refrigeration (kylteknik) - Åbo akademiusers.abo.fi/rzevenho/ref17-oh5.pdf · reversed brayton...

5. Low temperatures, liquefied gases, Stirling engines, LNG, dry ice

Ron ZevenhovenÅbo Akademi University

Thermal and Flow Engineering Laboratory / Värme- och strömningstekniktel. 3223 ; [email protected]

Refrigeration (Kylteknik) course # 424519.0 v. 2017

ÅA 424519 Refrigeration / Kylteknik

12.2.2017Åbo Akademi Univ - Thermal and Flow Engineering Piispankatu 8, 20500 Turku 2/84

5.1 Gas refrigeration and liquefaction


Gas liquefaction options Liquefied gases can be produced by cooling a gas until

it partially forms a liquid, and removing this liquidproduct, by gas-liquid separation.

The necessary cooling effect can be achieved by expansion cooling– Using a turbine or other expansion machine

(allows for very limited liquid formation): reversed Brayton cycle, reversed Stirling cycle

– Using a throttling device, making use of the Joule-Thomson effect

For pre-cooling, a vapour- compression process can be used

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5.2 Stirling cycles

See also A11: chapter 13.10and TV08


Carnot, Stirling, Ericsson cycles Carnot cycle: reversible

– Heat addition at constant T– Adiabatic expansion– Heat rejection at constant T– Adiabatic compression

Stirling cycle: reversible– Heat addition at constant T– Heat rejection at constant v– Heat rejection at constant T– Heat addition at constant v

Ericsson cycle: reversible– Heat addition at constant T– Heat rejection at constant p– Heat rejection at constant T– Heat addition at constant p

T,s and p,vdiagrams for Carnot →and Stirling ↓power cycles

12.2.2017 Åbo Akademi Univ - Thermal and Flow Engineering Piispankatu 8, 20500 Turku

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Stirling cycle, Stirling engine

Heat is temporarily stored in the regenerator, going from temperature TH to TL during step 2-3 (and vice versa when returning to state 1) Picture: T06Picture: ÇB98

See for principle also http://www.cs.sbcc.net/~physics/flash/heatengines/stirling.html (Feb. 2017)


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A Stirling cooler

“The cooler consists essentially of only two moving parts - a piston and a displacer. The displacer shuttles the working gas (helium) between the compression and expansion spaces. The phasing between the piston and displacer is such that when the most of the gas is in the ambient compression space, the piston compresses the gas while rejecting heat to the ambient. The displacer then displaces the gas through the regenerator to the cold expansion space. After this, both displacer and piston allow the gas to expand in this space while absorbing heat at a low temperature.”

Picture and source: http://www.ohio.edu/mechanical/thermo/Intro/Chapt.1_6/Chapter3b.html (Feb 2017)

TL

TH


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Stirling refrigeration cycles /1

The working gas in the cycle is hydrogen or helium (high thermal conductivity!)

The Stirling cycle is difficult to achieve in practice since heat transfer requires temperaturedifferences→ regenerator has efficiency< 100%, and pressure drop

Nonetheless of interest due to efficiency potential and (for engines) emissions control(Ford, GM, Philips)

Picture: S90Stirling gas refrigerator (Philips)


Stirling refrigeration cycle /2

Stirling refigeration devices(”cryogenerators”) allow for cooling down to -250°C at up to several MW cooling power

Efficiency: COP ~ 0.5· COPcarnot

Compact, simple, low noise Temperature-range flexible

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Evaporation

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Claude

Joule-Thomson

With repeated strokes, lower and lowertemperatures can bereached



5.3 Joule-Thomson effect(see also 3.3)

See also A11: chapter 2.30


Gas expansion: Joule-Thomson effect /1

Throttling (= isenthalpic pressure reduction of gases) can have a temperature effect as a result of deviations from ideal gas behaviour:

For the states (for example in a T,s diagram) where(∂T/∂p)h > 0, reducing pressure will give a lowertemperature: the Joule-Thomson effect Picture: S90

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Gas expansion: Joule-Thomson effect /2

At the inversion temperature of a gas, µJT = 0

Application: cooling and liquefaction of gases

Some tabelised data:

Picture & table: A83

Air at 1 atm: µJT ~ 2K/MPa at ~ 20°CµJT ~ 4K/MPa at ~ -100°C


Using the Joule-Thomson effect

Note: during vaporisation of liquid air, more N2 than O2 is vaporised, enriching the remaining liquid in O2, whichcan lead to ignition of oil, therefore cooling with liquidnitrogen (by-product from O2production !) is much safer

The main application of the J -T effect is the Linde process, later also the Claude process, still later also natural gas processing: gases with relatively high vapour pressure

Initially used mainly for liquefaction of air, followed by distillation to separate air into N2 + O2

Water and CO2 can be removedat ~ -50°C and -80°C, resp.

