INTRODUCTION
Cryogenics is defined as that branch of engineering which deals with the production of very low temperature and their effect on matter.A formulation which addresses
both aspects of attaining low temperatures which don’t naturally occur on earth and of using them for the study of nature or the human industry. Liquid nitrogen is the widely produced and most common cryogenic liquid.It is mass produced in air liquefaction plants . The liquefaction process is simple,atmospheric simple,atmospheric air is passed through through a filter and precooled using conventional refrigenation techniques . Then it is compressed inside large compressor and allowed to expand rapidly through expander into an insulated chamber. Liquid nitrogen is removed from the chamber by cryogenic fractional distillation column and is stored inside well insulated Dewar flasks. Heat from the atmosphere vaporizes liquid nitrogen under pressure and produces CNG.
1
OBJECTIVE To understand,
The production of liquid nitrogen from cryogenic nitrogen process.
To know the properties of liquid l iquid nitrogen.
To know the process description and what happens inside the every equipment.
Safety and environmental aspects which are required for the process. To calculate,
The Material and Energy balance.
The Size of the equipments.
Cost and economic feasibility of the process.
2
PHYSICAL PROPERTIES
Colorless.
Cryogenic fluid (temperature, −150 °C). Density
: 0.807 g/cc
Boiling point
: −196 °C (77 K; −321 °F)
Freezing point
: −210 °C (63 K; −346 °F)
Dielectric constant
: 1.43
3
PROCESS DESCRIPTION The free saturated air is sucked s ucked from the atmosphere through a highly efficient suction filter in to the first stage of the horizontally balanced opposed, lubricated reciprocating air compressor. Compressed air is chilled to 12 0C in a chilling unit, compressed air passes through the coils of chilling unit at a temperature of 120C to a moisture separator, where the condensed moisture gets removed before entering in to Molecular Sieve Battery. The chilled air passes through the molecular sieve battery consisting of twin tower molecular sieves packed with activated carbon, sil ica gel to remove carbon dioxide , argon and moisture Molecular sieve battery operates on twin tower system, when one tower is under production the other tower is regenerated by passing waste nitrogen gas. After interval of 8 to 10 hours the tower under production gets gets exhausted and regenerated by the similar process before uses and thus the cycle continues. AIR SEPARATION Chilled oil free and moisture free air enters into multi pass heat exchanger no1when it gets cooled to -80 deg C by cold gained from outgoing waste nitrogen and oxygen A part of air this enters a multi pass heat exchanger no2 or liquefier made of special alloy tubes. This air cools to (-170)deg C before passing through an expansion expansion valve, air further cooled down and gets gets liquefied before entering into bottom column. Rest of air at (-80)degC from heat exchanger no1 enters into t he highly efficient expansion engine, where the air further gets c ooled down to 4
(-150)degC before entering into the bottom column. The liquefied air from both these streams collected at the bottom column is known as Rich liquid
5
FLOWCHART
6
USES
Storage of living tissue.
Storage of sperms and other biological specimens.
Paint removal.
Cryogenic food storage.
Production of ice creams.
7
MATERIAL BALANCE
8
3
Basis :-1000 m /hr
Composition of air
N2
: 78.08%
O2
: 20.95%
Ar
:0.93%
CO2
: 0.038%
Rest
: 0.002%
(Xenon, Neon, Hydrogen, Helium, Krypton) Since the air contains most of nitrogen78.08%, liquid nitrogen can be liquefied from any air source are can get through gas producing factories since in here we are taking air as the basis we have to consider all the components present in the air oxygen, argon, corbondioxide and rest of the gases.
