Modification of Design of Cryo-Oxygen Plant for Improved

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Modification of Design of Cryo-Oxygen Plant for Improved Performance Rama Rao T1* and Ranjan Ojha P2 1Professor Mechanical Engineering Deptt, Bhilai Institute of Technology Raipur, CG, India, 496331 2UG Scholar 8th Sem. Mechanical Engineering Deptt, Bhilai Institute of Technology Raipur, CG, India, 496331

Received: April 10, 2018; Accepted: April 26, 2018; Published: May 07, 2018

*Corresponding author: Rama Rao T, Professor Mechanical Engineering Deptt, Bhilai Institute of Technology Raipur, CG, India, 496331, Tel: +917898351444; E-mail: [email protected]

Abstract Studies in high energy physics: Development of an industry is very important for the nation oxidizer during combustion. detection and study of high energy particles. and so is its economical functioning. Cryogenics, being versatile in • Liquid hydrogen is used in its application needs proper nourishment and care, which is done Nuclear engineering applications: Preparation of Heavy ice, maintaining cryogenic temperatures for neutron is a very important item for high level research and applications. • Theby periodic possibility improvements of launching in space its systems. vehicle Specificallyhas also come liquid due Oxygen to the bombardment, etc. Electronics: item for doctors and many more. The necessity for the economic development of liquid oxygen. This also finds its use as a lifesaving maintaining suitable operating temperature. • Controlling voltage fluctuation, noise and There are many researches which has been done starting from Gyroscopes: development of these plants will benefit mankind in many fields. where support friction, wind age friction, problem of bearing • Superconducting gyro works in a high vacuum, reducing the cost of Oxygen Liquefaction and ultimately its production instability, and dimensional instability as due to superconductivity 90%for cryogenics. and the remainingThe only expenditure 10% is used for productionin running ofother liquid machinery Oxygen is andelectricity. lighting Out of of the the plants. total electricity Studies have consumed, also led compressor to the fact consumes that the and hence practically all these problems are eliminated. temperature also plays a great role in consumption of electricity. So in the thermal expansion coefficient of materials approaches zero Biology and medicine: Used in cryobiology and cryosurgery, this paper, an attempt has been done to reduce this temperature also. We have incorporated a solar refrigeration system and Freon cooler. • as a killing agent in food preservation, preservation of biological Booster compressor is also introduced and modification in it has led innermaterials ear surgery. likes blood, tissue and bone marrow. Also freezing to theKeywords: work saving up to 4.30%. techniques have been used in the treatment of eye surgery and Freon cooler; Booster Compressor; Space simulation: Creation of simulation chamber for Cryogenics; Liquefaction; Solar Refrigeration System; testing components for mission. Introduction • Manufacturing process: Used in steel manufacturing The subject of Cryogenics is very broad in scope and hence it is power• plant. means, literally, the production of icy cold. It is also used as a process, open hearth furnace, CO formation and space vehicle synonymnecessary tofor limit low the temperature, field to be considered. which involves The term temperatures cryogenics below -150 °C. The boiling points of so called permanent gases, There are significant effects on certain properties of materials whichMechanical is of great importance, properties: like: Yield stress, Ultimate stress and below -150°C, while the froe refrigerants, hydrogen sulphide, and Hardness for alloys and some other materials would increase such as helium, hydrogen, neon, nitrogen, oxygen and air, lie other common refrigerants all boil at temperature above -150°C. with• the decrease in temperature. Thermal Properties: Thermal conductivity of alloys and theCryogenics practical engineering utilization is ofthe low field temperature of developing phenomena. and improving [5] low temperature technique, process and equipment. It includes • impure metals, specific heats of liquids and solids and coefficient engineering and its productions are increasing yearly. Some areas Electrical properties: The cryogenics has a diversified application in the vital field of of thermal expansion decreases with the decrease in temperature. involving cryogenic engineering are: simultaneous disappearance of all electrical resistance and • At very low temperatures, Rocket propulsion system:

