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OBJECTIVES
After studying this chapter, the student will be able to:
•
•
•
•
•
Review process diagram symbols.
Describe the use of process diagrams and the information they contain.
Draw a process flow diagram.
Draw a process and instrument drawing.
Describe the various process equipment relationships.
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Key Terms
Electrical drawings—symbols and diagrams that depict an electrical process.
Elevation drawings—a graphical representation that shows the location of process equipment in
relation to existing structures and ground level.
Equipment location drawings—show the exact floor plan for location of equipment in relation to
the plan’s physical boundaries.
Flow diagram—a simplified sketch that uses symbols to identify instruments and vessels and to
describe the primary flow path through a unit.
Foundation drawings—concrete, wire mesh, and steel specifications that identify width, depth,
and thickness of footings, support beams, and foundation.
Legends—a document used to define symbols, abbreviations, prefixes, and specialized equipment.
Process and instrument drawing (P&ID)—a complex diagram that uses process symbols to
describe a process unit; also called piping and instrumentation drawing.
Types of Process Diagrams
Process diagrams can be broken down into two major categories: process
flow diagrams (PFDs) and process and instrument drawings (P&IDs),
sometimes called piping and instrumentation drawings. A flow diagram is a
simple illustration that uses process symbols to describe the primary flow
path through a unit. A process flow diagram provides a quick snapshot of
the operating unit. Flow diagrams include all primary equipment and flows.
A technician can use this document to trace the primary flow of chemicals
through the unit. Secondary or minor flows are not included. Complex control loops and instrumentation are not included. The flow diagram is used
for visitor information and new employee training.
A process and instrument drawing is more complex. The P&ID includes a
graphic representation of the equipment, piping, and instrumentation. Modern process control can be clearly inserted into the drawing to provide a
process technician with a complete picture of electronic and instrument
systems. Process operators can look at their process and see how the engineering department has automated the unit. Pressure, temperature, flow,
and level control loops are all included on the unit P&ID.
Basic Instrument Symbols
Process technicians use P&IDs to identify all of the equipment, instruments, and piping found in their units. New technicians use these drawings
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Basic Instrument Symbols
VALVES
S
Gate
Valve
Needle
Globe
Valve
Four-Way
Diaphragm
Angle
Manual
Operated Gauge
Valve
H
Solenoid
Valve
CLOSED
Hydraulic
Back
Pressure
Regulator
Back
Pressure
Regulator
Pneumatic
Operated
Three-Way
Valve
Butterfly
M
Ball
Bleeder
Valves
Plug
Check Valve
Orifice
COMPRESSORS
Reciprocating
Compressor
Pneumatic
Operated
Butterfly Valve
Motor
Rotameter
Relief
PRV
Safety
PSV
PUMPS & TURBINE
Vacuum
Pump
Centrifugal
Pumps
Centrifugal
Compressor
Compressor &
Silencers
Vertical
T
Liquid Ring
Compressor
Rotary
Compressor
Screw Pump
Centrifugal Compressor
(Turbine Driven)
Turbine
Gear Pump
HEAT EXCHANGERS
LINE SYMBOLS
Future Equipment
Major Process
Hairpin Exchanger
U-Tube
Heat Exchanger
Shell & Tube Heat Exchanger
Minor Process
Pneumatic
Hydraulic
Capillary Tubing
Single Pass
Heat Exchanger
Reboiler
L L L
X X XXX
X
Electromagnetic Signal
Heater
Condenser
Electric
VESSELS
Drum or Condenser
Mixer
Tank
TI
Temp Indicator
TT
Temp Transmitter
TR
Temp Recorder
LI
Level Indicator
LT
Level Transmitter
LC
Level Controller
FI
Flow Indicator
Mixing Reactor
Forced-Draft Cooling Tower
Tower
Bin
Furnace
Figure 12.1a
Induced-Draft Cooling Tower
Tower
with Packing
FT
Flow Transmitter
FR
Flow Recorder
PI
Pressure Indicator
PT
Pressure Transmitter
PRC
Pressure Recording
Controller
Process and Instrument Symbols
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TI
I
Flow Indicator
Temp Indicator
FI
TT
Temp Transmitter
FT
Flow Transmitter
PIC
105
Pressure Indicating
Controller
TR
Temp Recorder
FR
Flow Recorder
PRC
40
Pressure Recording
Controller
TC
Temp Controller
FC
Flow Controller
LA
25
Level Alarm
LI
Level Indicator
PI
Pressure Indicator
FE
Flow Element
LT
65
Level Transmitter
PT
55
Pressure Transmitter
TE
Temperature Element
LR
65
Level Recorder
PR
55
Pressure Recorder
LG
Level Gauge
LC
65
Level Controller
PC
55
Pressure Controller
AT
Analyzer Transmitter
P
Variable Being
Measured
What It Does
Transducer
Instrument
FIC
55
Control Loop
Figure 12.1b
Field Mounted
Remote Location
(board mounted)
Remote Location
(behind control panel)
Process and Instrument Symbols (continued)
during their initial training period. Knowing and recognizing these symbols
is important for a new technician. The chemical processing industry has assigned a symbol for each type of valve, pump, compressor, steam turbine,
heat exchanger, cooling tower, basic instrumentation, reactor, distillation
column, furnace, and boiler (Figure 12.1). There are symbols to represent
major and minor process lines and pneumatic, hydraulic, or electric lines,
and there is a wide variety of electrical symbols.
