Process Design for Cryogenics E-Book

Alexander Alekseev

• Herausgeber: Wiley-VCH
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 843

Veröffentlichungsjahr: 2024

Beschreibung

Up-to-date overview of the method for producing the main industrial gases

This book covers process design for cryogenic processes like air separation, natural gas liquefaction, and hydrogen and helium liquefaction. It offers an overview of the basics of cryogenics and information on process design for modern industrial plants. Throughout, the book helps readers visualize the theories of thermodynamics related to cryogenics in practice. A central concept in the book is the connection between the theoretical world of process design and the real limitations given by available hardware components and systems.

Sample topics covered in Process Design for Cryogenics include:

• Cryogenic gases like nitrogen, oxygen, argon, neon, hydrogen, helium, and methane
• Thermodynamics
• Typical cryogenic refrigeration processes, including the classic Joule Thomson process, the contemporary mixed-gas Joule Thomson process, and expander-based processes like Brayton and Claude cycles
• Helium and hydrogen liquefaction and air separation

Process Design for Cryogenics is a comprehensive must-have resource for engineers and scientists working in academia and industry on cryogenic processes.

Leseprobe

Table of Contents

Cover

Table of Contents

Title Page

Copyright

Dedication

Preface

Acknowledgments

Symbols, Signs, and Abbreviations

1 Introduction

1.1 Historical Background

1.2 Cryogenic Applications

References

2 Basics of Process Design

2.1 Design Procedure

2.2 Process Simulators and Fluid Properties

2.3 Optimization

2.4 Control Concept

References

3 Cryogenic Fluids

3.1 Air

3.2 Nitrogen

3.3 Oxygen

3.4 Argon

3.5 Methane

3.6 Neon

3.7 Hydrogen

3.8 Helium

3.9 Temperature–Enthalpy Diagram

3.10 Temperature–Entropy Diagram

References

4 Reversibility Concept

4.1 Reversibility and Irreversibility

4.2 Carnot Engine

4.3 Reversible Process as Benchmark

4.4 Entropy

4.5 Exergy Concept

4.6 Application of Exergy Concept for Thermodynamic Analysis, Exergy Loss

5 Unit Operations for Cryogenic Processes

5.1 Isenthalpic Expansion

5.2 Expansion in Expander

5.3 Heat Exchanger

5.4 Single Adiabatic Compression Stage

5.5 Multi-Stage Compression, Isothermal Compression

References

6 Key Hardware Components

6.1 Thermal Insulation/Coldbox

6.2 Heat Exchanger

6.3 Expanders

6.4 Expansion Valve

6.5 Compressors

References

7 Cryogenic Refrigeration

7.1 Principle of Cryogenic Refrigeration

7.2 Joule–Thomson Process (Nitrogen Joule–Thomson Process)

7.3 Brayton Process

7.4 Claude Process

7.5 Mixed-Fluid Joule–Thomson Process

7.6 Cryogenic Refrigeration Processes, Life Cycle

References

8 Liquefaction of Cryogenic Gases

8.1 Thermodynamic Basics for Liquefaction

8.2 Nitrogen Liquefaction

8.3 Helium Liquefaction

8.4 Natural Gas Liquefaction

References

9 Supplements

9.1 Supplements for Cryogenic Refrigeration

9.2 Supplements for Liquefaction

References

Index

End User License Agreement

List of Tables

Chapter 1

Table 1.2 Milestones in cryogenic engineering.

Table 1.1 Milestones in cryogenic + science.

Chapter 3

Table 3.1 Data properties for cryogenic gases, acc. to Ref. [1].

Table 3.2 Composition of dry air.

Table 3.3 Heat of ortho-to-para conversion, cumulative, according to Ref. [...

Table 3.4 Properties of helium isotopes.

Chapter 5

Table 5.1 Summary of terms around isenthalpic expansion.

Table 5.2 Comparing isenthalpic expansion to expansion in an expander.

Table 5.3 Impact of temperature difference in heat exchanger on exergy loss...

Table 5.4 Compression of air and helium.

Table 5.5 Comparison, adiabatic versus isothermal compression.

Chapter 6

Table 6.1 Typical characteristics of brazed aluminum plate-fin heat exchang...

Table 6.2 Spiral-wound heat exchanger for LNG applications.

Table 6.3 Examples of spiral-wound heat exchangers for LNG applications....

Table 6.4 Comparison of bearing systems.

Table 6.5 Constraints for pressure ratio, helium.

Table 6.6 Typical values/parameters for gas expanders.

Table 6.7 Comparison of bearing systems for cryogenic expanders (extension ...

Chapter 7

Table 7.1 Ordering of cryogenic refrigeration processes according to pressu...

Table 7.2 Minimum power requirement for typical temperature levels,

T

amb

 = ...

Table 7.3 Definitions of some distinguishing process states.

Table 7.4 Typical cooling temperature ranges as well as pressures ranges.

Table 7.5 Basis of design.

Table 7.6 Input process data derived from the hardware concept.

Table 7.7 Input data known from previous calculations.

Table 7.8 Output process data, nitrogen Joule–Thomson process,

T

o

 = 100 K....

Table 7.9 Heat exchanger data, nitrogen-Joule–Thomson-process,

T

o

 = 100 K....

Table 7.10 Joule–Thomson expansion.

Table 7.11 Compressor specification, nitrogen Joule–Thomson-process,

T

o

 = 1...

Table 7.12 Performance of the designed nitrogen Joule–Thomson process,

T

o

 =...

Table 7.13 Exergy losses in process units of nitrogen Joule–Thomson-process...

Table 7.14 Impact of temperature difference in heat exchanger on exergy los...

Table 7.15 Process data for helium Brayton process derived from the process...

Table 7.16 Further assumptions for process calculations.

Table 7.17 Process data, helium Brayton process,

T

o

= 80 K.

Table 7.18 Heat exchanger, helium Brayton process,

T

o

= 80 K.

Table 7.19 Compressor specification, helium Brayton process,

T

o

= 80 K.

Table 7.20 Expander specification, helium Brayton process,

T

o

= 80 K.

Table 7.21 Performance of the helium Brayton process,

T

o

= 80 K.

Table 7.22 Exergy loss, helium Brayton process,

T

o

= 80 K.

Table 7.23 Impact of temperature difference in heat exchanger on exergy los...

Table 7.24 Input data for nitrogen Claude process derived from the hardware...

Table 7.25 Output process data, nitrogen Claude process,

T

o

= 100 K.

Table 7.26 Heat exchanger data, nitrogen Claude process.

Table 7.27 Compressor specification, nitrogen Claude process,

T

o

= 100 K.

Table 7.28 Expander specification.

Table 7.29 Joule–Thomson expansion.

Table 7.30 Performance of the nitrogen Claude process.

Table 7.31 Exergy loss, nitrogen Claude process.

Table 7.32 Impact of temperature difference in heat exchanger on exergy los...

Table 7.33 Input data for process calculation, helium Claude process,

T

o

 = ...

Table 7.34 Further Input data for process calculation, helium Claude proces...

Table 7.35 Output process data, helium Claude process,

T

o

= 4.6 K.

Table 7.36 Heat exchanger data, helium Claude process.

Table 7.37 Compressor specification for helium Claude process.

Table 7.38 Expander specification for helium Claude process.

Table 7.39 Joule–Thomson expansion in helium Claude process.

Table 7.40 Performance of the helium Claude process.