• Liquid oxygen is used as appearance of perfect diamagnetism takes place. In the absence

of magnetic field, many elements, alloy and compounds become or 99.76%, 0.04% and 0.20% respectively. The manufacture of super conducting at a fairly well defined temperature called liquid oxygen in large quantities is done by distillation of liquid transition temperature in zero field. air, since the oxygen is the second most abundant substance in air (20.95%Principle by of volume Air Separation and 23.20% by weight) (Table 1) [1]. is causedSpecifically either focusing by the onpresence the field of of the research, polymer end or product long chain here moleculeis Oxygen. orThe by liquid the oxygenunpaired has electrons characteristic which blue are colour, responsible which The basic principle of an air separation plant is liquefaction of air and separation of its constituents by rectification. As the for Para magnetism in liquid oxygen. At 1 atm pressure, liquid liquefaction of air is concerned to Cryogenic engineering, and oxygen boils at 90.2 K and freezes at 54.4 K. Saturated liquid there has been a great amount of work devoted to improve oxygen at 1 atm is dense than water at 60 °F. Liquid oxygen is are non-magnetic. Hence by measuring magnetic susceptibility, the efficiency of air separation plant. As the major source for slightly magnetic in contrast to the other cryogenic fluids, which gases) is air and commercial importance of these industrial manufacture of industrial gases (Oxygen, nitrogen and rare small amount of oxygen may be detected in mixture of other gases are known to us. The demand of Oxygen is comparatively gases. Liquid oxygen is chemically reactive, especially with safety problem in handling. more than other industrial gases. Attempts are to develop hydrocarbons. Because of its chemical activity, oxygen presents a Oxygen economically with desirable purity, i.e. with lesser power has only three stable isotopes of mass numbers 16, 17 and 18. consuming and equipment of high precision. As the raw material, Looking to the available isotopes we can conclude that Oxygen reducecost of producingelectrical Oxygenusage. Focusingis nil and onlyon the requirement air components, is electrical for energy. [2] Hence by using proper Cryogenic techniques we can TheTable relative 1: abundance of these three isotopes is 10000:4:20

Isotopes of Oxygen

Citation: Page 2 of 11 Eng 6(1): 1-11. Rama Rao T, Ranjan Ojha P (2018) Modification of Design of Cryo-Oxygen Plant for Improved Performance. SOJ Mater Sci Modification of Design of Cryo-Oxygen Plant for Improved Performance Copyright: © 2018 Rama Rao T, et al.

simplicity air will be considered to be a binary mixture of 21% of 2 and water vapour, but Oxygen and 79% of Nitrogen, moreover the air introduced to the isseparation complicated process and cannotis kept befree ignored, from CO but for understanding the fundamentalsit does contain of 0.93% air separation of Argon. we It’s ignore true this that added presence complication. of Argon

Other gases like Helium, Neon, Krypton and Xenon are present complicationsin small quantities (Table and 2) have[6,12]. boiling points so far removed from those of Oxygen and Nitrogen that they introduce no important Table 2:

TypicalImpurity impurities in Air (ppm)Normal Maximum Water - Saturated 1000 Figure 1: log C ) ------(i) Carbon dioxide 3500.1 1 Air liquefactioni i Process Ethylene 0.01 200 Acetylene WRWhere = R C Ti ∑ (C Propylene - 0.2 = Molar concentration of ith component Methane 2.5 10 The ideal work is known as minimum work of separation. To Butane - 0.1 find out work of separation per kg Mole of a particular product, - 0.05 isWR carried is divided out at by low molar temperature. concentration However of thesince product the feed in and the SulphurCarbon mono-oxidecompounds - 0.1 original mixture. In cryogenic process, the actual separation The simplest form of air separation plant was the originals adiabaticproduct gases control are volume all at ambientwhich surrounds temperature, (Figure the 2), steady the plant flow atenergy ambient equation temperature may be and applied observing to whole that net plant rate byof supply using anof single column lined cycle plant which was first operated in 1902; heat per unit mass through the feed and product stream is given hereSize: is a brief classification according to the following basis: by: • Small plants (producing less than 750 cu.M/hr) and TonnageOperating plants Pressure: (producing more than 750 cu.M/hr) Q = T CiSi – T So bar)• High pressure plant (more than 35 bar), Medium pressure plant (6-35 bar) and Low pressure plant (5-6 Where Si = entropy of the ith component Process cycled: And So = entropy of feed • Cryogenic plants and Non-cryogenic plants or These results are identical to equation (i), as it shows the total Type of expansion: PSA plants work required for separating a particular component depend to • Free expansion or J-T expansion type plants some extent on how many other gases are produce. For example andRectification Expansion enginecolumn: type Single plants column and Double column plants if it is considered to contain 21% Oxygen, the work required to separate Oxygen only, leaving the other gases mixed is 5555 • In air separation plant, cooling it until its condensation temperature is reached and then removing the latent heat of kJ/Kg mole, while if Oxygen (21%) and Argon (0.934%) are separated, the work to separate Oxygen increases to 6104 kJ/kg mole Oxygen and the work of separation for Argon being 137,000 vaporization accomplish the liquefaction of air. Thus a suitable highkJ/kg cost mole. of theThis rare also gases. illustrates the marked dependence of the refrigeration process creates perfect air liquefaction (Figure 1), work on initial concentration, which at least partly explains the of gases is an important aspect of cryogenic engineering and is Cryogenic Air Separation process usuallywhich varies achieved to the by practical fractional methods. distillation. The separationIndustrially, of themixture two most important processes are separation of component of air and The Cryogenic air separation process may be considered as a series of unit operations. The various components are closely integrated by the process designer and optimized to suit the the modification of the composition of natural gas. To illustrate the principle let us take separation of air, which particular product requirements and to suit the energy source will be treatment as mixture of 21% of Oxygen and 79% of bars and sometimes higher. There are some important factors and cost of compressor operation. It generally works at 6-6.5 Nitrogen only. The ideal work WR per mole required to separate a mixture of perfect gases into its components at a temperature T energy consumption, investment cost, product purity, product for a perfect gas, the internal energy is a function of temperature influencing the selections of the process like product quantity, only.may be calculated from the entropy of mixing, remembering that state, continuity of product supply, plant flexibility, maintenance Citation: Page of 11 Eng 6(1): 1-11. Rama Rao T, Ranjan Ojha P (2018) Modification of Design of Cryo-Oxygen Plant for Improved Performance. SOJ Mater Sci 3 Modification of Design of Cryo-Oxygen Plant for Improved Performance Copyright: © 2018 Rama Rao T, et al.

