Hydrocarbon Processing - December 2020 - 65
Process Optimization
Option 3, the reduction is the highest
among all DWC options (47%).
It should be noted that the packing volume required for columns does not solely
depend on the number of theoretical stages, and the column diameter must be considered for its calculation. As explained
previously, in deep vacuum applications,
volumetric gas flowrate changes drastically with the operating pressure of columns,
which has a direct impact on column diameter. The resulting packing volume required for each option is listed in TABLE 3.
For DWC Option 1, the packing volume required is slightly smaller than the
one required by the conventional route,
whereas the required packing volume increases by 25% for DWC Option 2. The
largest volume is required for DWC Option 3; the percentage of packing volume
increase reaches 38%, even though the
overall number of theoretical stages is reduced by 47%.
It should also be noted that packing
volume is just one way to look at capital
cost. A holistic assessment is provided by
estimating the inside battery limits costs,
which include the costs of pressure vessels, heat exchangers, piping and valves,
pumps, etc. Estimations on the relative
cost savings for the inside battery limits
for the PFKA distillation plant are listed
in TABLE 3 for each DWC option. Equivalently important for the economic viability of a project is the reduced plot area for
all DWC options. Plot area and reduced
CAPEX can easily outweigh the disadvantages associated with increased packing volumes for DWC Options 2 and 3.
Last but not least, whether an option
is commercially viable also depends on
the availability of utilities in a particular
plant and the possibility of heat recovery
and integration. In fatty acid fractionation, the temperature of some process
fluids flowing inside condensers is sufficiently high; therefore, the latent heat
is usually recovered by generating a lowpressure stream that can be a further reused source of energy.
Conclusions. This article presents a con-
ceptual study of various DWC options for
distillation of fatty acids using a typical
PKFA feed composition. The results of
this study show the benefits in terms of
both operational and capital costs compared to a conventional plant design.
Due to extensive industrial references
C8-C10
C16
C12-C14
C8-C10
C8-C10
C12-C14
C12-C14
Feed
C16
Feed
Feed
C16
DWC 1
C3
DWC 2
DWC 3
C18+
C18+
C18+
FIG. 3. Various DWC options.
TABLE 3. Relative packing volume and relative inside battery limits costs for each
DWC option
Option
Column
Conventional route
C1
C2
C3
DWC1
DWC1
DWC2
C3
C1
DWC2
DWC3
DWC3
Total packing
volume
Reference
-5%
+25%
+38%
Total ISBL
Reference
-15 ± 2%
-10 ± 2%
-17 ± 2%
of similar configurations in other applications, the DWCs with one partition wall
are commercially viable. Despite the significant technical advantages, a DWC
with three partition walls remains a theoretical solution for now due to deficiency
of mature risk mitigation measures and
unreadiness of market.
LITERATURE CITED
Brockmann, R., G. Demmering, U. Kreutzer, M.
Lindemann, J. Plachenka and U. Steinberner,
Ullmann's Encyclopedia of Industrial Chemistry, Vol.
A10, 5th Ed., Wiley‐VCH, Weinheim, Germany.
2
Schultz, M. A., D. G. Stewart, J. M. Harris, S. P.
Rosenblum, M. S. Shakur and D. E. O' Brien,
" Reduce costs with dividing-wall columns, " CEP,
AIChE, May 2002.
3
Halvorsen, I. J., I. Dejanovic, S. Skogestad and Z.
Olujic, " Internal configurations for a multi-product
dividing wall column, " Chemical Engineering Research
and Design, Vol. 91, 2013.
4
Olujic, Z., I. Dejanovic, B. Kaibel and H. Jansen,
" Dimensioning multipartition dividing wall columns, " Chem. Eng.Technol., Vol. 8, Iss. 35, 2012.
5
I. Dejanovic, L. Matijasevic and Z. Olujic, " An effective method for establishing the stage and reflux
requirement of three-product dividing wall columns, " Chem. Biochem. Eng. Q., Vol. 25, Iss. 2, 2011.
1
NOTES
a
SimSci PRO/II
b
Sultech
QUAN YANG is a Sulzer Senior
Technical Expert, specializing
in mass transfer components.
He is in charge of air separation
knowledge management within
Sulzer Chemtech. Recently, his field
expanded to process optimization
for DWC. He holds a PhD in environmental engineering
from the National University of Singapore.
PATRICK FARQUET is the Head of
renewables and bio-based
applications at Sulzer Chemtech.
He leads research and development,
senior experts and innovation teams
with a focus on developing novel
processes in the fields of polymer
chemical recycling, biopolymers and production of
bio-based intermediates, oleochemicals and biofuels.
He holds a PhD in chemical engineering from the
Swiss Federal Institute of Technology (ETH) in Zürich.
PETER FAESSLER is a Senior
Technical Consultant in the field
of chemical engineering. He has
worked at Sulzer Chemtech for 38 yr,
holding various positions at different
locations including Switzerland,
Brazil, Mexico, Singapore and China.
WAN SEANG KEK is the Lead
Process Engineer under Sulzer
Chemtech's Global Biobased Group.
