Process Equipment and Plant Design: Principles and Practices

Process Equipment and Plant Design: Principles and Practices
Copyright
Dedication
About the Authors
Preface
Acknowledgement
Introduction
1 . General aspects of process design
1.1 Process
1.2 Design problem and its documentation
1.3 The design process
Qualitative considerations can be
Quantitative considerations
Optimum design
Design steps
1.3.1 Deliverables
1.4 Organisation of the Book
Further reading
Introduction
2 . Heat transfer processes in industrial scale
2.1 Introduction
2.2 Exchanger types
2.2.1 Recuperator
2.2.2 Regenerator
2.2.3 Fluidised bed exchanger
2.2.4 Direct contact heat exchanger
2.3 Flow arrangement
2.3.1 Countercurrent flow exchanger
2.3.2 Co-current flow/parallel flow exchanger
2.3.3 Cross-flow exchanger
2.3.4 Split flow exchanger
2.3.5 Divided flow exchanger
2.3.6 Multipass exchanger
2.4 Exchanger selection
2.5 Heat exchanger design methodology
Process and design specifications
2.6 Design overview for recuperators
2.6.1 Thermal design
The effectiveness-NTU method
2.7 Estimation of overall design heat transfer coefficient
Further reading
3 . Double pipe heat exchanger
3.1 Introduction
3.2 Design
3.2.1 Input data
3.2.2 Deliverables
3.2.3 Codes and standards
3.2.4 Guidelines to select inner and outer fluid
3.2.5 Design considerations
3.2.6 Thermal design
3.2.7 Hydraulic design
3.3 Series-parallel configuration of hairpins
3.4 Design illustration
3.4.1 Design steps
3.4.2 Design example
References
Further reading
4 . Shell and tube heat exchanger
4.1 Introduction
4.1.1 General description
Shell
Exchanger Head(s)
Tubes
Tube sheet
Baffle
Tie rods and spacers
Impingement baffle
Multipass exchanger
Shell passes
4.1.2 Heat exchanger installations and commissioning
4.2 Codes and standards
4.3 Design considerations
Process
Mechanical
4.3.1 Input data for design
4.3.2 Design output
Process design
Mechanical details
Fabrication details
4.4 Design – FT method
4.5 Pressure drop estimation
4.6 Mechanical detailing
4.6.1 Exchanger material
4.6.2 Tube length
4.6.3 Tube sheet details
4.6.4 Tube pass pattern
4.6.5 Finned tubes
4.6.6 Segmental baffles (transverse baffles in BIS code)
4.6.7 Tie rods
4.6.8 Impingement baffle
4.6.9 Shell dimensions
4.6.10 Channel and channel cover
4.6.11 Nozzles
4.6.12 Exchanger support
4.7 Design illustration
Further reading
5 . Heat exchanger network analysis
5.1 Introduction
5.2 Energy-capital trade-off – two-stream problem
5.3 Multi-stream problem
5.3.1 Optimal ΔTmin
5.3.2 Practical values of ΔTmin
5.4 Pinch design analysis
5.4.1 Locating the pinch using the problem table algorithm
5.4.2 The pinch principle
5.4.3 Design strategy
5.4.4 Grid diagram
Tick off heuristic
5.4.5 Stream splitting in network design
5.4.6 Network simplification: heat load loops and heat load paths
5.5 Targeting for multiple utilities
5.6 Design algorithm
5.7 Threshold problems
5.8 Data extraction
5.8.1 Composite curve for non-linear CP
5.8.2 Avoid mixing of streams at different temperatures
5.8.3 Use effective temperatures
5.8.4 True utility streams
5.9 Applications
5.10 Design illustration
Composite curves
Problem table algorithm
Further reading
6 . Evaporators
6.1 Introduction
6.2 Components of an evaporation system
6.3 Evaporator types
6.3.1 Types of continuous evaporators
Evaporators without heating surfaces
6.4 Evaporator performance
6.4.1 Multiple-effect evaporators
Feeding arrangements
Use of vapor as a “hot stream” in the plant
6.4.2 Vapor recompression
6.4.3 Heat recovery systems