T,x diagram for O2 + N2 at 1 atm

Picture: Ö96



5.4 Linde-Hampson process(for liquefaction of gases)

See also A11: chapter 13.11and MMW14: chapter 4..2.5


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Linde-Hampson process – ideal /11-2 Compression at T = Tin

2-3 Heat exchange3-4 Throttling4-6 Liquid removal4-5 Gas removal5-7 Heat exchange

Note: massin = massliq @ 6 + massgas @ 5

1 and 7 can be open forair (and p2 for cold gas = 1 bar); closed loop for other gases

Liquefied gas

Picture: S90

heat exchange


Data for several gasesCritical Temperatures, Critical Pressures, Boiling Points

Gas Tc(oC) Pc (atm) BP at 1 atm (oC)

He -267.96 2.261 -268.94

H2 -240.17 12.77 -252.76

Ne -228.71 26.86 -246.1

N2 -146.89 33.54 -195.81

CO -140.23 34.53 -191.49

Air -140 39 see data N2, O2, …

Ar -122.44 48.00 -185.87

O2 -118.38 50.14 -182.96

CH4 -82.60 45.44 -161.49

C2H6 32.27 48.16 -88.6

CO2 31.04 72.85 -78.44

C3H8 96.67 41.93 -42.02

NH3 132.4 111.3 -33.42

Cl2 144.0 78.1 -34.03


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Linde-Hampson process – ideal /2Mass balance:min = m4 = m6 + m5

Energy balance I:h3= h4 = x· h5+(1-x)· h6

fraction of massliquefied = γ = 1-xEnergy balance II:m2· h2 = m6· h6+m7· h7

h2 = γ· h6 + (1-γ)· h7

givesγ = (h2-h7)/(h6-h7)

Liquefied gas

Picture: S90

heat exchange

II

I

Note: ΔT23 < ΔT57


Linde-Hampson process – ideal /3 For example (see p,h

diagram on next page) air 290 K, 1 bar → 200 bar hair in = 290 kJ/kg = h4

h1 = 255 kJ/kgh2 = - 40 kJ/kg = h3

h3’ = -130 kJ/kg

air mass fraction liquefied,γ, from energy balance

min· h1= γ· min· h3’+ (1-γ)· min· h4

gives γ = (h1-h4)/(h3’-h4) = 0.083 kg / kg

T2 = 120 K, T3’ = 80 K

Picture: Ö96

cp kJ/kg· K 1 bar 300 bar

0°C 1.006 1.409

-100°C 1.011 1.761

Some data for air:

CompressorCooler after compressor

Heat exhangerThrottling and liquid removal

1

3

2

4

3’

3’’

(see also Ö96 – example 6.4)


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Linde-Hampson process: p,h diagram


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Linde-Hampson process – real states ”*”

1-2* Compression with intercooling

2*-3* Heat exchange with pressure drop

3*-4* Throttling4*-6* Liquid removal4*-5* Gas removal5*-7* Heat exchange

4* instead of 4: much less liquid product !Cooling inlet compressionwith water can give 1-2With air, if 7 ≠ 7* then coldair is rejected.

