Portable OxygenGenerating DeviceDesignMembrane and Pressure Swing AdsorptionTechnology Alternatives and Market Analysis

Oxygen Design GroupAdam Bortka TJ Chancellor Jon Demster Ashlee Ford Eli Kliewer Kara Shelden

Introduction andMotivation

Oxygen TherapyHypoxemia: Lungs provide insufficientoxygen to bloodstream Oxygen treatment prescribed by aphysician Elderly and disabled persons are mostfrequent users of portable oxygen devices Oxygen flow rates range from 0.5-8 L/min

Existing TechnologiesCompressed Oxygen Tanks Liquid Oxygen Oxygen Concentrators

Compressed Oxygen Compressed oxygen is delivered topatient in pressurized tanksNo electricity, lightweight, high flowrates ( 5 L/min)High purityLimited life of tanksFrequent tank replacementHigh-pressure tanks are hazardous

Liquid Oxygen Large, stationary tank at homeUser can fill smaller, lightweight(5-13 lbs) portable tankNo electricity, high flow rates,quietHigh purityStationary tank must be refilledfrequently by technicianLiquid oxygen will evaporateover time

Oxygen Concentrators Electric oxygen systemProvides oxygen byextracting it from the airGenerally use pressure swingadsorption with zeolitesUnlimited oxygen supplywhile connected to powersourceNo refilling needed

Oxygen Concentrators Most are not portableSize of a large suitcaseWeight is greater than 50 lbs.Requires 250-400 W of power Motor increases electricity costs Motor is loud ( 50 decibels) Requires backup power

Oxygen ConcentratorsOxygen purity ranges from 90-95% Flow rates range from 1-5 L/min Unable to achieve high oxygen flow rates( 5 L/min) Cost from 3,000- 5,000

Oxygen Concentrators Lifestyle portable oxygen concentrator iscurrently on the marketUses molecular sieve technology combined withan oxygen conserving technologyDimensions are 5.5 in x7.5 in x16.5 inWeighs 9.5 lbsAC, DC (automobile), and battery powered

Oxygen ConcentratorsFlow rates range from 1-5 L/min Only 90% 3% oxygen purity Produces 55 decibels Battery life only 50 minutes Takes 2-2.5 hours to charge battery Costs approximately 5,000 Recalled, but still on market

Product Goals Current portable oxygen devices must beimproved to increase performance and reliabilitySolid-oxide membrane and pressure-swingadsorption technologies will be investigatedDevelop a new portable oxygen devicemeasuring 12”x7”x7” capable of achieving a 5liter/minute flow rate and 94-99% oxygen purity

Product Goals6 hour battery life 40,000 hour service life Less than 10 lb. in weight Low noise output Less than 2,000 unit production cost

Pressure SwingAdsorption Design

Pressure Swing Adsorption System of two packed columns withcomponent-selective zeoliteTwo stages in alternation:1.2. Adsorption/ProductionBlowdown/PurgeTurn two batch-phase processes into onecontinuous production processRequires compression of feed stream

Nitrogen Removal DesignEquations Multi-Component Adsorption Isotherm(Langmuir-Freundlich)qi Qmaxbi PiN1 b j Pjj 1

Nitrogen Removal DesignEquations Equilibrium-dominated (assume very fast masstransfer)QF cF t x q F MLx / LB QF volumetric flow rate of feedcF concentration of solute in feedtx time front has traveled at LxqF loading per mass of adsorbent in equilibrium with the feed concentrationS total mass of adsorbent in the bedLx position in the bed, less than or equal to total bed lengthLb length of bed

Specifications Production time of no less than fifteenseconds (total cycle time of thirty seconds) Column diameter of 2.5”

Results2.1 lbs. Oxysiv 5 (13-X zeolite) adsorbentper column 2 columns of 2.5” diameter & 1.5 ft. height Product: 95% O2 5% Ar Removal of argon still required to achieve99% purity

Air DryingMoisture in air acts as poison to Oxysiv 5 Water cannot be desorbed in the samecycle as nitrogen Silica gel used to remove moisture from air Gel regenerated by heat

95% O25% ressureStorageExhaustNitrogenSilica r

Argon Removal Options1.Equilibrium based PSA2.Kinetic based PSA

Equilibrium-based PSAFeed of 95% O2 5% Ar @ 10 atm Increase purity to 99.7% O2 with Argonadsorption on silver mordenite (AgM) Requires moderate heating (30 C) Low selectivity necessitates longer beds orlonger cycle times Approximately 20% recovery