6.4.4 Evaporator selection
6.5 Evaporator accessories
6.5.1 Condensers
6.5.2 Vent systems
Salt removal
6.6 Evaporator design
6.6.1 Single-effect evaporation
6.6.2 Multiple effect evaporation
Optimum number of effects in a multiple-effect system
6.6.3 Design data
Elevation of boiling point (BPE)
Boiling point elevation in multiple effect evaporators
Enthalpy plots
Tsteam & Tcon
Steam pressure
Pressure in the vapor space
Influence of feed, steam and condensate temperature
6.6.4 Design algorithm for multiple-effect evaporator
Design input
Design objective
Design deliverables
Design algorithm
6.7 Design illustration
Design example 1
Process design deliverables
Design example 2
Deliverables
Further reading
7 . Industrial cooling systems
7.1 Introduction
7.2 Cooling tower
7.2.1 Classification
Classification by build
Classification based on air draft
Classification based on airflow pattern
Classification based on the heat transfer method
7.2.2 Components of a typical cooling tower
7.2.3 Cooling tower parameters
7.2.4 Cooling water circuit in a process plant
7.2.5 Codes and standards
7.2.6 Thermal design
7.2.7 Notes on design and operation
7.3 Design illustration
Summary of available data
Tower selection
Fill details
Determination of operating L/G for the fill chosen
Steps of calculation
Fan power calculation
Estimating head loss in the fill and water distributor level
Estimating make up water (M) requirement
Evaporation loss (E)
Drift loss (D)
Pump calculations
Cooling tower sump
Further reading
Introduction
8 . Interphase mass transfer
8.1 Introduction
8.2 Processes and equipment
8.3 Process design and detailed design of the equipment
9 . Phase equilibria
9.1 Introduction
9.2 Representation of concentration
9.3 Representation of equilibrium
9.3.1 Graphical representation of equilibrium
9.3.2 Mathematical representation of equilibrium
VLE: Distillation
Solubility: absorption and stripping
GSE and LSE: adsorption
LLE: extraction
Further reading
10 . Absorption and stripping
10.1 Introduction
10.2 Tray column
10.2.1 Graphical determination of the number of contacting stages
Minimum required liquid flow rate (Lmin) in case of absorber for a given gas rate (G,G′)
Approximations for low concentration system
10.2.2 Absorption factor
10.3 Packed column
10.3.1 Packed column design based on mass transfer coefficient
10.3.2 Driving force line
10.3.3 Overall mass transfer coefficient
10.3.4 Estimation of active bed height
10.3.5 Design based on liquid-phase resistance
10.3.6 Absorption accompanied by chemical reaction
10.4 Design illustration
Driving force lines
Estimating mass transfer coefficients
Further reading
11 . Distillation
11.1 Introduction
11.2 Conceptual design
11.3 Detailed design
11.4 Fractionator
11.4.1 Process design of fractionating tower – equilibrium stage approach
11.4.2 Binary fractionation
11.4.3 Multicomponent distillation
11.5 Design illustration – fractionator
11.6 Flash distillation
11.6.1 Design equations
11.6.2 Design considerations
11.6.3 Design steps
11.7 Design illustration – flash distillation
11.8 Batch distillation
11.8.1 Design
11.8.2 Design deliverables
11.8.3 Design steps
11.9 Design illustration – batch distillation
Further reading
12 . Adsorption
12.1 Introduction
12.1.1 Modes of operation
Stagewise operation
Continuous contact operation
12.1.2 Adsorption mechanisms
12.1.3 Adsorption equilibrium
12.2 Packed bed adsorption
12.2.1 Breakthrough curve, breakthrough point, and bed exhaustion
12.2.2 Desorption/regeneration