Figure 2: Process Flow Diagram cost, and permissible plant dimensions. Removal of impurity =2494.2 X 0.5095076 from feed air is important task [3,7,11]. =1270.8 kJ/Kg Water and CO2 must be removed from air feed to prevent Therefore the work required for separation of unit of mass of blockage of process equipment. Here regenerators and reversing Oxygen gas from air will be 1270.8 kJ/Kg. heat exchangers operate during the cooling of air flow while eitheradsorption molecular occurs sieve before + activated the main heatalumina exchanger. drier of For reversing purification heat whichA seriesis the cascading of operations of several similar evaporations to the ideal and Linde condensations, Hampson of air, removal of moisture and carbon dioxide after compression System is carried out. Separation of gases is done by Rectification, exchanger or pressure swing adsorption system are adopted. The carried out in counter flow. Including the operations guided use of reversing heat exchangers has been gainfully adopted on by Linde double column system, processes are kept to the The visualization of a thermodynamically ideal and reversing plants of 1600 cum/hr capacity and above [9]. followingapproximation processes: of Isothermal compression. This is impossible to system for the separation of gases can be provided some insight achieve it in practice but approximately it is kept near to it by systems. In such system, gases are reversibly separated using cylinder. factiousinto operation semi permeable and energy membranes. requirements of various practical • Cooling the air during compression by spraying cold water into

• Cooling the air during compression by circulating cold water Work involved in reversibly separating specified gaseous through the cylinder jacket. component of air at 300 K. The ideal work requirement in kJ/kg of • Adopting multi-stage compression with inter stage cooling. Oxygen to reversibly isothermally separate, from air. Air mixture process. It is a common practice to provide intercoolers between is considered to be consisting of 79.054% Nitrogen, 20.946% the Thiscylinders keeps of the multistage compression compressors, process nearfor the to purpose isothermal of Oxygen, by volume at 300 K [8]. cooling the compressed air to atmospheric temperature before entering the succeeding stage. Using(-Wm equation,m) Tm E Yi i) /N ln (1/Y Equipments To separate Oxygen Component from air the work of Air Compressor: separation(-Wm requiredm can be calculated as follows: • I.R. compressor having four stages of /N ) =8.314 X 300 X [0.79540 ln (1/0.79540) + 0.20946 compression is used. The power requirement to run the ln (1/0.20946)] compressor when fourth stage is delivering 876.4 PSIG is approx. 95 kWh. Clean, soft ware is used. Maximum water entering the =2494.2 X [0.1820751 + 0.3274325] [10,26]. system will be required for satisfactory performance (Table 3) Citation: Page of 11 Eng 6(1): 1-11. Rama Rao T, Ranjan Ojha P (2018) Modification of Design of Cryo-Oxygen Plant for Improved Performance. SOJ Mater Sci 4 Modification of Design of Cryo-Oxygen Plant for Improved Performance Copyright: © 2018 Rama Rao T, et al.