Langmuir-Freundlich AdsorptionIsotherms on AgM

Rate-difference based PSAUse carbon molecular sieve to adsorboxygen Rate of adsorption of oxygen ontoadsorbate is much faster than argon High purity oxygen obtained fromblowdown step

Kinetic Separation DesignEquations Linear Driving Force Model( q 15 De q Rp q2 tRp )t timeDe effective intraparticle diffusivityRp radius of particleqRp loading at particle surfaceq average loading of component on the adsorbent

Operating ConditionsAdsorption at 2 atm Blowdown at 0.2 atm 99.0% pure oxygen 55% recovery 0.01157 kg product/hr / kg adsorbent

Adsorption Data

Equilibrium or Kinetic? Carbon molecular sieve separation will yieldacceptably pure oxygen with a higher recoverythan AgM equilibrium based PSA.Molecular sieve separation will also be lessenergy intensive (smaller pressure change, noheating required)Molecular sieve separation is the most attractiveoption for PSA based oxygen & argonseparation

Results from Kinetic Separation74 lbs. adsorbent per column required for5 L/min 2 columns of 6” diameter and 4.5 ft height Feed rate of 9.9 L/min Product rate of 5 L/min, 99% O2 at 1 atm.

Exhaust ArgonArgonRemovingColumnArgonRemovingColumn95% O25% Ar99% O2VacuumPumpArgonRemovalPurgeCompressor

Impact on Nitrogen RemovingSectionRequired production of 9.9 L/min Assuming 10% of product used as purge,requires initial air feed rate of 79.2 L/min Feed compressed initially to 45 psia. Product pressure let down to 2 atm beforeentering argon removing section

PROBLEM!Device is too heavy and too large to beportable No demand for non-portable device thatonly provides for one user Device must be modified to be useful tooxygen patients

Solution: Compressed Oxygen Patients use small cylinders filled withhighly compressed 99% pure oxygen

Compressed OxygenCylinders (E-size) filled to 2200 psi andprovide oxygen without power source Can provide any flow rate At flow of 5 L/min, 1 cylinder lasts about205 minutes

Compressed OxygenCylinders are not reusable Patient has new cylinders delivered bycompany Patient must work around deliveryschedule Patient limited by number of cylindersdelivered

Market NicheCurrently, no device exists that allowspatient to refill cylinders with 99% pureoxygen An un-fulfilled demand exists for amodified version of our device that allowsin-home cylinder bottling Eliminates need for delivery company

Modified DeviceMust pressurize product Product stored in high-pressure storagetank to allow rapid filling of cylinders Storage tank capable of filling 2 cylindersat a time

High-Pressure StorageH-size aluminum cylinder Volume: 58 L Initial pressure: 3021 psi Final pressure: 2500 psi Allows small amount of emergency oxygenEnsures higher pressure than small cylinder

High-Pressure StorageTank connected to cylinder by ¼” diameter6” long smooth pipe Fill times: 1st cylinder: 5.1 seconds2nd cylinder: 5.2 seconds

orage99% O2

User needs So long as user does not breathe more than 5 L/mincontinuously for 413 minutes (6 hrs 53 minutes), devicecan produce as fast as user consumesBreathing rate (L/min)Minutes to use up small tankHours to use up small tankMinutes to use up both tanksDeadtime for 44.25.7688.4275.42.0516.38.61032.7619.6

Final Product Produces 99% pure medical O2Allows user to refill E-size oxygen cylinders 2 ata time (based on average continuousconsumption of 5 L/min or less)Non-portable, A/C poweredEnough silica gel to dry one bottling cycleGel regenerated by heating element embeddedin canister

Power Requirements 4 CompressorsFlow rate(L/min)Inlet Pressure(psi)Outlet Pressure(psi)Duty(hp)8014.7450.5Purge Vacuum7.98729.42.940.0248Purge Compressor2.98714.729.40.1429514.730213Feed CompressorStorageCompressor

Power RequirementsTotal Power Consumed: 2.74 kW (3.67 hp) Assume device is producing only 12 hoursper day Monthly power consumption: 1018 kWh Operating cost per month: 76.03 Much less than 300/month charged bydelivery companies

