This document provides an overview of key concepts in process design including block diagrams (BD), process flow diagrams (PFD), piping and instrumentation diagrams (PID), standards, distributed control systems (DCS), and icon conventions. It discusses how BDs are developed into more detailed PFDs and PIDs. Standards that are normative and informative for process design are outlined. The goals of PFDs to present process information clearly and concisely are described. Isolation, insulation, heat tracing, and control systems are also briefly covered.

1. Faculty of Chemical
Engineering
Universiti Teknologi MARA
1
INTRODUCTION:
SCOPE OF PROCESS
DESIGN
Process Design (CGE 666)
WK 1-2

2. SCOPE OF PROCESS DESIGN
Flowsheet Architecture Concepts
• Block Diagram
• PFD and P&ID
• Design Pressure and Temperature
• Line Sizing
• System and Equipment Isolation
• Insulation and Heat Tracing
• Standards in process design; normative and
informative references
2

3. CONCEPTUAL STUDY
• The conceptual study is the first step of any
project.
• It investigates one or more means
(development schemes) of accomplishing the
objective.
• Economic and technical assessment and
comparison of the various methods or schemes
is made.
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4. CONCEPTUAL STUDY
• The analysis includes estimations of the timing
and amounts of all projected capital and
operating expenditures and related revenues.
• Economic assessments– Net Present Value
(NPV), Internal Return On Revenue (ROR),
payout period, percent profit
• The basic tools used in economically
assessing these various developmental
schemes are block diagrams and analyses of
alternative costs
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5. Block Diagram (BD)
The block diagram develops a selected process or
alternative into specific descriptions and
recommendations for equipment.
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6. 6
Conventions and Format Recommended for
Laying Out a Block Diagram
• Operations shown by blocks.
• Major flow lines shown with arrows giving direction of
flow.
• Flow goes from left to right whenever possible.
• Light stream (gases) toward top with heavy stream
(liquids and solids) toward bottom.
• Critical information unique to process supplied.
• If lines cross, then the horizontal line is continuous and
the vertical line is broken (hierarchy for all drawings in
this book).
• Simplified material balance provided.

7. Gas Facility Block Diagram
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Block Diagram (BD)

8. 8
Block Diagram (BD)

9. 9
Block Diagram (BD)

10. So, what sort of information can be gathered from BD? 10
Block Diagram (BD)

11.  Sketch a block diagram for oil facility.
 Explain the equipment used in the oil
facility(name of equipment and its function)
Hand drawing/writing
No cut/copy and paste
Due date: Next tutorial
11
Exercise 1

12. BD  Process Flow Diagram
 The block diagram is converted into a process
flow diagram (PFD)/process flowsheet to better
define the project.
 PFD shows all major equipments.
 It includes main piping with flow arrows, and
shows operation pressure and temperature of the
piping and equipment.
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13. Process Flow Diagram (PFD)/
Flowsheet
 Is a diagrammatic model of the process
 Shows the arrangement of equipment selected to
carry our the process
 Includes stream connections, names of streams,
stream flow rates compositions and operating
conditions (temp., Pressure)
 Main instruments
 Optional details of streams molar compositions
 Physical data (ρ, μ),code no. of streams,
Enthalpies of streams
 Brief description of stream 13

14. PFD
 PFD are intended to represent and explain
processes.
 To make them easy to understand, they are
constructed with a consistent set of symbols for
equipment, piping, and operating conditions.
 At present there is no generally accepted
industrywide body of drafting standards, although
every large engineering office does have its internal
standards.
 Some information appears in ANSI and British
Standards publications, particularly of piping
symbols.
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15. PFD
PFD are the
pictorial
representation
of the process
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16. PFDEquipmentSymbols
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17. PFDEquipmentSymbols
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18. PFD
 Process flowsheet/PFD does not show utilities, safety
systems, firewater systems, spare equipment, minor or
support lines, detailed instrumentation
 A table is included listing pertinent design data for these
streams. Data to be listed include flow rates, pressures,
temperatures, specific gravities, and other properties when
required.
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19. 19
The goal is to present the most amount of information with the least
amount of effort on the part of the reader.
• The flowsheet should generally flow from left to right.
• The flowsheet should not be cluttered - use multiple sheets.
• The flowsheet should be in landscape with the bound edge at top.
• The equipment should be drawn in approximately relative size, e.g.
towers larger than drums, exchangers larger than pumps etc.
• The major towers and reactors are generally on one, or nearly one,
level.
• The reader should be able to follow it with his or her eye.
• The streams should have the minimum of direction changes.
• The streams that enter across the battery limits should be on the left.
• The streams that leave across the battery limits should be on the right.
• The streams that move to the next sheet should leave on the right.
• The streams that recycle to earlier sheets should leave on the left.
PFD