Picture: S90

Liquefied gas


Linde-Hampson process - improved Linde process

with pre-cooling using a separate refrigeration process

Linde process with external pre-cooling process and high pressure circulation

Pictures: Ö96

to ~50 barto ~200 bar(for air)


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Linde-Hampson initial cascade process

Until 1895 the mostimportant process, used only for liquefaction of air

Uses 4 cooling cyclesin series

Relatively small pressure & temperature rangesper stage

Medium is liquefied in 4th stage

Picture: Ö96

Linde’s 4-stage cascadeprocess (here for N2)

EvaporatorCondenser

EvaporatorCondenser

EvaporatorCondenser

Condenser

Compressor



5.5 Claude process(for liquefaction of gases)

See also MMW14: chapter 4..2.6


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Similar to Linde process except for:

2-3 heat exchange Iand then partially:

3-4 expansion turbine; + 3-5 heat exchange II + III

5-6 throttling6-8 liquid product6-7 gas product

A mix of a Linde process(all flow to throttle) and agas expansion process(no flow to throttle)

If 4 = 7 then heat exchange III is not needed

Picture: S90

Lique-fiedgas

Claude process - idealHeat exchange

IIIIII

turbine


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Claude process – real states ”*”1-2* Compression with

intercooling2*-3* Heat exchange I with

pressure drop3*-4* Expansion with losses$

3*-5* Heat exchange II with pressure drop

5*-6* Throttling6*-8* Liquid removal6*-7* Gas removal7*-9* Heat exchange with

pressure drop

6* instead of 6: much less liquid product !

Cooling inlet compressionwith water can give 2=2*

Picture: S90

Lique-fiedgas

$ depends on expansion device


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Linde-Hampson vs. Claude process For the Claude process the optimisation of the mass streams

and heat exchange is very important The Claude process is more complicated, requires less energy

input as a result of the expansion machine, nonethelessefficiencies can be as low as ~ 4-6 %.

For liquid air the production is ~ 0.05 - 0.07 kg/kg input air, can be improved to 0.1 - 0.2 kg/kg input air when using pre-cooling to -30 ~ -50°C

The temperature after the compressionis very important for overall efficiency

The choice between a Linde or Claude process depends on size and costs

For air, pre-cooling to ~ -50°C for H2O removal, to ~-80°C for CO2 removal

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Liquid O2


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Process energy use The energy input can be

evaluated from an energy balancefor liquid productγ· m· h0 + P = Q + γ· m· h3’with fresh gas feed γ· m at enthalpy h0 and m = mass flow to be compressed.

Power input per kg product: P/(γ· m) = Q/(γ· m) + h3’ – h0

Energy input for producing liquefied air at 80 K at 290 K ambient temperature

Theoretical kWh / kg

In practicekWh / kg

Linde cascade process (4 stages) 0.32 0.54

Simple Linde process 1.21 2.1

Linde process + pre-cooling 0.70 1.2

Linde process + high pressure circulation 0.45 0.63

Claude process 0.35 0.85

PowerP

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0

..

. .

.

Table and picture after Ö96

.



5.6 Liquefied hydrocarbons(LNG / methane, LPG) and CO2

See also MMW14: chapter 4..2.4


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LNG processing /1

Liquefied natural gas (LNG) is becoming increasing important, as a substitute for oil and other fossil fuels; liquefaction facilitates long-distance transport

Methane (CH4) with higher C:H molar ratio than other hydrocarbonfuels, gives less CO2 /kWh power

Typical composition:

CH4 87 - 91 mole-%; C2H6 4 - 11 mole-%; C3H8 < 3 mole-%;C4H10 < 1.5 mole-%; C5H12 < 0.05 mole-%

The gas is delivered for processing at ~ 90 bar and after removal of H2S / CO2, H2O, Hg (!), and heavy components (C5+), it is completelyliquefied at ~ - 160°C, pressures between 1 and 60 bar

LNG can be used to produce CNG (compressed natural gas, 100-250 bar)

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LNG processing /2

Source: WE09

LNG processing

Typical ”train” unit sizeup to 8 MTPA (million tons per annum)

LNG composition

Often, ethaneand/orpropane/butaneare (partly) removed

More detail:MMVW14 Chapter 2


p,h diagram methane CH4 (R-50)

12.2.2017Åbo Akademi Univ - Thermal and Flow Engineering Piispankatu 8, 20500 Turku 31

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LPG Liquefied petroleum gas (LPG) is a liquefied mixture of mainly

(>95%) propane plus some similar boiling point hydrocarbons, mainly butanes.

