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Файл:Английский язык для специалистов в области нефтегазового дела (Professional English for Oil and Gas Engineering). Учебное пособие
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Упражнение 8. Переведите текст, пользуясь словарем.
There are three main types of gasifier - fixed bed, fluidised
bed, and entrained flow - which together represent the most
promising methods to gasify biomass and waste.
Fixed bed gasifiers are suitable for small-scale processes, i.e., less
than 10 MW. Feedstock flows by gravity, while the gas flow can
be either updraft or downdraft. Ideally, the feedstock should be
piece-like and fairly homogeneous to flow smoothly in the reactor.
In practice, however, it contains fines and fibrous material, which
cause problems in the fuel flow leading to operational problems.
The flow problems can be avoided by applying a new type of
technology (‘Novel’ fixed bed gasifier) in which the flow is forced.
Fluidised bed reactors could solve the problems related to
nonhomogeneity of the feedstock, but they are too expensive in
small scale. In fluidised bed technology, the feedstock must be
crushed to millimetre size before it is gasified in either bubbling or
circulating mode. These gasifiers are suitable for scales up to
hundreds of megawatts. Recently, fluidised bed technology was
applied for wastes where the product gas is combusted in a
pulverised coal-fired boiler. The same method has been used to
recover aluminium from the reject produced in liquid packaging
board. The circulating fluidised bed has been demonstrated to be
particularly suited for fuels containing high contents of alkali
metals, where ash sintering problems can be avoided by using
limestone and special arrangements with the feeds.
In the third type of gasifier, the entrained flow gasifier,
pulverised fuel is gasified at high temperature. This is regarded as
one of the optional processes for liquid fuel manufacture from
biomass and wastes. High pressure gasification based on the
entrained flow process can be applied to improve the energy recovery
from black liquor.
Упражнение 9. Составьте аннотацию текста «The
BGL Slagging Gasifier».
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Упражнение 10. Подготовьте небольшие сообщения по
glycol dehydrator –
гликолевый водоотделитель
granular solids – зернистая
порода
impurities – примеси
silica gel – силикатный гель
silicon alumina beads –
гранулы кремния и оксида
алюминия
molecular sieve –
молекулярное сито,
ультрафильтр
transmission line –
транспортирующий
трубопровод
to retain – удерживать
solid desiccant dehydrator –
влагоотделитель с твёрдым
осушителем
следующим вопросам:
1. Характеристика различных типов газогенераторов.
2. Сущность технологических процессов с генераторным
газом.
3. Сущность процесса сухого золоудаления Лурджи.
4. Характеристика шлакоудаляющего газогенератора.
Упражнение 1. Прочтите слова и словосочетания и
постарайтесь запомнить их русские эквиваленты.
affinity – родство,
сходство, близость
alumina – окись алюминия;
глинозем
antifreeze agent –
противоморозная добавка
bead – шарик
to bubble through/up –
contactor/sober –
контактор, замыкатель;
контактный фильтр
desiccant –
влагопоглотитель
drying agent – сушильный
агент
glycol absorber –
гликолевый абсорбер,
поглотитель
UNIT 8
63
Упражнение 2. Переведите слова, обращая внимание
на суффиксы и префиксы.
Dehydrate – dehydrator - dehydration, absorb – absorber –
absorption, adsorb – adsorption, down – downward, up – upward,
exchange – exchanger, cool – cooling, compress – compression,
sufficient – sufficiently, advantage – disadvantage, transmit –
transmission, objection – objectionable.
Упражнение 3. Прочтите и переведите
интернациональные слова.
Method, temperature, hydrate, antifreeze, agent, methanol,
glycol, industry, category, principle, injection, process, material,
line, cubic, sulphide, carbon dioxide, physical, technique.
Прочтите и переведите текст, а затем выполните
следующие упражнения.
DEHYDRATION SYSTEMS
Several methods can help prevent hydrates from forming in a
gas line:
Heat the gas stream so that gas temperature will not drop to
the level at which hydrates form.
Add an antifreeze agent such as methanol or glycol to the
gas stream.
Remove the water vapour by using a glycol dehydrator,
which consists of a vertical pressure vessel (a glycol absorber) that
allows the glycol to flow downward as the gas flows upward.
Dehydrate using drying agent such as alumina, silica gel,
silicon alumina beads, or a molecular sieve.
Expand the gas and refrigerate using heat exchangers.
Dehydration systems used in the natural gas industry fall into
four categories in principle: (a) direct cooling, (b) compression
followed by cooling, (c) absorption, and (d) adsorption.
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Dehydration in the first two methods does not result in sufficiently
low water contents to permit injection into a pipeline. Further
dehydration by absorption or adsorption is often required.
Absorption is a process in which water vapour is removed
from natural gas by bubbling the gas counter-currently through
certain liquids that have a special attraction or affinity for water.