Table 7.41 Helium Claude process.

Table 7.42 Impact of temperature difference in heat exchangers on specific ...

Table 7.43 Exergy efficiency of single heat exchangers.

Table 7.44 Example of allocation of parasitic heat to heat exchangers.

Table 7.45 Hydrocarbons, boiling point, triple point.

Table 7.46 Example of mixed fluid refrigerant composition.

Table 7.47 Binary interaction parameters for Soave–Redlich–Kwong equation o...

Table 7.48 Change of phase compositions during the isenthalpic expansion pr...

Table 7.49 Difference between the mixed-fluid Joule–Thomson process and the ...

Table 7.50 Input process data derived from the hardware concept.

Table 7.51 Further assumptions for process calculations.

Table 7.52 Output process data, mixed-fluid Joule–Thomson process,

T

o

 = 100...

Table 7.53 Heat exchanger data, mixed-fluid Joule–Thomson process,

T

o

 = 100...

Table 7.56 Performance of the designed mixed-fluid Joule–Thomson process,

T

o

Table 7.57 Exergy losses in process units of mixed-fluid Joule–Thomson-proce...

Table 7.58 Impact of temperature difference in heat exchanger on exergy los...

Table 7.59 Adjustment of mixed-fluid composition.

Table 7.60 Parameters for processes with mixed fluids “mix 1” and “mix 2.”...

Table 7.61 Mixed-fluid compositions, mix 3.

Table 7.62 Phenomena in the heat exchanger for mixed-fluid Joule–Thomson pro...

Table 7.54 Joule–Thomson expansion.

Table 7.55 Compressor specification, mixed Joule–Thomson-process,

T

o

 = 100 ...

Chapter 8

Table 8.1 Minimum liquefaction work for cryogenic g...

Table 8.2 Process design approaches for liquefaction purposes.

Table 8.3 Common process design options for flash-gas management.

Table 8.4 Min liquefaction work for nitrogen, depending on feed gas pressur...

Table 8.5 Performance specification, ELM 9000.

Table 8.6 Typical applications for helium plants.

Table 8.7 Performance of a laboratory helium liquefier L70 at temperature <...

Table 8.8 Performance of helium liquefier Helial, Air Liquide (https://adva...

Table 8.9 Natural gas composition, in mol%.

Table 8.10 Minimum liquefaction work for CH

4

, depending on feed gas pressur...

Table 8.11 Heat exchanger data, mixed-fluid-based process for liquefaction ...

Table 8.12 Composition of fluids at inlet and outlets of phase separator.

Table 8.13 Heat exchanger data, mixed-fluid-based process for liquefaction ...

Chapter 9

Table 9.1 Cost comparison for a Joule–Thomson system based on different com...

Table 9.2 Cost comparison for a Joule–Thomson system based on different com...

Table 9.3 Specifications for feed gas, product, and cooling water.

Table 9.4 Specifications for rotating machinery.

Table 9.5 Selected parameters for process simulation (assumed).

Table 9.6 Process data for nitrogen liquefaction process based on dual expa...

Table 9.7 Heat exchanger data.

Table 9.8 Process data: recycle compressor.

Table 9.9 Process data, expander-booster units.

Table 9.10 Evaluation, overall process.

Table 9.11 Losses.

Table 9.12 Input data for process calculation: helium liquefaction process ...

Table 9.13 Output process data: helium liquefier.

Table 9.14 Heat exchanger data: helium Claude process.

Table 9.15 Compressor specification: helium liquefier.

Table 9.16 Expander specification: helium liquefier.

Table 9.17 Joule–Thomson expansion in helium Claude process.

Table 9.18 Power demand for nitrogen liquefaction.

Table 9.19 Performance estimation for helium liquefaction process.

Table 9.20 Losses in helium liquefaction process.

Table 9.21 Specifications for feed gas, product, and cooling water.

Table 9.22 Process design data, mixed fluid cycle.

Table 9.23 Composition of mixed fluid.

Table 9.24 Binary interaction parameters.

Table 9.25 Simulation results: process data/parameters.

Table 9.26 Heat exchanger data for mixed-fluid Joule–Thomson process for na...

Table 9.27 Compressor-specification, basic mixed fluid Joule–Thomson proces...

Table 9.28 Performance, basic mixed fluid Joule–Thomson process for natural...

Table 9.29 Losses, basic mixed-fluid Joule–Thomson process for natural gas ...

Table 9.30 Composition of mixed fluid for processing with a single-phase se...

Table 9.31 Simulation results: process data/parameters.

Table 9.32 Composition of fluids.

Table 9.33 Heat exchanger data: mixed fluid process with single-phase separ...

Table 9.34 Compressor specification: mixed fluid process with single-phase ...

Table 9.35 Process performance: mixed-fluid process with single-phase separ...

Table 9.36 Losses in mixed-fluid process with single-phase separator.

List of Illustrations

Chapter 1

Figure 1.1 Refrigeration technology.

Figure 1.2 Cryogenics as utility.

Chapter 2

Figure 2.1 Process design, typical procedure.

Chapter 3

Figure 3.1 Cryogenic fluids, sorted by source.

Figure 3.2 Ortho-hydrogen (left) and para-hydrogen (right).

Figure 3.3 Para-hydrogen fraction in equilibrium hydrogen, depending on temp...

Figure 3.4 Heat of ortho-to-para conversion, cumulative, according to Ref. [...

Figure 3.6 Phase diagram of

4

He.

Figure 3.5 Specific heat of ortho-to-para conversion.

Figure 3.8 Temperature–enthalpy diagram for nitrogen.

Figure 3.7 Lambda curve of

4

He.

Figure 3.9 temperature–entropy diagram for nitrogen.

Figure 3.10 temperature–entropy diagram for some cryogenic fluids.

Chapter 4

Figure 4.1 Carnot engine, main functionalities.

Chapter 5

Figure 5.1 Isenthalpic expansion of a high-pressure gas.

Figure 5.2 Energy conservation law for expansion in a valve.

Figure 5.3 Cryogenic valve, made by WEKA.

Figure 5.4 Isenthalpic expansion in the temperature–enthalpy diagram (nitrog...

Figure 5.5 Isenthalpic expansion in the temperature–entropy diagram (nitroge...

Figure 5.6 Temperature–entropy diagram for helium above 220 K, the 200 bar-i...

Figure 5.7 Temperature–entropy diagram for helium below 14 K (two-phase area...

Figure 5.8 Exergy balance for a valve.

Figure 5.9 Turboexpander for an air separation plant: 1-expander casing, 2- ...

Figure 5.10 Expansion in an expander, energy conservation law.

Figure 5.11 Expansion in an expander in

T,s

-diagram.

Figure 5.12 Exergy balance for an expander.

Figure 5.13 Loading devices for turboexpander (a) oil-brake, (b) electrical ...

Figure 5.14 Expansion processes in temperature–entropy diagram, s in kJ/(kg ...

Figure 5.15 (a) Double-tube heat exchanger, (b) cross-section of double tube...

Figure 5.16 Heat exchanger with two material streams.

Figure 5.17 Heat exchanger divided in virtual zones.

Figure 5.18 Heat exchanger with four material flows (left) and equivalent he...

Figure 5.19 Balances for heat exchanger with two material flows (a) energy c...

Figure 5.20 Adiabatic compression stage.

Figure 5.21 Adiabatic compression in

T,s

-diagram, 1 → 2 – reversible (isentr...