LPG is produced during processing of natural gas and in crude oil refining

The atmospheric boiling point of propane is ~ -42°C; LPG can be liquefied by compression and cooling to ~ 12 bar at low emperatures, and can be stored at ~ 15 bar, 40°C

Propane Production & Distribution System

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Wobbe index


https://en.wikipedia.org/wiki/Wobbe_index(Feb. 2017)

For LNG: 35 ... 55 MJ/Nm3


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Picture: D03

Similar to LNG and methane,a cascade of compression / heat exchange / expansionprocessescan be used for liquefication of other hydrocarbons with high vapour pressure (ethane, ethylene, ....) and CO2, usinghydrocarbons, ammonia, CO2, ....... as refrigerants

Acetylene, ethylene, CO2, ....



5.7 LNG supply chain and processing

See also MMW14: chapter 1

Depending on transport distance and amount, transport of NG by pipeline, as LNG or after conversion (Fisher Tropsch GTL fuels, MeOH, DME)

2014: ~70% NG transport by pipeline, ~30% as LNGSmall LNG terminals: 0.01 – 0.3 Mt/a (MTPA), large > 1.5 Mt/a. Qatar: > 7 Mt/a, Australia > 8 Mt/a Global LNG trade 2016 ~ 250 Mt/a

Natural /LNG gas supply chain


Picture: MMVW14

LNG processing before transport


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BOG = Boil-Off Gas

Pre-chilling and removal of heavy fractions (C2-C5, C6+), bringing CH4 content from ~90% to ~98-99%

Liquid LNG from flash (to ambinient pressure) to storagetanks, flash gas + BOG from storage and ship is compressedand sold e.g. as fuel

Gas turbinesreplaced steamturbines for LNG refrigeration, less attactiveto use flash gas (recompressionneeded)

LNG production from raw NG

LNG: atm. boiling point ~ -162°C, 87-99% methane, density 430 ~ 470 kg/m3, NG flammibility limits in air LFL ~ 5%-vol, UFL ~15%-vol


N2 removal:1.quality

2. boiling point3. roll-over

Picture: MMVW14

LNG processing: special features Gas composition, purification needs: water, Hg, CO2, N2, ”heavy

hydrocarbons”, H2S Water removal: glycols (DEG or TEG), or adsorbents that also remove

CO2 and H2S, using molecular sieves, or alkanol amines (MEA, DEA, ....) Storage of LNG at ~ -160°C, 1 atm, at 1/600th of the NTP volume

requires, of course, insulation, and removing boil-off Pre-stressed concrete, Al and 9%Ni steel are suitable A serious challenge is stratification, caused by free convective flow of

heated liquid along the walls, towards the upper, liquid-vapour interface. Roll-over can then givesudden and rapid flashing.

”Aging” and varying LNG input increase the risk

More detail / source: F05 (e.g. Section 6.4)


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5.8 Liquefied gas, LNG transport

See also MMW14: chapter 3


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Liquified gas transport

Liquefied gases can be transported while beingrefrigerated on ships, trains and trucks (and in principle also on aeroplanes)

One option is to use part of the boil-off as fuel for the vehicle (and to drive the compressorfor the refrigerator)

Traffic and public safetymay be an issue

See also http://liquefiedgascarrier.com/ (Nov. 2014)

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LNG transport by ship

Typically 30 000 – 300 000 m3, mostly ~ 130 000 m3 ~ 65 000 tons. T = approx. -169 °C, p = 1.3 ~ 1.7 bar, BOG = 0.05 ~ 0.15 %/day


Pictures: MMVW14

LNG transport by ship


Pictures: MMVW14

LNG receiving terminal : model


Picture: MMVW14

LNG receiving terminal: processing


Picture: MMVW14



5.9 Natural gas liquefaction

See also MMW14: chapter 3and WE09: chapter 6

NG cooling curve


Pictures: http://scialert.net/fulltext/?doi=jas.2011.3541.3546&org=11 from article: http://scialert.net/qredirect.php?doi=jas.2011.3541.3546&linkid=pdf

andhttps://www.researchgate.net/figure/289496479_fig1_Fig-1-Pure-and-MR-cooling-curve-in-comparison-to-natural-gas-Helgestad-2009


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LNG liquefaction /1

LNG liquefaction is based on succesivecompression, heat exchange and expansion

Currently the propane pre-cooledmixed refrigerant (PPMR / C3MR) process* → covers ~75% of the market needs since the late1970s

A mixed refrigerant (MR) is used for minimal irreversibility losses; the PPMR process uses a mixture of nitrogen, methane, ethane and propane →

The first steps cool to ~ -35°C to remove heavy components (natural gas liquids, NGL), followed by Joule-Thomson cooling to ~ -160°C* APCI (Air Products & Chemicals Int)

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-35 °C -161°C~ 0.07 bar


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LNG liquefaction /2

An important alternative process for LNG liquefaction is the optimised cascade LNG process (OCLP)* based on threerefrigerants: propane, ethylene circuits and methane (flash) circuit.* Phillips Petroleum Co.