20. 20

21. Refer sample flowsheet/PFD given.
 Example 1 – Gas Processing Plant
 Example 2 - Oil Production
Exercise – line tracing of Process
Flowsheet given
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Exercise 2

22. 22

23. Type of Diagrams
Block Diagram
Process Flow Diagram/Information
Flow Diagram
Material Flow Sheet
Energy Flow Sheet
Piping & Instrumentation Diagram
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24. 24

25. PIPING & INSTRUMENTATION DIAGRAM (PID)
 The process flow-sheet shows the arrangement of
the major pieces of equipment and their
interconnection. It is a description of the nature of
the process.
 The Piping and Instrument diagram (P and I
diagram or PID) shows the engineering details of
the equipment, instruments, piping, valves and
fittings; and their arrangement.
 It is often called the Engineering Flow-sheet or
Engineering Line Diagram.
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26. Distributed Control System (DCS)
Will be covered in the Chapter 7.
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27. System and Equipment Isolation
 It shall be possible to isolate equipment or process
sections during maintenance work to obtain safe
working conditions for the maintenance personnel.
 Process sections will also be isolated for leak testing
before commissioning, after a maintenance
operation, and for pressure testing.
 Will be covered in the Chapter 4.
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28. Insulation and Heat Tracing
• Heat tracing is used to prevent heat loss from process fluids
being transported in process fluid pipes, when there is risk of
damage to piping, or interference with operation such as
fouling or blockage, caused by the congealing, increase in
viscosity, or separation of components, in the fluid below
certain temperatures, or when there is risk of formation of
corrosive substances or water due to consideration in
corrosive services.
• This prevention of heat loss is accomplished by employing
electrical tracing, or steam tracing ad insulting both the
process fluid pipe and the tracer together, using appropriate
insulation materials and metal lagging is vital on any
application, in an attempt to reduce heat loss from the pipe
and tracer to their surroundings.
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29. STANDARDS IN PROCESS DESIGN
Normative Informative
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30. STANDARDS IN PROCESS DESIGN
Normative
 ANSI/ASME B31.3 Process Piping
 API RP 14C Analysis, Design, Installation and Testing
of Basic Surface Safety Systems on Offshore
Production Platforms. (New revision of ISO 10418 to
be used, when issued in 2000).
 API RP 520 Sizing, Selection and Installation of
Pressure-Relieving Systems in Refineries
 API RP 521 Guide for Pressure-Relieving and
Depressuring Systems.
 BS MA 18 Salt water piping systems in ships 30

31. STANDARDS IN PROCESS DESIGN
Informative
 API 2000 Venting Atmospheric and Low-Pressure Storage
Tanks
 API RP 14 E Design and Installation of Offshore
Production Platform Piping Systems.
 ISO/DIS-14313 Petroleum and Natural Gas Industries,
Pipeline, Check, Gate and Plugvalves
 ASME VIII Boiler and Pressure vessel code
 BS 5500 Unfired Fusion Welded Pressure Vessel Code.
 TBK 1-2 General Rules for Pressure Vessel
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32. PIPELINE CODES AND STANDARDS
• Pipeline systems are designed according to various
statutory and regulatory codes and standards.
Will be covered in the Chapter 3.
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33. ICON
Will be covered in the Chapter 6.
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34. CONCLUSIONS – Please
summarise this chapter!
BD
PFD
PID/PNID
STANDARDS
DCS
ICON
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