Figure 5.22 Exergy balance for single adiabatic compressor stage.

Figure 5.23 Symbol used in process flow diagrams for a multi-stage compresso...

Figure 5.24 Four-stage centrifugal compressor,

p

1

< p

2

< p

Figure 5.25 Example of a four-stage main air compressor with integrated cond...

Figure 5.26 Four-stage compression in

T,s

-diagram.

Figure 5.27 Four-stage compression in

T,s

-diagram, if the states at the inle...

Figure 5.28 Isothermal compression in

T,s

-diagram.

Figure 5.29 Exergy balance for multi-stage compressor.

Chapter 6

Figure 6.1 Heat inleak into the coldbox.

Figure 6.2 An example of multilayer insulation based on the combination of a...

Figure 6.3 Design of vessel for storage of cryogenic liquid.

Figure 6.4 Neck tube connection, schematically.

Figure 6.5 Aluminum plate-fin heat exchanger, 1 – Core, 2 – Header, 3 – Nozz...

Figure 6.6 Aluminum plate-fin heat exchanger, 4 – Width, 5 – Height, 6 – Len...

Figure 6.7 Typical fin designs.

Figure 6.8 Manufacturing of aluminum plate-fin heat exchangers.

Figure 6.9 Spiral-wound heat exchanger, mechanical design.

Figure 6.10 Spiral-wound heat exchanger, tube plate end.

Figure 6.11 Spiral-wound heat exchanger, manufacturing of tube bundle acc to...

Figure 6.12 Fabrication of SWHE, mandrel (operation 1.1 according...

Figure 6.13 Fabrication of SWHE, tube winding with 4 tubes in par...

Figure 6.14 Fabrication of SWHE, tube winding complete (operation 2.5 accord...

Figure 6.15 Spiral-wound heat exchanger, manufacturing procedure according t...

Figure 6.16 Fabrication of SWHE, heat exchanger complete (operation 3.3 acco...

Figure 6.17 Expander impeller and inlet nozzles.

Figure 6.18 Hero’s engine.

Figure 6.19 Typical efficiency curve for a centrifugal expander.

Figure 6.20 Classification of bearings for centrifugal expander.

Figure 6.21 Expander-booster unit.

Figure 6.22 Impeller designs for expander.

Figure 6.23 Labyrinth seal, principle.

Figure 6.24 Combination of labyrinth seal and seal gas.

Figure 6.25 Adjustable inlet guide vanes without expander wheel.

Figure 6.26 Helium expander, overall design.

Figure 6.27 Rotor cartridge of a helium expander, expander wheel on the righ...

Figure 6.28 Bearing concepts for helium expander (a) oil bearings, (b) stati...

Figure 6.29 Principle of gas brake.

Figure 6.30 Expansion of supercritical liquid by means of (a) expansion valv...

Figure 6.31 T,s diagram of expansion in a Joule–Thomson expander: the dashed...

Figure 6.32 Operation ranges for three compressor types.

Figure 6.33 Energy conversion and transformation steps in a centrifugal comp...

Figure 6.34 Stage of a radial compressor.

Figure 6.35 Impeller and diffuser of a radial compressor

Figure 6.36 Pressure, temperature, and velocity profiles in an adiabatic com...

Figure 6.37 Options for compressor wheel design.

Figure 6.38 Integrally geared compressor, MAN Energy Solution.

Figure 6.39 Single-shaft centrifugal compressor, four-stage (as an air compr...

Figure 6.40 Pressure ratio in a single compression stage depending on impell...

Figure 6.41 Performance map of a centrifugal compressor.

Figure 6.42 Inlet guide vanes, left: closed, right: open. Source: Matthew Os...

Figure 6.43 Helical screws of a screw compressor. Source: Ingersoll Rand.

Figure 6.44 Screw compressor, principle of compression. Source: unknown

Figure 6.45 Screw compressor, functions of compressor oil.

Figure 6.46 Reciprocating compressor, main elements.

Figure 6.47 Reciprocating compressor, working cycle.

Figure 6.48 Reciprocating compressor, impact of valves on indicator diagram....

Figure 6.49 Reciprocating compressor, impact of isentropic exponent on indic...

Figure 6.50 Compressor efficiency versus compression ratio for hydrogen and ...

Figure 6.51 Process compressor, copyright Burckhardt Compression.

Figure 6.52 High-pressure dry compressor, copyright Burckhardt Compression....

Figure 6.53 Cylinder with adjustable clearance pocket, principle.

Chapter 7

Figure 7.1 Overview, cryogenic refrigeration processes.

Figure 7.2 Refrigerator idea: cold surface (of a refrigerator) absorbs heat ...

Figure 7.3 Energy conservation law for refrigerator.

Figure 7.4 Home refrigerator (GL-B201SLLB), Source: LG.

Figure 7.5 Refrigerator-pump analogy.

Figure 7.6 Energy conservation law for refrigerator with parasitic heat flow...

Figure 7.7 Joule–Thomson process, basic process flow diagram; left- thermal ...

Figure 7.8 Copper tube as evaporator.

Figure 7.9 Joule–Thomson refrigerator, (a) basic process flow diagram, (b) “...

Figure 7.10 Cool-down procedure of a Joule–Thomson refrigerator.

Figure 7.11 Joule–Thomson process, system boundary.

Figure 7.12 Warm end of heat exchanger in

T,s

-diagram.

Figure 7.13 Joule–Thomson refrigerator with bath evaporator.

Figure 7.14 Nitrogen-Joule–Thomson-process in

T,s

-diagram.

Figure 7.15

T,Q

-diagram, heat exchanger.

Figure 7.16 Temperature difference profile (ΔT,Q-diagram) in heat exchanger...

Figure 7.17

T,Q

-diagram, evaporator, nitrogen Joule–Thomson process,

T

o

 = 10...

Figure 7.18 Distribution of exergy losses in given nitrogen Joule–Thomson-pr...

Figure 7.19 Joule–Thomson expansion in

T,s

-diagram.

Figure 7.20 a) Typical isobars in the gaseous area of

T,h

-diagram, b) conseq...

Figure 7.21 Coefficient of performance of a nitrogen-Joule–Thomson process, ...

Figure 7.22 Q/MTD value for heat exchanger.

Figure 7.23 Flowrate control options: a) by means of control valve, b) by me...

Figure 7.24 Control of refrigerant amount circulated.

Figure 7.25 Brayton process, basic process flow diagram; left - thermal insu...

Figure 7.26 Brayton process, system boundary for cold part.

Figure 7.27 Concept of helium Brayton refrigerator.

Figure 7.28 Helium Brayton process in

T,s

-diagram.

Figure 7.29

T,Q

-diagram, heat exchanger, helium Brayton process.

Figure 7.30 Temperature difference in heat exchanger (Δ

T,Q

- diagram), ...

Figure 7.31

T,Q

-diagram, cold has heat exchanger, helium Brayton process.

Figure 7.32 Exergy losses in the helium Brayton process.

Figure 7.33 Isothermization approach (a) single expander-cold gas heat excha...

Figure 7.34 Coefficient of performance of a helium Brayton pro...

Figure 7.35 Q/MTD of the main heat exchanger, helium Brayton process

dTwe

 = ...

Figure 7.36 Basic Claude process, process flow diagram. Left - the thermal i...

Figure 7.37 Claude process, system boundary for cold part.

