Process Operability Class Materials
Process Monitoring
Basic flowsheet
LAH
LAL
Design with Operability
L
2
LC
1
LC
1
FC
1
FC
1
TC
2
TC
1
F
4
fuel
T
10
T
12
T
13
Copyright © Thomas Marlin 2013
The copyright holder provides a royalty-free license for use of this material at non-profit
educational institutions
T
11
Key Operability
issues
1. Operating
window
2. Flexibility/
controllability
MONITORING AND DIAGNOSIS
To perform monitoring and diagnosis, people need
information.
Sensor Issues (a little review)
3. Reliability
Real-time Decisions*
4. Safety &
equipment
protection
•
Trouble shoot incidents using proven method
Real-time
sensors
•
Information to support decisions required
quickly
Fast lab
analyses
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
Process Performance Improvement
•
•
Longer term performance indicators based
on data and calculations
Usually identifying slow trends
* See trouble shooting lesson for more on strategy and examples
Sensors for
calculations
Lab analysis
Data for
statistical
analysis
Sensors
Key Operability
issues
MONITORING AND DIAGNOSIS
Sensors
1. Operating
window
2. Flexibility/
controllability
3. Reliability
4. Safety &
equipment
protection
Selecting sensor technology
•
Achieve required accuracy and reproducibility
•
Achieve required reliability
- Functions well for range of process environments
- Protect from damage (e.g., thermowell) or sample
from process and measure in less harsh conditions
- Redundancy, if required
- Redundancy with diversity, if required
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
•
Provide means for calibration and maintenance
•
Balance cost (capital,maintenance and operating)
with benefit to achieve economic return
8. Monitoring &
diagnosis
http://www.pc-education.mcmaster.ca/instrumentation/go_inst.htm (Select 2.0 Sensors)
Sensors
Key Operability
issues
1. Operating
window
MONITORING AND DIAGNOSIS
Sensors
2. Flexibility/
controllability
analysis
all other
level
3. Reliability
4. Safety &
equipment
protection
Sensors used for
plant control
flow
temperature
pressure
5. Efficiency &
profitability
all other
flow
analysis
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
Sensors used
for plant
display and
monitoring
level
pressure
temperature
Higham, E.H., A Route to Better Process Measurements, I.Chem.E. Hazards X - Process Safety in Fine
Chemical and Specialty Plants, 1989. (Current practice might include more on-stream analysis.)
Sensors
Key Operability
issues
1. Operating
window
2. Flexibility/
controllability
3. Reliability
4. Safety &
equipment
protection
MONITORING AND DIAGNOSIS
Sensors
Class exercise on sensors
You have been asked to evaluate the performance of a process.
You will use all forms of data, from trend to historical reports.
What are some of the questions that you might to ensure that
you interpret the sensor data correctly?
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
Why should I ask questions?
Every data value is exact, at least to the
number of significant figures on the plot
or in the numerical display!
Sensors
Key Operability
issues
MONITORING AND DIAGNOSIS
Process Performance Improvements
1. Operating
window
2. Flexibility/
controllability
Class exercise: a. Sensor range
3. Reliability
1.
Most sensor accuracies depend on the range (or span). A
sensor with a range of 1000 K has a poorer accuracy than
one with a range of 100 K.
2.
Some sensor accuracies depend on the position in the range.
For example, an orifice meter has a very poor accuracy at
10% of maximum range.
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
Also, a flow meter can report a very small value when the
flow is actually zero.
3.
If the measured value equals the maximum (minimum) of the
range, the plant value could be much higher (lower) than the
reported value.
Sensors
Key Operability
issues
MONITORING AND DIAGNOSIS
Process Performance Improvements
1. Operating
window
2. Flexibility/
controllability
Class exercise: b. Sensor Technology
3. Reliability
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
1.
Different sensors for the same process variable (P, T, F,
L, etc) can have very different accuracies. For example,
a RTD is much more accurate that a thermocouple.