Exhaust Argon95% O25% a GelDryingColumnFeedAirHighPressureStorage99% O2VacuumPumpFeedCompressorPurgeCompressor

Parts BreakdownWeight N2 removal Ar removal Combined Weightslb/ft2ft2ft2Total Weight (lbs)MetalAdsorption Columns (Sch. 40 Aluminum)1.52.1314.8825.511.51.131.70Low Pressure Storage Tank (Sch. 40 AlumDryer canister (Sch 40 Aluminum)1.52.303.45Frame (Steel)310.0030.00Piping1/2" Sch. 40 Copperlb/ft0.75PackingOxysiv 5 adsorbentCMS packingSilica Gel drying gellb/column2.1744.9ItemsFeed CompressorVacuum PumpPurge CompressorTank fill CompressorHigh Pressure Storage TankFan3-way solenoid valveCheck valveComputerCasingTotal Final umns221Number ofitemsNumber ofitems1222111111222Total Weight (lbs)6.75Total Weight (lbs)4.20148.004.90Total Weight 525.51

Parts BreakdownMetalAdsorption Columns (Aluminum)Low Pressure Storage Tank (Aluminum)Dryer canister (Aluminum)Frame (Steel)PriceN2 removal Ar removal Combined Costs /ft2ft2ft2Total Cost1.52.1314.88 25.511.51.13 1.701.52.30 3.45230.00 60.00Piping1/2" Sch. 40 Copper /ft3.6125ftPackingOxysiv 5 adsorbentCMS packingSilica Gel drying gel /lb5.532lbItemsFeed CompressorVacuum PumpPurge CompressorTank fill CompressorHigh Pressure Storage TankFan3-way solenoid valveCheck valveComputerCasingTotal Final Cost /item2301001502500150586202040ftTotal Cost6 32.51lbTotal Cost 23.16148 444.00 9.8034.214.9Number ofitemsNumber ofitems1222111111222 Total 0020.0040.004,234.13

Final Sizes Compressor boxHeight: 15”Width: 30”Depth: 25” Column TowerHeight: 55”Width: 21”Depth: 12” Complete DeviceHeight: 55”Width: 30”Depth: 37” (base), 12” (tower) Slightly smaller than a regularfreezer/refrigerator

Membrane Design

Membranes Semi-permeable barriersUse the differences in the abilities of thecomponents to pass through the membranePermeatePasses through the membraneEnriched in the fast component RetentateDoes not pass through the membraneEnriched in the slow component

Membrane General Equation The general equation for flux of component ithrough a membrane is given byNi Pi( driving force )lPi is the permeability of component i through themembrane materiall is the thickness of the membranethe driving force required to induce the flux varies formembrane applications and materials

Membranes for Gas Permeation PolymersUsed industrially to produce N2 from air Ceramic OxidesCan produce a high purity oxygen stream athigh temperaturesMixed Conducting Conducts ions and electronsIonic Transports ions

Polymers for Oxygen Separationfrom Air Polycarbonate is very selective membrane material (7.4702/N2) with permeability of 1.36E-10 cm3(STP) cm/ cm2 scmHgFor 100% recovery of O2, the maximum concentration is88%For a portable sized device, recovery of oxygen is 10%Countercurrent permeate stream 40% oxygenThe feed flow rate requirement can be reduced ifconcentration is decreasedDesign is a tradeoff between oxygen concentration andfeed flow rate

Design Enhancement Options Cascades can be used toincrease compositionThe size of the designincreases significantly with theeach series modulePurge stream can reduce partialpressure on the permeate sideThe purge stream enhances theflux of oxygen but contaminatesthe permeate stream

Polymers for Argon Separationfrom 95% Oxygen PSA Stream TMPC and PPOOxygen permeability: 3.98E-10 and 1.14E-09cm3(STP) cm/cm2 s cmHgOxygen/argon selectivity: 2.43 and 2.28The operating pressures are 3 atm on thefeed side and 1 atm on the permeate side 40 micron membrane thickness

Polymers for Argon Separationfrom 95% Oxygen PSA Stream Using a single membrane module, the highest permeateoxygen concentration is 97.35% using TMPCThe concentration is limited by the low partial pressuredifference, i.e, both concentration and pressuredifferences are lowThe permeation rate is low so recovery is smallFor a module with diameter of 7.48 in. and height of10.24 in., 1300 lpm of feed are required to produce 5 lpmof oxygen productThe device size increases as the feed flow rate isdecreased