Figure 7.38 Nitrogen Claude process. Left - the thermal insulation is shown,...

Figure 7.39 Nitrogen Claude process in

T,s

-diagram.

Figure 7.40 Concept of the nitrogen Claude process.

Figure 7.41

T,Q

-diagram, heat exchanger HEX3.

Figure 7.42

T,Q

-diagram, heat exchanger HEX2.

Figure 7.43

T,Q

-diagram for both heat exchangers HEX2 and HEX3 together.

Figure 7.44 Temperature difference profile (Δ

T,Q

...

Figure 7.45

T,Q

-diagram for evaporator.

Figure 7.46 Exergy loss in the nitrogen Claud process.

Figure 7.47 Helium Claude process with two turboexpanders (a) simplified vie...

Figure 7.48 Helium Claude process, typical staging.

Figure 7.49 Helium Claude process, PFD for process calculation.

Figure 7.50 Helium Claude process in

T,s

-diagram.

Figure 7.51 Combined

T,Q

-diagram and Δ

T,Q

...

Figure 7.52 Combined

T,Q

-diagram and combined Δ...

Figure 7.53

T,Q

-diagram for evaporator.

Figure 7.54 Distribution of losses in helium Claude process.

Figure 7.55 Distribution of heat exchanger losses in helium Claude process....

Figure 7.56 Joule–Thomson process, basic process flow diagram left: with the...

Figure 7.57

T,s

-diagram for a typical nitrogen–hydrocarbon mixture.

Figure 7.58

T,s

-diagram for a typical nitrogen–hydrocarbon mixture (three-ph...

Figure 7.59 Mineral oil–water mixture as a liquid–liquid (LL) fluid system....

Figure 7.60 Typical isobars pattern left – nitrogen; right – mixture in two-...

Figure 7.61

T,h

-diagram for a typical nitrogen–hydrocarbon mixture.

Figure 7.62

T,h

-diagram for a typical nitrogen–hydrocarbon mixture (three-ph...

Figure 7.63 Composition and fractions of vapor phase, liquid phase, and liqu...

Figure 7.64 Distribution of mixed-fluid components between the phases

VF·y

...

Figure 7.65 Intensity of phase transition, vapor phase.

Figure 7.66 Comparison:

T,h

-diagram for a typical nitrogen–hydrocarbon mixtu...

Figure 7.67 Difference between the specific enthalpy at 300 K and 1 bar and ...

Figure 7.68 Typical mixed-fluid Joule–Thomson process in

T,h

-diagram, HP-hig...

Figure 7.69 Typical mixed-fluid Joule–Thomson process in

T,h

-diagram, cold e...

Figure 7.70 Typical mixed-fluid Joule–Thomson process in

T,h

-diagram, warm e...

Figure 7.71

T,Q

-profile in the heat exchanger.

Figure 7.72 Temperature difference profile (Δ

T,Q

-diagram) in heat exchanger...

Figure 7.73 Mixed-fluid Joule–Thomson process, system boundary: a) for the w...

Figure 7.74 Mixed-fluid Joule–Thomson refrigerator for process calculations....

Figure 7.75 Temperatures in the evaporator, mixed Joule–Thomson process,

T

o

 ...

Figure 7.76 Distribution of losses, mixed-fluid Joule–Thomson process,

T

o

 = ...

Figure 7.77

T,q

-diagrams and temperature difference profiles for two mixed f...

Figure 7.78 Process in

T,h

-diagram for two mixed fluids,...

Figure 7.79 Temperature difference profiles for two mixed fluids,

p

HP

 = 20 b...

Figure 7.80 Liquidus-line (solidification) for methane–propane mixture accor...

Figure 7.81 Overview, compressor for mixed-fluid Joule–Thomson process.

Chapter 8

Figure 8.1 T,s-diagram of isobaric nitrogen liquefaction.

Figure 8.2 Liquefier from external perspective.

Figure 8.3 Scheme for calculating the minimum liquefaction work...

Figure 8.4 Joule–Thomson processes for liquefaction purposes: (a) Nitrogen J...

Figure 8.5 Basic Claude process for nitrogen liquefier, GAN – gaseous nitrog...

Figure 8.6 Dual-expander nitrogen Claude liquefier.

Figure 8.7 Helium Claude liquefier with liquid nitrogen precooling.

Figure 8.8 Classification of the liquefaction processes.

Figure 8.9 Principle of liquefaction process with external cooling.

Figure 8.10 Example of a liquefaction process with external cooling, derived...

Figure 8.11 General setup for stand-alone nitrogen liquefier.

Figure 8.12 Modifications of the dual-expander nitrogen Claude liquefaction ...

Figure 8.13 Core process for nitrogen liquefaction.

Figure 8.14 Expansion of the nitrogen liquefaction process, subcooling by fl...

Figure 8.15 Process design for the LIN-extension.

Figure 8.16 Integration of the feed compressor into the core liquefaction pr...

Figure 8.17 Example of temperature profile in the heat exchanger of a dual-e...

Figure 8.18 Example of loss distribution in a dual-expander Claude process f...

Figure 8.19 Nitrogen liquefier, Cosmodyne.

Figure 8.20 Process diagram of Cosmodyne process, as shown in manufacturer’s...

Figure 8.21 Combination of air separation unit and nitrogen liquefier for pr...

Figure 8.22 Laboratory liquefier with some infrastructure, copyright Linde p...

Figure 8.23 Overall setup for a helium liquefier.

Figure 8.24 Core process for helium liquefier.

Figure 8.25 Example of a process with pre-cooling by means of liquid nitroge...

Figure 8.26 Example of a process with pre-cooling by means of liquid nitroge...

Figure 8.27 Supply of liquid nitrogen to helium liquefier by means of LIN tr...

Figure 8.28 Purifier for final purification of helium gas, copyright Linde K...

Figure 8.29 Core process section of a laboratory helium liquefier, copyright...

Figure 8.30 Cold box of a laboratory helium liquefier.

Figure 8.31 Cold box of a laboratory helium liquefier from external perspect...

Figure 8.32 Cold box of a large helium liquefier, the vacuum vessel is remov...

Figure 8.33 Natural gas liquefaction, overall process chain.

Figure 8.36 Principle of natural gas liquefaction by means of an external co...

Figure 8.34 Natural gas liquefier, feed, and products.

Figure 8.35 Natural gas liquefier with integrated fractionation, feed, and p...

Figure 8.37 Principle of natural gas liquefaction via external cooling proce...

Figure 8.38 Temperature profile (T,Q-diagram) in heat exchanger.

Figure 8.39 System boundary for the entire cold part of natural gas liquefac...

Figure 8.40 “Moving” system boundary for natural gas liquefaction process ba...

Figure 8.43 Application of phase separator for distribution of two-phase flo...

Figure 8.41 (a) typical isobar pattern for nitrogen–hydrocarbon mixture in t...

Figure 8.44 Mixed-fluid Joule–Thomson process with single phase-separator fo...

Figure 8.42 Flow-patterns in a two-phase flow, vertical channels (https://ww...

Figure 8.45 T,-Q-diagram for heat exchanger (mixed-fluid JT process with sin...

Figure 8.46 Mixed-fluid Joule–Thomson Process with precooling stage, new sys...

Figure 8.47 (a) upper part of mixed-fluid Joule–Thomson Process with precool...

Figure 8.50 LNG Air Products C3MR process presented in conventional manner....

