gas plant processing
TRANSCRIPT
-
8/19/2019 Gas Plant Processing
1/36
Refd.web site link; http://www.industrialgasplants.com/cryogenic-oxygen-
plant.html#oxygen
Air Separation Plant
Air separation plants are gas plants producing different varieties of gases by the process of air separation.
Air separation plants produce the atmospheric industrial gases like oxygen, nitrogen, argon, helium,
methane using air and electrical power as raw materials.
Air Separation Technology
Though there are differences in process details displaying desired product mix and other factors, all air
separation plants make use one of the following two types of process technology:
• Cryogenic plants: The air separation technique used in cryogenic plants produce gas and liquid
products (liquid oxygen, liquid nitrogen etc. using very low temperature distillation which separates
air components and produce desired product purities.
• Non-cryogenic plants: The air separation technique used in non cryogenic plants produce
gaseous products with near!ambient temperature separation processes. They use differences in
properties like molecular structure, si"e and mass to produce oxygen or nitrogen.
All manufacturers and suppliers involved with air separation plants deal with the design, fabrication, and
construction of both cryogenic and non!cryogenic air separation plants. The main focus of the market in
today#s scenario is to supply independent operators of air separation systems with design, engineering, and
operations support. $n some cases this involve actual pro%ect work, and in some other it means providing
design, engineering and supervision.
http://www.industrialgasplants.com/cryogenic-oxygen-plant.html#oxygenhttp://www.industrialgasplants.com/cryogenic-oxygen-plant.html#oxygenhttp://www.industrialgasplants.com/cryogenic-oxygen-plant.html#oxygenhttp://www.industrialgasplants.com/cryogenic-oxygen-plant.html#oxygen
-
8/19/2019 Gas Plant Processing
2/36
Capabilities of Air Separation Plants
&lant types offered by air separation plants include:
• 'xygen non cryogenic plant
• 'xygen cryogenic plant
• itrogen &)A plant
• itrogen cryogenic plant
• *odular liquid and gaseous cryogenic+non cryogenic nitrogen generators
• *odular liquid and gaseous cryogenic+non cryogenic oxygen generators
• arge gaseous cryogenic nitrogen generators+ oxygen generators
• iquid plants producing liquid oxygen, nitrogen and argon
Air Separation Plant Design
The basic elements considered in the design of an air separation plant are:
• Air &retreatment
• Air -ompression
• efrigeration
• /istillation
0esides that argon purification and+or product compression are also required. Air pretreatment systems
make use of either temperature swing or pressure swing adsorption technologies and usually efficient in
dealing with any environmental condition.
Buyer's Guide:Specifications of Air Separation Plants
Standard ype !ain "roducts Sec. "roducts pplications'xygen + itrogen 1as1enerating &lant
'xygen gas + 22.34itrogen gas + 22.22224
$i%uid nitrogen&
li%uid oxygen& argon&neon& krypton& xenon
$ron works, chemical,partial oxidation
ow &ressure iquid'xygen +iquid itrogen1enerating &lant
iquid 'xygen + 22.54iquid nitrogen + 22.22224
Argon $ndustrial gas sales
6igh &urity &ressuri"editrogen 1enerating &lant
itrogen gas + 22.22224 iquid nitrogen -hemical, petroleum,textiles, electronics industry
ses of Air Separation Plants
• Steel 'ndustries
• (on-steel !etal 'ndustries
• )lectronics
• "ower *enerating 'ndustries
• +hemical ,"etrochemical
• Semiconductor 'ndustries
• il , *as
• ood , e0erage
• !etals
• 1elding 'ndustries
• !ining
• *lass
• "ulp , "aper
• 'ndustrial gas
• )n0ironmental
• !edical
• Refrigeration
Cryogenic Liquid Plant
-
8/19/2019 Gas Plant Processing
3/36
-ryogenic iquid *anufacturing process 0enefits
7quipment equired 0uyers 1uide
-ryogenic liquid plants are gas plants producing liquid oxygen or liquid nitrogen in the cryogenic process.
-ryogenic process is one of the most popular technique used in many large scale gas plants for producing
purified oxygen or purified nitrogen. The output of liquid oxygen produced from the plant can be stored in a
liquid oxygen tank. iquid nitrogen is produced as a by product simultaneously upto 22.2224 purity. Thecryogenic plants are extremely versatile, safe and easy to operate and all the possible product variants that
are produced can be taken as either 8994 liquid oxygen out put or 94 liquid oxygen output directly into
cylinders or 94 liquid nitrogen and 94 liquid oxygen.
!hat is Cryogenic "i#uid$
A refrigerated, severely cold (!39;- to !
-
8/19/2019 Gas Plant Processing
4/36
• Copression of air: This is accomplished by multistage highly efficient air compressor.
• Purification of air: &urification of air is dome by an important component of the gas plant known
as process skid.
• Cooling ( li#uification of air: A highly efficient expansion engine and a refrigeration unit (for
8994 liquid output are used for cooling and liquification.
• Air separation )rectification*: Air separation is done in an air separation unit consisting of
upper ? lower column and special exchangers. The separation air is done by the cryogenic process
and the final output whether a liquid oxygen or liquid nitrogen or both goes to the storage tank.
Benefits of Cryogenic "i#uid Plants
0esides producing pure liquid oxygen and nitrogen, cryogenic liquid plants are used directly in other
processes:
• 6ydrogen recovery
• 6ydrogen purification
• iquid petroleum gas (&1 recovery from refinery off gas
• 7thane and ethylene recovery
• &urification of carbon monoxide
• itrogen purification of ammonia syngas
• atural gas processing for recovering 1 and helium
+#uipent re#uired in Cryogenic "i#uid Plants
• )uction filter
• Air compressor
• &rocess skid
o After cooler with tank
o itrogen cooler with tank
o *oisture separatoro -hilling unit
o 'il absorber
o *olecular sieve battery
o /efrost heater
o 1as+Air+water line as per standard layout on skid
o @ater pump
o $nlet ? outlet water lines
• 7xpansion engine
• Air separation unit
• iquid oxygen pump
• -ooling tower
• @ater softener
Buyer's Guide: Technical specifications
• -apacity (&roduct 'ptions:
o 'xygen liquid 8994, itrogen gas
o 'xygen liquid 94, 'xygen gas 94, itrogen gas
o 'xygen gas at 94, itrogen liquid 94, itrogen gas
• &urity : 'xygen, nitrogen (optional upto 22.2224
• &ower connected
-
8/19/2019 Gas Plant Processing
5/36
• &ower consumed (abt.: 94 gas 94 liquid, 8994 liquid
• &ower supply
• Air capacity
• )tarting pressure
• @orking pressure (abt: 94 gas 94 liquid, 8994 liquid
• )tarting time (after defrost
• )tarting time (after tripping
• Areas required
• Assembly height
• @eight (about
• Air separation column
Cryogenic Nitrogen Plant
)pecifications &rocess
Applications
-ryogenic nitrogen plants are gas plants generating nitrogen using the cryogenic process. -ryogenic plants
http://www.industrialgasplants.com/cryogenic-nitrogen-plant.html#specifications%23specificationshttp://www.industrialgasplants.com/cryogenic-nitrogen-plant.html#process%23processhttp://www.industrialgasplants.com/cryogenic-nitrogen-plant.html#application%23applicationhttp://www.industrialgasplants.com/cryogenic-nitrogen-plant.html#specifications%23specificationshttp://www.industrialgasplants.com/cryogenic-nitrogen-plant.html#process%23processhttp://www.industrialgasplants.com/cryogenic-nitrogen-plant.html#application%23application
-
8/19/2019 Gas Plant Processing
6/36
using cryogenic temperature are used for production of liquid and gaseous nitrogen from atmospheric air.