Table 3:

Stage The Suctionapproximate Temperature Air temperature °C atDelivery Suction/Discharge Temperature stages °C Type of absorbent – Molecular sieve type 13-X 1 157 Quantity of Molecular Sieve – 105 kg per each drier 2 35.0 170 Flow rate of regenerated gas – 440 cm.m/hr for 10 hrs 43.3 Regeneration electric heater: U shaped iron clad resistance. 108 Regeneration gas – Dry Nitrogen 3 43.3 163 This resistance is solder-raced on the tubular plate in order to Technical4 characteristics43.3 of air compressor: secure• tightness. There is a thermostat mounted on the inlet air

the outlet temperature reaches to 180 °C the molecular sieve is so as to prevent overheating. The electric heater uses 9 kW. When Air flow at average conditions = 444 Cu.M/h. regenerated. Suction temperature = 35 °C Ceramic filter: Suction pressure = 760 mm of Hg • The dry air is again filtered in a ceramic filter to avoidHeat any Exchanger dust entry - 1to: Thecold compressed box. air is cooled to about 20 AirRelative Compressor: humidity = 75% • • With pulley and belt guard °C and enters the heat exchanger-1 which is a multi-pass coil type heatHeat exchanger. Exchanger The - 2:incoming air is cooled to -100 °C.

H.P = 128.5 BHP (94.3 kW) • The air from heat exchange-1 is bifurcated into two streams. One stream is passed through heat exchanger-2 Volts = 440 at 40 kg/sq.m/-100 °C and further cooled to -155 °C by the AirAmpere Suction = 195 Filter: max. Dry type: Woolen pad inserted between outgoingExpansion Oxygen Engine: and Nitrogen. mesh. • • Main stream of air from H.E. 1 is expanded Evaporative Cooler: in an Expansion Engine to -15 °C. is an elliptical vessel split into two compartments. In each compartment• there is aAir pipe, is cooled coil and to aboutis interconnected. 20°C. This cooler The Type of Expansion Engine - SEM 0.5/1 No. of Cylinder = 1 coils are half submerged in water in the vessel. Dry Nitrogen will Inlet pressure = 60 kg/sq.C.M. be bubbled through this water to become wet gas. As the water itself. So water gets cooled. Thus inside the pipe coil will get Outlet pressure = 5 kg/sq.C.M. cooled.vaporizes, it requires latent heat and this is absorbed from water hr Throughout volume at 60 kgf/sq C.M. and 8 °C = 300N Cu. m/ Moisture Separator: Moisture is separated from compressed air cooled in evaporation cooler. Centrifugal type separator mode of• carbon steel. Throughout volume at 50 kgf/sq C.M. and -75 °C = 120-390 N.Cu m/hr Power required = 6.5 kW Overall dimensions are: ExpansionR.P.M = 200 Valve: rpm Height = 460 mm • The air will then expanded by an Expansion Diameter = 165 mm valveDistillation to form liquid Column: air.

Thickness = 22.5 mm coiled• vapor is at the bottom It is a ofdouble M.P. column, rectification which column acts as made a re- of three elements. A middle pressure column with 22 trap and WeightCondensed = 36 water kg is removed in every hour. boiler for the column. Oil Separator: Its function is to stop the traces of oil coming Insulating Jacket: It is made of metal which is closed by from compressor. The oil separator is made of domine forged removable panels and contains all elements, which are to • • compression unit of pump etc. The insulating material used is The dryer battery comprises of two bottleMolecular filled with sieve activated battery: carbon. mineralbe insulated wool and distillation perlite. column, coiled exchanger, cooler, process• air passes through the molecular sieve will absorb water • Lox pump: domine forged bottle filled with molecular sieve type 13-X. As the coming out from the fraction column. It is of reciprocating type 2 of the bottle and it goes out through the top. The adsorption cycle This pump is used to compress the liquid oxygen isvapour 10 hrs. and CO from air. The air enters at the bottom in the axis with its axis vertical, fixed on the rate frame of the insulating jacket with a flange.

Citation: Page 5 of 11 Eng 6(1): 1-11. Rama Rao T, Ranjan Ojha P (2018) Modification of Design of Cryo-Oxygen Plant for Improved Performance. SOJ Mater Sci Modification of Design of Cryo-Oxygen Plant for Improved Performance Copyright: © 2018 Rama Rao T, et al.

