Industrial Separation Processes: Fundamentals

✍ Scribed by André B. de Haan; Hans Bosch

• Publisher: De Gruyter
• Year: 2013
• Tongue: English
• Leaves: 384
• Category: Library

✦ Synopsis

TU Eindhoven: best MSc lecturer 2014

Separation operations are crucial throughout the process industry with respect to energy consumption, contribution to investments and ability to achieve the desired product with the right specifications.

Our main objective in creating this graduate level textbook is to present an overview of the fundamentals underlying the most frequently used industrial separation methods. We focus on their physical principles and the basic computation methods that are required to assess their technical and economical feasibility.

The textbook is organized into three main parts. Separation processes for homogeneous mixtures are treated in the parts on equilibrium based molecular separations and rate-controlled molecular separations. The part on mechanical separation technology presents an overview of the most important techniques for heterogeneous mixture separation. Each chapter provides a condensed overview of the most commonly used equipment types. The textbook is concluded with a final chapter on the main considerations in selecting an appropriate separation process for a separation task.

As the design of separation processes can only be learned by doing, we have included exercises at the end of each chapter. Short answers are given at the end of this book; detailed solutions are given in a separate solution manual.

• Authoritative introduction to industrial separation technology
• Contains exercises at the end of each subject and solutions
  

✦ Table of Contents

1 Characteristics of separation processes
1.1 Significance of separations
1.2 Characteristics of separation processes
1.2.1 Categorization
1.2.2 Separating agents
1.2.3 Separation factors
1.3 Industrial separation methods
1.3.1 Exploitable properties
1.3.2 Important molecular separations
1.4 Inherent selectivities
1.4.1 Equilibrium based processes
1.4.2 Rate controlled processes
2 Evaporation and distillation
2.1 Separation by evaporation
2.1.1 Introduction
2.1.2 Vapor-liquid equilibria
2.2 Separation by single-stage partial evaporation
2.2.1 Differential distillation
2.2.2 Flash distillation
2.2.2.1 Specifying T and L/V
2.2.2.2 Specifying T and Ptot
2.3 Multistage distillation
2.3.1 Distillation cascades
2.3.2 Column distillation
2.3.3 Feasible distillation conditions
2.3.4 External column balances
2.4 McCabe-Thiele analysis
2.4.1 Internal balances
2.4.1.1 Rectifying section
2.4.1.2 Stripping section
2.4.1.3 Feed stage considerations
2.4.1.4 Feed line
2.4.2 Required number of equilibrium stages
2.4.2.1 Graphical determination of stages and location of feed stage
2.4.2.2 Limiting conditions
2.4.2.3 Fenske and underwood equations
2.4.2.4 Use of murphree efficiency
2.4.3 Energy requirements
2.5 Advanced distillation techniques
2.5.1 Batch distillation
2.5.2 Continuous separation of multiple product mixtures
2.5.3 Separation of azeotropes
3 Absorption and stripping
3.1 Introduction
3.2 The aim of absorption
3.3 General design approach
3.4 Absorption and stripping equilibria
3.4.1 Gaseous solute solubilities
3.4.2 Minimum absorbent flow
3.5 Absorber and stripper design
3.5.1 Operating lines for absorption
3.5.2 Stripping analysis
3.5.3 Analytical kremser solution
3.6 Industrial absorbers
3.6.1 Packed columns
3.6.2 Plate columns
3.6.3 Spray and bubble columns
3.6.4 Comparison of absorption columns
4 General design of gas/liquid contactors
4.1 Introduction
4.2 Modeling mass-transfer
4.3 Plate columns
4.3.1 Dimensioning a tray column
4.3.2 Height of a tray column
4.3.3 Diameter of a tray column
4.4 Packed columns
4.4.1 Random packing
4.4.2 Structured packing
4.4.3 Dimensioning a packed column
4.4.4 Height of a packed column
4.4.5 Minimum column diameter
4.4.6 Pressure drop
4.5 Criteria for column selection
5 Liquid-liquid extraction
5.1 Liquid-liquid extraction
5.1.1 Introduction
5.1.2 Liquid-liquid equilibria
5.1.3 Solvent selection
5.2 Extraction schemes
5.2.1 Single equilibrium stage
5.2.2 Cocurrent cascade
5.2.3 Crosscurrent
5.2.4 Countercurrent
5.3 Design of countercurrent extractions
5.3.1 Graphical McCabe-Thiele method for immiscible systems
5.3.2 Analytical kremser method