@hile the cryogenic oxygen plants produce oxygen as the final product, nitrogen is also produced as a by
product in the process. 6owever, there are independent gas plants producing nitrogen alone. $n other words,
the cryogenic air separation units can produce both high purity nitrogen gas as a second product with
oxygen and as a prime product in nitrogen generators, where gas is the final output. 0eing a relative inert
gas, cryogenic nitrogen is used as a protective atmosphere to prevent oxidation.
-ryogenic nitrogen plants represent highly efficient equipment for large!scale nitrogen production with the
nitrogen purity of up to 2!224 pure nitrogen. $n most cases the cryogenic technology of nitrogen production
proves economically feasible and are always considered more advantageous than membrane and
adsorption systems.
Specifications of Cryogenic Nitrogen Plants
A typical cryogenic plant has two modules!a cold box and an warm end container. The cold box consists of a
condenser, the rectification column and heat exchangers. The warm end container is usually equipped with
an air pre!treatment unit, an air compressor, electrical devices and a control system.
Typical specifications for a cryogenic nitrogen plant that a buyer should know without additional purification
and compression are:
• -apacity: 'utput capacity
• &urity: itrogen purity
• &ressure
• Ambient temperature during operation and storage
The Cryogenic Process and Technology
The cryogenic process separates air by using means of rectification. This makes use of the different
evaporation temperatures of the air components. There are inlet filters in the pants which remove dust andother impurities from the air before it enters the air compressor. 6ere the air is compressed to the required
process pressure. $t is then pre!cooled. After moving through a moisture separator, the air enters one of two
molecular adsorbers, where impurities are removed. 6ere, one adsorber is always effective while the other
is being regenerated by residual gas from the separation process.
The processed air is then cooled at a liquefaction temperature in the main heat exchanger and then fed into
the bottom of the rectification column. The pure nitrogen fraction is removed from the top column, then fed
into the product line. -old is supplied in the form of liquid nitrogen ($ from the back!up system. This is
regenerated with an expansion turbine. The pure nitrogen is stored in cylinders or storage tanks and then
distributed.
,lo diagra
-
8/19/2019 Gas Plant Processing
7/36
Applications of Cryogenic Nitrogen Plants
• -hemical and petrochemical industry
o $nerting+purging
o -atalyst regeneration
• 0lanketing
o *etallurgy+1lass industry
o 6eat treatment
o efining
o &urging
o $nerting
• 7lectronic industry
o &urging
o $nerting
o &ackaging
o Air /rying
• ood $ndustry
o packaging
o $nerting
• 'il and gas industry
o itrogen fire fighting
o &ipe!lines blowing
o Air drying
o &ressure testing
o Technological tanks cleaning
o
Cryogenic Oxygen Plant
-ryogenic 'xygen The process 'xygen 1rades
Applications 0uyers 1uide
-ryogenic oxygen plants are oxygen generating plants in the cryogenic process. @e all know that there are
basically two processes used in gas plants to produce pure oxygen!one is the cryogenic process and the
other is the non cryogenic process.
http://www.industrialgasplants.com/cryogenic-oxygen-plant.html#oxygen%23oxygenhttp://www.industrialgasplants.com/cryogenic-oxygen-plant.html#process%23processhttp://www.industrialgasplants.com/cryogenic-oxygen-plant.html#oxygen%23oxygenhttp://www.industrialgasplants.com/cryogenic-oxygen-plant.html#application%23applicationhttp://www.industrialgasplants.com/cryogenic-oxygen-plant.html#buyer%23buyerhttp://www.industrialgasplants.com/cryogenic-oxygen-plant.html#oxygen%23oxygenhttp://www.industrialgasplants.com/cryogenic-oxygen-plant.html#process%23processhttp://www.industrialgasplants.com/cryogenic-oxygen-plant.html#oxygen%23oxygenhttp://www.industrialgasplants.com/cryogenic-oxygen-plant.html#application%23applicationhttp://www.industrialgasplants.com/cryogenic-oxygen-plant.html#buyer%23buyer
-
8/19/2019 Gas Plant Processing
8/36
@hile the cryogenic process is suitable for large scale gas plants as well small si"ed gas plants, the non
cryogenic process involving the &)A technique is more suitable for small si"ed plants. -ryogenic gas plants
are suitable for producing oxygen for industrial and medical uses and available in large, bulky si"es and also
small si"ed cylinders. $n other words, cryogenic oxygen plants are available in low purity which is
approximately 24 and high purity which is almost 22.3B4. There are oxygen!only plants, and multi!product
configurations like oxygen, nitrogen, argon etc.
!hat is Cryogenic ./ygen$
-ryogenic oxygen is oxygen in liquid state and it is very cold. $n cryogenic oxygen plants, oxygen is
produced, stored and maintained in a liquid state at a substantially constant pressure.
The Cryogenic Process
-ommercial oxygen produced in cryogenic gas plants use the cryogenic distillation process originally
developed in 852. This cryogenic process produces oxygen that is 22B4 pure. The steps involved are as
follows:
Copression
• The air is compressed using a multi!stage compressor, which is then passed through a water!
cooled after cooler to condense any water. 0efore compression, air is pretreated to remove
impurities. 'nce the impurities are removed, the air is submitted to fractional distillation, where the
components are separated in several stages. $n the cryogenic process, a cryogenic section is
required to provide the low temperatures required to liquefy the gas components. 'nce the liquid
oxygen is separated, it is purified and stored.
• The air passes through a molecular sieve adsorber, containing "eolite and silica gel!type
adsorbents. These adsorbents adsorbs the carbon dioxide, heavier hydrocarbons, and any
remaining traces of water vapor.
Separating
• Air is separated into its ma%or components in this step. The portion of the pretreated air is diverted
through a compressor, where its pressure is cooled and allowed to expand to nearly atmospheric
pressure. This expansion rapidly cools the air using the cryogenic technique.