Ideal Polymer Membranes Hypothetical membrane with permeability of TMPCselectivity of 7.75 for oxygen, then 99% purity could beobtained in a single moduleFlow rate considerations are still a factorFor a reasonable feed flow rate of 15 lpm, the deviceshould be 8.2 ft. in diameter and 3,281 ft. long which isapproximately 2.5 times the height of the Empire StateBuilding

Mixed Conducting Membranes LSCF ceramicFeed pressure of 1 atmVacuum pressure of 0.01 atmOperating temperature 1273 KOxygen permeate flux is 0.00225 mol m-2 s-1Oxygen recovery from the feed is 95%Need 16,500 cm2 membrane area to produce 5lpm

Ionic Ceramic Oxide MembranesElectrically driven by an external voltagesource High temperatures Only allow oxygen flux Driving force is independent of thepressure

Ionic Ceramic Oxide MembraneOperating Principle

Ionic Conducting Ceramic Materials Yttria-stabilized zirconia (YSZ)most commonly usedtemperature range is 800-1000oC Doped ceriaOxygen-deficient perovskitesBIMEVOX ceramicsbismuth vandates with metals such as zinc, copper, and cobaltsubstituted for portions of the vanadiumoxygen flux similar to YSZtemperature range is 400-600oCreduces the requirements for heating the cells, cooling theexhaust streams, and insulating the apparatus

BIMEVOX Boivin, et al studied the performance of differentBIMEVOX electrolytesBICUVOXBICOVOXBIZNVOXall three exhibit current densities up to 1 A/cm2 Xia, et al report that BICUVOX.10 ionicconductivities are 50-100 times higher thanother solid electrolytesBICUVOX.10 is chosen as the electrolytematerial

Modeling of MembranePerformanceUsed experimental results for BICUVOX Electrochemistry equations used to designthe membrane Specified the desired volumetric flow rateof oxygen Chose number of membrane plates andtheir thickness

Membrane Current Faraday relationship used to determine thecurrent requirement4QFI n4 is the number moles of electrons required todissociate 1 mole of oxygen moleculesQ is the molar flow rate of the oxygen permeateF is the Faraday constant, 96485 C/mol electronsn is the number of membrane sheets.

Membrane Area Area required is based on the current density ofthe membrane materialBICUVOX.10 at 585oC has a current density ofapproximately 0.75 cm2/AThe current multiplied by the current densitygives the membrane area requiredTotal membrane area is divided by the numberof sheets gives the area of each sheetThe model equations assume that each sheet issquare

Membrane Voltage The voltage drop across each membrane, E, iscalculated using the Nernst potential,RT yO2 ,hlnE zFyO2 ,lR is the ideal gas constantT is the operating temperaturez is the number of electrons required per ionF is the Faraday constantyO2 is the concentration of oxygenthe subscripts h and l refer to the high and low concentrationsides of the membrane

Total Device Components Membrane StackHeating ElementHeat ExchangersInsulationPumpsBatterySealantCase

18 lb. Device

Membrane Design Initial design: 9 plates (5.5” x 5.5”) Current 149 A Voltage 0.52 V Power 76.7 WIM4QF n-To reduce the amps, a differentconfiguration was suggested. New design: 48 plates (2.4” x 2.4”) 4 stacks with 12 cells per stack Current 28 A Voltage 2.75 V

Membrane DesignCalculationsnumber of plates48platestotal volumetric flow rate of permeate5L/minmolar gas volume (STP)24.04L/molelectron stoichiometry4mol electrons/mol O2current27.868Acurrent density for BICUVOX.100.75A/cm2thickness of plates0.38cmair gap height0.75cmelectrode height0.2cmnumber of columns4height per column9.85involume of plates41.36in3density of ceramic*0.21lb/in3mass of ceramic8.60lbtotal potential for stack2.751Vpower required76.675Woxygen recovery from feed0.80feed flow rate30L/min

Additional Design CriteriaIM4QF nRT yO2 ,hlnE zFyO2 ,lNernst equation determinesvoltage across each membraneThe density of Bicuvox was estimated at5.75 g/cm3 based on the densities of thesimilar ceramic materials Y-TZP, VanadiumCarbide, and Zirconia.