Flow Diagrams
New technicians are required to study a simple flow diagram of their assigned operating system. Process flow diagrams typically include the major
equipment and piping path the process takes through the unit. As operators
learn more about symbols and diagrams, they graduate to the much more
complex P&IDs.
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Cooling Tower
Vacuum Pump
Product
Tank
1
Drum
Furnace
Feed Tank
Column
Reactors
Product
Tank
2
Bottoms Tank
Boiler
Figure 12.2
Process Flow Diagram (PFD)
Some symbols are common among plants; others differ from plant to plant.
Some standardization of process symbols and diagrams is taking place.
The symbols used in this chapter reflect a wide variety of petrochemical
and refinery operations.
Figure 12.2 is a PFD that shows the basic relationships and flow paths
found in a process unit. It is easier to understand a simple flow diagram if it
is broken down into sections: feed, preheating, the process, and the final
products. This simple left-to-right approach allows a technician to identify
where the process starts and where it will eventually end. The feed section
includes the feed tanks, mixers, piping, and valves. In the second step, the
process flow is gradually heated for processing. This section includes heat
exchangers and furnaces. In the third section, the process is included. Typical examples found in the process section could include distillation
columns or reactors. The process area is a complex collection of equipment
that works together to produce products that will be sent to the final section.
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Process and Instrument Drawings
A P&ID is a complex representation of the various units found in a plant
(Figure 12.3). It is used by people in a variety of crafts. The primary users
of the document after plant startup are process technicians and instrument
and electrical, mechanical, safety, and engineering personnel.
In order to read a P&ID, the technician needs an understanding of the
equipment, instrumentation, and technology. The next step in using a P&ID
is to memorize your plant’s process symbol list. This information can be
found on the process legend. Process and instrument drawings have a variety of elements, including flow diagrams, equipment locations, elevation
plans, electrical layouts, loop diagrams, title blocks and legends, and foundation drawings. The entire P&ID provides a three-dimensional look at the
various operating units in a plant.
Process Legend
The process legend (Figure 12.4) provides the information needed to interpret and read the P&ID. Process legends are found at the front of the P&ID.
The legend includes information about piping, instrument and equipment
P-12
CT-105
V-2
V-3
PC
P-13
I/P
PCV
PT
D-105
LT
Tk-10
Tk-12
V-4
C-105
Rx-105
V-5
I/P
TT
FT
V-1
I/P
P-14
F-105
FC
LC
FCV
P-10
V-6
Tk-14
TC
LT
TE
TT
TC
I/P
Rx-106
I/P
P-15
LC
I/P
EX-105
Tk-16
P-11
Figure 12.3
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V-7
Process and Instrument Diagram (P&ID)
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Process and Instrument Drawings
VALVE SYMBOLS
Ball
Gate
Valve
Bleeder
Valves
Minor Process
Pneumatic
Pneumatic
Angle
Globe
Valve
Future Equipment
Major Process
Manual
Operated
Valve
Pneumatic
Plug
Knife Valve
SAFETY (Gases)
Pinch Valve
Relief
Valve
Solenoid Valve
CLOSED
Diaphragm
Four-Way
Hydraulic
INDUCED DRAFT
Crossflow
Butterfly
S
Check
Valve
LINE SYMBOLS
EQUIPMENT CONT.