Figure 8.48 Mixed-fluid Joule–Thomson Process with precooling stage, new sys...

Figure 8.51 Smartfin© process.

Figure 8.49 LNG Air Products C3MR process [16].

Figure 8.52 Smartfin© process, presented in conventional manner.

Chapter 9

Figure 9.1 Joule–Thomson refrigerator with an intermediate pressure.

Figure 9.2 Joule–Thomson refrigerator with external precooling stage.

Figure 9.3 Original Claude process for air liquefaction. C – compressor, A –...

Figure 9.4 Original Claude process for air liquefaction AIR – ambient air, L...

Figure 9.5 Kapitsa process for air liquefaction, original version according ...

Figure 9.6 Kapitsa process for air liquefaction, AIR – ambient air, LAIR – l...

Figure 9.7 Temperature profile and temperature difference profile, both depe...

Figure 9.8 Losses in a process for nitrogen liquefaction.

Figure 9.9 Helium liquefier with liquid nitrogen precooling.

Figure 9.10 Combined T, Q diagram (temperature profile) for all heat exchang...

Figure 9.11 Combined ΔT, Q diagram (temperature difference...

Figure 9.12 Distribution of losses in helium liquefaction process.

Figure 9.13 Distribution of losses in heat exchangers.

Figure 9.14 Basic mixed fluid-Joule–Thomson process for natural gas liquefac...

Figure 9.15 Overall temperature profile (T,Q diagram) in heat exchanger.

Figure 9.16 Temperature difference in heat exchanger (ΔT, Q diagram).

Figure 9.17 Warm composite stream as a composition of mixed fluid stream 1a ...

Figure 9.18 Temperature profile (T,Q diagram) for mixed-fluid cycle (without...

Figure 9.19 Loss distribution, mixed fluid Joule–Thomson process for natural...

Figure 9.20 Mixed fluid process with single phase-separator.

Figure 9.21 Temperature profile (T, Q diagram) in heat exchanger.

Figure 9.22 Temperature difference in heat exchangers (ΔT,Q diagram).

Figure 9.23 Loss distribution, mixed fluid process with single-phase separat...

Figure 9.24 Principle of mixed-fluid Joule–Thomson process with two-phase se...

Guide

Cover

Table of Contents

Title Page

Copyright

Dedication

Preface

Acknowledgments

Symbols, Signs, and Abbreviations

Begin Reading

Index

End User License Agreement

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Process Design for Cryogenics

Alexander Alekseev

Author

Dr.-Ing. Alexander Alekseev

Linde GroupDr.-Carl-von-Linde-Str. 6HöllriegelskreuthGermany, 82049

Cover Image: © Carter Hurd/Shutterstock

All books published by WILEY-VCH are carefully produced. Nevertheless, authors, editors, and publisher do not warrant the information contained in these books, including this book, to be free of errors. Readers are advised to keep in mind that statements, data, illustrations, procedural details or other items may inadvertently be inaccurate.

Library of Congress Card No.: applied for

British Library Cataloguing-in-Publication DataA catalogue record for this book is available from the British Library.

Bibliographic information published by the Deutsche NationalbibliothekThe Deutsche Nationalbibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data are available on the Internet at <http://dnb.d-nb.de>.

© 2024 WILEY-VCH GmbH, Boschstr. 12, 69469 Weinheim, Germany

All rights reserved including rights for text and data mining and training of artificial technologies or similar technologies (including those of translation into other languages). No part of this book may be reproduced in any form – by photoprinting, microfilm, or any other means – nor transmitted or translated into a machine language without written permission from the publishers. Registered names, trademarks, etc. used in this book, even when not specifically marked as such, are not to be considered unprotected by law.

Print ISBN: 978-3-527-34422-2

ePDF ISBN: 978-3-527-81560-9

ePub ISBN: 978-3-527-81562-3

oBook ISBN: 978-3-527-81563-0

To my wife Ekaterina, for her love and encouragement in keeping me healthy. She never ceased to convince me that the life beyond cryogenics is lovely, a notion she is absolutely correct about.

Preface

This book is an outgrowth of courses in “Cryogenics and Industrial Cryogenic Plants” taught at the Technical University of Munich over the past 12 years. This course emphasizes process design and simulation of cryogenic processes. Consequently, the book specifically addresses topics and aspects related to process design, rather than covering cryogenic matter in its entirety. This relatively narrow specialization of the book reflects the increasing professional differentiation within the engineering community. This trend is also observable in the technical literature about cryogenics: there are books tailored for physicists by physicists (such as [1–3]), for mechanical engineers by mechanical engineers (such as [4–8]), and for material property experts by their counterparts. However, there is a scarcity of literature on low-temperature technology specifically tailored for chemical engineers by process engineers, with only Isalski’s book from 1989 being mentioned. With this book, I endeavor to bridge this gap.

The main features of this book are as follows:

Focus on Four Basic Processes:

This book exclusively focuses on four fundamental cryogenic processes: Joule–Thomson process, mixed fluid Joule–Thomson process, Brayton process, and Claude process. The decision to limit the study material to these four processes was made deliberately.

These four processes are comprehensively examined in Chapter 7 about cryogenic refrigeration. They are then revisited within the context of their application in Chapter 8 about liquefaction processes. The approach and methodology employed are universally applicable and can be extended to all other cryogenic and non-cryogenic processes.

Process Examples:

The book includes several examples of process calculations that illustrate the typical relationships.

Thermodynamics:

Approximately one-quarter of the book (Chapters 4 and 5) is devoted to thermodynamic fundamentals. While these concepts are commonly covered in other texts, I have meticulously curated the most essential and valuable content to optimize its application in process analysis, particularly in Chapters 7, 8, and 9.

Hardware Components:

The detailed design (sizing/dimensioning) of key hardware components (compressors, expanders, heat exchangers, etc.) is not extensively covered in this book. But since these hardware components play a pivotal role in determining process design, they are briefly outlined in Chapter 6 to provide an overview.

The book contains some sections addressing specific aspects or topics, which possess a broad applicability across all cryogenic processes (such as the drawbacks of subatmospheric operating conditions or methods for comparing two processes). However, these text blocks are embedded in chapters for individual basic processes, where they fit best in terms of content. Creating a separate chapter for it would lead to a complicated structure of the book. I expect that the attentive reader will recognize and correctly assign these contents.

Not covered within the scope of the book are cascade processes (as well as cascading as a process design method), processes based on regenerators as heat exchange device, and electromagnetic (electrocaloric, magnetocaloric, or optical) methods. Topics such as the thermodynamic description of material properties (equations of state, etc.), measurement technology, and instrumentation are also not addressed in this book; there are many good books available on these subjects.

The time constraints and other limitations imposed by my full-time professional commitments may have led to the text not being as polished as I would have liked. However, I am eager to move forward and publish the book in its current state. I welcome feedback, corrections, and suggestions for improvement. Please send them directly to me.

References

1

Pobell, F. (2007).

Matter and Methods at Low Temperatures

. Berlin, Heidelberg: Springer-Verlag. ISBN: 978-3-540-46356-6; eBook ISBN: 978-3-540-46360-3.

https://doi.org/10.1007/978-3-540-46360-3

.

2

Ventura, G. and Risegari, L. (2010).

The Art of Cryogenics: Low-Temperature Experimental Techniques

. Elsevier.

3

Van Sciver, S.W. (2012).