-
8/19/2019 Gas Plant Processing
9/36
• The air stream which is part liquid and part gas enters the base of the high!pressure fractionating or
distillation column. As the air moves up the column, it loses additional heat. The oxygen continues
to liquefy, leading to the formation of oxygen!rich mixture in the bottom of the column, and other
gases like nitrogen and argon flow to the top as a vapor. The oxygen at the top is the liquid oxygen
mixture, also known as crude liquid oxygen, which is almost 22.4.
Purifying
The oxygen at the bottom is about 22.4 pure. ewer cryogenic distillation units are used to recover more
of the argon+nitrogen from the low!pressure distillation column, and this improves the oxygen purity to about
22.54. $f higher purity is needed, additional fractionating columns may be added to further refine the oxygen
product.
Distributing
The purified cryogenic oxygen produced is distributed to the end users in gas pipelines from nearby air
separation plants or transported in cylinders and storage tanks to specified destinations. $t is transported in
large, insulated tanks, usually made of two shells and the air is evacuated between the inner and outer shell
to obstruct heat loss.
Diagraatic representation
./ygen Grades at Cryogenic ./ygen Plants
The -ompressed 1as Association, formed in >)A with the intention to work for the development and
promotion of safety standards and safe practices in the industrial gas industry, establishes grading
standards for both gaseous oxygen and liquid oxygen. These standards are based on the amount and type
of impurities present.
1as grades are called Type $ and range from A to . The grade A stands for 22.94 pure and grade stands
for 22.224 pure. iquid grades are called Type $$. These also range from A to . 6owever, the types and
amounts of impurities in liquid grades are different from the gas grades. The most commonly produced
grades of oxygen are Type $ 1rade 0 and 1rade - and Type $$ 1rade - which is 22.4 pure. They are used
in steel making and in the manufacture of synthetic chemicals.
Applications of Cryogenic ./ygen
• -ombustion
http://var%20%20pop_it%3Dwindow.open%28%27gifs/cryo-oxygen-b.jpg','subwindow','toolbar=no,location=no,status=yes,scrollbars=yes,menubar=no,resizable=yes,wi%20dth=560,height=360')
-
8/19/2019 Gas Plant Processing
10/36
• 1lass industry
• *etal fabrication
• &ulp and paper industry
• -hemical industry
• *edical
• @aste water treatment.
+#uipent re#uired in cryogenic o/ygen plants
• )uction ilter
• Air -ompressor
• After -ooler
• -hilling >nit
• 'il Absorber
• *oisture )eparator
• *olecular )ieve 0attery
• 7xpansion 7ngine
• Air )eparation -olumn
• iquid 'xygen &umps
Buyer's guide
• Si2e: $arge& !edium& Small&
"ortable
• +apacity
• "urity
• ir +apacity
• "ower +onnected
• "ower +onsumed
• "ower Supply
• Starting pressure
• 1orking "ressure
• reas Re%uired
• ssembly 3eight
• 1eight
• ir Separation +olumn
Hydrogen Plants
*anufacturing &rocess 6ydrogen from ossil uels 6ydrogen from enewables
0iological &rocess Ammonia -racking Applications
http://www.industrialgasplants.com/hydrogen-plant.html#manufacturing%23manufacturinghttp://www.industrialgasplants.com/hydrogen-plant.html#fossil%23fossilhttp://www.industrialgasplants.com/hydrogen-plant.html#renewables%23renewableshttp://www.industrialgasplants.com/hydrogen-plant.html#biological%23biologicalhttp://www.industrialgasplants.com/hydrogen-plant.html#ammonia%23ammoniahttp://www.industrialgasplants.com/hydrogen-plant.html#applications%23applicationshttp://www.industrialgasplants.com/hydrogen-plant.html#manufacturing%23manufacturinghttp://www.industrialgasplants.com/hydrogen-plant.html#fossil%23fossilhttp://www.industrialgasplants.com/hydrogen-plant.html#renewables%23renewableshttp://www.industrialgasplants.com/hydrogen-plant.html#biological%23biologicalhttp://www.industrialgasplants.com/hydrogen-plant.html#ammonia%23ammoniahttp://www.industrialgasplants.com/hydrogen-plant.html#applications%23applications
-
8/19/2019 Gas Plant Processing
11/36
0uyer#s 1uide
0ound in organic matter and in water, hydrogen constitutes almost =4 of the earth#s surface and hence the
most abundant of all the chemical elements. 6ydrogen gas plants, available in small as well as in large
tonnage si"es, are hydrogen generating systems, used widely as a fuel and in various industrial purposes.
or many manufacturers and suppliers dealing with gas plants, supplying hydrogen gas plants involveconceptual design, procurement, detailed engineering, fabrication, construction, start!up, including
distribution and operator training.
%anufacturing Process of 0ydrogen
There are a wide range of sources by which hydrogen in produced in gas plants, which we are discussing
below:
0ydrogen fro ,ossil ,uels
• Stea 1eforing:
A very common method of producing hydrogen, steam reforming implied the use of thermal energy
which helps in separating hydrogen from the carbon components in methane and methanol. $n other
words a hydrocarbon gas like methane (-6C is combined with steam at high temperatures and
pressures in the presence of a catalyst which in turn produces hydrogen and -'<
The hydrogen produced is used in the manufacturing of fertili"ers, chemicals and also in the
improvement of the quality of petroleum products. This is considered to be the most cost effective
method of producing hydrogen.
• Partial ./idation:
Another process of producing hydrogen from fossil fuels is by the process of reaction of heavier
hydrocarbons like coal, oil, and some biomass products with steam.
0ydrogen fro 1eneables
@hen we talk about renewable energy, it implies the energy derived from energy sources like wave, wind,
solar, tidal etc. which is naturally replenished and cannot be exhausted. /ifferent processes used in
renewable energy to produce hydrogen is discussed below:
http://www.industrialgasplants.com/hydrogen-plant.html#buyer%23buyerhttp://www.industrialgasplants.com/hydrogen-plant.html#buyer%23buyer
-
8/19/2019 Gas Plant Processing
12/36
• +lectrolysis
0y separating the elements of water!6 and oxygen ('!by charging water with an electrical current
is referred to as electrolysis and this is one popular method of producing hydrogen. Adding an
electrolyte like salt helps in making better the conductivity of the water and increases the efficiency
of the process. The chemical bond between the hydrogen and oxygen breaks with the electric
charge and separates the atomic components, which create charged particles called ions. The ions
are of two types!the anode, which is positively charged, and the cathode, which is negatively
charged. The anode attracts oxygen and hydrogen gathers at the cathode.