X
Mechanical Link
• • • •
X
X
X
Electromagnetic, Sonic
Optical, Nuclear
Electric
Stop Check
Three-Way
Valve
EQUIPMENT SYMBOLS
L L L
Capillary Tubing
Connecting Line
NATURAL DRAFT
Counterflow
Non-Connecting Line
Non-Connecting Line
Jacketed or Double Containment
Vacuum
Pump
Horizontal
Software or Data Link
Vertical
INSTRUMENT SYMBOLS
Sump Pump
BOILER
Orifice
TI
Temp. Indicator
FI
Flow Indicator
TT
Temp. Transmitter
FT
Flow Transmitter
TR
Temp. Recorder
FR
Flow Recorder
TC
Temp. Controller
FC
Flow Controller
LI
Level Indicator
PI
Pressure Indicator
LT
65
Level Transmitter
PT
55
Pressure Transmitter
LR
65
Level Recorder
PR
55
Pressure Recorder
LC
65
Level Controller
PC
55
Pressure Controller
FE
Flow Element
I
Transducer
Centrifugal
Rotameter
Gear
Pump
Positive
Displacement
FURNACE
Rotary Screw
Compressor
Gauge
Reciprocating
Pump
Single
Pass
Demister
Screw Pump
Chimney
Progressive Cavity
Two Pass
Spray
Nozzle
Packed
Section
P
Draw Off
C
C
Double-Pipe
Spiral Heat
Heat Exchanger Exchanger
Generic
Tray
TE
Temperature Element
PIC
105
Pressure Indicating
Controller
LG
Level Gauge
PRC
40
Pressure Recording
Controller
AT
Analyzer Transmitter
Manway
Plate and Frame
Heat Exchanger
Vortex
Breaker
LA
25
Level Alarm
P
Air Cooled Exchanger
(Louvers Optional)
C
E
Drum
APPROVED
Dome Roof
Tank
Sphere
10-6-99
DATE
GENERAL LEGEND
Condenser
DISTILLATION UNIT
Cone Roof
Tank
Internal Floating
Roof Tank
DRAWING NUMBER
OO6543
REVISION 1
PAGE 1 OF 30
Heater
ABBREVIATIONS
PREFIXES
CW- cooling water
MU- makeup
FW- feed water
SE- sewer
Figure 12.4
RX- reactor
UT- utilities
CA- chemical addition
IA- instrument air
D- drum
C- column
CT- cooling tower
TK-tank
F- furnace
EX- exchanger
P- pump
V- valve
Process Legend
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S
4"
18"
W
E
Remesh
12"
N
2' x 64' x 18"
Load-Bearing
Beam
Rebar in
All Beams
32' 0"
Remesh
Over Plastic
Remesh
6-8-10 Method
6' 0"
10' 0"
28' 0"
90
8' 0"
28' 0"
64' 0"
Estimating Materials:
Figure 12.5
cu. yds. =
width x length x thickness
27
Foundation
symbols, abbreviations, unit name, drawing number, revision number,
approvals, and company prefixes. Because symbol and diagram standardization is not complete, many companies use their own symbols in unit
drawings. Unique and unusual equipment will also require a modified symbols file.
Foundation Drawing
The construction crew pouring the footers, beams, and foundation uses
foundation drawings (Figure 12.5). Concrete and steel specifications are
designed to support equipment, integrate underground piping, and provide
support for exterior and interior walls. Process technicians do not typically
use foundation drawings, but these drawings are useful when questions
arise about piping that disappears under the ground and when new equipment is being added.
Elevation Drawing
Elevation drawings (Figure 12.6) show the location of process equipment
in relation to existing structures and ground level. In a multistory structure,
the elevation drawing provides the technician with information about
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RX-300
TK-300
Figure 12.6
Elevation Drawing
C-300
EL-40' 0"
D-56
EL28' 0"
RX-105
EL 16' 0"
TK-105
TK-200
RX-106
equipment location. This information is important for making rounds, checking equipment, developing checklists, catching samples, and performing
startups and shutdowns.
Electrical Drawing
Electrical drawings (Figure 12.7) include symbols and diagrams that depict an electrical system. Electrical drawings show unit electricians where
power transmission lines run and places where power is stepped down or
up for operational purposes.