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LNG liquefaction /3

Another important, more recent alternative, process for LNG liquefactionis the the more recent dual mixed refrigerant process (DMR)* basedon pre-cooling to -50°C in the (P)PMR cycle (refrigerant propane) and further cooling and liquefaction in the MR cycle (refrigerant mainly ethane+ propane). Advantages: high efficiency, lowest specific costs. * Shell

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LNG liquefaction /4 Others

Source: WE09

Single mixed refrigerant (SMR) loop process Liquefin™ processMixed fluid cascade process

NG liquefaction power consumption


Table: MMVW14



5.10 Liquefied gas, LNG storage

See also MMW14: chapter 1.4.6


Liquefied gas storage spheres Storage of liquefied gases can be

accomplished at pressures near1 atm using a spherical tank with a free liquid surface

Isolation materials minimise the ”boil-off” gas, BOG typically~ 0.05 % per day

The tank can be considered to be the evaporator of a vapour-compression cycle: the boil-off is extracted, compressed, condensed and throttled to the tank pressure

The two-phase mixture returned to the tank gives a cooling effectthat exactly compensates for heat leaking in during steady-stateoperation

For very low-temperature boiling gases like methane, a cascaderefrigeration process can be used with propane, freons, water, ..

Power

Liquid level

STORAGE

Condenser

Throttle


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Liquefied gas storage Many liquefied gases can be

stored in gas storage spheres at atmospheric pressures, for example air, O2, N2 at ~ -190°C

CO2 is stored at ~ -20°C at 20 bar (triple point at 5.1 bar; if de-pressurised below that it will give a solid : dry ice! )

Ammonia can stored at atmospheric pressure at -33°C

Alternatively, gases can be stored without refrigeration in pressurised gas bottles.

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LNG storage tanks,roll-over

Heat transfer inside LNG storage tank, roll-over


Pictures: MMVW14



5.11 LNG off-loading, regasification

See also MMW14: chapter 1.4.6

LNG regasification /1 At the destination, LNG must be returned to the gaseous state for

transport and distribution, gradual warming from -163°C to > 0°C at 60 ~ 100 bar or more.

Also, to recover energy: ~ 8% of LNG energy is used for liquefaction! If possible, sea-water

trickle-type heat exchangers (made ofwood, or Ti-based metal) are used; if neededsome of the gas is burned to produce heat.

In some cases, contents ofN2 and/or C2+ are adjusted.

See: http://www.saggas.com/en/proceso-de-regasificacion/12.2.2017Åbo Akademi Univ - Thermal and Flow Engineering Piispankatu 8, 20500 Turku 58

LNG regasification /2

Status Finland (Feb. 2017): – Pori: operational September 2016 (storage capacity 0.015 Mt)– Tornio Manga project (to be available 2018)– Porvoo: LNG production operational 2010 (0.02 Mt/a)


Port of Sagunto , (East coast of Spain)Installed capacity1.150.000 Nm3/h

Vaporisers (4x seawater,1x submerged combustor)

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Off-loading: LP compression, BOG condensation, HP compression /1

LP sendoutpumps: ~ 1.3 ~ 9 bar


typical

Pictures: MMVW14


After LP pump 1.3 9 bar, BOG recondenser at ~ 9 bar, followed by HP pump 120 bar


Picture: MMVW14



LP sendoutpumps: ~ 9 ~ 120 bar

typical

Pictures: MMVW14

Regasification / vaporisation /1

Open Rack Vaporisation (ORV) : ~ 70%


Pictures: MMVW14


Submerged Combustion Vaporizer (SCV): ~20%


water

Pictures: MMVW14


Shell-and-tubevaporiser

Intermediate fluid vaporiser process


Pictures: MMVW14


Hydrocarbonheat transfer fluid process


Pictures: MMVW14


Ambient air vaporizer


Pictures: MMVW14


Use of cold with organic Rankine cycle (ORC)closed (left) or open (right)


Pictures: MMVW14

As for yet another optionfor recovery of LNG coldenergy:Stirling engines !