Cell Stack Design Magnesium Oxide Housing

Heating Element The ionic conduction membrane beginsconducting at 585 oC Nichrome-60 heating element 3 wires 4.8” long located in inlet air stream Heating element power is 66 W

Heating Element Criteriawire design: 3 vertical wires along the feed streamwire length/air entry point4.80incurrent/length of wire to heat wires to 585 C4.58A/ftcurrent for 3 parallel sets of resistors inparallel, IH5.50Aresistance/length of wire1.82ohmresistance of each wire0.7276ohmprice/length of wire0.80 /ftprice of wires0.96 weight/volume of wire0.30lb/in3diameter of 24 gauge wire0.20intotal weight of wires0.36lbequivalent resistance of 3 wires in parallel, RH2.18ohmassume start up time20min

Heat Exchanger Membrane stack operates at 600ºCIncoming 30 L/min feed air stream used to coolexiting 5 L/min oxygen and 25 L/min nitrogenstreamsTwo microchannel heat exchangers neededOxygen and nitrogen streams both exit theexchangers at 41ºC, and the feed enters the stackat 580ºC

Oxygen & Air ExchangerCopperMass 0.15 lbs 20 channels total (10 on top,10 on bottom)Each channel is 0.4 in. high,0.31 in. wide, 7.9 in. longSurface area 0.56 ft2Reynolds number 19Velocities 10.4 cm/sRetention time 1.9 sec.

Nitrogen & Air ExchangerCopperMass 0.24 lbs 40 channels total (20 ontop, 20 on bottom)Each channel is 0.7 in.high, 0.37 in. wide, 10 in.longSurface area 2.9 ft2Reynolds number 34Velocities 12.9 cm/sRetention time 1.9 sec.

Method Required heat transfer area was found from doublepipe exchanger overall heat transfer coefficientAir and oxygen 0.11 ft2Air and nitrogen 1.8 ft2 Dimensions of each exchanger were found byvarying the length, width, and height of eachchannel while simultaneously varying the number ofchannels to achieve the required surface area foreach deviceOuter wall thickness set at 2.5mmMiddle layer thickness set at 0.5mmWidth between each channel also specified as0.18mm

Pressure Drop Correlation for laminar flow in rectangularducts.4kL m 2 P 2 Re d eq Ac2 ρk f Re 24(1 1.3553α 1.9467α 2 1.7012α 3 0.9564α 4 0.2537α 5 )α channel heightchannel widthTotal stream pressure drops negligible 10-4psi

Sealant PurposeSeparation of gas streamsin membrane stack Required attributesNo harmful vaporsMust withstand operatingtemperaturesThermal expansionproperties

Sealant Resbond 907GFNo known health effectsUsable temp. range up to 1288ºCThermal expansion elongation, 5%closely matches expansion of housing and cells prevents leaks Electrically insulating; high resistivity

Insulation Heat ShieldingMetal foilLocation: between cell membranes and housingPurpose: negate radiative heat transfer 97 to 99% effectiveMembrane Stack InsulatingVacuum panels: for low thermal conductivityLocation: external face of heat exchanger housingPurpose: insulate unit from membrane cell stackoperating temperatures

Vacuum Panel Insulation Vacupor by PorexthermCore material: fumed silicaNecessary to prevent panel collapse Prevents out-gassing at low pressures No degradation of vacuum No health issues associated with conventionalinsulationLow thermal conductivity constant: k 0.0048 W/mK

Vacuum Panel Insulation q Fourier Eq.Newton’s Law ofcoolingT1 - T5 x M gO A k M gO- kMgO 30 W/mK- kVac pnl 0.0048 W/mK- Housing: 0.5cm thick- Vacuum panelthickness: 7.5cm-Hot face temp: 585ºCGives cold face temp. of27.1ºC (80.7ºF) x vac 2 A k vac hair

Feed CompressorsProvides feed air to the membrane stack Desired Attributes Feed Air Requirements 28 L/min to achieve 5L/min oxygen flowLow power requirementsSteady flowSmall sizeLow weightNo particle/lubricant emissions

Thompson CompressorG12/07-N Rotary Vane- 18.5L/min flow rate @ 1.0psi-2 pumps combined flow:37L/min- 12V DC- Weight: 1.1 lb.- Oil-less- No pulsation- Low vibration- 2.00 x 4.45 x 2.25 inches