A process technician typically traces power to the unit from a motor control
center (MCC). The primary components of an electrical system are the
MCC, motors, transformers, breakers, fuses, switchgears, starters, and
switches. Specific safety rules are attached to the operation of electrical
systems. The primary safety system is the isolation of hazardous energy
“lock-out, tag-out.” Process technicians are required to have training in this
area. Figure 12.7 shows the basic symbols and flow path associated with
an electrical drawing. Electrical lines are typically run in cable trays to
switches, motors, ammeters, substations, and control rooms.
A transformer is a device used by industry to convert high voltage to low
voltage. The electric department always handles problems with transformers. Electric breakers are designed to interrupt current flow if design conditions are exceeded. Breakers are not switches and should not be turned on
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69,000 Volts
69 KV
MAIN
TRANSFORMER
V
As
A
51
Vs
27
Steam
Turbine
MCC #1
2.3 KV or
480 Volts
Motor
Starter
ELECTRIC POWER PLANT
Motor
Starter
M
M
Motor
Motor
V
Voltmeter: measures voltage
27
Under Voltage Relay
A
Ammeter: measures electric current
Vs
On
Off
MCC
Motor Control Center
Voltmeter Switch
Current Transformer: reduces high voltage to instrumentation.
As
Ammeter switch
50
Transformer Overcurrent Relay
(Instantaneous)
Potential Transforming Symbol
51
Transformer Overcurrent Relay
(Time delay)
Power Transformer: reduces high voltage
Circuit Breaker: a protective device
that interrupts current flow through an
electric circuit
Switch
Figure 12.7
260
Fuse
M
Electrical Drawing
13.2 KV
13.8 KV
2.3 KV
480V BUS MAIN POWER DISTRIBUTION
Generator
BOILER
13,200 V
13, 800 V
2,300 V
Motor Circuit Contacts
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or off. If a tripping problem occurs, the technician should call for an electrician. Fuses are devices designed to protect equipment from excess current. A thin strip of metal will melt if design specifications are exceeded.
During operational rounds, technicians check the ammeters inside the
MCC for current flow to their electrical systems. Voltmeters, electrical
devices used to monitor voltage in an electrical system, are also checked
during routine rounds.
Equipment Location Drawing
Equipment location drawings (plot plans) show the exact location of
equipment in relation to the plant’s physical boundaries (Figure 12.8). One
of the most difficult concepts to explain to a new process technician is the
scope and size of modern chemical processing. Most chemical plants and
refineries closely resemble small cities; they have well-defined blocks and
areas connected by a highway of piping and equipment. Equipment location drawings provide information about the neighborhood.
Loop Diagrams
A loop diagram traces all instrument connections between the field instrument and the control room panel. This includes instrument air lines, wiring
connections at field junction boxes, and control room panels and front
connections.
Electrical One-Line Diagrams
Like the piping in process systems, the wiring in a unit follows a path. Electrical diagrams show a flow path for distributing power throughout the unit and
TK-2
TK-3
TK-4
Figure 12.8
Equipment Location
8' 0"
TK-1
P-200
D-200
TK-100
18' 0"
TK-200
8' 0"
20' 0"
18' 0"
20' 0"
20' 0"
6' 0"
P-100
EX-200
P-500A
C-200
8' 0"
P-201
TK-300
EX-202
10' 0"
P-300
TK-400
P-400
20' 0"
16' 0"
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to all electrical equipment. These diagrams show the different voltage levels
in the unit, electrical equipment such as transformers, circuit breakers, fuses,
and motors and horsepower required. It also includes start/stop switches,
emergency circuits, and motor control centers. Process technicians can use
these diagrams to trace a system from the power source to the load.
Review of Basic and Specialized Symbols
Piping and Valves
Each plant will have a standardized file for their piping symbols. Process
technicians should carefully review the piping symbols for major and minor
flows; electric, pneumatic, capillary, and hydraulic elements; and future
equipment (Figure 12.9). The major flow path through a unit illustrates the
Figure 12.9
Piping Symbols
Y-type Strainer
RS
Removable Spool
Flexible Hose
Duplex Strainer
Expansion Joint
Basket Strainer
D
Detonation Arrestor
F
Flame Arrestor
S
In-Line Silencer
T
Steam Trap
XXX
Breather
Vent Cover
In-Line Mixer
Desuperheater
DS
Ejector / Eductor
S
Vent Silencer
Diverter Valve
Rotary Valve
Pulsation Dampener
Exhaust Head
Flange
Future Equipment
Major Process
Minor Process
LLL
262
Electromagnetic, Sonic
Optical, Nuclear
Electric
Connecting Line
Pneumatic
Non-Connecting Line
Hydraulic
Non-Connecting Line
X X
X X
Capillary Tubing
Jacketed or Double Containment
•
•
Mechanical Link
Software or Data Link
•
•
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Review of Basic and Specialized Symbols
critical areas a new technician should concentrate on. A variety of other
symbols are included on the piping. These include valves (Figure 12.10),
strainers, filters, flanges, spool pieces, insulation, piping size, pressure rating, material codes, and steam traps.