5.12 FPSO: floating production, storage and off-loading for LNG

FPSO floating production, storage and offloading

For example, the Lithuanianfloating storage and regasification unit (FSRU), built for Lithuania’s liquefied natural gas (LNG) terminal at Klaipéda; storage capacity 170 000 m3. (27.10.2014)

Compared to on-shore equipment, besides energy efficiency extra attention to compactness and safety

Mixed refrigerant (MR) processes need less equipment, while pure refrigerant cycles need more stages


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NG liquefaction for FPSO


LNG liquefaction processes for FPSO studied by Lee et al. (2011)

See also: http://www.mustangeng.com/NewsandIndustryEvents/Publications/Publications/ midstream_LNG_Journal_Feb08.pdf (2008) http://www.airproducts.com/~/media/Files/PDF/industries/lng/en-lean-gas-article.pdf (2013)



5.13 Hydrogen

See also http://www.hydrogen.energy.gov (Feb. 2017)


Hydrogen productionHydrogen is (was?) seen, especially by politicians, as a ”solution” to

the ”energy production” and greenhouse effect problems However, hydrogen is not a fuel that can be extracted from

a natural resource but must be producedOptions for hydrogen production are

– From natural gas or bio-gas by reformingwith steam and/or oxygen

– From coal (or peat or wood or .....) by gasification– By electrolysis of water, using electricity from nuclear power or a

renewable source (wind, solar, ...)– Fermentative and other micro-organism systems

Separation of H2 from syngas (CO/H2/...) or other gas mixture canbe accomplished with for example pressure swing absorption (PSA) methods or membranesOften concentrated CO2 is a by-product → CO2 sequestration P

ictu

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Hydrogen liquefaction /1

The energy content per volumeof gaseous hydrogen is low; even in liquefied form it is less than that of for examplegasoline

Compression of H2 is veryenergy consuming; for examplecompression to 20 bar can cost10% of the heating value energy

Liquefaction requirestemperatures below 33 K (Tcrit), for atmosphericpressure 20 K.

For the Joule-Thomson effect a temperature < 200 K is needed

Sou

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Cooling of H2 is accomplished by multi-stage compression and expansion coupled with counter-flow heat exchange and energy recovery by expansion turbines, based on the Claude process: I. Compression to ~ 50 bar,

removal of compression heat II. Pre-cooling with liquid nitrogen

to ~ 80 K / ~ - 196°C III. Expanding and further cooling

of the H2 (80 → 30 K) IV. Expanding in a throttling valve

→ 20 K Liquid H2 is then stored at low

pressure and T ~ 20 K

Current energy requirements for H2 liquefaction are in the order of 30 – 60 MJ (8-17 kWh)/kg liquidH2 (theory : 14.1 MJ/kg) for a plant producing > 100 kg/h

(sources: BET04, IAEA99 ) Pic

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Simplified CRBJT cycleK-101 & E-100: compression and coolingLNG-101 and LNG-102: heat exchangeTEE-100: flow dividerQ-102: turbo-expanderVLV-100: throttling valveMIX-100: mixes gas from turbo-expanderand from flash separator

Work in the US under the DOE hydrogen program aims at liquefied H2 production at 13-18 MJ/kg, corresponding to ~ 0.5 US$/kg. The process is based on the

hydrogen Claude process, and is referred to as the CombinedReverse-Brayton Joule-Thomson (CRBJT) expansion cycle The efficiency of the hydrogen

Claude process may be improvedby using He, He/Ne or Ne insteadof H2 in the gas compression / expansion cycle (He-Brayton; Ne-Brayton cycle)


Also known as refrigerant R-702; Note: temperatures up to 100 K only

Sou

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H2 transport and storage /1

Hydrogen can be stored as a compressed gas, in liquefied form or as solid hydrides. For largeamounts, underground storage in aquifers and depleted oil/gas reservoirs can be considered. Metal hydride (MH) storage devices (as

developed by Ovonics) can store up to three times as much hydrogen in the same volume as can be stored using high pressure methods