2.
Different sensor technologies are robust (sensitive) to
changes in process conditions,such as suspended solids
in a flowing fluid. This knowledge helps in anticipating
potential sensor problems, sensor loss of accuracy and
in trouble shooting process operation.
Sensors
Key Operability
issues
1. Operating
window
2. Flexibility/
controllability
3. Reliability
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
MONITORING AND DIAGNOSIS
Process Performance Improvements
Class exercise: c. Measurement compensation. Several
measurements can be used to provide a more accurate value
for a single process variable.
Orifice flow meters relate the pressure change across the
orifice to the flow rate. The relationship depends on the
fluid density. Either the density or gas pressure and
temperature can be used to correct for changes for an
assumed (design) value. You need to know whether or not
this correction has been performed.
Is this measured and used in the
calculation, or is the value assumed
constant (at the design value?)
Real-time
Key Operability
issues
MONITORING AND DIAGNOSIS
Real-time Decisions
1. Operating
window
2. Flexibility/
controllability
3. Reliability
4. Safety &
equipment
protection
We have learned the importance of measurements in
trouble shooting.
•
During process design, we need to brainstorm a list of likely
faults that will require trouble shooting
•
Faults in sensors are expected and can easily mislead
personnel. Select reliable sensors that match process
environment and add redundancy where appropriate.
•
For each, the diagnosis procedure can be documented (and
used for training and manual writing). Fishbone diagrams
aid the thought process and documentation.
•
We need to ensure that the required measurements (sensors
and laboratory) are provided to support successful trouble
shooting!
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
Real-time
Key Operability
issues
MONITORING AND DIAGNOSIS
Real-time Decisions
1. Operating
window
2. Flexibility/
controllability
We select measurements based on an analysis of
design goals and possible incidents
3. Reliability
Significant
Incident # 3
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
•
Safety
•
Equipment
damage
Root cause 1
Root cause 2
•
•
•
Environmental
impact
•
•
Product quality
•
•
Production rate
•
•
Profitability
Root cause n
Select measurements that enable operations personnel to uniquely
determine the most likely root causes of every significant incident.
Real-time
Key Operability
issues
MONITORING AND DIAGNOSIS
Real-time Decisions
1. Operating
window
Balancing Function and Cost – Location of sensors
2. Flexibility/
controllability
3. Reliability
4. Safety &
equipment
protection
Control room Displayed & Automatic Control
7. Dynamic
Performance
8. Monitoring &
diagnosis
1
•
The variable is required to achieve one of the control
objectives for the process.
•
Necessary information for the controller can be measured.
Variable should be monitored reliably and rapidly.
•
Rapid and reliable feedback is required.
•
Automated action may be discrete or continuous.
•
Manipulated variable can be adjusted automatically
•
Stored in computer history and available on trend plot
•
All of above applies to safety shutdown as well as modulating
control.
5. Efficiency &
profitability
6. Operation
during
transitions
TC
Real-time
Key Operability
issues
MONITORING AND DIAGNOSIS
Real-time Decisions
1. Operating
window
2. Flexibility/
controllability
Balancing Function and Cost – Locations of sensors
3. Reliability
Control room Displayed
T
2
4. Safety &
equipment
protection
•
Variable need not be controlled automatically; can be
used to monitor process/equipment performance
5. Efficiency &
profitability
•
If controlled, slowly by operator action is acceptable
6. Operation
during
transitions
•
If controlled, manipulated variable adjusted from
control room (“manual” station to change valve %
open or motor on/off)
•
Stored in computer history and available on trend
plot
7. Dynamic
Performance
8. Monitoring &
diagnosis
Real-time
Key Operability
issues
MONITORING AND DIAGNOSIS
Real-time Decisions
1. Operating
window
Balancing Function and Cost – Location of sensors
2. Flexibility/
controllability
Locally Displayed
3. Reliability
4. Safety &
equipment
protection
5. Efficiency &
profitability
3
•
Variable need not be controlled; can be used to
monitor process/equipment performance
•
Operator must travel to unit to observe the display
•
Used to monitor slowly changing process/equipment
performance, for example, heat exchanger fouling
and pressure drops in packed beds
•
Can be used for trouble shooting when rapid response
is not required
•
Not stored in computer history - can be recorded on
written log very infrequently (1/shift or day)
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
T
Real-time
Key Operability
issues
1. Operating
window
2. Flexibility/
controllability
MONITORING AND DIAGNOSIS
Real-time Decisions
Real-time data is used to determine the “health” of
the process. Use your process knowledge!