9
FILTER
Rest(0.2m3)
N2(780.0 m 3)
m
O2(207.5m3)
FILTER
Ar(9.3m3)
3
Air=1000m
Co2(3.2m3) Total =1000m 3
Total=1000 m 3
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COMPRESSOR
N2(780.0) O2(207.5)
COMPRESSOR 70 % Efficient
N2(546) O2(145.25)
Ar(9.3)
Ar(6.51)
CO2(3.2)
CO2(2.24)
Total=1000
Total=700
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CHILLER
N2(546) O2(145.25)
N2(546) CHILLER
O2(145.25 )
Ar(6.51)
Ar(6.51)
CO2(2.24)
CO2(2.24)
Total=700
Total=700
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MOLECULAR SIEVES
Ar(6.51) Undesired CO2(2.24) Undesired
N2(546) O2(145.25) Ar(6.51)
N2(546) Desired
MOLECULAR SIEVES
O2(145.25) Desired
CO2(2.24) Total=700
Total=691.25
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HEAR EXCHANGER 1 N2(546) O2(145.25)
N2(546) HEAT EXCHANGRE 1
O2(145.25)
Total=691.25
Total=691.25
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HEAT EXCHANGER 2
N2(546) O2(145.25)
N2(502.32)
HEAT EXCHANGER2
O2(145.25)
Total=691.25
Total=691.25
15
EXPANDER
N2(546)
N2(546)
EXPANDER
O2(145.25)
O2(145.25)
Total=691.25
Total=691.25
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CYOGENIC DISTILLATION COLUMN
GO2=20%(145.25)=29.05
N2(546)
CRYOGENIC DISTILLATION COLUMN 100% Eficeincy
O2(145.25)
LN2=80%(546) =436.8 GN2=546-436.8 =109.2
LN2=80%(145.25)=116.2
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OVERALL MATERIAL BALANCE INPUT=ACCUMALATION+OUTPUT 1000 m3=637.67 m3+3362.33 m3
18
ENERGY BALANCE
19
HEAT EXCANGER 1
N2 =12901.01 KJ
N2 = 12998.56 KJ
Q1=16399.68 KJ
2=16430 KJ
HEAT EXCHANGER 1
Q3=16411.68 Q O2 =16411.68KJ
Q4=16418.35 KJ Q3+Q2=Q1+Q4
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Q O2 =3492.5325 KJ
COMPRESSER
Q = 3298.212
COMPRESSER
Q=3954.876
21
HEAT EXCHANGER 2
Q2= 242338.80 KJ
HEAT EXCHANGER 2
Q3= 16418.35 KJ
Q1 =258757.15 KJ
22
CRYOGENIC DISTILLATION COLUMN
Qf= 4056.140 KJ
-1700C,8 bar
-1800C,4 bar
Qd=9091.06 KJ Qc=171693.94 KJ
Qa+Qb= Qc+Qd+Qe+Qf
-1700C, Qa=193871.114KJ
-1500C Qb=3954.876 KJ
-1800C,1.3 Qe=14848.92 KJ
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CALCULTIONS FOR ENERGY BALANCE QN2=(mC pT)
=ρ*V*C pT HEAT EXCHANGER 1 (at 12 0C) =(0.0803*542.56)*1.039*(12+273) =12901.01 Kj. Density calculations;
ρN2=(PM)/RT. =(6.8*28)/8.314*285. =0.0803 kg/m 3 QO2=0.0918*146.65*0.915*(12+273) =3510.67 Kj. QN2+QO2=16411.68 Kj. At (-800C) QN2=0.1186*546.56*1.039*(273-80) =12998.56 Kj QO2=0.1356*146.65*0.910*(273-80) =3492.5325 Kj QN2+QO2=16418.35 Kj. HEAT EXCHANGER 2 (At -170 0C) QN2=4.18*546*0.9007*(273-170) =220026.645 = 220026.645*0.8 220026.645*0.8
24
= 176021.316 Kj.
QO2=1.64*146.25*0.9007*(273-173) =22312.24 =22312.24*0.8 =17849.79 Kj.
QN2+QO2=242338.90 Kj. 80% of 242338.90=193871.114 242338.90=193871.114 Kj.
At (-1720C)
QN2=4.29*502.77*0.9007*(273-172) =20567.542 Kj
QO2=1.65*134.90*0.9006*(273-172) =20246 Kj QN2+QO2=242338.80 80% of 242338.80=193871.04 Kj.