Calculation for selection of Booster Compressor for Oxygen Plant Type of pump = IL/IK/100/22 • No. of Cylinders = 1 Data Available Power required = 1.5 kW Free air delivery (FAD)m [1] = 440 N Cu. m/hr Normal delivery = 80 N Cu.m/hr Extraction = KYk/MY Discharge pressure = 165 kg/sq. C.M. Where: K – Flow rate of product 75 Cu. m/hr ModificationsSuction pressure = 0.5 kg/sq. C.M. Y Since the conventional plant consumes more power and M – Flow rate of frf in Cu. m/hr k Ym- Molar fraction of Oxygen in product = 0.995 efficiency is also low, we need to adopt certain modifications in – Molar fraction of Oxygen in feed = 0.21 theBoosting plant, like: up of[13,14,15] Oxygen plant: feed suitable air compressor can be added into the plant process For present Oxygen plant the maximum capacity of ADU and • By knowing exact quantity of Air ASU was mentioned to be 890 Cu. m/hr For double column air separator producing Oxygen as a circuit (Figure 3). product extraction factor is about 0.96-0.97

Figure 3: Plant Circuit

Table 4:

Taking the value of extraction factor = 0.96 for our use DescriptionList of EquipmentQuantity Rates Capacity/ Total Capacity kW kW With K = 75 Cu. m/hr 1 MY = 440 Cu. m/hr AirDrier Compressor heater 1 128.5/94.3- 94.39 k Ym = 0.995 1 - 7.5 Engine = 0.21 Expansion 1 - 2.2 Extraction factor = 0.9 (which is less than specific heat) gas blower 1 - 2.2 2Lox Pump For Extractionm factor to be 0.96 K will be DefrostN heater 1 - 2.2 0.96 =KYk/MY Cooling water 1 - pump 2.2 X 2 K = 89.14 Cu. m/hr Chilling plant 2 - 6 factor. Plant is getting fewer yields because of the poor extraction 1 - 1

Light loads Loss = 89.14 – 75 = 14.14 Cu. m/hr To get additional production of 14.14 Cu. m/hr for the same Through put: 120 N Cu. m/hr extraction factor 0.9 the additional Pressure: 40 Kg/sq. CM M = (14.14 X 0.995) / (0.9 X 0.21) Speed: 300 rpm = 74.4 N Cu. m/hr No. of cylinders: 2 serveSo the we purpose.need to increase the fee of air by an amount of 74.440 No. of stages: 3 Cu. m/hr. hence compressor of capacity (Table 4) 80 Cu. m/hr will Hence the following compressor is used: Theoretical Power = n/n – 1 P1V1 [1-(P2/P1) n/n-1] Where P1 = 1 Kg/sq. m T1 = 250 °C Citation:Name: SIEMENS Page 6 of 11 Eng 6(1): 1-11. Rama Rao T, Ranjan Ojha P (2018) Modification of Design of Cryo-Oxygen Plant for Improved Performance. SOJ Mater Sci Modification of Design of Cryo-Oxygen Plant for Improved Performance Copyright: © 2018 Rama Rao T, et al.

Table 5: Showing the saving resulting from moving the compressor P2 = 40 Kg/ sq. m airTemperature intake to cooler Intake one in Cu. m required % kW saving or V1 = 120 N Cu. m/hr of Air Intake to deliver 1000 Cu. m of increase relative to free air at 21 °C 21 °C n = 1.32 (assumed) -1 925 7.5 saving Putting all values, Theoretical Power = 20.5 kW. 5 5.7 saving

The maximum production rate observed by using this booster 10 943962 compressor is 86 Cu. m/hr, while it was expected to be about 90 16 981 3.81.9 saving Cu. m/hr. This reduced production rate is due to lesser FAD to the ASUReduction of the plant of (Figure head pressure: 4) [16-20]. High-pressure compressor is 21 1000 0 • 27 1020 1.98 saving Hencemore powerfulcold production per cubic by Freon meter system, of Oxygen where produced,Freon compressor as it is difficult to achieve isothermal efficiency and high Air losses. 32 10401060 3.85.7 saving which reduces head pressure, should be used. This also controls theis used inlet for temperature cooling air of by air providing to molecular Freon sieve exchanger batteries in tocold reduce box, 37 1080 7.6 saving moisture load in air driver unit. So Freon compressor along with 43 1100 9.5 saving Vaporization cooling system is adapted (Table 5). 49

Figure 4:

Modified Plant Circuit

Figure 5: 2)

Temperature Recorded in Modified Circuit Line. (Pressure = 49 kgf/cm Citation: Page 7 of 11 Eng 6(1): 1-11. Rama Rao T, Ranjan Ojha P (2018) Modification of Design of Cryo-Oxygen Plant for Improved Performance. SOJ Mater Sci Modification of Design of Cryo-Oxygen Plant for Improved Performance Copyright: © 2018 Rama Rao T, et al.