3. Reliability
For a chemical reaction with
a significant heat of reaction
(endo- or exothermic), the
temperature change across
the reactor provides an
inference of the extent of
reaction.
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
Hydrocracker
reactions are
highly
exothermic
Runaway is
possible.
Very useful, especially when
on-stream analysis is not
practical
Real-time
Key Operability
issues
MONITORING AND DIAGNOSIS
Real-time Decisions
1. Operating
window
2. Flexibility/
controllability
Real-time data is used to determine the “health” of
the process. Use your process knowledge!
3. Reliability
4. Safety &
equipment
protection
For semi-batch (batch-fed) bio-reactor, the off-gas flow rate and composition can
be used to monitor the “health” of the reaction system – should the batch
continue to completion or be aborted?
PC
5. Efficiency &
profitability
TC
FC
6. Operation
during
transitions
fo
fc
Gas produced by the
biological process
L
fo
7. Dynamic
Performance
8. Monitoring &
diagnosis
CW
fo
Real-time
Key Operability
issues
1. Operating
window
2. Flexibility/
controllability
MONITORING AND DIAGNOSIS
Real-time Decisions
Real-time data is used to determine the “health” of
process equipment. Use your knowledge of equipment.
3. Reliability
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
• Used for monitoring,
display, and alarms to
personnel
• Used for SIS for
safety and equipment
protection
Monitoring rotating equipment can include
• Vibration
• Temperature
• Flow
• Lubrication pressure
• Power consumption
• Equipment
manufacturers often
provide monitoring
Turbine
T. Reeves, EPTQ, Q3, 2005 (www.eptq.com)
Compressor
Real-time
Key Operability
issues
1. Operating
window
2. Flexibility/
controllability
MONITORING AND DIAGNOSIS
Real-time Decisions
Real-time data is used to determine the “health” of
process equipment. Use your knowledge of equipment.
3. Reliability
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
In a chemical reactor, poor flow
distribution can lead to “hot
spots” that can damage catalyst
or even the reactor vessel.
Locating many temperature
sensors at various locations in
the bed provides monitoring for
poor flow distribution.
Used for monitoring, alarms and
control.
Real-time
Key Operability
issues
1. Operating
window
2. Flexibility/
controllability
3. Reliability
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
MONITORING AND DIAGNOSIS
Real-time Decisions
We need information for process troubleshooting. Remember
that people are the ultimate backup protection; they have to
correct for equipment malfunctions.
Class Workshop: Add the sensors
required to monitor this distillation
tower in real time.
Hints:
• What limits must not be violated?
• What incidents must we diagnose?
• What equipment can fail?
• What redundancy is needed?
• Where should display be located?
FR
FV
Real-time
Key Operability
issues
1. Operating
window
2. Flexibility/
controllability
MONITORING AND DIAGNOSIS
Real-time Decisions
Class Workshop: Add the sensors required to monitor this distillation tower
in real time.