Water vapour in the gas bubbles is entrained in the liquid and
carried away by the liquid. Adsorption is a process in which gas
flows through a bed of granular solids that have an affinity for
water. The water is retained on the surface of the particles of the
solid material. The vessel that allows either the absorption or
adsorption process to take place is called the contactor or sober.
The liquid or solid that has affinity for water and is used in the
contactor in connection with either of the processes is called the
desiccant. Two major types of dehydration equipment in use today
are the liquid desiccant dehydrator and the solid desiccant
dehydrator. Each type of dehydrator has its advantages and
disadvantages. These two types of dehydrators dehydrate
practically all the natural gas moved through transmission lines.
Most dehydrated gas contains no more than 7 pounds of
water vapour per million cubic feet of gas (lbs/ MMcf).
Other objectionable impurities that are found are hydrogen
sulphide and carbon dioxide. These impurities may be removed
using chemical reactions, physical solutions, or absorption. The
technique used depends on how free of impurities the gas must be
before a gas company will purchase it.
Упражнение 4. Найдите в тексте данные ниже слова и
словосочетания и напишите их русские эквиваленты.
Natural gas industry, expand, gas temperature, carbon
dioxide, result in, physical solutions, impurities, water vapour,
sufficiently low water contents, gas line, liquid, dehydration
systems, chemical reactions, a bed of granular solids, hydrogen
sulphide, the surface of the particles, heat exchangers, gas stream,
solid material, dehydration equipment, the liquid desiccant
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dehydrator and the solid desiccant dehydrator, vertical pressure
1. The vessel that allows either
the absorption or adsorption
process to take place is called
…
1. how free of impurities the
gas must be before a gas
company will purchase it.
2. Other objectionable
impurities that are found are …
2. four categories in
principle: (a) direct cooling,
(b) compression followed
by cooling, (c) absorption,
and (d) adsorption.
3. Adsorption is a process in
which …
3. the liquid desiccant
dehydrator and the solid
desiccant dehydrator.
vessel, transmission lines, refrigerate, objectionable impurities.
Упражнение 5. Найдите в тексте ответы на следующие
вопросы.
1. What should be done to prevent hydrates from forming in a
gas line?
2. What types of dehydration systems are used in the natural
gas industry?
3. What is absorption?
4. What is adsorption?
5. What is called the contactor?
6. What is called the desiccant?
7. What types of dehydration equipment are in use today?
8. What objectionable impurities can be found in dehydrated
gas?
9. How may the impurities be removed?
10. What does the technique used depend on?
Упражнение 6. Подберите из правой колонки
соответствующие окончания предложений из левой колонки.
66
4. The technique used depends
on …
4. water vapour is removed
from natural gas by
bubbling the gas countercurrently through certain
liquids that have a special
attraction or affinity for
water.
5. Dehydration systems used
in the natural gas industry fall
into …
5. is entrained in the liquid
and carried away by the
liquid.
6. Direct cooling and
compression followed by
cooling do no result in …
6. gas flows through a bed
of granular solids that have
an affinity for water.
7. Most dehydrated gas
contains …
7. hydrogen sulphide and
carbon dioxide.
8. Absorption is a process in
which …
8. the contactor or sober.
9. Water vapour in the gas
bubbles …
9. sufficiently low water
contents to permit injection
into a pipeline.
10. Two major types of
dehydration equipment in use
today are …
10. no more than 7 pounds
of water vapour per million
cubic feet of gas.
Упражнение 7. Переведите текст, пользуясь словарем.
DEHYDRATION OF NATURAL GAS
The term dehydration means removal of water vapor. All
natural gas downstream from the separators still contains water
vapor to some degree. Water vapor is probably the most common
undesirable impurity found in untreated natural gas. The main
reason for removing water vapor from natural gas is that water
vapor becomes liquid water under low-temperature and/or high
67
pressure conditions. Specifically, water content can affect longdistance transmission of natural gas due to the following facts:
Liquid water and natural gas can form hydrates that may
plug the pipeline and other equipment.
Natural gas containing CO2 and or H2S is corrosive when
liquid water is present.
Liquid water in a natural gas pipeline potentially causes
slugging flow conditions resulting in lower flow efficiency of the
pipeline.
Water content decreases the heating value of natural gas
being transported.
Solubility of water in natural gas increases with temperature
and decreases with pressure. Salt’s presence in the liquid water
reduces the water content of the gas. Water content of untreated
natural gases is normally in the magnitude of a few hundred
pounds of water per million standard cubic feet of gas
(lbm/MMscf); while gas pipelines normally require water content to
be in the range of 6-8 lbm/MMscf and even lower for pipelines in
deep water.
The water content of natural gas is indirectly indicated by the
dew point, defined as the temperature at which the normal gas is
saturated with water vapor at a given pressure. At the dew point,
natural gas is in equilibrium with liquid water; any decrease in
temperature or increase in pressure will cause the water vapor to
begin condensing. The difference between the dew point
temperature of water-saturated gas stream and the same stream
after it has been dehydrated is called dew-point depression.