• Stea +lectrolysis
A variation of the conventional electrolysis process, in steam electrolysis, instead of electricity the
energy needed to split the water is added as heat. At
-
8/19/2019 Gas Plant Processing
13/36
Aonia Crac2ing
Another method used for the production of hydrogen is ammonia cracking process. This process is highly
recommendable in conditions where ammonia is used as a raw material, nitrogen does not function as an
impurity ? hydrogen is used as a reducing atmosphere
Applications of 0ydrogen Gas Plants
• 1efinery ( Petrocheicals: &etroleum and petrochemical manufacturers require a reliable
supply of high!quality hydrogen for their operations.
• .ils 0ydrogenation: 6ydrogenation of sugars, natural oils is very important in the production of
a variety of consumer goods like cooking oils, sweeteners, and cleaning products.
• %etals 0eat Treating: A hydrogen!containing atmosphere is required in many metals heat
treating processes require to produce a high quality finished part.
• Glass %anufacturing: $t is very essential to have a stable and consistent hydrogen supply in
meeting the strict product quality standards in the float glass industry.
• +lectronics:/ue to the sensitivity in electronics manufacturing, on!site gas plants producing
hydrogen provides several benefits over alternative solutions.
• Transportation 1efueling: As the demand for alternative energy sources increases, the ability
to produce hydrogen fuel economically is becoming increasingly important.
• !elding: 6ydrogen gas is required for welding and cutting.
• Cheical 3ndustry: 6ydrogen gas acts as synthesis gas for ammonia synthesis in the chemical
$ndustry.
• Paper ( Te/tiles
• Steel 3ndustry
• ,uel Cells
Buyer's Guide
Things to know before purchasing hydrogen gas plants are
• 3ydrogen purity
• +apacity
• "roduced gas pressure
• ire ha2ard
• "lant si2e
• "rocess description
• "lant description
• "lant control instruments
• "lant performances
Nitrogen Plant
-ryogenic &rocess on cryogenic process 7quipment
http://www.industrialgasplants.com/nitrogen-plant.html#cryo%23cryohttp://www.industrialgasplants.com/nitrogen-plant.html#non-cryo%23non-cryohttp://www.industrialgasplants.com/nitrogen-plant.html#Equipment%23Equipmenthttp://www.industrialgasplants.com/nitrogen-plant.html#cryo%23cryohttp://www.industrialgasplants.com/nitrogen-plant.html#non-cryo%23non-cryohttp://www.industrialgasplants.com/nitrogen-plant.html#Equipment%23Equipment
-
8/19/2019 Gas Plant Processing
14/36
Types 0uyers 1uide
itrogen gas plants are nitrogen generating system which can be small, portable si"e to large tonnage gas
plants, like oxygen plants, used for refining, chemical processing and other applications. $nfact, in almost all
oxygen plants, nitrogen is also produced at the same time.
itrogen (
-
8/19/2019 Gas Plant Processing
15/36
liquid is about 394 nitrogen and C94 oxygen and known as the Fich iquidF. As nitrogen is more
volatile it rises to top of the lower column and it becomes liquefied because of the cold it gets from
the condenser.
• Air Separation: inal separation is attained in the upper column. As the rich liquid entering the
middle of the upper column flows down, nitrogen evaporates and oxygen continues as liquid. The
liquid nitrogen which is also known as the poor liquid enters the top of the column and while flowingdown, it comes in contact with any evaporating 'xygen and condenses the same into liquid.
itrogen being volatile becomes a gas. The entire gaseous nitrogen is piped out through heat
exchangers from the top of the column. 1enerally the purity of 'xygen will be 22.4 and itrogen
about 234, when the plant is operated exclusively for oxygen production.
• ,illing of "i#uid 5Gas Nitrogen: The last step is the filling of purified nitrogen into pumps and
cylinders .
Non Cryogenic %anufacturing Process
PSA Process
>sing molecular sieves separation technique, the nitrogen generator produces nitrogen gas from
atmospheric air. The &)A process for nitrogen generation is similar to that of oxygen but carbon molecular
sieve (-*) is used instead of "eolite molecular sieve (G*). /ue to the adsorption properties of -*), it is
possible to produce nitrogen by charging two adsorber vessels with compressed air one after the other.@hile one vessel adsorbs, the other vessel is used in regenerating by pressure reduction. $n other words,
when compressed air is passed, nitrogen comes out as product gas from one vessel while the other vessel
is simultaneously regenerated by de!pressurisation to atmospheric pressure.
%ebrane Nitrogen Syste
0y using membrane technology, compressed air is provided from air compressor to separate nitrogen from
air. A feed air cleaning system is available in the membrane separator to provide clean air, free from solid
particles, oil and water droplets. The clean air will lead to higher efficiency nitrogen production and ensure
long life of the membranes.
+#uipent re#uired in Nitrogen Plants
• ir compressor system
• !oisture separator
• (4 Separation !embrane !odules
• (4 *as anks
• ir filter
• dsorber
• )xpander
• (itrogen pressure and flow regulator
Standard Applications of Nitrogen Gas Plants
• -hemical *anufacturing (*aterial Transfer, 0lanketing
• 7lectronics ()torage, @ave )oldering, urnace Application
-
8/19/2019 Gas Plant Processing
16/36
• ood &rocessing
• ood &ackaging
• aser -utting
• Tire illing
• &lastics ($n%ection *olding
• &harmaceuticals (&ackaging, 0lanketing
• 6eat Treatment (errous ? on!errous *etals
Types of Nitrogen Plants
/epending on the manufacturing process, nitrogen plants can be classified as follows:
• %ebrane Nitrogen Plants: The most automated gas plants designed for production of
nitrogen from atmospheric air.
• Adsorption Nitrogen Plants: Automated systems designed for gaseous nitrogen production
from air.
• Cryogenic Nitrogen Plants: These are cryogenic temperatures based plants designed for
production of liquid and gaseous nitrogen from atmospheric air.
• %obile Nitrogen Stations: *obile stations used for air!to!nitrogen production are specially
designed for operation in various climatic "ones. H *obile nitrogen compressor stations: These are
self!operated and carried nitrogen compressor stations for high!pressure nitrogen recovery.
Buyer's guide
Technical specifications to consider for purchasing nitrogen gas plants are
• Si2e: $arge& !edium& Small& "ortable
• +apacity: "ressure
• "urity
• "ower +onsumed• "ower Supply
• "ower +onnected
• Starting pressure
• 1orking "ressure
• ir +apacity
• Starting ime 5fter 6efrost7
• Starting ime 5fter ripping7
• reas Re%uired• ssembly 3eight
• 1eight
• ir Separation +olumn
Oxygen Plant
-
8/19/2019 Gas Plant Processing
17/36
-ryogenic &rocess &)A process 7quipment
Types Applications 0uyers 1uide
'xygen plants are cost effective and safe oxygen producing system that range from small portable units to
large si"ed gas plants. The main purpose of oxygen plants is to produce industrial and medical oxygen up to
22.24 purity. The oxygen gas plants are used to serving markets for bottling cylinders, bra"ing of metals,
industrial gas cutting of steel, production of steel glass and ampule industry, used in petrochemical industry,
oil ? gas industry, animal husbandry and used for fabrication.