EXPANDER (At -80 0C) QN2=0.1186*109.312*1.039*(273-80) =2599,712 Kj QO2=0.1356*29.33*0.910*(273-80) =698.50 Kj QN2+QO2=3298.212 Kj At(-1500C) QN2=0.0073*109.312*1.039*(273-150) =101.97 Kj QO2=1.2*29.33*0.8900*(273-150) =3852.906 Kj 25
QN2+QO2=3954.876 Kj
CRYOGENIC DISTILLATION COLUMN QLN2(At-1800C)=5.1*402.16*0.90*(273-180)
=171693.94 Kj……………………….1 QGN2(At-1700C)=4.19*100.55*0.21*(273-170)
=9091.6 Kj1…………………………2 LO2(At-1820C)=1.68*107.92*0.90(273-182)
=14848.92 Kj………………………….3 GO2(At-1700C)=1.64*26.98*0.89*(273-170)
=4056.140 Kj…………………………4 1+2+3+4=QN2+QO2(At-1700C) 199689.20 =199689.20
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DESIGN OF EQUIPMENT
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DESIGN OF SHELL AND TUBE HEAT EXCHANGER AVERAGE DENSITY OF NITROGEN AND OXYGEN AT 120C FORMULAE
ρavg =x1 ρ N2+x2 ρO2 =0.79*0.0803+0.021*0.0918 =0.0827 kg/m3 Similarly
AVERAGE DENSITY OF NITROGEN AND OXYGEN AT -800C
ρavg=0.122kg/m3 Cpavg of N2 and O2 at 120c formulae cpavg=x1 cp1 +x2 cp2 =0.79*1.039+.021*0.915 =1.0130 kj/kgk. Similarly Cpavg at -800 c =1.0130 kj/kgk
Average thermal conductivity at 120c Kavg=x1 k1 +x2 k2 =0.79*0.024+0.21*0.034 =0.0262 w/mk
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Similarly
Average thermal conductivity at -800c=0.028 w/mk
Average thermal conductivity at 120c
μ= μ0(a/b)(T/TO ) 3/2 (suntherland formulae). a=0.555*T0 +C b=0.555T+C CN2=111 T0 N2=541 R0=302.96K (1R0=0.56K)
μ0 N2=0.178cp CO2-1.27 TO02=526 R0=294.56K
μat 120C=0.017*10^-3 pas (FOR N2) μat -800C=0.704*10^-3 -800C=0.704*10^-3 pas (FOR N2) μ O2 AT 120C = 0.0170*10^-3 pas
μ O2 AT -800C =0.0122*10^-3 pas
μavg N2=x1 μ1+x2 μ2 =1.7*10^-5 pas
Q=U0 A ΔTlmtd 1/ UO=1/h0 +DO/Di*1/hi+D0/Dl (X/K) Nu=0.023*(Nre)^0.8*(pr)^.3 Nu=0.023*(Nre)^0.8*(pr)^.3
29
Nre=74581.18. Pr=5.065*10^-4 Nu=18.67 hi=39.70 w/m2k ho=9.43 w/m2k Dl=0.01792 m Uo=7.27 w/m2k AREA=236.3m2
The common common tube length’s for shell tube are 5,8,12,15,20 ft If we take length of the tube is15m the no tubes is 250. Optimum tube length to shell dia fall with in 5 t0 10m(colusnRichardson) Tube pitch =D0*1.25 =0.025m(applicable for triangle and square pitch colusn Richardson page no 592)
For 2passes K1=0.249 N1=2.207 Formulae Db=do(Nt/k1)1/n1 =0.02(636/0.249)1/2.207 =0.70m Since in the process gases involved we can take fixed head and find the value in the table (coulson Richardson page no 590) The value we get is 15mm thickness To find Shell diameter a=0.025m2 30
an=2*125*0.866*0.02=4.33m2
D=√an*4/3.14 Ds=2.5m
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COST ESTIMATION
32
COST ESTIMATION FORMULAE
I = IF+IS+IW IF=Fixed capital investment in process area IA=Capital Investment in auxillary services IW=Capital investment as working capital Equipment
unit
Cost Rs(LAKH)
Air filter
1
64.00,000
Air Compressor
1
38,00,000
Chiller
1
1,70,30,000
Molecular Sieves
1
1,60,000
Heat Exchanger
2
12,00,000
Turbine
1
5,00,000
1
3,50,000
Cryogenic Distillation Column
Liquid Storage Tank
16,80,000 total
3,12,00,000
The equipment cost is chosen according to plant size and area of the plant and nature of the metal using in each equipment operating pressure temperature.