3. Reliability
Some thoughts:
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
• pressure of closed vessel is very important
• levels in the accumulators are unstable
• trays can leak liquid to lower trays
• trays can become blocked
• internal flows can exceed hydraulic limits
• utility streams are important (e.g., steam)
• the composition of trays should have an expected profile
• pumps can malfunction
• cooling water temperature should be below maximum limit
Real-time
Key Operability
issues
MONITORING AND DIAGNOSIS
Real-time Decisions
1. Operating
window
To flare
T
29
PAH
2. Flexibility/
controllability
T
30
PC-1
PV-3
Do we need to
increase the
capital costs with
all theses sensors?
L4
P3
T5
3. Reliability
P
12
P
20
4. Safety &
equipment
protection
LAH
LAL
LC-1
17
FC
7
16
Plus maintenance!
dP-1
F
30
15
T6
5. Efficiency &
profitability
AC
1
P
21
T10
3
TC
7
6. Operation
during
transitions
T20
FC
4
2
dP-2
1
P
11
7. Dynamic
Performance
T
44
T
22
LC
3
LAH
LAL
F9
FC
8
8. Monitoring &
diagnosis
YES !!
T
45
P
23
Longer term
Key Operability
issues
1. Operating
window
2. Flexibility/
controllability
3. Reliability
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
MONITORING AND DIAGNOSIS
Process Performance Improvements
• Many features of a process change slowly, over
days, weeks or months
• The performance of complex systems is often
not obvious from direct observation of the
data
• Engineers can identify key process
performance measures that can be calculated
automatically and stored in history
• Actions are based on careful analysis of the
data and might require either minor changes
or extensive plant changes, during shutdowns
Longer term
Key Operability
issues
MONITORING AND DIAGNOSIS
Process Performance Improvements
1. Operating
window
2. Flexibility/
controllability
3. Reliability
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
Often, several measurements are used to calculate a
key process variable from a complex process.
Examples of performance measures are:
•
•
•
•
•
7. Dynamic
Performance
•
8. Monitoring &
diagnosis
Yields from a reactor
Electricity consumption per kg feed
Total effluent (of water, sulfur, etc.)
Efficiency of equipment (turbine, compressor,
fired heater, etc.)
Operating conditions for successful and
unsuccessful batches
Inventory in plant (work in progress, feed,
and finished products)
Longer term
Key Operability
issues
MONITORING AND DIAGNOSIS
Process Performance Improvements
1. Operating
window
2. Flexibility/
controllability
3. Reliability
4. Safety &
equipment
protection
Engineers must understand the sensors used and
the methods for data storage before deciding how to
use the measurement data.
•
Each sensor has a physical principle
affecting its accuracy and reproducibility
•
Data is stored in a history data base, but
some information is lost
•
Some actions by people are also recorded
•
Sometimes, measurement and computing
equipment fail
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
Longer term
Key Operability
issues
MONITORING AND DIAGNOSIS
Process Performance Improvements
1. Operating
window
2. Flexibility/
controllability
History data
base
3. Reliability
Display
Exercise: What
questions would
we like to answer
using the
history data base?
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
The historical data base typically contains
1.
2.
3.
4.
5.
Sensor measured values
Events: Alarms, set point changes, controller mode and
tuning changes, SIS activation
Calculated variables (defined and build by engineer)
Cause of SIS activation
Laboratory analysis
Longer term
Key Operability
issues
MONITORING AND DIAGNOSIS
Process Performance Improvements
1. Operating
window
History
data base
2. Flexibility/
controllability
Display
3. Reliability
4. Safety &
equipment
protection
Some typical questions answered using the historical data base
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
•
•
•
•
•
•
How much feed did we process last week?
What was the yield of vinyl chloride monomer?
How much energy was consumed per 1000 kg of product?
What was the total release of sulfur from the plant last
month?
What was the distribution of product quality, displayed as a
histogram?
How much valuable hydrogen was diverted to fuel gas last
week?
Longer term
Key Operability
issues
1. Operating
window
MONITORING AND DIAGNOSIS
Process Performance Improvements
2. Flexibility/
controllability
3. Reliability
4. Safety &
equipment
protection
Storing ½ second data for 1000 measurements for 30
years is a lot of data!
