: phenomenon, to release, opposite, molecular desorption, sorption equilibrium, to predict
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Desorption
Desorption is a ________ whereby a substance is ________ from or through a surface. The process is the ________ of sorption (that is, adsorption or absorption). This occurs in a system being in the state of ________ between bulk phase and an adsorbing surface. When the concentration of substance in the bulk phase is lowered, some of the sorbed substance changes to the bulk state.
Usually, the order of the desorption can be ________ by the number of elementary steps involved:
∙atomic or simple ________ will typically be a firstorder process (i.e. a simple molecule on the surface of the substrate desorbs into a gaseous form).
∙recombinative molecular desorption will generally be a second-order process (i.e. two hydrogen atoms on the surface desorb and form a gaseous H2 molecule).
8.Переведите предложения
∙Механизм процесса адсорбции отличается от механизма абсорбции тем, что извлечение вещества осуществляется твердым, а не жидким поглотителем.
∙В качестве адсорбентов применяются пористые твердые вещества, такие как активированный уголь, силикагель и цеолиты.
∙Адсорбенты должны иметь высокую износостойкость, термостойкость и адсорбционную способность.
∙Процесс получения высокопористого активированного угля состоит из двух этапов: перегонки и активации.
∙Силикагель – химически инертное, нетоксичное и полярное вещество.
∙Цеолиты являются полярными алюмосиликатами, выделяющими воду при высоких значениях температуры.
9. Составьте рассказ о различных типах адсорбентов
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Тестовый контроль знаний по материалу уроков 1-7
TEST (VERSION 1)
1. Закончите предложения, используя следующие слова: adsorption, hydrodynamics, thermal radiation, thermodynamics, fractionation,
1.… is fluid dynamics applied to liquids, such as water, alcohol, oil, and blood.
2.… is electromagnetic radiation emitted from the surface of an object which is due to the object's temperature.
3.A … is separation of the mixture into its component parts, or fractions, based on the differences in their volatilities.
4.… is a branch of physics that studies the effects of changes in temperature, pressure, and volume on physical systems at the macroscopic scale by analyzing the collective motion of their particles using statistics.
5.… is a process that occurs when a gas or liquid solute accumulates on the surface of a solid adsorbent, forming a molecular or atomic film.
2.Подберите эквивалентный перевод словосочетаний из колонки А в колонке В
|
А |
|
B |
1) |
abrasion resistance |
a) |
время выдержки |
2) |
thermal stability |
b) |
серная кислота |
3) |
sulphuric acid |
c) |
гидротермальный синтез |
4) |
hydrothermal |
d) |
термостойкость |
|
synthesis |
e) |
износостойкость |
5) |
exposure time |
f) |
теплообменник с |
6) |
parallel-flow heat |
|
параллельным током |
|
exchangers |
g) |
последняя фракция отгонки |
7) |
bottoms fraction |
h) |
определяющий линейный |
8) |
characteristic length |
|
размер |
9) |
thermodynamic |
i) |
термодинамическое |
|
equilibrium |
|
равновесие |
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3.Определите, к какой из следующих тематик относятся следующие словосочетания:
external reflux, heat exchanger, silica gel, free convection, zeolite, thermal radiation, pore size, tube bundle, distillation, mass transfer, adsorbate
Heat Transfer |
Fractionation |
Adsorption |
|
|
|
1. |
1. |
1. |
2. |
2. |
2. |
3. |
3. |
3. |
4. |
4. |
4. |
|
|
|
4. Определите и исправьте неточности в следующих предложениях.
∙For flow over a flat plate, the characteristic length is the diameter of the plate and the characteristic velocity is the free stream velocity.
∙Positive displacement pumps are based on bladed impellers which rotate within the fluid to impart a tangential acceleration to the fluid and a consequent increase in the energy of the fluid.
∙Cavitation is the term used to describe the formation of bubbles in liquid flow when the temperature increases.
∙According to the first law of thermodynamics the entropy of all systems and of all states of a system is zero at absolute zero.
∙In physics, a black body is an object that does not absorb any electromagnetic radiation that falls onto it.
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∙The parallel-flow heat exchanger is most efficient, in that it can transfer the most heat.
∙Absorption is a process that occurs when a gas or liquid solute accumulates on the surface of a solid adsorbent, forming a molecular or atomic film.
5.Переведите следующие предложения.
∙В качестве адсорбентов применяются пористые твердые вещества, такие как активированный уголь, силикагель и цеолиты.
∙Теплообменные аппараты широко используются на нефтеперерабатывающих заводах, в химическом производстве для обработки природного газа, на электростанциях и для кондиционирования и отопления помещений.
∙Конвекция – это перенос тепла вследствие движения и перемешивания макроскопических объемов газа или жидкости.
∙Теплота, сообщаемая системе, расходуется на изменение внутренней энергии системы и на совершение системой работы против внешних сил.
∙Перекачка жидкости в струйных насосах осуществляется с помощью кинетической энергии другой жидкости, которую называют рабочей.
∙Ламинарный поток течения встречается при низких значениях числа Рейнольдса, где доминирующее значение играют силы внутреннего трения, и характеризуется спокойным постоянным движением жидкости.
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