Pumps and Tanks
Pumps and tanks come in a variety of designs and shapes. Common pump
and tank symbols are shown on Figure 12.11.
Compressors, Steam Turbines, and Motors
Because compressors and pumps share a common set of operating principles and are classified as dynamic or positive displacement, the symbols for compressors may closely resemble those for pumps (compare
GATE VALVES
Manual
Operated
Valve
Gate
Valve
Pneumatic
GLOBE VALVES
Globe
Valve
Pneumatic
H
Motor
Hydraulic
M
H
Motor
Hydraulic
Bleeder
Valves
M
Angle
Needle
Pneumatic
BALL VALVES
Ball
M
Plug
Motor or
Hydraulic
BUTTERFLY VALVES
Butterfly
Motor
PLUG VALVES
H
Ball
Butterfly
Figure 12.10
Valves
M
Motor or
Hydraulic
Plug
M
Butterfly
S
DIAPHRAGM VALVES
Solenoid Valve
CLOSED
Pneumatic
Operated
Motor or
Hydraulic
CHECK VALVES
M
Diaphragm
SAFETY (Gases)
Motor
Check
Valve
RELIEF (Liquids)
Four-Way
Check
Valve
Stop Check
Three-Way
Valve
Relief
Valve
Knife Valve
Pinch Valve
Gauge
Rotameter
Orifice
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CENTRIFUGAL PUMPS
POSITIVE DISPLACEMENT PUMPS
Positive
Displacement
Positive Displacement
Vertical
Progressive Cavity
Horizontal
Gear
Pump
Screw Pump
Vertical
Screw Pump
Sump Pump
Vertical
Vertical Can
Pump
Vacuum Pump
Reciprocating Pump
STORAGE SYMBOLS
Dome Roof
Tank
Bin
Open Top
Tank
Tank
Tank
Double Wall
Tank
Cone Roof
Tank
Drum
Sphere
Figure 12.11
Internal Floating
Roof Tank
Onion Tank
External Floating
Roof
Pumps and Tanks
Figures 12.11 and 12.12). In most cases, the compressor symbol is slightly
larger than the pump symbol.
In the multistage, centrifugal compressors, the narrowing of the symbol from
left to right denotes compression of the gas before it is released. This is in
sharp contrast to the steam turbine symbol, which illustrates the opposite effect as the steam expands while passing over the rotor. Modern P&IDs show
the motor symbol connected to the driven equipment. This equipment may
be a pump, compressor, mixer, or generator. Figure 12.12 illustrates the
standardized symbols for compressors, steam turbines, and motors.
Heat Exchangers and Cooling Towers
Heat exchangers and cooling towers are two types of industrial equipment
that share a unique relationship. A heat exchanger is a device used to
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CENTRIFUGAL COMPRESSORS
PD COMPRESSORS
T
Centrifugal
Compressor
Centrifugal Compressor
(Turbine Driven)
Centrifugal
Compressor
Centrifugal
Blower
Reciprocating
Compressor
Rotary
Compressor
Rotory
Compressor
& Silencers
Rotary Screw
Compressor
Liquid Ring
Vacuum
Positive
Displacement
Blower
Reciprocating Compressor
Axial Compressor
STEAM TURBINE
MOTORS
Agitator or Mixer
Turbine Driver
Doubleflow Turbine
Motor
Diesel Motor
Figure 12.12
Compressors, Steam Turbines, and Motors
transfer heat energy between two process flows. The cooling tower performs a similar function, but cooling towers and heat exchangers use different scientific principles to operate. Heat exchangers transfer heat energy
through conductive and convective heat transfer, whereas cooling towers
transfer heat energy to the outside air through the principle of evaporation.
Figures 12.13 and 12.14 illustrate the standard symbols used for heat
exchangers and cooling towers.
The symbol for a heat exchanger clearly illustrates the flows through
the device. It is important for a process technician to be able to recognize the shell inlet and outlet and the tube inlet and outlet flow paths. A
heat exchanger with an arrow drawn through the body illustrates
whether the tubeside flow is being used to heat or cool the shellside
fluid. The downward direction indicates heating; the upward direction illustrates cooling.