1000 x 120 x 60 x 24 x 365 x 30  2 x 1012
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
Therefore, the data base has several layers with data
aggregated to reduce storage. While storage capacity
and computer speeds will continue to increase, the
basic design will likely persist for a long time because
we don’t need every data point for many analyses.
MONITORING AND DIAGNOSIS
Process Performance Improvements
Sampling periods and storage duration
tailored to need. For example, SIS period is
very fast (milliseconds) to diagnose fault.
Special purpose
systems
Aggregation: Large amounts of data stored
for long times. Data is taken periodically
with long sampling periods, e.g., 5 minutes.
Historian
Data is stored with decreasing resolution,
e.g., 3 days of 1/min, 7 days of 1/hr, 30
days 1/day
Trend plots are updated 1/sec for new data,
but this high-frequency data is not stored for
later recall.
DCS control
system
Longer term
Key Operability
issues
MONITORING AND DIAGNOSIS
Process Performance Improvements
1. Operating
window
2. Flexibility/
controllability
3. Reliability
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
Some typical ways to aggregate a variable
•
Average (shift, daily, weekly, monthly)
•
Integration, e.g., total flow per day (for material or
energy)
•
Maximum and minimum over a period
•
Standard deviation (or histogram)
•
Analysis can have multiple values
To aggregate several variables, use process insight
7. Dynamic
Performance
8. Monitoring &
diagnosis
•
Calculate key process performance measures (efficiencies,
yields, etc.)
Longer term
Key Operability
issues
1. Operating
window
2. Flexibility/
controllability
MONITORING AND DIAGNOSIS
Process Performance Improvements
History
data base
3. Reliability
Display
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
Class Exercise: Occasionally, a sensor fails or the
history storage fails for a period of time.
How does the aggregation method handle these
situations?
Longer term
Key Operability
issues
MONITORING AND DIAGNOSIS
Process Performance Improvements
1. Operating
window
History
data base
2. Flexibility/
controllability
Display
3. Reliability
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
Class exercise: Periods when a reliable value is not
available is marked questionable.
1.
Reports should provide information on whether any data
within the aggregation period was questionable. (Best if % of
data that is questionable reported)
2.
You need to determine how the algorithm deals with missing
data (ignore, interpolate, use last good before, use first good
after, etc.) when calculating results, such as average or total.
Longer term
Key Operability
issues
1. Operating
window
2. Flexibility/
controllability
MONITORING AND DIAGNOSIS
Process Performance Improvements
History
data base
3. Reliability
Display
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
Plant personnel also check local sensors
periodically (per shift or day) and record values.
This data can be stored on paper, or the values can
be entered into a hand-held computer and
transferred to the history data base.
Longer term
Key Operability
issues
1. Operating
window
2. Flexibility/
controllability
MONITORING AND DIAGNOSIS
Process Performance Improvements
History
data base
3. Reliability
Display
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
Plant personnel extract samples of material for
laboratory analysis.
This data can be stored on paper, or the values can
be entered into the history data base.
The time the sample was taken is essential
information.
Longer term
Key Operability
issues
MONITORING AND DIAGNOSIS
Process Performance Improvements
1. Operating
window
2. Flexibility/
controllability
3. Reliability
4. Safety &
equipment
protection
Class Exercise: The data changes from sample to
sample. How do we determine when a “significant”
change has occurred?
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
Key process variable,
e.g., Product quality
5. Efficiency &
profitability







  
Time 







Desired value
Longer term
Key Operability
issues
MONITORING AND DIAGNOSIS
Process Performance Improvements
1. Operating
window
2. Flexibility/
controllability
3. Reliability
4. Safety &
equipment
protection
We can use principles of statistical process control
(SPC) to monitor and decide when a significant change
has occurred.