DIRECT COST FACTOR 33
Items
Factor
1
Delivered cost of equipments Equipment installation
0.25
Installation
0.25
Instrumentation
0.25
Piping
0.60
Land and building
1.5
Foundation
0.20
Electrical
0.15
Clean up
1.5
Total
5.7
DIRECT COST OF PLANT= DIRECT COST OF MAJOR EQUIPMENT*TOTAL DCF/10 =(312*5.7)/10 =178 LAKHS
INDIRECT COST FACTOR (ICF) 1. OVERHEAD CONTRACTOR
0.21
2. ENGINEERING FACTOR
0.33
34
3. CONTIGENCY FACTOR
0.42
TOTAL ICF
0.96
INDUSTRIAL PLANT COST =DIRECT COST OF PLANT* TOTAL ICF =178*0.96 =172 LAKHS FIXED CAPITAL INVESTMENT(=IF)IN PROCESS AREA =DCP+IPC =178+172LAKHS =350LAKHS CAPITAL INSVESTMENT IN AUXILIARY SERVICES ITEMS COST FACTOR
AUXILIARY BUILDINGS
7.5
WATER SUPPLY
1
ELECTRIC SUBSTRCTION
0.75
PROCESS WASTE SYSTEM
0.5
MATERIAL STORAGE
0.5
FIRE PROTECTION SYSTEM
0.35
ROADS
0.25
SANITARY AND WASTE DISPOSAL DISPOSAL SYSTEM 0.1
COMMUNICATION AND FENCING TOTAL
0.2 11.15
CAPITAL INVESTMENT IN AUXILIARY SERVICES IA =FIXED CAPITAL INVESTMENT IN PROCESS*AS COST FACTOR/100 =350*11.15/100 = 39 LAKHS 35
INSTALLED COST =FIXED CAPITAL IN PROCESS+CAPITAL INVESTMENT IN AS =350+39 =389 LAKHS CAPITAL INVESTMENT AS WORKING CAPITAL,IW This is the capital invested in the t he form of cash to meet day to day expenses inventories of raw materials and products. the working capital may be considered as 15% of the total investment made in the plant Capital investment as working capital. IW = 69 lakhs
ESTIMATION OF MANUFACTURING COST DIVIDED IN TO THREE A. COST PROPOTIONAL TO TOTAL INVESTMENT B. COST PROPORTIONAL TO PRODUTION RATE C. COST PROPORTIONAL TO CARBON REQUIRMENT A Cost proportional to total investment this includes the factor which one independent of production rate and proportional to fix ed investment such as
Maintenance carbon and material
Property taxes
Insurance
Safety expenses
Security and first aid
36
For this purpose we shall change 15% of the installed cost of plant =installed cost*. 15 =389*.15 =59lakhs Cost proportional to production rate Factor proportional to production are
Raw material cost
Utilities cost – power,fuel,water,stream
Maintenance cost
Chemical,warehouse,shipping,expenses etc
Assuming cost proportional to production rate =total capital investment*.60 =458*.60 =275lakh Cost proportional to labor requirement This cost requirement amount to 10% of total manufacturing Cost =[(275+59)*1]/9 =37 lakhs Manufacturing cost =37+275+59 =371 lakhs Sale price of product Rs 80/l Income through sales = 800lakhs.
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PROFITABILITY ANALYSIS
A DEPRECIATION According to sinking fund method R=(V-Vs)I/(I+1)n -1 =(V-Vs)I /(1+I)n-1 R=uniform annual payment made at the end of each year V=installed cost of plant Vs=salvage value of plant after n year N=life period (assumed to be 15 years) I=annual interest rate (take 15%) R=(389-0)*.15/(1.15)15-1 = 8.17lakhs
GROSS PROFIT
GROSS PROFIT =TOTAL SALES INCOME-MANUFACTURING COST = 800-371 = 429 LAKHS NET PROFIT
Its defined as annual rate of return on investment made after deducing depreciation and taxes. The rate is assumed to be 40% NET PROFIT=GROSS PROFIT – DEPRICIATION DEPRICIATION – (GROSS (GROSS PROFIT *TAX RATE) =(429-8.17)-(429*.40) = 249 lakhs 38
ANNUALRATE OF RETURN
RATE OF RETURN =(100*NET = (100*NET PROFIT/INSTALLED COST) =100*249/389 =64% PAYOUT PERIOD
=DEPRICIATION FIXED INVESTMENT/PROFI INVESTMENT/PROFIT+DEPRITIATION T+DEPRITIATION =249/369+8.17 =8 YEARS.
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PLANT LAYOUT
40
Security building
o A f f d i m c e i n i s t r a t i o n
C a n t e e n
Power house
Time office Stores
Storage
Processing unit
41
Rest room
This is the common layout for any chemical industry where product must be stored in high pressurized tanks since this project is manufacturing of liquid nitrogen from cryogenic process the storage is very important for this kind of products.