Power Supply Lithium-Ion battery12V DCFull charge operating time: 4 hrComplete recharge in 3 hrs 95% charge in 1.5 hrsHigh energy density: 400 Wh/L Results in low weight and volume1.81 lbs0.31L

Controls and Alarms Safety and Product Stream QualityTemp Alarms High product stream tempFlow Rate Control Regulation of the oxygen stream for patient activitylevelLow Voltage Alarm: battery low warningAudio and Visual Alarms: for audio or visuallyimpaired users

External Casing AluminumLow costLow density: lower unit weightHigh durability to impacts, corrosionNo health concerns associated with plastics Heat exposure

Prototype CostComponentCost ( )BasisInconel electrodes30.00assuming one lb per unit; based on raw materialcostBatteries150.00hardware store costBattery charger50.00actual costResistance heating wires1.00 0.80 / ftVacuum insulation50.00estimate from conventional insulationFoil radiation shielding0.50 100 per 1000 ft2Heat exchanger1000.00estimateExternal Casing50.00estimated from manufactured aluminum casesControls and alarms100.00estimatePumps (2 ea)468.00Thompson pumps distributor; cost for twoCeramic BICUVOX500.00pure estimate, based on manufacturing processTotal Unit Cost 2500


Medical CoverageCosts range from 300- 500 per month forportable oxygen treatment Covered by most private insurancecompanies and HMOs Medicare covers 80% of costs ifprescribed by a doctor Not covered by Medicare if used onlyduring sleep or as supplement tostationary oxygen system

FDA Approval Sec. 868.5440 Portable Oxygen GeneratorReleases oxygen for respiratory therapy by physical means or bya chemical reaction Class II deviceSubject to Pre-market Notification [510(k)]Class I and II devices must submit a 510 (k) at least 90days before marketing in the United StatesStandard fee of 3,502Total average review time for fiscal year 2003 was 96days (including wait time)

Pre-market NotificationMust prove substantial equivalence (SE)to a previously approved similar device Must be as safe, effective, and intendedfor same use as similar device Device can be marketed in the U.S. oncesubstantial equivalence is proven true byFDA

Pre-market Notification New Technology is considered SE if:New device has same intended use, ANDHas new technology that could affect safety oreffectiveness, ANDThere are accepted scientific procedures fordetermining whether safety or effectiveness has beenadversely affected, ANDThere is data to prove that safety and effectivenesshas not been diminished

FCI Estimation andPrice Determination

Basic Economic ModelαP1d1 βP2 d 2 P Price d Demand α Fraction of our market that has knowledge ofour product Based on happiness; fraction that will preferour product β

Alpha Function The alpha function describes how long it willtake in order for our market to learn about ourprojectAdvertising, contracts with distributors andmarket type all are factors in the alpha function y *t α ( y, t ) 1 y *t 1

Effects of Advertising on TheAlpha FunctionAlpha Function With Varying Advertising Levels10.90.8Alpha0. Advertising0.30.2Medium Advertising0.1High Advertising00246Years810

Beta Function The beta function describes the likelihood that aconsumer will choose to buy our product.The happiness ratio of the two products and timeare factors included in the beta function Ht B(k, t ) 1 k1 Ht 1

Effects of the Happiness Ratioon the Beta Function10.90.80.7Beta0. Low High0246Years810

Happiness Determination Happiness was found from a series of factorsby comparing the properties of our productsto their maximum or minimum valuesFor example comparing battery life:Min acceptable life: 30 minMax possible before indifference: 6 hrsMembrane battery life: 5 hrs

Happiness DeterminationDeviation from the minimum was found for eachfactorEx:5hr .5hrDev 0.816hr .5hr

Happiness DeterminationDeviations were weighted and summed Competing with AirsepHappiness oisePurity of AirAppearanceBattery lifeVariable Flow-ratesImportancenormalizedweight xiour deviation 3000.6671.000Our HappinessCompetitor 90.0710.0000.0240.0000.0070.0200.0290.5040.310

Potential Demand The total demand for new consumers inneed of the our products concentratorswas estimated at 12,000 per year

Competitors Airsep Lifestyle Airsep Refiller (95%)

Price DeterminationFirst settingandβγ αd 2 D d1and then solving for the expected demand for our productγP2 Dd1 P1 γP2