Process personnel trouble shoot, diagnose and
eliminate the cause
5. Efficiency &
profitability
7. Dynamic
Performance
8. Monitoring &
diagnosis
Key process variable,
e.g., Product quality
6. Operation
during
transitions
“Shewhart Chart”
Action limit











Action limit
Time 



 

Desired value
Longer term
Key Operability
issues
MONITORING AND DIAGNOSIS
Process Performance Improvements
1. Operating
window
Class Workshop: In your first job, you are responsible for the
heat exchangers and fired heater in this process. Design a
monitoring procedure (with sensors and lab analyses).
2. Flexibility/
controllability
3. Reliability
Heat exchange with process streams that must be cooled.
4. Safety &
equipment
protection
feed
tank
5. Efficiency &
profitability
6. Operation
during
transitions
fuel
Hints:
7. Dynamic
Performance
8. Monitoring &
diagnosis
•
What can change?
•
Is it important for plant performance?
•
How does it affect measurements?
•
Define measurements and calculations.
product
Longer term
Key Operability
issues
1. Operating
window
MONITORING AND DIAGNOSIS
Process Performance Improvements
2. Flexibility/
controllability
3. Reliability
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
Class Workshop: In your first job, you are responsible for the
reactor (and catalyst regenerator) in the process shown on the
next slide. Design a monitoring procedure (with sensors and lab
analyses).
Hints:
• What can change?
• Is it important for plant performance?
• How does it affect measurements? Include laboratory samples
for variables that might not be measured on-stream.
• Define measurements and calculations.
Longer term
COMPRESSOR
OVERHEAD CONDENSER/ACCUMULATOR
HIGH PRESSURE
CONDENSER/
SEPARATER
Hints:
•
What can change?
•
Is it important for plant
performance?
•
•
ABSORBER
TAIL
GAS
How does it affect measurements?
SPONGE
OIL
ABSORBER
TOP
P.A.
DEETHANIZER
LCGO
P.A.
Define measurements and
calculations.
HCGO P/A
LCGO
STRIPPER
BPA P/A
RAW
GASOLINE
ABSORBER
MAIN
FRACTIONATOR
REACTOR PRODUCTS
C4'S
DEPROPANIZER
HCGO
P.A.
C3'S
LCGO
REACTOR
EFFLUENT
FLUE GAS
STEAM
BOTTOM
P.A.
DEBUTANIZER
LCPA P/A
BPA P/A
HCGO
STEAM
AIR
STEAM
FRESH FEED
FULL RANGE
CAT NAPHTHA
Longer term
Key Operability
issues
1. Operating
window
2. Flexibility/
controllability
3. Reliability
4. Safety &
equipment
protection
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
MONITORING AND DIAGNOSIS
Real-Time & Process Performance
Improvements
INDUSTRIAL PRACTICE
• Standard measurement choices have been
developed for most unit operations.
• Some issues require advanced analysis, for
example, pipeline leak detection, rotating
machinery vibration, pump alignment/lubrication,
compressor surge, etc.
• Process performance monitoring has not been
comprehensively studied. Opportunity exists for
innovation, especially using statistical correlation
to distinguish good/bad.
Key Operability
issues
1. Operating
window
2. Flexibility/
controllability
MONITORING AND DIAGNOSIS
To perform monitoring and diagnosis, people need
information.
Sensor Issues (a little review)
3. Reliability
Real-time Decisions*
4. Safety &
equipment
protection
•
Trouble shoot incidents using proven method
Real-time
sensors
•
Information to support decisions required
quickly
Fast lab
analyses
5. Efficiency &
profitability
6. Operation
during
transitions
7. Dynamic
Performance
8. Monitoring &
diagnosis
Process Performance Improvement
•
•
Longer term performance indicators based
on data and calculations
Usually identifying slow trends
* See trouble shooting lesson for more on strategy and examples
Sensors for
calculations
Lab analysis
Data for
statistical
analysis