42
THE PROCESS LAYOUT OF LIN PLANT
STORAGE AREA
43
Plant location and site selection
The location of the plant can have a crucial e ffect on the profitability of a project and a nd the scope for future expansion. Many factors must be considered when selecting a suitable site. The factors to be considered are; 1.
Location with respect to the marketing area.
2.
Raw material supply.
3.
Transport facilities
4.
Availability of labor.
5.
Availability of utilities: water, fuel, power.
6.
Availability of suitable land.
7.
Environmental impact, effluent disposal.
8.
Local community considerations.
9.
Climate.
10.
Political and strategic considerations.
Marketing Area: For materials that are produced in bulk quantities such as cement, mineral acids and fertilizers where the cost of the product per tonne is relatively relativel y low and the cost of 44
transport a significant fraction of the sales price, the plant should be located close to the primary market.
Materials: The availability and price of suitable raw materials will often determine the site location. Plant producing bulk chemicals are best located close to the source of the major raw materials; where this is also close to the marketing area.
Transport: The transport of materials and products to and from the plant will be overriding considerations in site selection. If practicable, site should be selected that is close to at least two major forms of transport: road, rail, waterway (canal or river) or a sea port.
Availability of labor: Labor will be needed for construction of the plant and its operations. Skilled construction workers will usually be brought in from outside the site area, but there should be an adequate pool of unskilled labour available locally.
45
Utilities (services) Chemical processes invariably require large quantities of water for cooling and general process use and plant must be located near a source of water of suitable quantity. Process water may be drawn from a river, from wells or purchased from a local authority.
Environment impact and disposal: All industrial processes produce waste products and full consideration must be given to the difficulties and cost of the disposal. The disposal of toxic and harmful effluents will be covered by local regulations and the appropriate authorities must be consulted during the initial site survey to determine the standards that must be met.
Local community considerations: The proposed suitable land must be given to the plant so that it does not impose a significant additional risk to the community.
Land (site selection) Sufficient suitable land must be available for the proposed plant and for further expansion. The land should ideally be flat, well drained and have suitable load bearing characteristics.
46
SAFTEY A little caution is needed when you handle liquid nitrogen the primary facts to be considered are
LN2 is extremely cold. At atmospheric pressure, liquid nitrogen boils at -196°C.
LN2 produces a large amount of gas . One liter of liquid nitrogen vaporizes into almost 0,7 m 3 of nitrogen gas. Either of these two properties can produce personal injury or property damage.
Do not allow objects cooled by liquid nitrogen to touch your bare skin. Contact with the skin may cause serious frostbite. Because it is extremely cold, it can freeze human flesh almost instantaneously. Even worse than sticking your tongue against the bottom of an ice-cube tra y fresh from the freezer, objects cooled by liquid nitrogen may stick to the skin and tear flesh away when you attem pt to remove the object. Use forceps or tongs to remove straws or canes fr om the storage container.
Protective clothing can reduce the hazards of handling liquid nitrogen. Insulated or heavy leather gloves should always be worn when handling any object that has been in contact with liquid nitrogen. Loose fitting gloves are recommended so that they may be discarded quickly in the event that any liquid nitrogen splashes into them. lf you are working with op en containers of liquid nitrogen, boots should be worn and trousers should not be tucked into the boots, but worn outside.
Special containers are required. Cryobiological storage containers are specifically designed and constructed to withstand the extreme temperature variances involved in handling liquid nitrogen. These special containers should be filled slowly to avoid the expansion stress that occurs as a r esult of the rapid cooling. T oo much stress can damage the container.
Do not seal the containers. 47
Cryobiological storage containers are designed to function with little or no internal pressure. The use of any tight-fitting stopper or plug that prevents the adequate venting of gas b uilds up pressure that could severely damage or even burst the container. Even icing or accumulated frost can interfere with proper venting and containers should be checked for such obstructions. To assure safe operations, only the original necktube core or approved accessories for closing the necktube should be used.
Transfer liquid nitrogen with care. The primary hazards of transferring liquid nitrogen from one container to another are spilling and splashing. Special funnels (with the top partially covered) will reduce splashing. For cr yobiological storage containers a self pressurizing discharge device is available that allows controlled LN, withdrawal up to two litres per minute. Always follow carefully the instructions on containers or accessories when transferring liquid nitrogen. Never overfill the containers. Filling above the specified level is likely to produce spillage when the neck tube core is replaced.