Helium Cryogenics

, 470. New York: Springer Science.

http://dx.doi.org/10.1007/978-1-4419-9979-5

.

4

Jungnickel, H., Agsten, R., and Kraus, W.E. (1990).

Grundlagen der Kältetechnik

. Berlin: Verlag Technik GmbH.

5

Flynn, T.M. (1997).

Cryogenic Engineering

. CRC Press.

6

Barron, R.F. (1985).

Cryogenic Systems

. Monographs on Cryogenics.

7

Timmerhaus, K.D. and Flynn, T.M. (2013).

Cryogenic Process Engineering

. New York: Springer. ISBN: 978-1-4684-8758-9; eBook ISBN: 978-1-4684-8756-5.

https://doi.org/10.1007/978-1-4684-8756-5

.

8

Hausen, H. and Linde, H. (1985).

Tieftemperaturtechnik

. Berlin, Heidelberg, New York, Tokyo: Springer Verlag.

Acknowledgments

I learned to apply the exergy concept as a tool for thermodynamic analysis from Prof. Viktor Brodianski in Moscow, where Vladimir Mogorychny also made significant contributions to my development.

During my doctoral studies at the Dresden University of Technology, I gleaned the fundamental principles of process engineering from Prof. Hans Quack. Our most engaging conversations often occurred on the way to lunch in the cafeteria. I am confident he will recognize his foundational ideas and arguments, and I hope he finds satisfaction in their application.

Later, I started to work as a process engineer at Linde AG, where I benefited immensely from the expertise of Horst Corduan and Dr. Dirk Schwenk. Furthermore, my initial department head, Gerhard Pompl, provided steadfast support for all my process engineering investigations. Six additional names from the Linde Group deserve special mention – Prof. Hans Kistenmacher, Prof. Aldo Belloni, Dr. Andreas Opfermann, Dr. Harald Ranke, Dr. Krish Krishnamurthy, and Prof. Harald Klein, who is now Chair of the Department for Plant and Process Technology at the Technical University of Munich. These colleagues have been instrumental in supporting and inspiring me to establish the lecture “Cryogenics and Industrial Cryogenic Plants" at the Technical University of Munich, which serves as the foundation for the content of this book. In addition, I am grateful for the unwavering support provided by the current management, Dr. Amitabh Gupta and Dr. Minish Shah. My heartfelt thanks go out to all the aforementioned personalities.

I express my most sincere appreciation to several people who contributed to the success of this project: Dr. Wolfgang Eberhard Kraus reviewed and provided feedback on the contents of the first five chapters. While I was unable to address all his comments, I am immensely grateful to him for his efforts. Paul Glatt and Elisabeth Mae Wilbur have corrected my English and contributed to making the text more comprehensible. Many thanks to the doctoral students who helped me with lectures: Johanna Hemaurer, Marc Xia, Umberto Cardella, Christian Wolf, and Chengyuan Wu, to Senior Engineer Sebastian Rehfeldt, and Secretary Melanie Laubenbacher, as well as to the students who prepared the German version of the book: Martin Kibili, Manuel Mayr, Alexander Vogt, Sebastian Obermeier, Patrick Brandl, Lola Mercier, Ahmed Elkhoshet, Giovanni Turi da Fonte Dias, Mauricio Platteau, and Philipp Schwab.

Symbols, Signs, and Abbreviations

Latin Symbols

Symbol

Description

Example of units

COP

coefficient of performance

C

p

heat capacity at constant pressure

J/K

c

p

mass [or molar] specific heat capacity at constant pressure

J/(kg K)J/(mol K)

C

v

heat capacity at constant volume

J/KJ/K

c

v

mass [or molar] specific heat capacity at constant volume

J/(kg K)J/(mol K)

D

exergy loss

J, kWh

Ḋ

exergy loss flow

W, kW

E

exergy

J

Ė

exergy flow

W

e

mass [or molar] specific exergy

J/kgJ/mol

H

enthalpy

J, kWh

Ḣ

enthalpy flow

W, kW

h

mass [or molar] specific enthalpy

J/kgJ/mol

h

b

mass [or molar] specific enthalpy at the boiling point

J/kgJ/mol

h

d

mass [or molar] specific enthalpy at the dew point

J/kgJ/mol

m

mass

kg

ṁ

mass flow or mass flowrate

kg/s

M

or

M

r

molecular weight

g/mol

MTD

mean temperature difference in heat exchanger

K

LTD

logarithmic temperature difference in heat exchanger

K

LF

liquid fraction = molar [or mass] fraction of liquid in a two-phase fluid/material stream

N

molar amount of substance

mol

Ṅ

molar flow or molar flowrate

mol/sNm

3

/h

p

pressure

bar

p

s

boiling pressure or saturation pressure or vapor pressure

bar

P

power as mechanical or electric power

W, kW

P

EXP

mechanical power generated by an expander

W, kW

P

COMP

mechanical power required for driving a compressor

W, kW

Q

heat

J, kWh

heat flow

W, kW

o

cooling capacity (or cooling power) of a refrigerator

W, kW

amb

waste heat rejected into environment/ambient (to cooling air or cooling water)

W, kW

heat flow, transferred from warm side/fluid to cold side/fluid in a heat exchanger = heat exchanger duty

W, kW

is

heat flow through non-ideal thermal insulation

W, kW

q

mass [or molar] specific heat

J/kg

mass [or molar] specific heat flow

W/kg

R

m

universal gas constant

R

= 8.314 J/(mol K)

J/(mol K)

S

entropy

J/K

entropy flow

W/K

s

mass [or molar] specific entropy

J/(kg K)J/(mol K)

s

b

mass [or molar] specific entropy at the boiling point

J/(kg K)J/(mol K)

s

d

mass [or molar] specific entropy at the dew point

J/(kg K)J/(mol K)

T

temperature

K

T

s

boiling temperature or saturation temperature

K

T

o

cooling temperature – temperature of the object being cooled

K

T

amb

ambient temperature = environment temperature or room temperature

K

T

c

critical temperature

K

u

fluid velocity

m/s

VF

vapor fraction = molar [or mass] fraction of liquid in a two-phase fluid/material stream

mol/molor kg/kg

W

mechanical work

J, kWh

x

i

molar [or mass] fraction of a component in liquid mixture

mol/molkg/kg

y

i

molar [or mass] fraction of a component in gaseous/vapor mixture

mol/molkg/kg

z

i

molar [or mass] fraction of a component in a mixture

mol/molkg/kg

Greek Symbols

γ

gamma = heat capacity ratio

c

p

/

c

v

= isentropic exponent for an ideal gas

–

ε

synonymous to coefficient of performance COP

–

κ

=

κ

kappa = isentropic exponent for a real gas

–

μ

Joule–Thomson coefficient

K/bar

μ

in chapter 4.4.1 it is used for chemical potential

J/mol

η

efficiency

η

e

exergy efficiency = Carnot efficiency

η

s

isentropic efficiency of a compressor stage or expander stage

η

T

isothermic efficiency of a multistage compressor

ɳ

LIQ

efficiency of a liquefier

π

pressure ratio in an expander or a compressor

ρ

density of fluid

kg/m

3

ϑ

temperature in °C

°C

λ

thermal heat conductivity

W/(m K)

Σ

sum

Mixed Symbols

Δ

h

v

molar [or mass] enthalpy of vaporization

J/kgJ/mol

Δ

Ḣ

WE

enthalpy [flow] difference at the warm end of a heat exchanger

kW

Δ

S

entropy rise

J/K

Δs

specific entropy rise

J/(mol K)