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Figure 12.13
Heat Exchangers
Plate and Frame
Heat Exchanger
Hairpin Exchanger
Air Cooled Exchanger
(Louvers Optional)
Double-Pipe
Heat Exchanger
U-Tube
Heat Exchanger
Single Pass
Heat Exchanger
C
C
Spiral Heat Exchanger
Heater
Condenser
Shell and Tube Heat Exchanger
Figure 12.14
Cooling Towers
INDUCED DRAFT
Crossflow
HYPERBOLIC
Chimney Tower
266
Reboiler
FORCED DRAFT
Counterflow
NATURAL DRAFT
Counterflow
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Figure 12.15
Furnace and Boiler
Furnace
Boiler
The symbol for a cooling tower is designed to resemble the actual device
in the process unit. Cooled product flows out of the bottom of the tower and
to the processing units. Hot water returns to a point located above the fill.
The symbol will not show all of the various components of the cooling tower
system, but it will provide a technician with a good foundation in cooling
tower operation and enough information to clearly see the process.
Furnaces and Boilers
The standard symbols file for furnaces and boilers is shown in Figure 12.15. If a proprietary process includes several types of equipment not
typically found on a standard symbol file, the designer will draw the device
as it visually appears in the unit.
Distillation Columns
Distillation columns come in two basic designs, plate and packed (Figure 12.16). Flow arrangements vary from process to process. The symbols allow the technician to identify primary and secondary flow paths.
Distillation is a process designed to separate the various components in
a mixture by their boiling points. (See Chapter 15.) A distillation column is
the central component of a much larger system. This system typically includes all of the equipment symbols found in this chapter. Plate distillation
columns include sieve trays, valve trays, and bubble-cap trays. Packed
columns are filled with packing material, rings, saddles, sulzer, and
rosette.
Reactors
Reactors (Figure 12.17) are stationary vessels and can be classified as
batch, semibatch, or continuous. A reactor is designed to allow chemicals to mix together under specific conditions to make chemical bonds,
break chemical bonds, or make and break chemical bonds to form new
products.
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Figure 12.16
Distillation Symbols
PLATE TOWER
Bubble-cap, Sieve, Valve
PACKED TOWER
Saddle, Ring, Sulzer, Rosette
Single Pass
Demister
Spray Nozzle
Chimney
Two Pass
Packed Section
Draw Off
Generic Tray
Manway
Vortex Breaker
Sources of Information
for Process Technicians
Information used by process technicians comes from a variety of sources.
Some of these sources are:
• Operating training manuals
• Process descriptions
• Process control manuals
• Equipment summaries
• Safety, health, and environment regulations
• Operating procedures
• Startup and shutdown procedures
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Summary
Figure 12.17
Reactor Symbols
Hydrocracking
Fluid Catalytic
Cracking
Hydrodesulfurization
Fluid Coking
Mixing Reactor
•
•
•
•
Tubular
Reactor
Reformer
Fluidized
Reactor
Alkylation
Emergency procedures
Process diagrams
Technical data books
Detailed equipment vendor information
Summary
Process flow diagrams (PFDs) and process and instrument drawings
(P&IDs) are used to outline or explain the complex flows, equipment, instrumentation, electronics, elevations, and foundations that exist in a
process unit. A PFD is a simple flow diagram that describes the primary
flow path through a unit. A P&ID is a complex representation of the various
units found in a plant. Standardized symbols and diagrams have been
developed for most pieces of industrial equipment, process flows, and
instrumentation.
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Chapter 12
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Process Diagrams
Review Questions
1. Describe a process flow diagram and a process and instrument drawing.
2. Draw the symbols for a gate, globe, and automatic valve.
3. Draw the symbols for a centrifugal pump and positive displacement pump.
4. Draw the symbols for a blower and a reciprocating compressor.
5. Draw the symbols for a steam turbine and centrifugal compressor.
6. Draw the symbols for a heat exchanger and a cooling tower.
7. Draw the symbols for a packed distillation column and plate distillation column.
8. Draw the symbols for a furnace and a boiler.
9. Draw a simple process flow diagram using the symbols from questions 2–8.
10. What information is obtained from a loop diagram?
11. What information is available on electrical one-line diagrams?
12. What information is contained on a plot plan drawing?
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