The oxygen plant units commonly operate according to cryogenic technology which is the preferred
technique for large si"ed plants or through non cryogenic technology!&)A+E&)A+E)A (&ressure swing
adsorption+Eacuum pressure swing adsorption+Eacuum swing adsorption, preferable for small and medium
si"ed plants. 6owever, it is basically the specifics of the application which decide which technology will be
most economical. The oxygen plant can also be used to produce nitrogen and argon from the air at the
same time. These oxygen plants can be designed as per their application requirements or as per thespecifications of customers.
%anufacturing Process )Cryogenic Process*
The process of producing oxygen in oxygen gas plants involves the following steps:
Step 6: Copression of atospheric air
$n the first stage of the production process, the free saturated air is sucked from atmosphere with the help of
a highly efficient dry!type suction filter or an air compressor.
Step 7: Purification of air
The next step involves the cleaning of air by removing moisture, oil traces, carbondioxide and other impure
products in the process air. $n the cryogenic technology, the compressed air is chilled in a chilling unit and
http://www.industrialgasplants.com/oxygen-plant.html#cryogenic%23cryogenichttp://www.industrialgasplants.com/oxygen-plant.html#psa%23psahttp://www.industrialgasplants.com/oxygen-plant.html#equip%23equiphttp://www.industrialgasplants.com/oxygen-plant.html#types%23typeshttp://www.industrialgasplants.com/oxygen-plant.html#app%23apphttp://www.industrialgasplants.com/oxygen-plant.html#buyers-guide%23buyers-guidehttp://www.industrialgasplants.com/oxygen-plant.html#cryogenic%23cryogenichttp://www.industrialgasplants.com/oxygen-plant.html#psa%23psahttp://www.industrialgasplants.com/oxygen-plant.html#equip%23equiphttp://www.industrialgasplants.com/oxygen-plant.html#types%23typeshttp://www.industrialgasplants.com/oxygen-plant.html#app%23apphttp://www.industrialgasplants.com/oxygen-plant.html#buyers-guide%23buyers-guide
-
8/19/2019 Gas Plant Processing
18/36
transfered to a moisture separator where the condensed moisture gets separated before entering into
*olecular )ieve 0attery. 0efore that the air is passed through an oil absorber to remove oil.
Step 8: Cooling of air
The process air before liquefication in the gas plant is cooled to below!"ero temperature (cryogenic. After
pre cooling, the main portion of the process air enters the expansion engine through the heat exchanger .
The temperature of the air further drops down, somewhere about !83 deg - by the expander. est of air
enters into a highly efficient expansion engine, where the air is cooled further down to (!89 deg - before
entering into bottom column. The liquefied air collected at the bottom column from both these streams is
known as Frich liquidF.
Step 9: Separation of air
After the colling, the air enters the air separation unit where the air is converted into liquid air by deep
cooling at low or cryogenic temperatures and is separated into liquid oxygen and nitrogen.
Step : ,illing of o/ygen
The final stage in the process is the transport of liquid oxygen from the condenser to the cryogenic liquid
oxygen pump for filling gas cylinders.
%anufacturing process )PSA process*
&)A technology is another technique used in producing oxygen but it is preferred for small si"ed or portable
plants. The technique is based on the selective adsorption process of gas molecules under pressure on the
surface of highly porous and efficient adsorbent, usually "eolite based molecular sieve. $n &)A )ystem,
when compressed air is passed through "eolite based molecular sieve, the molecules of oxygen, moisture ?
other impure gases are adsorbed on the surface and oxygen which is not adsorbed comes out.
+#uipent 1e#uired in ./ygen Plants
• *olecular 0attery
• &urger
• &ressure )kid
• 7xpander
• -hilling >nit
• 'il Adsorber
-
8/19/2019 Gas Plant Processing
19/36
• 1as -ompressor
Types of ./ygen Plants
/epending on the manufacturing process, oxygen plants can be classified as follows:
• Adsorption ./ygen Plants: 6igh!performance gas plants developed for oxygen production
from atmospheric air and cylinder filling.
• %ebrane ./ygen Plants: ully automated membrane gas plants specially developed for air
oxygenation.
• Cryogenic ./ygen Plants: 1as plants for deep air free"ing specially designed to produce both
liquid and gaseous oxygen from air.
• %obile ./ygen Stations: These are transportable gas stations used to deploy a complete
oxygen production cycle with the cylinder filling option.
Application of ./ygen Plant
The basic property of oxygen is that it makes combustion possible, and it is this property which makes it
highly usable in various industrial applications. 0eing the largest volume industrial gas, oxygen plants are
used in the following industries :
• &etroleum ecovery and efining
• -hemical $ndustry
• )teel *anufacturing $ndustry
• &ulp and &aper $ndustry
• 1lass *anufacturing
• abrication industry
• *edical industry
Buyer's Guide
Technical specifications to consider for purchasing oxygen gas plants are:
• Si2e: $arge& !edium& Small&
"ortable• +apacity: xygen "ressure 5upto7
• "urity
• "ower +onnected
• "ower +onsumed
• "ower Supply
• ir +apacity
• 1orking "ressure
• Starting ime 5fter 6efrost7
• Starting ime 5fter
ripping7
• reas Re%uired
• ssembly 3eight
• 1eight
• ir Separation +olumn
-
8/19/2019 Gas Plant Processing
20/36
PSA Oxygen Gas Plant
&rocess eatures E&)A unit
0enefits Applications
&)A oxygen gas plants are plants producing oxygen using the &)A process. 'xygen is used for various
industrial applications and hence needs to be produced in large volumes. There are usually two methods to
do this: cryogenic process and the &)A process. The &)A technology has today emerged as a very popular
technique for the production of commercial production of oxygen gas and suited for both small and mediumsi"ed units. The &)A process is very useful for small applications like oxygen production for asthma
patients.
!hat is PSA$
&)A stands for pressure swing adsorption. $t is dependent on air being filtered through aluminosilicate
minerals, called as "eolites. $n the &)A process, nitrogen gas is adsorbed into the "eolites and oxygen (and
argon pass through. $t is a technology in which some gas species are separated from a mixture of gases
under pressure. The &)A technique is very environment friendly and can also remove other gases such as
carbon dioxide from industrial waste gas streams.