Δ

T

temperature difference

K

Δ

T

min

minimal temperature difference in a heat exchanger

K

Δ

T

max

maximal temperature difference in a heat exchanger

K

Δ

T

CE

temperature difference at the cold end of a heat exchanger

K

Δ

T

WE

temperature difference at the warm end of a heat exchanger

K

T

λ

temperature at λ – point (for liquid helium)

K

Subscripts

amb

used for ambient/environment conditions

c

used for cold objects (cold material streams, cold expanders and similar)

c

sometimes relates to critical states, for example, critical temperature

T

c

or critical pressure

p

c

Carnot

relates to Carnot process or generally to a reversible process

COMP

relates to compressor

EXP

relates to expander

g

used for gaseous phase

HP

relates to High Pressure level

i

used either for a mixture component i or for heat exchanger zone i

in

used for inlet streams (material streams, energy streams and other streams)

JT

used for Joule–Thomson (Joule–Thomson process, Joule–Thomson expansion and similar)

L

or

l

used for liquid phase

LP

relates to Low Pressure level

out

used for outlet streams (material streams, energy streams and other streams)

V

or

v

used for vapor phase

w

used for warm objects (warm material streams, warm expanders and similar)

1, 2, 3, 4, 5, etc

.

relate to corresponding state in process flow diagram

2phase

relates to two-phase state

Superscripts

COMP

relates to compressor

EXP

relates to expander

HEX

relates to heat exchanger

in

used for inlet streams (material streams, energy streams and other streams)

JT

relates to Joule Thomson valve

out

used for outlet streams (material streams, energy streams and other streams)

REF

or

o

relates to reference state

Further Abbreviation

AIR

air

CNG

compressed natural gas

GAN

gaseous nitrogen

GAP

gaseous air (pressurized)

GOX

gaseous oxygen

LAP

liquid air (pressurized)

LAR

liquid argon

LH2

liquid hydrogen

LHe or LHE

liquid helium

LIN

liquid nitrogen

LNG

liquefied natural gas

LOX

liquid oxygen

PGAN

pressurized gaseous nitrogen

Symbols Used for Process Flow Diagrams

gaseous material stream

liquid material stream

two-phase fluid

expander or turboexpander

expander with generator brake

expander-booster-combination

expander with oil brake or gas brake

expansion valve or Joule-Thomson-valve or control valve

multistage quasi-isothermic compressor unit

compressor (turbocompressor) stage or booster stage

water cooler (usually after a compressor unit)

phase separator

heat exchanger with a warm (red) and cold (blue) material streams

evaporator [or cold gas heat exchanger], where a heat flow (usually from object being cooled) is applied to a cooling fluid

1Introduction

Generally, refrigeration technology is the engineering science of how to cool a corresponding cooling object to a temperature below the ambient temperature and/or how to keep it cold continuously at this low temperature for the required time. Usually, the cooling is done by means of a special device – a refrigerator. Typical examples of refrigerators known from our everyday life are household refrigerators, chest freezers, and air conditioners.

Cryotechnology (from the ancient Greek κρύος (kryos) – cold, ice) is a part of refrigeration technology covering the range of very low temperatures (see Figure 1.1). In terms of numbers, probably, the most successful commercial cryosystem is the superconducting magnet at the core of an magnetic resonance imaging (MRI) system, as found in most large hospitals today. Other typical examples of cryosystems are helium liquefier, air separation plant, or liquid hydrogen storage.

Principally, the cryotechnology consists of two large areas: (i) technologies for use/application of very low-temperature cold and (ii) that for generation of cryogenic cold (see Figure 1.1). The latter is called cryogenics (also from ancient Greek κρύος (kryos) – cold, ice and γενεά (geneá) – generation, or γέεσι (génesis) – origin), which is literally translated as “deep cold generation.” A typical example of a cryogenic system is a helium liquefier. In contrast, a superconducting magnet at the core of MRI systems, as mentioned above, is a typical example of a cryo application.

In English-speaking community, the terms “cryogenic” and “cryogenics” are used often as synonym for “cryo” and “cryo technology”: a cryo application can be referred to as a “cryogenic application,” although no active cold generation takes place within such systems.

In cryogenic engineering, it is common to specify and define the temperature T in degrees Kelvin (K) as absolute temperature instead of relative temperature Θ usually measured in degrees Celsius (°C). The conversion is simple and is performed as follows:

Figure 1.1 Refrigeration technology.

The use of degrees Kelvin has the advantage of eliminating negative temperature values. The zero point is the absolute zero point. “That frees us from annoying minus signs and subtractions,” as Kurt Mendelssohn writes in [1].

According to the definition established during the 13th Congress of the International Institute of Refrigeration in Paris (1971), the formal boundary between conventional refrigeration and cryotechnology is a temperature of 120 K (approx. −153 °C), which corresponds to the liquefaction temperature of natural gas. This definition is to be considered in historical context – at that time, the first large natural gas liquefaction plants were being built, the business around liquefied natural gas (LNG) was booming, and technologies for this temperature level were emerging.

Although this 120 K-level definition was formally established, the discussion about the borderline between the cryo and the conventional refrigeration is still ongoing. The discussion as such does not generate any useful, applicable knowledge, but it provides an indication of what is the most emerging cryogenic application at the moment. For example, in the 1990s, when the first applications based on the so-called high-temperature superconductors (HTSCs) (see Section 1.2) were intensively developed, a lively debate revolved around the question of whether to reset the boundary temperature to the critical temperature of the best high-temperature superconductive materials.

Recently, the gas industry prefers to consider the temperature of 217 K (approx. −56 °C) as a practical boundary between cryotechnology and conventional refrigeration technology. This temperature corresponds to the triple point of carbon dioxide (CO2) and is attributed to increasing commercial value of this gas. The technology and the logistics chain for CO2 supply on an industrial scale closely resemble those of liquid oxygen or liquid nitrogen, and therefore liquid CO2 is often considered a cryogenic gas.

From a process design perspective (since this book is about process design), it would make sense to define the differentiation criteria based on thermodynamic process used in a plant. For example, a system based on a Joule–Thomson process or a mixed fluid Joule–Thomson process, Brayton process, Claude process, or cascade with more than two stages would be allocated to cryogenics, whereby a system based on the Rankine process or its derivates would be considered as conventional refrigeration technology.

This book is focused on cryogenics and cryogenic processes for temperatures below 120 K, according to the formal definition of cryogenics.

1.1 Historical Background

The era of cryogenics began with the liquefaction of oxygen, which was reported by two scientists – Louis Paul Cailletet and Raoul Pierre Pictet – in December 1877, independently from each other.1 It was a classical example of a disruptive development causing a considerable acceleration in corresponding science, in this case in cryogenics.

The oxygen liquefaction realized by Pictet and Cailletet was an exceptional achievement and must be highly honored. Science historians have pointed out the phenomenon that “at any given time there is a consensus among scientists of a given field regarding the fundamental hypotheses of their discipline” (see [2]). The “standard” theory at that time postulated that all known gaseous substances could be categorized into two groups:

gases which can be liquefied by compression and cooling, such as chlorine, ammonia, sulfur dioxide, hydrogen sulfide and

gases which cannot be liquefied at all, regardless of pressure and temperature conditions – the so-called “permanent” gases such as nitrogen, oxygen, or hydrogen.