Use solid metal or wooden dipsticks. Because of the extremely low temperature of liquid nitrogen, plastic measuring devices tend to become very brittle or even shatter. Never use hollow rods or tubes; the gasification and expansion of the rapidly cooling liquid inside the tube will force liquid to sp urt from the top of the tube. Always wear insulated or heavy gloves when measuring.
Nitrogen gas is colourless, odourless, tasteless. It reduces the concentration of oxygen and can cause suffocation. Since it cannot be detected by sight, taste or smell, it may be inhaled as if it were air. That is why liquid nitrogen must always be stored and used only in areas that are fully ventilated. As liquid nitrogen evaporates, the resulting nitr ogen gas displaces the normal air-and breathing air that is less than 18% oxygen may cause dizziness, unconsciousness and even death.
To lessen the danger from nitrogen gas. liquid nitrogen should be disposed of ONLY in outdoor areas. T he liquid should be poured slowly onto the ground (never on pavement) where it can evaporate into the open air.
Store containers in clean, dry areas. Moisture, manure, caustic cleansers, chemicals or other substances which might cause corrosion should be removed at once. Wash containers containers with plain water or mild detergent solution and then then wipe dry.
Transport containers with care.
48
Closed trucks or vans are not recommended for transporting cryobiological storage containers; ventilation is required to prevent nitrogen gas from accumulating. In addition, containers should be secured in an upright position to prevent spillage and they should be protected from heavy jolting or colliding with one another.
Handle containers with care. A few simple precautions in the handling of your cryobiological storage containers can protect you and your valuable stocks . Containers should always be stored in an upright position. Tipping the container or letting it lie on its side can result in spillage and may damage the container or the materials stored in it. Dropp ing the container or subjecting it to severe vibrations may damage the vacuum insulation system. Walking or dragging containers could result in a partial or complete vacuum loss. For containers that cannot be easily and safely carried, a roller base can provide safe and easy movement of containers.
Container Contents. The extremely low temperature of the liquid nitrogen or nitrogen gas provides the protection of the materials stored in cryobiological storage containers. When all of the liquid nitrogen has evaporated, the temperature inside the container will rise slowly. The rate of evaporation depends upon the age, condition and use pattern of the container. Opening and closing the container or moving it about will reduce its cooling efficiency. You should check the liquid nitrogen level in your containers at least weekly; make sure there is enough liquid nitrogen in the container to maintain the required temperature to avoid damage to the ampoules, canes, straws or vials stored in the container. lf the liquid has evaporated faster than usual or if the container is covered with frost or condensation, the vacuum system may be damaged. In such instances, transfer the contents to another contai ner and remove the damaged one from service at once.
FIRST AID If anyone working with liquid nitrogen becomes dizzy or loses consciousness, move him to a fully ventilated area at once and call a doctor. If he appears to have difficulty breathing, administer oxygen. Where breathing has stopped, apply artificial respiration immediately and then give o xygen. Keep the person warm and as calm as possible until the doctor arrives. If a person is exposed to liquid nitrogen or gas, t he affected tissue should be r estored to normal body temperature as quickly as possible. Remove or loosen any clothing, belts, collars, etc., that might restrict circulation to the affected area, and bathe or immerse the area in water heated to 42°C. Do not heat water above 45°C. Protect the injured tissue from further damage or infection and call a doctor. Do not rub the affected area in an attempt to improve circulation
49
6Personal protection equipment Special instructions for protection and hygiene
Wash the hands before breaks and after work. DURING TANK CLEANING OPERATIONS FOLLOW SPECIAL INSTRUCTIONS (risk of oxygen displacement and ethers). Respiratory protection
Respirator (organic vapor filter, type Ax) Hand protection
Protective gloves (e.g. of butyl rubber). Eye protection
Safety goggles if there is a risk of splashing. s plashing. Skin protection
Protective clothing when needed.
STORAGE
50
CONCLUSION LIN is prodeuced this process was selected as it was simple in concept, economical and has the virtue of being a single product technology, an important consideration for product of such enormous volume. volume. In this project we had dealt with the cost estimation and the feasibility of the project.
51
BIBILIOGRAPHY
Encyclopedia of chemical engineering Krick othmer
Cryogenic systems by Randall F.Barron
Compressors by Royce N. brown
Chemical engineering by Coulson and Richardson
Perry’s hand book of chemical engineering
Cryogenic engineering by Thomas Thomas M Flynn
www.elsevier.com
www.bookaid.org
www.google.com
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