Pic

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(≈ 340 bar)H2 storage as metal hydrides

High pressure H2 transport

Liquefied H2 transport


H2 transport and storage /2

Liquefied hydrogen pipeline (a few 100 m) at Cape Canaveral (FL); several 1000 km of pressurised H2pipeline exist worldwide

Pic

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An LH2 vessel

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LH2 storage at NASA



5.14 Dry ice

See also A11: chapter 6.8

Dry ice (solid CO2) production /1


belowtriple

point lineonlygas

+ solid

Picture: A11

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: http

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Throttlingof a

saturatedliquid:A B

Dry ice (solid CO2) production /2


Picture: A11

Here, heat rejection in condenserat 25°C to an NH3 v-c cycle


83/84

Sources #5 /1 A83: P.W. Atkins ”Physical chemistry”, 2nd ed., Oxford Univ. Press (1983) A11: R. C. Arora ”Refrigeration and air conditioning”, 2nd. Ed. PHI

Learning Private Limited, New Delhi (2011) Chapter 2.30, 6.8, 13.10-11, BET04: U Bossel, B. Eliasson, G. Taylor ”The future of the hydrogen economy:

bright or bleak?” (2003, 2004) http://www.oilcrash.com/articles/h2_eco.htm#nota_01

D03: İ. Dinçer “Refrigeration systems and applications” Wiley (2003)

F05: T.M. Flynn “Cryogenic engineering” 2nd Ed. Marcel Dekker (2005) IAEA99: “Hydrogen as an energy carrier and its production by nuclear power”

IAEA-TECDOC--1085 IAEA, Vienna (Austria) (1999) L11: S Lee et al., “The study on a new liquefaction cycle development for LNG

plant” Int. Gas Union Res. Conf. 2011 (15 p.) http://members.igu.org/IGU%20Events/igrc/igrc2011/igrc-2011-proceedings-and-presentations/poster-papers-session-4/P4-22_Sanggyu%20Lee.pdf/@@download/file/P4-22_Sanggyu%20Lee.pdf

For some p,h diagrams: http://www2.dupont.com/Refrigerants/en_US/products/literature.html (accessed Feb. 2016)http://christophe.lauverjat.pagesperso-orange.fr/mava/index.html (accessed Feb. 2016)


84/84

Sources #5 /2 ME06: S. Mokhatab, M.J. Economides, World Oil Magazine 227(2) (Feb

2006) http://www.worldoil.com/February-2006-Process-selection-is-critical-to-onshore-LNG-economics.html

MMVW14: S. Mokhatab, J.Y. Mak, J.V. Valappil, D.A. Wood, Handbook ofLiquefied Natural Gas, Elsevier / Gulf Profess. Publ. (2014) Chapter 1,(2),3,4 see https://abo.finna.fi/Record/alma.1238231 incl. E-bookWE09: X. Wang, M. Economides, ”Advanced natural gas engineering,” Gulf

Publ. Co. (2009) S90: A.L. Stolk ”Koudetechniek A1”, Delft Univ. of Technol. (1990) TV08: D,G. Thombare, S.K. Verma. ”Technological developments in the

Stirling cycle engines”, Renew. Sustain, Energy Rev. 12 (2008) 1-38Ö96: G. Öhman ”Kylteknik”, Åbo Akademi Univ. (1996)

http://users.abo.fi/rzevenho/Kylteknik%20_Ohman%2019962000.pdf

Kamerlingh Onnes Lab Leiden (1924)

Pic

ture

http

://w

ww

.eq.

uc.p

t/~ab

el/g

ifs/K

ol24

lg.J

PG

(F

eb. 2

017)

See also: Martinez, I. ”Lectures on Thermodynamics” – lecture 18 (English or Spanish) http://webserver.dmt.upm.es/~isidoro/bk3/index.htmlupdated and based on “Termodinámica básica y aplicada", Ed. Dossat, Madrid (1992) ISBN 84-237-0810-1

refrigeration (kylteknik) - Åbo akademiusers.abo.fi/rzevenho/ref17-oh5.pdf · reversed brayton...

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