New Air purification System:

2 removal. The air inlet temperature is • Activated Alumina Drier is QWhere, = (A) XQ (U)- The X (Tp)rate of heat transferred (Watts) heatingused for temperature moisture and of COdrier cycle which will cause reduced drier cyclereduced timing from and 12°C, thus which power shows consumption lesser moisture by nitrogen in A.D.V. blower The ATp - - The The outside temperature surface difference is of Wall across (sq.m) the wall

Utilization of Cold: and regenerator purification heater (Figure 5). material used in the wall construction. Proper Insulating material U Factor depends upon thickness and thermal conductivity of • The quantity of heat transmitted through walls of refrigerator per unit of time is function of 3 factors whose to prevent heat intake into cooling system relationship is expressed in following equation: Table 6: Compressor temperature details Stage Pressure Ratio Suction Temperature °C Delivery Temperature °C Compression Index 1 157.22 1.7

2 2.245 35 170 4.209 43.3 160.25 1.309 3 3.26 43.3 108 1.36 Cooling4 tower modification:1.934 here use of Induced draft43.3 type Stage 2: 1.38 of cooling tower is used to save water, and ultimately energy for P plant.• 2 1 T Cooing of intake air: Solar operated adsorption refrigeration 2/P = 4.209 system is used to cool the suction air by providing Heat T1 = 170 + 273 = 443 K • = 43.3 + 273 = 316.3 K exchangers.Pre cooling of cooling water: From equation (*), • Water provided at 30-33°C is 4.209 = (443 / 316.3) (n/n-1) cooledPerformance further, so thatAnalysis compression & Results work is decreased [20,21,22]. •Compressor log 4.209 = (n/n-1) log [1.405] n = 1.309

StageP2 1 3: processCompression of each stage index: to With isothermal the help process, of compression where it indexis unity of T each stage one can know the closeness of actual compression /P2 = 3.26

T1 = 160.55 + 273 = 433.55 K (Table 6) [4,20,22]. = 43.3 + 273 = 316.3 K (P2/P1)Where, = (T2/T1) n/(n-1) ------(*) From equation (*), P2 3.26 = (433.55 / 316.3) (n/n-1) P1= Delivery pressure of each stage log 3.26 = (n/n-1) log [1.370] T2= Suction pressure of each stage n = 1.36 T1= Delivery temperature of each stage StageP2 1 4: Stage= Suction 1: temperature of each stage T2/P = 1.934 P2 1 T1 = 108 + 273 = 381 K T2/P = 2.245 = 43.3 + 273 = 316.3 K T1 = 157.22 + 273 = 430.22 K From equation (*), = 35 + 273 = 308 K 3.26 = (381.54 / 316.3) (n/n-1) From equation (*), log 3.26 = (n/n-1) log [1.206] 2.245 = (430.22 / 308)(n/n-1) Workn = 1.3 Done analysis log 2.245 = (n/n-1) log [1.396] n1− n P n 2 )1− • n1− n = 1.7020 P1 W = mRT [( ] ------(**) Citation: Page 8 of 11 Eng 6(1): 1-11. Rama Rao T, Ranjan Ojha P (2018) Modification of Design of Cryo-Oxygen Plant for Improved Performance. SOJ Mater Sci Modification of Design of Cryo-Oxygen Plant for Improved Performance Copyright: © 2018 Rama Rao T, et al.

Table 7:

M = 1 kg Stage DeliveryPressure temperature Suction for same pressureDelivery ratio (N=1.3) Temperature ratio Temperature °C °C N = 1.722 1 2.778 116 RStage = 0.287 1: kJ/kg °C 2 2.778 35 127 2.778 43.3 127 1.7 0.7 2.2451.7 )− 1 2.778 127 From0.7 equation (**) 3 43.3 1.3 0.3 W4 43.3 1.3 − W = X 1 X 0.28 X 308 [( ] 0.3 3.26 ) 1 3 WStage = 83.7186 2: kJ/kg W = X 1 X 0.287 X 316.3 [( ] 3 T1 = 118.142 kJ/kg 1.3 0.3 P W 1.9241.3 )− 1 2 = 2.731 + 43.3 = 316.3 Stage 0.34: 4 / P = 4.208 W = X 1 X 0.287 X 316.3 [( ] Total4 W N = 1.311 = 61.954in kJ/kg 1.3 0.3 1.3 From0.3 equation (**) 4.209 )− 1 = 405.615 kJ/kg W = X 1 X 0.287 X 316.3 [( ] % Saving in Win = [(427.513 – 405.615) / 427.513] X 100 W = 153.846 kJ/kg • Pressure ratio Analysis = 5.12 %