This thermodynamic rule was accepted by most engineers/scientists without doubt. Only a minority – scientists like Pictet and Cailletet – dared to disbelieve and question the established theory. The exceptional achievement of Pictet and Cailletet was not only about the oxygen liquefaction, but it was more about breaking the rules.

After the announcement of the successful liquefaction of oxygen, the theory of permanent gases was suddenly (literally overnight) no longer valid. From this moment on, it was evident that all gases could be liquefied, without exception. The race for the liquefaction of permanent gases and thus “the quest for absolute zero” was opened at this moment. Only five years later, in April 1883, Karol Olszewski and Zygmunt Wroblewski (Cracow, Poland) succeeded in producing liquid air and later liquid nitrogen. This operation required a temperature of 77 K (−196 °C), 14° lower than the temperature of liquid oxygen (91 K ≈ −182 °C). It took another 15 years until hydrogen, with a boiling temperature of 20.1 K (−253 °C), was liquefied by James Dewar in London (1898). Ten years later (1908), Heike Kammerlingh Onnes was able to produce liquid helium in Leiden (Netherlands (NL)). The boiling temperature of helium is 4.2 K (≈−269 °C). This opened the domain of extremely low temperatures to scientists.

Further developments in cryogenics in the following years were dominated primarily by two communities:

Physicists and chemists, who made amazing and groundbreaking discoveries such as superconductivity or superfluidity (see

Table 1.1

) and

Innovators like Carl Linde, George Claude, or Samuel Collins, who launched commercial products, mostly cryogenic systems or cryogenic hardware components, and created the demand and market for cryogenic applications. Several examples are listed in

Table 1.2

.

Table 1.1 Milestones in cryogenic + science.

Year

Discovery/event

Temperature (K)

Scientist(s)

1911

Superconductivity

4.2

Heike Kammerlingh Onnes

1933

Meißner–Ochsenfeld effect

4.2

Walther Meißner, Robert Ochsenfeld

1938

Superfluidity

<2.7

Peter Kapitsa (original: Capița)

1957

Superconductivity (Bardeen-Cooper-Schrieffer (BCS)) theory

—

Bardeen, Cooper, Schrieffer

1972

Superfluidity in

3

He

0.002

David Lee, Robert Richardson, Douglas Osheroff

1986

High-temperature superconductivity

>35

Johannes Bednorz, Alexander Müller

2003

Nobel prize for physics

—

Vitaly Ginzburgh, Alexei Abrikosov, Anthony Leggett

2017

Nobel prize (chemistry) for cryo-electron microscopy

>4.2

Joachim Frank, Jacques Dubochet, Richard Henderson

Table 1.2 Milestones in cryogenic engineering.

Year

Innovation

Inventor(s)

1893

Dewar flask

James Dewar

1895

Industrial air liquefaction

Carl Linde

1902

Low-temperature piston expansion machine and Claude cycle

George Claude

1905

Industrial air separation

Carl Linde

1938

Centrifugal expander for air separation

Peter Kapitsa

1947

Industrial helium liquefaction plant

Samuel Collins

1952

Stirling cooler

J.W.L. Köhler

1957

Atlas rocket with liquid hydrogen as fuel

NASA, I am not sure about the name

1958

Superinsulation

I am not sure about the name

1958

Mixed gas cycle for natural gas liquefaction

A.P. Klimenko

1963

Gifford–McMahon cooler, pulse tube cooler

E. Gifford, R. Longsworth

1990s

Joule–Thomson expansion machine

I am not sure about the name

1990s

Cold compressor

I am not sure about the name

1990s

Structured packing for air separation plants, especially for cryogenic argon separation

Linde AG, I am not sure about the name

The discussion about which group – scientists with their discoveries, or innovators with their inventions – created a greater contribution to our culture is a confusing one. In reality, both these groups were linked so closely to each other that it is almost impossible to distinguish between them: the physicist James Dewar was also a great innovator. The same applies to Heike Kammerlingh Onnes or Peter Kapitsa, who not only discovered superfluidity, but also built the first industrial air separation plant with a turbo expander. Carl Linde, who founded the air separation industry, invested an immense amount of time in the development of an equation of state (similar to van der Waal’s equation). From the author’s point of view, both groups – scientists and innovators – emanated unbelievable creative impulses, and both groups were extremely “cool” (in the cryogenic sense).

1.2 Cryogenic Applications

Cryogenics is normally not of prime concern to its users. Instead, it is a sort of utility only for a primary application (for example, steelmaking). Two typical functions delivered by cryogenics are shown in Figure 1.2: either it provides a cooling capacity or it supplies the main application with the required industrial gases such as nitrogen, argon, oxygen, and hydrogen.

Use case cooling capacity

: The cooling capacity can be provided directly by a cryogenic refrigerator or indirectly in form of a liquefied cryogen (refrigerant), such as liquid helium or liquid nitrogen, which is filled into the corresponding device and usually evaporates during the operation of the application.

Use case gas supply

: there are two options available:

Remote cryogenic plant

: The required gas is produced and liquefied in a corresponding remote cryogenic production plant or facility, and the customer is supplied with compressed or liquefied gas (liquid oxygen, liquid nitrogen, etc.) by pipelines, trucks, or other transport methods. The delivered liquefied gas is evaporated on the customer’s site to provide the gas to the main application. This method is used for small and medium gas quantities (up to 20 t/d),

On-site cryogenic plant

: an appropriate cryogenic production plant is installed on the customer’s site directly. It supplies the application with the required amount of gas. This option is economically more feasible for large amounts of gas.

Almost all industrial gases can be produced by a non-cryogenic method as well. The decision for or against the cryogenic option is always based on techno-economic considerations according to the given requirements and conditions. The cryogenic system is usually a cost-intensive option. It is competitive only

- if the alternative technical solution is not able to deliver the required product quality (for example, the gas purity) or

- if high gas amount/flow produced by means of a large-scale cryogenic plant is required. Since the “economy of scale” works well in this case, a very competitive specific product cost can be easily achieved.

Figure 1.2 Cryogenics as utility.

Several typical cryogenic applications are briefly described in this chapter as a rough overview. For a deep dive into this topic, the book [3] is recommended.

1.2.1 Natural Gas Liquefaction

The largest cryogenic systems in the world are the so-called “base-load natural gas liquefaction plants.” The natural gas is mainly liquefied for logistics reasons: the density of the LNG is roughly 600 times higher than the density of natural gas under normal conditions; therefore, the transport of natural gas in form of LNG over longer distances provides a reasonable economic option in comparison to other transport methods, for example by means of a pipeline. A further valuable advantage of LNG transport is its flexibility in terms of geography: it is possible to supply customers at different destinations in different countries using the same ship. The pipeline-based logistics (the alternative option) does not provide a comparable flexibility.

In former times, the LNG industry was based primarily on individual, more or less self-contained projects that required immense capital investment (in the range of double-digit billions of US dollars) and which therefore were fraught with high risk. In the meantime, “the industry has proven its reliability and stability under different market and economic conditions. Currently, demand growth and high energy prices, coupled with advances in technology, are driving more planned and proposed LNG projects than at any point in history,” according to [4].

1.2.2 Cryogenic Air Separation

The second-largest cryogenic systems are air separation plants. With a double-digit number of plants installed or replaced annually, the air separation industry represents the largest market for cryogenic systems. Medium-size systems (10 000–90 000 m3