Chemical Engineering May 2016 - 17

Avoiding abnormal events
Another approach for reducing process-operator errors
discussed at the AFPM meeting focuses on predicting
process faults more effectively to avoid abnormal process
events. Thomas kindervater, the solution support
manager at the Center for Operator Performance (COP;
Dayton, Ohio; www.operatorperformance.org), explained
that while process faults are a significant concern in the
chemical and petrochemical industries, the real problem
is that " process operators typically become aware of process
faults only after the problem has triggered an operating
alarm, forcing the operator to react to the situation
after it has caused a deviation of the process from desired
operating conditions. " The better alternative would be for
the operator to proactively address a process fault before
it causes an operational deviation that is sufficient to trigger
an alarm, kindervater said.
kindervater discussed research commissioned by the
COP and conducted by Michael Baldea and Ray Wang
at the University of Texas at Austin (www.utexas.edu)
that aimed to help identify ways to provide operators
with advanced warning of pending abnormal events.
The research developed a new fault-detection approach
that employs geometric analysis of time-ordered radial
plots. Radial plots depict multi-variable data samples
using axes extending outward from a central point, while
the time dimension is represented by stacking the data
samples (Figure 1). The tool developed by the research
group performed better than several other widely used
data-analysis techniques, kindervater said, with a very
low rate of false positives.
The technique has been successfully applied in the
detection of surge in a large, multistage compressor,
where analysis of past surges helped identify event
signatures as early as a few hours before surge onset,
kindervater explained. It has given equally impressive
fault detection for distillation flooding events and for detecting
precursors to flaring events, continuing to show
a low false-positive rate, he says.
Alkylation technology advances
Meanwhile, within another session on gasoline production,
AFPM attendees heard about progress on several
unique alkylation installations.
Several presentations emphasized the rising imporPI
8
WASH
WATER
(FROM BLEED PUMP)
3 "
tance of alkylation processes, which involve combining
light olefins with isobutane to produce isomers of trimethylpentane,
a liquid hydrocarbon known as alkylate
that is used as a clean gasoline blendstock. Alkylate is a
premium gasoline component because it provides high
octane, low Reid vapor pressure, low sulfur and no aromatic
compounds. The demand for alkylate is growing
primarily as a result of gasoline demand from emerging
economies, tighter government-mandated gasoline
specifications, removal of high-octane components
(such as aromatics and olefins) from the gasoline pool
and higher-performance engine requirements.
Tightening restrictions on sulfur content in gasoline
requires a greater level of hydrotreating, which reduces
DPI
1
4 " SPARE
PI
8
PT
8
PT
2
MIST ELIM.
WASH WATER
MANWAY
3 "
PI
2
75,000 GAL MAX. CAPACITY
DPI
1
DPT
1
Call us: (973) 947-8787
Email us: info@crcleanair.com
Address: Six Campus Drive
Parsippany, NJ 07054
AI
PT
1
PI
1
TE
4
TE
2
3/4 "
IMMERSION HEATER
LIQUID SEPARATOR TANK
96 " Ø x 10' TALL
1st JET
AI
2
1
6 "
T I
4
T I
2
pH
pH
pH
AI
1
36 " GAS INLET
FAL
1
FT
1
11
2 "
FE
1
Circle 39 on p. 94 or go to adlinks.chemengonline.com/61495-39
12 " GAS INLET
Visit us at: www.CRCleanAir.com
1st JET
3 3
1 1
6 "
RECYCLE
PUMP A
TIC
2
CAUSTIC FILL
(FROM CHEM. STORAGE TANK)
MAG
TE
TE
TIT
TIT
4 "
4 "
4 "
3/4 "
FAL
1
104A
AI
DPT
1
PACKING
50 GAL. CAPACITY
1st JET
IMMERSION HEATER
36 " GAS INLET
(EMERGENCY)
12 " GAS INLET
ACID STORAGE TANK
(NORMAL)
AI
104B
ORP
H2SO5
METERING PUMP (STAND-BY)
PT
7
PI
7
4 "
AI
AI
4
3
PT
4
OR
OR
3/4 "
4 "
4 "
2 "
METERING PUMP (OPERATING)
ORP
1st JET H2SO4
FT
1
FE
1
NEUTRALIZATOIN TANK
1200 GAL. CAPACITY
MAG
TE
TIT
3 3
1 1
IMMERSION HE
TE
TIT
PT
8
PT
2
MIST ELIM.
LIQUID EFFLUENT
PI
2
PT
1
LEADERS IN CLEAN AIR TECHNOLOGY
When it has to work.
Th e first time...
every time.
From Arsenic to Zirconium Tetrachloride...
we scrub gasses others won't touch!
INDUSTRIES
Aerospace
Agriculture
Chemical
Cement
Fertilizer
Fibers
Food
HVAC
Medical
Petrochemical
Pharmaceutical
Pulp & Paper
Semiconductor
Textile
LIQUID EFFLUENT
(FROM BLEED PUMP)
NEUTRALIZ
1200 GAL
TANK FARM
50 GAL. CAPACITY
IMMERSION HEATER
METERING PUMP (OPERATING)
ACID STORAGE TANK
CHEMCIAL ADDITION PUMP (OPERATING)
AI
105A
AI
104B
ORP
500 GAL. CAPACITY
H2SO5
105B
AI
ORP
TO CAUSTIC FILL
NAOH
CHERMICAL ADDITION PUMP (STAND-BY)
METERING PUMP (STAND-BY)
IMMERSION HEATER
ORP
NAOH STORAGE
ORP
104A
AI
I
H2SO4
TO CAUSTIC FILL
NAOH
TANK FARM
POLLUTANTS
HCL / CL2
HF / HBr
SO2
NH3
NOx
H2S
105B
AI
ORP
CHERMICAL ADDITION PUMP (STAND-BY)
ETO / PO
SiO2
SiCL3
Mists
Dust
Particulate
Phosgene
VOC's
CHEMCIAL ADDITION PUMP (OPERATING)
AI
105A
ORP
NAOH STORAGE
500 GAL. CAPACITY
IMMERSION HEATER
PI
1
TIC
1
PT
5
BY-PASS
http://www.operatorperformance.org http://www.utexas.edu http://www.CRCleanAir.com http://adlinks.chemengonline.com/61495-39
Chemical Engineering May 2016

Table of Contents for the Digital Edition of Chemical Engineering May 2016