The process
http://www.industrialgasplants.com/psa-oxygen-plant.html#process%23processhttp://www.industrialgasplants.com/psa-oxygen-plant.html#feature%23featurehttp://www.industrialgasplants.com/psa-oxygen-plant.html#vpsa%23vpsahttp://www.industrialgasplants.com/psa-oxygen-plant.html#benefits%23benefitshttp://www.industrialgasplants.com/psa-oxygen-plant.html#app%23apphttp://www.industrialgasplants.com/psa-oxygen-plant.html#process%23processhttp://www.industrialgasplants.com/psa-oxygen-plant.html#feature%23featurehttp://www.industrialgasplants.com/psa-oxygen-plant.html#vpsa%23vpsahttp://www.industrialgasplants.com/psa-oxygen-plant.html#benefits%23benefitshttp://www.industrialgasplants.com/psa-oxygen-plant.html#app%23app
-
8/19/2019 Gas Plant Processing
21/36
• Copression of feed air and conditioning: >sing an air compressor, the ambient air gets
compresses, dried by an air dryer and then filtered before entering the process vessels.
• Adsorption: The next step in the &)A process of producing oxygen is the adsorption process.
The process removes impurities and produces almost 8994 pure oxygen. The pre!treated air
passes through a vessel filled with Geolite *olecular )ieve (G*). 6ere nitrogen and other gases
gets adsorbed and most of the oxygen pass and this continues till G*) is fully exhausted.
• Desorption: The saturated G*) is regenerated. This is done by pressure reduction, using a
simple pressure release system. This is after the adsorption process. The waste stream moves into
atmosphere. @hile regenerated adsorbent is purged with oxygen. This is again used for the
generation of oxygen.
• 1ecei4er: The adsorption and desorption process take place at equal time intervals, and there is
continuous generation of oxygen. 0y using a connected oxygen receiver, a constant product flow
and purity is maintained, which can store the oxygen with purities up to 24. inally, the plant
produces a constant flow of on!site produced oxygen.
,eatures of PSA ./ygen Plants
>sually the design of &)A oxygen plants rely on many factors like:
• Geolite bed packing
• 0ed length
• /iameter
• ate of infeed air
$n medical oxygen &)A plants, power efficiency is not given much preference compared to robustness,
process stability and oxygen purity. $n large si"ed &)A plants, the &)A process is only cost effective while
operating at maximum separation efficiency.
;PSA ./ygen Plant nit
>sing E&)A (vacuum pressure swing adsorption, oxygen is produced in small demands for various
applications. A typical E&)A unit is shown below:
Benefits of Psa Plants
-ompared to other processes used in gas plants, the &)A process has certain benefits:
• 6igh operational efficiency
• owers power costs
• ull safety
-
8/19/2019 Gas Plant Processing
22/36
• o ha"ards involved as with bulky gas cylinders
• ow pressure drops
• 6igh output pressures
• $ndependent on!site production
Applications of PSA ./ygen Plants
• )teel industry
• &ulp and paper industry
• 1lass and enamel industry
• /rinking water supply
• -hemical industry
• 0iotechnology industry
• @aste water treatment and waste disposal ind
What is cryogenic gas
-ryogenic gas plants have today emerged in the current market scenario as the most efficient and cost
effective technology of producing and distributing pure gases like oxygen and nitrogen. The technology is
perfect for large si"ed gas plants. The best feature of these gas plants is that they can produce liquid
products.
-ryogenic gases are liquefied gases at standard temperature and pressure. They are kept in their liquid
state at very low temperatures. The word FcryogenicsF in 7nglish means Fthe production of icy coldF.
-ryogenics in physics means the study of the production of extremely low temperatures (below !89 I-,
!
-
8/19/2019 Gas Plant Processing
23/36
• A little quantity of liquid can expand into very large volumes of gas.
-ryogenic gases are very popular and they are used as fuels, oxidi"ers and refrigerants. These gases are to
be stored properly to get their maximum usage. $n poorly insulated containers, it is very likely that some
cryogenic gases actually condense the surrounding air, forming a liquid air mixture. That is the reason they
should be held in special containers like /ewar flasks, which are generally about 8.5 m (3 feet tall and 28.cm (D feet in diameter. or commercial applications they are stored in giant tanks. $n museums, cryogenic
gas is stored in smaller vacuum flasks fitted in a protective casing. There are cryogenic transfer pumps used
on 1 piers. These pumps are used to transfer iquefied atural 1as from 1 -arriers to 1 storage
tanks.
-ryogenic gas also has some ha"ards associated with it like as they may be flammable, as in 6ydrogen,
&1 or they may be oxidi"ers, as in luorine, 'xygen and hence they must be carefully used.
A quick recap • +ryogenic gas is a gas formed at 0ery low temperature 5below 89+7.
• +ommonly used cryogenic materials is li%uid nitrogen and li%uid helium.
• he gas is produced through a process of compression and cooling.
•
-
8/19/2019 Gas Plant Processing
24/36
"i#uid ./ygen
-omprising sed primarily in
the aerospace, submarine and gas industry, liquid oxygen ('K is the liquid form of oxygen, which is pale
blue in color and extremely cold. iquid oxygen has a boiling point of !
-
8/19/2019 Gas Plant Processing
25/36
• =rypton
• >enon
• 3ydrogen
• $"*
• cetylene
• $i%uid oxygen
Storing of Cryogenic Gas
-ryogenic gases are needed to be stored in special containers, which are usually thermally insulated
containers, specifically designed to bear rapid temperature changes and extreme differences in temperature.
>sually the containers are designed in such a way so that they have few of the features as given in the
figure below:
Storage containers
)ome of the popular storage containers of cryogenic gases are as follows:
Dear flas2s
/ewar flask, named after its inventor )ir Lames /ewar in 852
-
8/19/2019 Gas Plant Processing
26/36
dispensing the cryogenic liquid. As a backup protection these cylinders also have pressure!control valves
with a frangible or bursting disk.
There are three main types of cryogenic liquid cylinders which are designed for storing:
• 'nly liquid
• 'nly gas
• iquid or gas
"i#uid cylinders ha4e to priary ad4antages:
• At relatively low pressure compared to compressed gas cylinders, these cryogenic cylinders can
hold a large volume of gas.
• These cylinders are an easy source of cryogenic liquid that can be easily handled.
Cryogenic products that are stored in li#uid cylinders are:
• (itrogen
• rgon
• xygen
• 3elium
• 3ydrogen
• (itrous oxide
• +arbon dioxide
• =rypton
• !ethane
• >enon
• (eon
@hile nitrogen, argon, oxygen, helium, hydrogen are stored in their liquid states, nitrous oxide and carbon
dioxide are kept as refrigerated liquids, but at higher temperature and pressure. These cylinders are well
insulated but at times the extremely low temperatures of the cryogenic liquids can lead to constant heat leak
and vapori"ation. The cryogenic product when not used will lead to pressure in the cylinder and often vent
via the container#s pressure relief device. 6owever, this is a normal and safe function of the cylinder.