Price DeterminationPrice was adjusted and FCI and NPW wasfound for each price Plant capacity was found using the highestdemand level The price resulting in the highest NPWwas chosen as the selling price

TCITCI wasfound as afunction ofdemandCapital Investment for Portable Oxygen DeviceDirect CostsPercent of Equipment Cost100Purchased equipment delivered45Purchased-equipment installation18Instrumentation and controls16Piping10Electrical systems25Buildings15Yard ImprovementsService facilities40Total direct plant cost 28,500,000 12,825,000 5,130,000 4,560,000 2,850,000 7,125,000 4,275,000 11,400,000269 76,665,000333941735 9,405,000 11,115,000 1,140,000 4,845,000 9,975,000Total indirect plant cost128 36,480,000Fixed Capital Investment397 113,145,000Working Capital (15% of total capital investment)70 19,966,765Total Capital Investment467 133,111,765Indirect costsEngineering and supervisionConstruction expensesLegal expensesContractor's feeContingency

Net Present Worth The NPW was calculated from TCI and demandfor each selling ,6485,8886,0736,2206,339Sales ( /year) Product Cost Gross Earnings Depriciation TaxesNet ProfitCash FlowCFn/((1 r) n) 62,449 184,088- 121,640 110,103 2,186- 231,743- 123,825- 112,568 36,150,577 8,632,836 27,517,741 110,103 1,265,270 27,407,638 26,252,471 21,696,257 51,838,293 12,305,555 39,532,738 110,103 1,814,340 39,422,635 37,718,398 28,338,391 60,770,652 14,396,748 46,373,904 110,103 2,126,973 46,263,801 44,246,931 30,221,249 66,553,383 15,750,568 50,802,815 110,103 2,329,368 50,692,712 48,473,447 30,098,197 70,605,882 16,699,316 53,906,566 110,103 2,471,206 53,796,463 51,435,360 29,033,920 73,604,595 17,401,358 56,203,238 110,103 2,576,161 56,093,135 53,627,077 27,519,170 75,913,616 17,941,932 57,971,684 110,103 2,656,977 57,861,581 55,314,707 25,804,719 77,746,497 18,371,036 59,375,461 110,103 2,721,127 59,265,358 56,654,333 24,026,968 79,236,822 18,719,942 60,516,879 110,103 2,773,289 60,406,776 57,743,591 22,262,654AvgAvgSum 45,097,836NPW 43,134,249 216,626,303 223,989,101Straight line depreciation was assumed with aninterest rate of 10%

N P W (m illio n )Optimum Selling 000Selling Price ( )15000

Limitations of the modelThe model is not accurate when the sellingprice of our product is much greater thenaverage market selling price Solution: adjust beta function to lowerdemand faster at high prices

Adjustment of the Beta FunctionThe beta function was adjusted toincrease as the selling price approachedand passed the twice the value of ourcompetitors.p1 1 . 5 , then with k inversely related Ifp2to happiness pB Bo 1( k p2 )

Optimum Selling PricesDevice95% Oxygen 99% OxygenConcentrator Tank FillerSellingPrice 1800 18,500(Base) 11,000 27,000 (withelectricity)TCI 4.7 million 80 million 133 million 105 million 166 millionNPW 3.4 million(10 years)MembraneConcentrator

Suggested Improvements ToEconomic Model Offer to rent the tank filling device at amonthly rateExtensive market research should beconducted to improve happiness factors andweight ratiosPrice of advertising vs. benefit of advertisingMore accurate FCI calculations

ConclusionsA 99% oxygen tank filling device usingpressure swing adsorption technology wasdesigned and would be more economicalthan home delivery A portable ceramic oxide membranedevice was designed to give 5 lpm of 99%oxygen with 4 hours of battery operation

ConclusionsMembrane concentrator is the best optionbased on purity and portability PSA tank filler offers an immediately viablealternative while membrane concentratorprototype undergoes testing and approval


User needs So long as user does not breathe more than 5 L/min continuously for 413 minutes (6 hrs 53 minutes), device can produce as fast as user consumes Breathing rate (L/min) 5.0 4.0 3.0 2.0 Minutes to use up small tank 206.5 258.2 344.2 516.3 Hours to use up small tank 3.4 4.3 5.7 8.6 Minutes to use up both tanks 413.1 516.3 688.4 1032.7 Deadtime for device 0.0 103.3