5.3.3 Graphical method for partial miscible systems
5.3.4 Efficiency of an ideal non-equilibrium mixer
5.4 Industrial liquid-liquid extractors
5.4.1 Mixer-settlers
5.4.2 Mechanically agitated columns
5.4.3 Unagitated and pulsed columns
5.4.4 Centrifugal extractors
5.4.5 Selection of an extractor
6 Adsorption and ion exchange
6.1 Introduction
6.2 Adsorption fundamentals
6.2.1 Industrial adsorbents
6.2.2 Equilibria
6.2.3 Kinetics
6.3 Fixed-Bed adsorption
6.3.1 Bed profiles and breakthrough curves
6.3.2 Equilibrium theory model
6.3.3 Modeling of mass transfer effects
6.4 Basic adsorption cycles
6.4.1 Temperature-swing
6.4.2 Pressure-swing
6.4.3 Inert and displacement purge cycles
6.5 Principles of ion exchange
6.5.1 Ion exchange resins
6.5.2 Equilibria and selectivity
6.6 Ion exchange processes
7 Drying of solids
7.1 Introduction
7.2 Humidity definitions of carrier gas
7.2.1 Definitions
7.2.2 System air-water: a special case
7.2.3 Psychrometric charts
7.3 Moisture in solids
7.3.1 Bound and unbound water
7.4 Drying mechanisms
7.4.1 Constant drying rate
7.4.2 Falling drying rate
7.4.3 Estimation of drying time
7.5 Classification of drying operations
7.5.1 Direct-Heat dryers
7.5.2 Contact dryers
7.5.3 Other drying methods
8 Crystallization and precipitation
8.1 Introduction
8.2 Crystal characteristics
8.2.1 Morphology
8.2.2 Crystal size distribution
8.3 Crystallization operating modes from solutions
8.3.1 Operating modes
8.3.2 Cooling crystallizers
8.3.3 Evaporating and vacuum crystallizers
8.3.4 Continuous crystallizers
8.3.5 Basic yield calculations
8.4 Crystallizer modeling and design
8.4.1 Supersaturation and metastability
8.4.2 Nucleation
8.4.3 Crystal growth
8.4.4 Population balance equations for the MSMPR crystallizer
8.5 Other crystallization techniques
8.5.1 Precipitation
8.5.2 Melt crystallization
9 Sedimentation and settling
9.1 Introduction
9.2 Gravity sedimentation
9.2.1 Sedimentation mechanisms
9.2.2 Dilute sedimentation
9.2.3 Hindered settling
9.2.4 Continuous sedimentation tank (gravity settling tank)
9.2.5 Gravity sedimentation equipment
9.3 Centrifugal sedimentation
9.3.1 Particle velocity in a centrifugal field
9.3.2 Sedimenting centrifuges
9.3.3 Bowl centrifuge separation capability
9.3.4 The sigma concept
9.3.5 Capacity of disc centrifuges
9.3.6 Hydrocyclones
9.4 Electrostatic precipitation
9.4.1 Principles
9.4.2 Equipment and collecting efficiency
10 Filtration
10.1 The filtration processfiltration process
10.2 Filtration fundamentals
10.2.1 Flow through packed beds
10.2.2 Cake filtration
10.2.3 Constant pressure and constant rate filtration
10.2.4 Compressible cakes
10.3 Filtration equipment
10.3.1 Continuous large-scale vacuum filters
10.3.2 Batch vacuum filters
10.3.3 Pressure filters
10.4 Filter media
10.5 Centrifugal filtration
10.5.1 Centrifugal filters
10.5.2 Filtration rates in centrifuges
10.6 Interceptive filtration
10.6.1 Deep bed filtration
10.6.2 Impingement filtration of gases
10.6.3 Interception mechanisms
10.6.4 Lamellar plate separators
11 Membrane filtration
11.1 Introduction
11.2 Membrane selection
11.3 Membrane filtration processes
11.4 Flux equations and selectivity
11.4.1 Flux definitions
11.4.2 Permeability for diffusion in porous membranes
11.4.3 Permeability for solution-diffusion in dense membranes
11.4.4. Selectivity and retention
11.5 Concentration polarization
11.6 Membrane modules
11.6.1 Design procedure
11.6.2 Solution
11.7 Concluding remarks
12 Separation method selection
12.1 Introduction
12.1.1 Industrial separation processes
12.1.2 Factors influencing the choice of a separation process
12.1.2.1 Economics
12.1.2.2 Feasibility
12.1.2.3 Product stability
12.1.2.4 Design reliability
12.2 Selection of feasible separation processes
12.2.1 Classes of processes
12.2.2 Initial screening
12.2.3 Separation factor
12.3 Separation of homogeneous liquid mixtures
12.3.1 Strengths of distillation
12.3.2 Limitations of distillation
12.3.3 Low relative volatilities
12.3.4 Overlapping boiling points
12.3.5 Low concentrations
12.3.6 Dissolved solids
12.4 Separaton systems for gas mixtures
12.4.1 General selection considerations
12.4.2 Comparison of gas separation
12.4.2.1 Absorption
12.4.2.2 Adsorption
12.4.2.3 Membrane separation
12.5 Separation methods for solid-liquid mixtures
Appendix
Answers to exercises
References and further reading
Index