Gas-phase adsorption
Liquid-phase adsorption
12.2.3 Adsorbent aging
12.2.4 Bed design
Rigorous methods
Empirical or short-cut methods
Pilot plant design
Data/information required for design
Operating parameters from pilot tests
(a) Loading rate/filtration rate (LR) for liquid-phase applications
(b) Superficial velocity (Us) for gas-phase applications
(c) Empty bed contact time
(d) Breakthrough time (tb)
(e) Fraction of bed utilised (f)
(f) Adsorbate loading (qs)
Bed design
Volume of fluid treated/change out period
Pressure drop
Bed configuration and mode of operation
12.3 Design illustration
Further reading
13 . Extraction
13.1 Introduction
13.2 Extractor types and selection
13.2.1 Extractor types
Stagewise contact
Continuous contact
13.2.2 Contactor selection
13.3 Choice of solvent
13.4 Design of continuous countercurrent contactors
Flooding
13.4.1 Calculation of the number of stages
13.4.2 Design parameters for extraction towers
13.5 Design of mixer-settler
13.5.1 Holding time
13.5.2 Power and mixing time
13.5.3 Scale-up
13.5.4 Flow mixers
13.6 Design illustrations
Further reading
14 . Column and column internals for gas–liquid and vapour–liquid contacting
14.1 Introduction
14.2 Tray towers
14.2.1 Contacting trays
Downcomer
Outlet weir
Liquid bypass baffles
Bottom tray seal pan
Weep holes
Vapour disperser elements
14.2.2 Choice of tray type
14.2.3 Tray construction
14.2.4 Efficient operation of contacting tray
14.3 Tray design
14.3.1 Bubble cap tray design
Tower diameter
Check for entrainment
Tray passes
Outlet weir
Height over weir
Downcomer area
Cap size
Number of caps
Area fractions over tray
Liquid gradient across tray
Tray pressure drop (htray, mm of liquid)
Check for vapour distribution
Vapour velocity and corrected ‘approach to flooding’
Downcomer pressure drop (hdc,prdrop, mm of liquid)
Downcomer backup (hL,dc, mm of liquid, for all cross-flow trays)
Velocity and residence time in downcomer
Downcomer throw over the weir
System (foaming) factors (applicable for all cross-flow trays)
Weep holes
14.3.2 Sieve tray design (cross-flow type – with downcomer)
Steps of design
14.3.3 Valve tray design
14.4 Packed tower
14.4.1 Choice of packing
Packing types and size
14.4.2 Liquid distribution
Liquid distributor
Redistributor and collector
14.4.3 Bed support
14.4.4 Flooding and pressure drop in randomly packed bed
Bed diameter estimation based on flooding and pressure drop
Pressure gradient
Minimum wetting rate
14.5 Packed tower design
14.6 Chimney tray, reflux entry, feed tray and tower bottom
14.6.1 Chimney tray
14.6.2 Reflux entry arrangement on top tray
14.6.3 Feed tray
14.6.4 Tower bottom arrangement
14.7 Design illustration
Further reading
Introduction
15 . Reactors and reactor design
15.1 Introduction
15.2 Design of reacting system
15.2.1 Reactor types
15.2.2 Rate and extent of reaction
Rate-limiting step
15.3 Reactor design
15.3.1 Reaction/process conditions
15.3.2 Design deliverables
Performance equation for idealized reactors
15.3.3 Scale-up
15.3.4 Bioreactors
Sterilization
15.4 Design illustration
Further reading
Introduction
16 . Plant hydraulics
16.1 Introduction
16.2 Pumps
16.2.1 Common pump types
Centrifugal Pump
Positive displacement pumps
Reciprocating pumps
Rotary pumps
Diaphragm pump
16.2.2 Pump performance and hydraulics
16.2.3 Cavitation
NPSH in centrifugal pump
Liquid vapour pressure
NPSH in reciprocating pumps
16.2.4 Characteristic curve for centrifugal pumps
Q-H curve
Pumps in series and parallel
Q-SHP (or BHP) Curve
Q-NPSHRCurve