It is essential to accurately estimate the saturated water vapor
content of natural gas in the design and operation of dehydration
equipment. Dalton’s law of partial pressures is valid for estimating
water vapor content of gas at near-atmospheric pressures.
Упражнение 8. Переведите предложения на английский
язык.
1. Термин “осушка” означает удаление водяного пара.
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2. Используя влагопоглотители, дегидратационные
установки могут удалять практически всю воду из природного
газа.
3. В газовой промышленности используется четыре типа
дегидратационных систем: непосредственное охлаждение;
сжатие с последующим охлаждением; абсорбция и адсорбция.
4. Растворимость воды
в природном газе повышается с
увеличением температуры и понижается с увеличением
давления.
5. Вода удерживается на поверхности частиц твердого
материала.
6. Сегодня используется два основных типа дегидратационного оборудования: дегидратор с жидким поглотителем
и дегидратор с твердым поглотителем.
7. Наличие в жидкой воде соли снижает водосодержание газа.
8. На водосодержание газа косвенно указывает
температура конденсации.
9. Такие примеси, как сероводород и углекислый газ,
можно удалить, используя химические реакции, физические
растворы или абсорбцию.
10. Водяной пар является самой распространенной
нежелательной примесью в неочищенном газе.
Упражнение 9. Составьте сообщение по тексту
«Dehydration Systems», используя в качестве плана ответы
на вопросы упражнения 5.
Упражнение 10. Представьте, что:
1. Вы – лектор, читающий лекцию о способах обработки
газа. Расскажите о существующих типах дегидратационных
систем и процессах, применяемых для осушки газа.
2. Вы проводите экскурсию для студентов на предприятии, производящем осушку газа. Расскажите, почему
необходимо производить осушку газа.
69
Упражнение 1. Прочтите слова и словосочетания и
adsorption dehydration –
адсорбционная осушка
to bypass – обходить
a contaminant – примесь
a desiccant bed –
влагопоглотительный слой
to desorb – десорбировать,
извлекать
a direct-fired heater –
нагреватель с прямым
обогревом
disturbance – смещение
a filter separator – фильтрвлагоотделитель
a gas cooler – установка
охлаждения газа,
газоохладитель
an indirect heater –
нагреватель с косвенным
обогревом
inlet gas – поступающий газ
lubricating oil –смазочное
масло
power-operated valves –
приводная трубопроводная
арматура
a regeneration gas heater –
нагреватель с
регенерационным газом
regeneration heat – теплота
регенерации
to shut off – выключать
a step – этап
a substance – вещество
a timing device – реле
времени, таймер
постарайтесь запомнить их русские эквиваленты.
Упражнение 2. Переведите слова, обращая внимание на
суффиксы.
To adsorb – adsorption – adsorbent – adsorber, to dehydrate
– dehydration – dehydrator, to separate – separator, to disturb –
disturbance, to heat – heater, to arrange – arrangement, direct –
indirect, to generate – to regenerate, up – upward, down –
downward, to use – usable, to contaminate – contaminant, normal
– normally – abnormally.
UNIT 9
70
Упражнение 3. Прочтите и переведите интернаци-
ональные слова.
A substance, to concentrate, silicate, molecular, natural,
efficiency, gas, a filter separator, regeneration, to contact, to condense,
to activate, normal, effective, degradation, blockage, capillary,
corrosion, inhibitor, cycle, sulfide.
Прочтите и переведите текст, а затем выполните
следующие упражнения.
DEHYDRATION BY ADSORPTION
Adsorption is defined as the ability of a substance to hold gases
or liquids on its surface. In adsorption dehydration, the water vapour
from the gas is concentrated and held at the surface of the solid
desiccant. Solid desiccants have very large surface areas per unit
weight to take advantage of the surface forces. The most common solid
adsorbents used today are silica, alumina, and certain silicates known
as molecular sieves. Dehydration plants can remove practically all
water from natural gas using solid desiccants. Because of their great
drying ability, solid desiccants are employed where higher efficiencies
are required.
The incoming wet gas should be cleaned by a filter separator to
remove solid and liquid contaminants in the gas. The filtered gas flows
downward during dehydration through one adsorber containing a
desiccant bed. The down-flow arrangement reduces disturbance of the
bed caused by the high gas velocity during the adsorption. While one
adsorber is dehydrating, the other adsorber is being regenerated by a
hot stream of inlet gas from the regeneration gas heater. A direct-fired
heater, hot oil, steam, or an indirect heater can supply the necessary
regeneration heat. The regeneration gas usually flows upward through
the bed to ensure thorough regeneration of the bottom of the bed,
which is the last area contacted by the gas being dehydrated. The hot
regenerated bed is cooled by shutting off or bypassing the heater. The
cooling gas then flows downward through the bed so that any water
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