StageT1 3: different, but for better performance, pressure ratio in all the = 316.3 K (P2 / P1) = 3.26 As pressure ratio in all the four stages of compressor are N = 1.356 P1 1.36 0.36 stages should be equal (Table 7), 1.36 From0.36 equation (**) 1.934 )− 1 P2 = 1 atm W = X 1 X 0.287 X 316.3 [( ] Pressure = 60 atm ratio of each stage W = 124.467 kJ/kg

StageT1 4: (60/1)1/4 = 2.778 P2 = 316.31 HenceStage 1: comparing with the above value, all to be equal / P = 1.934 P2 1 N = 1.356 / P = 2.778 1.38 0.38 From equation (**) 1.9341.38 )− 1 0.38 R = 0.287 kJ/kg K W = X 1 X 0.287 X 316.3 [( ] NP1 = 1.3 1.3 W = 65.481 kJ/kg W 2.7780.23 )− 1 1= 3080.3 Total work input = 427.513 kJ/kg = X 1 X 0.287 X 308 [( ] 1.3 It is difficult to bring the temperature of compressor down to 0.23 compared for analysis of reciprocating compressor. W 2 =99.83 kJ/kg 2.778 )− 1 35 °C. In relation to this condition, the actual work input can be 0.3 Stage 1: = W3 = W4 = X 1 X 0.287 X 136 [( ] n1− n n P2 )1− Total Win − =103.12 kJ/kg n1 P1 W = mRT [( ] = 409.189 kJ/kg

NW =1 1.3 • Calculation% saving in for work Number = 4.29% of stages T Stage = 77.316 2: kJ/kg °C 2 1.3 0.3 W 1.3 T 2 0.3 4.209 )− 1 1 = 127 + 273 = 400 K P W2 = X 1 X 0.287 X 316.3 [( ] 2 = 351 + 2732 = 1308 K P = 148.203 kJ/kg 2 / P = (T / T )1.3/0.3 Stage 3: = 3.103 atm Citation: Page 9 of 11 Eng 6(1): 1-11. Rama Rao T, Ranjan Ojha P (2018) Modification of Design of Cryo-Oxygen Plant for Improved Performance. SOJ Mater Sci Modification of Design of Cryo-Oxygen Plant for Improved Performance Copyright: © 2018 Rama Rao T, et al.

Pressure at delivery industries economically. Hence this is a hypothetical calculation P d in the form of values obtained after detailed mathematical done based upon studies on the oxygen plant design. The findings (P d= 60 atm d 2