16.2.5 System characteristic curve
16.2.6 Adjusting centrifugal pump performance
16.2.7 Characteristic curves for positive displacement pumps
16.2.8 Pump selection
16.2.9 Steps of design for a hydraulic circuit
16.3 Compressors
16.3.1 Compressor selection
16.3.2 Centrifugal compressor
Characteristic curve
16.3.3 Compressor hydraulics
Capacity and pressure ratio
Power
Head developed
16.3.4 Design/sizing
16.3.5 Capacity control
16.4 Piping
16.4.1 Piping codes
16.4.2 Pipe size
16.4.3 Piping services
16.4.4 Pipe rack
16.4.5 Pipe joints
16.4.6 Pipe fittings
Pressure relief–safety devices
Other fittings
16.4.7 Pressure drop in pipeline
16.4.8 Few typical process piping systems
Purge out operation
Vent and drain system
Flushing connections
Control valve installation
Steam trap
Good practices for piping layout
16.5 Hydraulic calculations
Further reading
17 . Process vessels
17.1 Unfired pressure vessels
17.2 Vessel components and fixtures
17.3 Mechanical design
17.3.1 Design Parameters
17.3.2 Vessel sizing
Vapour-liquid separator
Separator with wire mesh mist eliminator (demister pad)
Reflux drum
Liquid-liquid separator
17.3.3 Nozzle dimensions and location
17.3.4 Manhole specifications
17.3.5 Wall thickness
17.4 Design illustrations
Further reading
Introduction
18 . Utility services in process plants
18.1 Introduction
18.2 Fuel systems
18.2.1 Fuel gas
18.2.2 Fuel oil
18.2.3 Design of fuel system
18.3 Electrical power
18.4 Steam
18.5 Compressed air
18.5.1 Air supply scheme
18.5.2 Design illustration – compressed air system
18.6 Inert gases
18.7 Water
18.8 Efficient use of utilities
Further reading
19 . Plant instrumentation and control
19.1 Introduction
19.2 Control loop
19.2.1 Feeback and feedforward
Selection–feedback versus feedforward
19.2.2 Characteristic features of a process being controlled
19.3 Analog signals–pneumatic and electronic
19.4 Control algorithms
19.4.1 P, PI and PID controllers
Choice of P, PI, or PID controller
19.4.2 Few advanced configurations of controllers
Cascade control
Split range control
19.5 Measurement of process parameters
19.5.1 Temperature measurement
Thermocouple versus RTD
19.5.2 Pressure measurement
Measurement of differential pressure
19.5.3 Flow measurement
19.5.4 Level measurement
19.6 Control valves
19.6.1 Fail-open and fail-close valves
19.6.2 Valve size
19.7 Instrumentation for safety
19.8 Distributed control system (DCS)
19.9 Control schemes for common processes
19.9.1 Distillation control and instrumentation
19.9.2 CSTR instrumentation and control
Further reading
20 . Engineered safety
20.1 Introduction
20.2 Hazardous area classification
20.3 Trips and alarms
20.4 Blowdown and flare
20.4.1 Blowdown
20.4.2 Safety and pressure relief valves
20.4.3 Flare system
20.5 HAZOP
Problem statement
Report
Major recommendations
Worksheets
Worksheet WS–1
Worksheet WS–2
Further reading
Introduction
21 . Process packages
21.1 Process package deliverables
21.2 Examples
21.2.1 Design illustration 1
Design of 10,000 MT/Annum plant to manufacture Ethyl acetate from Ethanol
21.2.2 Design illustration 2
Design of a facility for a refinery to treat 8000m3/d of wastewater
Further reading
Graphical symbols for piping systems and plant
Based on BS 1553: PART 1: 1977
Scope
Appendix B: Corrosion chart
Physical property data bank
Conversion factors
Typical fouling factors in m2K/W compiled from various sources
Heat exchanger tube sizes and other details
List of different standards commonly used
Index
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W