Tan2s
Tanks are large double!walled, insulated storage tank, spherical or cylindrical in shape used for storing
cryogenic liquids or gases. Tanks are large storing containers for cryogenic gases, capacities ranging from
approximately hundreds of gallons to thousands of barrels. They are designed in such a way so that they
can be easily mounted in fixed locations as stationary vessels or on truck chassis or railroad car for easy
transportation. The pressure inside the tank is kept normal. The space between inner and outer surface is
vacuum and there are safety relief valves to protect the tanks.
Soe useful tips to consider for storing and transporting cryogenic li#uids:
-
8/19/2019 Gas Plant Processing
27/36
• 7nsure that all incoming containers are not damaged before storing.
• Always use the correct name for all products. or instance, you should never call Fliquid oxygenF as
Fliquid airF. 'r if the oxygen is in a mixture of other gases, refer to it as Foxygen mixtureF or
Fmedium purity liquid oxygenF.
• /ewar flasks should always be kept covered with a loose fitting cap. This helps in preventing air or
moisture from entering the container and at the same time allows pressure to escape.
• *ake use of only the plug or stopper supplied with the container.
• 1lass dewar flasks should not be used to store combustible or oxidi"ing cryogenic liquids.
• ever let ice form in the neck of flasks.
• /o not store containers in those areas where they have a chance to come in contact with moisture.
7nsure that storing vessels are insulated from any sources of heat.
• /o not store liquid oxygen containers on asphalt, oil soaked gravel or wood.
• $t is better to use concrete or clean gravel under storage areas.
• )tore all cryogenic liquid containers in well!ventilated areas.
• 6andle liquid cylinders carefully by avoiding rolling, dropping or tipping them on their sides.
• @hen transferring cryogenic liquids from one flask to another, always cool the receiving dewar flask
before filling it.
• )tart filling liquids slowly so as to allow the vapori"ation to chill the receiving container. After the
liquid boiling and vapori"ation have declined, fill the container at the normal rate.
• >se an appropriate filling device when pouring cryogenic liquids.
• ill storage containers only with liquids they are designed to hold.
A quick recap
ll cryogenic products must be properly stored and transported.he containers should bedesigned in such a way so that they can bear rapid temperature changes and also
differences in temperature. hat is why most containers are thermally insulated. Some of
the popular storage containers used for storing cryogenic gases are as follows:
• $i%uid dewar flasks
• $aboratory li%uid dewar flasks
• $i%uid cylinders
• anks
Cryogenic Air Separation
-
8/19/2019 Gas Plant Processing
28/36
-ryogenic Air )eperation &rocess low diagram Air )eparation )teps A quick recap
-ryogenic air separation process is one of the most popular air separation process, used frequently in
medium to large scale plants. $t is the most preferred technology for producing nitrogen, oxygen, and argon
as gases and+ or liquid products and supposed to be the most cost effective technology for high production
rate plants. $n today#s market scenario, all liquefied industrial gas production plants make use of cryogenic
technology to produce liquid products.
!hat is cryogenic air separation process$
-ryogenic air separation is a process to produce highly purified gases or liquids and it is done by taking
large volumes of air from the atmosphere, which is then compressed, cooled, liquefied. This is thenseparated into its ma%or components by distillation. After the air is compressed, impurities must be removed.
There are different variations arising from differences in user requirements in the cryogenic air separation
cycles to produce industrial gas products. The cycle of processing depends on:
• 6ow many products are required (whether simply oxygen or nitrogen, both oxygen and nitrogen, or
nitrogen, oxygen and argon.
• equired purities of the products.
• 1aseous product delivery pressures.
• astly whether the products need to be stored in liquid form.
$n the cryogenic gas processing, various equipment is used like the distillation columns, heat exchangers,
cold interconnecting piping etc. which operate at very low temperatures and hence must be well insulated.
These items are located inside sealed Fcold boxesF. -old boxes are tall structures with either round or
rectangular cross section. /epending on plant type, si"e and capacity, cold boxes may have a height of 8
to 39 meters and < to C meters on a side.
Cryogenic air separation flo diagra
The cryogenic air separation flow diagram given below does not represent any particular plant and shows in
a general way many of the important steps involved in producing oxygen, nitrogen, and argon as both gas
and liquid products.
http://www.industrialgasplants.com/cryogenic-air-separation.html#cryo%23cryohttp://www.industrialgasplants.com/cryogenic-air-separation.html#process%23processhttp://www.industrialgasplants.com/cryogenic-air-separation.html#flow%23flowhttp://www.industrialgasplants.com/cryogenic-air-separation.html#steps%23stepshttp://www.industrialgasplants.com/cryogenic-air-separation.html#quick%23quickhttp://www.industrialgasplants.com/cryogenic-air-separation.html#cryo%23cryohttp://www.industrialgasplants.com/cryogenic-air-separation.html#process%23processhttp://www.industrialgasplants.com/cryogenic-air-separation.html#flow%23flowhttp://www.industrialgasplants.com/cryogenic-air-separation.html#steps%23stepshttp://www.industrialgasplants.com/cryogenic-air-separation.html#quick%23quick
-
8/19/2019 Gas Plant Processing
29/36
Steps in Cryogenic Air Separation
• ,irst Step: The first step in any cryogenic air separation plant is filtering and compressing air.
After filtration the compressed air is cooled to reach approximately ambient temperature by passing
through air!cooled or water!cooled heat exchangers. $n some cases it is cooled in a mechanical
refrigeration system to a much lower temperature. This leads to a better impurity removal, and also
minimi"ing power consumption, causing less variation in plant performance due to changes in
atmospheric temperature seasonally. After each stage of cooling and compression, condensed
water is removed from the air.
• Second Step: The second step is removing the remaining carbon dioxide and water vapor, which
must always be removed to satisfy product quality specifications. They are to be removed before
the air enters the distillation portion of the plant. The portion is that where the very low temperature
can make the water and carbon dioxide to free"e which can be deposited on the surfaces within the
process equipment. There are two basic methods to get rid of water vapor and carbon dioxide !
molecular sieve units and reversing exchangers.
• Third Step: The third step in the cryogenic air separation is the transfer of additional heat against
product and waste gas so as to bring the air feed to cryogenic temperature. The cooling is usually
done in bra"ed aluminum heat exchangers. They let the heat exchange between the incoming air
feed and cold product and waste gas streams leave the air separation process. The very cold
temperatures required for distillation of cryogenic products are formed by a refrigeration process
comprising expansion of one or more elevated pressure process streams.