/ P2) = (T / T ) N (1.3/0.3) iscalculation advised to is be verified used in by cryogenic adopting plants it in cryogenicglobally. liquid oxygen plant and this has led to the saving of work up to 4.30%. Hence it (60/ 3.103) = (1.278) N (1.3/0.3) References N = 2.7 1. (T ) So the total no. of stages required are =p N +2 1 =1 3.7 or 4 Allam RJ. Improved Oxygen Production Technologies. Energy Procedia. 2. Heat removed from intercoolers = m C – T 2009;1(1):461-470. Prakash Rao, Michael Muller. Industrial Oxygen: Its Generation and Total heat rejected = Intercoolers-(1+2+3+4) Use. Center for Advanced Energy Systems, Rutgers, the State University = (112.896+128.016+118+45.36) kJ/kg of New Jersey. 2007. Heat rejected during = 404.3Compression kJ/kg process 3. Lebrun PH. President, Commission A1 “Cryophysics & Cryoengineering” of IIR Accelerator Technology Department, CERN, Geneva, Switzerland. Departmental Report. An Introduction to Cryogenics. CERN/AT 2007-1. nC V= 1.3 4. Indian Cryogenics Council; Proceeding (Part-A) of Twenty Third = 0.72 kJ / kg National Symposium on Cryogenics (NSC-23); Indian Journal of 5. Cryogenics. 2011;36(1-4):ISSN:0379-0479. yT 1= 1.4 Mohite NY, Kale BN, Patil VV. Cryogenics- Birth of an Era. International T 2 = 35 + 273 = 308 K 6. Journal of Computer Applications, NCIPET. 2012;9:24-26. Stage = 157 1: + 273 = 430 K Khalel ZAM, Rabah AA, Barakat TAM. A New Cryogenic Air Separation yn− H ( ) (T ) Process with Flash Separator. Hindawi Publishing Corporation; ISRN 1 v n1− 2 1 7. Thermodynamics. 2013;1-4. 1.4− 1.3 = C 1.3− 1 – T Chhaniyara A. Cryogenic Rocket Engine. International Journal of 8. Mechanical Engineering and Robotics Research. 2013;2(4):373-378. = 0.72 ( ) (152 - 30) Singh VB, Khan AAK, Patil PR, Ashraf SN. Cryogenic Engines. Stage 2: = 29.28 kJ/kg International Journal of Pure & Applied Research in Engineering and 9. Technology. 2014;2(9):131-135. H2 Rakesh R, Praven N, Prakash E. An Experimental Study of Cryogenic = 30.48 kJ/kg Engine. International Journal of Innovative Research in Science, 10. StageH 3: Engineering and Technology. 2015;4(2). 3 Muthe Y, Mali S, Ambekar S. Study of Cryogenic Rocket engine. = 28.08 kJ/kg International Journal Of Advanced Technology in Engineering Science. StageH 4: 11.2015;3(1):1489-1493. 4 = 15.6 kJ/kg Roy P. Rocket Engine Analysis and its Features on the basis of Cryogenic Technology. International Journal of Research in Aeronautical and Heat removed during compression = 103.44 kJ/kg 12.Mechanical Engineering. 2015;3(11):80-90. ConclusionTotal heat removed = 103.44 + 404.3 = 507.74 kJ/kg Niasar MS, Amidpour M. Conceptual Design and Exergy Analysis of An Integrated Structure of Natural Gas Liquefaction And Production Of Liquid Fuels From Natural Gas Using Fisher-Tropsch Synthesis. Cryogenics. 2018;89:29-41. Mostly in the Cryogenic plant the expenditure is towards energy and raw material (Air), which is available in large amount. 13. 75.Fesmire JE, Johnson WL. Cylindrical Cryogenic Calorimeter Testing of Six Types of Multilayer Insulation Systems. Cryogenics. 2018;89:58- Out of this energy, 92-95% goes towards compression of air. The task of decreasing the temperature by solar operated heat exchanger is done. 14. andKassemi gravity M, Kartuzovalevels. Cryogenics. O, Hylton 2018;89:1-15. S. Validation of two phase CFD models by reducing the intermediate temperature for four stage for propellant tank self- pressurization: Crossing fluid types, scales compressions.Analysis part In additionby calculating to this, decreaseFreon cooler in power is also incorporatedrequirement 15. before moisture separator, which will increase the performance. Salem MKB, Slimani Y, Hannachi E, Azzouz FB,. Salem MB. Bi- based Superconductors prepared with addition of CoFe2O4 for the design of 16. a Magnetic Probe. Cryogenics. 2018;89:53-57 Hence if such a system is incorporated it will be beneficial for the Arora CP. Refrigeration and Air Conditioning. Tata McGraw Hill 17. Publication. 1984. Domkundwar, Arora CP. Refrigeration and Air Conditioning. Citation: Page 10 of 11 Eng 6(1): 1-11. Rama Rao T, Ranjan Ojha P (2018) Modification of Design of Cryo-Oxygen Plant for Improved Performance. SOJ Mater Sci Modification of Design of Cryo-Oxygen Plant for Improved Performance Copyright: © 2018 Rama Rao T, et al.

18.

19. Gupta CP, Prakash R. Engineering Thermodynamics. 23. Air Property Tables & Charts. Thareja BL. Electrical Technology. Khanna Publication New Delhi. 24. Jadefa TS. “Technology Up gradation of Centrifugal Machinery as Used in Cryogenic Plant with Special References to Steel and Fertilizer 20.21. National code of Electrical Engineering 25. Industries”. CMERI. Durgapur Published in Gas News.1990. 22. Jain RK. Machine Design. Khanna Publication New Delhi. Roy SL. Minimum Economic Size of Oxygen Plant. International Raman K. HMT Data Book. PSG college of Technology, Coimbatore. Industrial Gases Ltd. Calcutta Published in Gas News. 1990. 1998-1999. 26. Rama Rao T. Master of Engineering in Energy System & Pollution

Citation: Page 11 of 11 Eng 6(1): 1-11. Rama Rao T, Ranjan Ojha P (2018) Modification of Design of Cryo-Oxygen Plant for Improved Performance. SOJ Mater Sci