• ,ourth Step: This step involves the use of distillation columns to separate the air into desired
products. or example, the distillation system for oxygen has both FhighF and FlowF pressure
columns. itrogen plants can have one or two column. @hile oxygen leaves from the bottom of the
distillation column, nitrogen leaves from the top. Argon has a boiling point similar to that of oxygen
and it stays with oxygen. $f however high purity oxygen is needed, it is necessary that at an
intermediate point argon must be removed from the distillation system. $mpure oxygen produced in
the higher pressure distillation column is further purified in the lower pressure column. &lants which
produce high purity oxygen, nitrogen or other cryogenic gases require more distillation stages.
http://var%20%20pop_it%3Dwindow.open%28%27gifs/generic-air-seperation-b.jpg','subwindow','toolbar=no,location=no,status=yes,scrollbars=yes,menubar=no,resiz%20able=yes,width=550,height=430')
-
8/19/2019 Gas Plant Processing
30/36
• ,ifth Step: The fifth step involves refrigeration which is formed at cryogenic temperature levels.
efrigerations compensate for imperfect heat exchange and for heat leak into the cold equipment.
The refrigeration cycle is almost similar like the one used in home and automobile air conditioning
systems. 'ne or more elevated pressure streams are reduced in pressure, which chills the stream.
To maximi"e chilling, the pressure expansion or reduction takes place inside an expander. 1aseous
products usually come out from the plant at relatively low pressures. $n general, the lower thedelivery pressure, the higher the plant efficiency. $t is always cost effective to produce the cryogenic
gas at low pressure and use a blower or compressor to achieve required delivery and gaseous
storage pressures.
A quick recap
+ryogenic air separation process depends in boiling points differences to separate and purify products. ll cryogenic processes include these steps:
• iltering and compressing air.
• Remo0ing the contaminants.
• +ooling the air to 0ery low temperature.
• 6istilling the air to produce desired products.
• 1arming in heat exchangers gaseous products and waste streams that also cool
the incoming air stream
Cryogenic Gas Haards
0ealth ha
-
8/19/2019 Gas Plant Processing
31/36
cryogenic gases are considered to be of low toxicity, but still they can lead to specific health
problems. )ome gases like carbon monoxide, fluorine, and nitrous oxide are toxic and hence it is
advisable to check the properties of the gases that are being used. or example, liquid carbon
monoxide can generate large quantities of carbon monoxide gas, which can cause death almost
immediately.
,laability5+/plosion ha
-
8/19/2019 Gas Plant Processing
32/36
$f this confined fluid is released all of a sudden, a significant thrust is experienced. 'ver!
pressuri"ation of cryogenic gas occurs when during the phase of change from liquid to gas is not
vented properly. The vapori"ation of cryogenic fluids produce large volumes of gas. A container
with inadequate pressure relief will lead to accumulation of pressure till the container ruptures,
which leads to serious in%ury.
• %aterials and construction ha
-
8/19/2019 Gas Plant Processing
33/36
0o to pre4ent ha
-
8/19/2019 Gas Plant Processing
34/36
cylinders are allowed for liquid hydrogen. ever allow any spilling of hydrogen it can create a flammable
cloud.
A quick recap o a0oid unnecessary ha2ards while handling or storing cryogenic li%uids& some handy
tips are gi0e below:
• lways wear personal protecti0e e%uipment while handling cryogenic gases.
• nly trained and %ualified personal should be allowed to handle& transport or
storing cryogenic gases.
• "roper storage is essential for such gases.
• +ylinders should not be dragged or carried.
• +ontainers should not be used for other purposes except for storing the specified
gas.
• !agnets should not be used for lifting cylinders.
• bser0e containers for loss of insulated 0acuum.
• ll cryogenic storage e%uipment must ha0e proper pressure relief 0ent system so
as to a0oid explosion or o0er pressuri2ation etc
Non!cryogenic Air Separation
1as processing or air separation is a very old technology of science involving the separation of air and the
identification of oxygen as an atmospheric component. )uch a process owes its origin with the origin of
-
8/19/2019 Gas Plant Processing
35/36
chemistry. There are basically two basic technologies of air separation: -ryogenic air separation and on
cryogenic air separation.
@hile the cryogenic technique is a traditional method, the non!cryogenic air separation is however a very
new technology. on cryogenic air separation was developed during the 82=9s. @hile cryogenic gas
separation requires large si"ed plants for its processing, the non cryogenic process is considered to be aconvenient, efficient, and economical method to buying gas in high pressure cylinders or for purchasing bulk
liquid products to be vapori"ed. This process is preferable for many small scale users of oxygen or nitrogen.
!hat e/actly is Non Cryogenic Separation$
The traditional method of producing nitrogen and oxygen gases is cryogenic air separation which involves
the process of cooling air in large si"ed plants to several hundred degrees below "ero in order to separate
the component gases. on!cryogenic air separation is however a very new technology that requires air to
force through through special materials that selectively pass or retain the oxygen or nitrogen. The physical
properties of the gases other than the temperature like molecular si"e and mass are exploited in non
cryogenic air separation process to produce discrete and refine elements of air at close!to!atmospheric
temperature. 'perating at near!ambient temperature, these are then used to produce commercially valuable
gaseous products like oxygen and nitrogen.
There are three main technologies involved in non cryogenic process. They are
• &ressure )wing Adsorption (&)A used in nitrogen and oxygen generators
• Eacuum!&ressure )wing Adsorption (E&)A used in oxygen generators and
• *embrane )eparation, used to produce nitrogen gas.
@e will discuss in details the three processes in the section:
•
Types of non!cryogenic air separation
Ad4antages of Non Cryogenic Separation Processes
• The non cryogenic technique is much smaller in si"e than cryogenic plants
• The basic advantage is that it can be placed directly on the customer#s site
• They are efficient and economical choices when demand is relatively small and when very high
product purity is not required
• They are compact
• They can operate at near!ambient temperature and pressure
• 'nce installed, they can be brought on!line in less than D9 minutes.
Conclusion
on cryogenic gas processing is growing up in recent years though it has not been able to completely
displace other existing technologies. The process is gradually gaining market share in those applications
where it has a clear economic or technical advantage. 0oth technology!push and market!pull factors have
contributed to the running of non separation process centered on &)A, E&)A or membrane technology. or
many manufacturers and suppliers, these non!cryogenic gas separations must play against the long
established cryogenic separations involved in bulk gas business.
http://www.industrialgasplants.com/noncryogenic-gas-types.htmlhttp://www.industrialgasplants.com/noncryogenic-gas-types.html
-
8/19/2019 Gas Plant Processing
36/36
on!cryogenic gas processes are on the way to altering the economics of certain processes and expanding
the markets, applications, and uses of gases. The separation of air into oxygen, nitrogen, natural gas
purification, hydrogen recovery will become increasingly important across a wide spectrum of very specific
applications. >sing non!cryogenic separations all types of gas streams can be processed. According to
recent report, the present and future markets for non!cryogenic gas separations include the following:• Air )eparation !!nitrogen and oxygen enriched air
• atural 1as -lean up
• 6ydrocarbon -lean!up
• 6ydrogen )eparations
• 6ydrogen recovery from off!gases
• *iscellaneous !!rare gases, drying