He has been working at Sulzer since
2002, holding various positions in
process engineering, technology
and sales. He specializes in
distillation technology and has vast experience in
oleochemicals and petrochemicals such as phenols,
ethanolamine and aromatics. He holds a BE degree
in chemical engineering.
KEEN HOE LUI is an Oleochemicals
Applications Manager at Sulzer
Chemtech, responsible for global
oleochemicals application
development. He has 18 yr of
process engineering and project
management experience in
oleochemicals and edible oils processing. Mr. Lui
holds a BE degree in chemical engineering from the
University of Birmingham, UK.
Hydrocarbon Processing | DECEMBER 2020
65
Hydrocarbon Processing - December 2020
Table of Contents for the Digital Edition of Hydrocarbon Processing - December 2020
Contents
Hydrocarbon Processing - December 2020 - Intro
Hydrocarbon Processing - December 2020 - Cover1
Hydrocarbon Processing - December 2020 - Cover2
Hydrocarbon Processing - December 2020 - Contents
Hydrocarbon Processing - December 2020 - 4
Hydrocarbon Processing - December 2020 - 5
Hydrocarbon Processing - December 2020 - 6
Hydrocarbon Processing - December 2020 - 7
Hydrocarbon Processing - December 2020 - 8
Hydrocarbon Processing - December 2020 - 9
Hydrocarbon Processing - December 2020 - 10
Hydrocarbon Processing - December 2020 - 11
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Hydrocarbon Processing - December 2020 - 14
Hydrocarbon Processing - December 2020 - 15
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Hydrocarbon Processing - December 2020 - 20
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Hydrocarbon Processing - December 2020 - 31
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Hydrocarbon Processing - December 2020 - 42
Hydrocarbon Processing - December 2020 - 43
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Hydrocarbon Processing - December 2020 - 47
Hydrocarbon Processing - December 2020 - 48
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Hydrocarbon Processing - December 2020 - 67
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Hydrocarbon Processing - December 2020 - 72
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Hydrocarbon Processing - December 2020 - 78
Hydrocarbon Processing - December 2020 - 79
Hydrocarbon Processing - December 2020 - 80
Hydrocarbon Processing - December 2020 - 80A
Hydrocarbon Processing - December 2020 - 80B
Hydrocarbon Processing - December 2020 - 81
Hydrocarbon Processing - December 2020 - 82
Hydrocarbon Processing - December 2020 - Cover3
Hydrocarbon Processing - December 2020 - Cover4
Hydrocarbon Processing - December 2020 - GP-1
Hydrocarbon Processing - December 2020 - GP-2
Hydrocarbon Processing - December 2020 - GP-3
Hydrocarbon Processing - December 2020 - GP-4
Hydrocarbon Processing - December 2020 - GP-5
Hydrocarbon Processing - December 2020 - GP-6
Hydrocarbon Processing - December 2020 - GP-7
Hydrocarbon Processing - December 2020 - GP-8
Hydrocarbon Processing - December 2020 - GP-9
Hydrocarbon Processing - December 2020 - GP-10
Hydrocarbon Processing - December 2020 - GP-11
Hydrocarbon Processing - December 2020 - GP-12
Hydrocarbon Processing - December 2020 - GP-13
Hydrocarbon Processing - December 2020 - GP-14
Hydrocarbon Processing - December 2020 - GP-15
Hydrocarbon Processing - December 2020 - GP-16
Hydrocarbon Processing - December 2020 - GP-17
Hydrocarbon Processing - December 2020 - GP-18
Hydrocarbon Processing - December 2020 - GP-19
Hydrocarbon Processing - December 2020 - GP-20
Hydrocarbon Processing - December 2020 - GP-21
Hydrocarbon Processing - December 2020 - GP-22
Hydrocarbon Processing - December 2020 - GP-23
Hydrocarbon Processing - December 2020 - GP-24
Hydrocarbon Processing - December 2020 - GP-25
Hydrocarbon Processing - December 2020 - GP-26
Hydrocarbon Processing - December 2020 - GP-27
Hydrocarbon Processing - December 2020 - GP-28
Hydrocarbon Processing - December 2020 - GP-29
Hydrocarbon Processing - December 2020 - GP-30
Hydrocarbon Processing - December 2020 - GP-31
Hydrocarbon Processing - December 2020 - GP-32
Hydrocarbon Processing - December 2020 - GP-33
Hydrocarbon Processing - December 2020 - GP-34
Hydrocarbon Processing - December 2020 - GP-35
Hydrocarbon Processing - December 2020 - GP-36
Hydrocarbon Processing - December 2020 - GP-37
Hydrocarbon Processing - December 2020 - GP-38
Hydrocarbon Processing - December 2020 - GP-39
Hydrocarbon Processing - December 2020 - GP-40
Hydrocarbon Processing - December 2020 - GP-41
Hydrocarbon Processing - December 2020 - GP-42
Hydrocarbon Processing - December 2020 - GP-43
Hydrocarbon Processing - December 2020 - GP-44
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_200904
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200903
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200902
https://www.nxtbook.com/nxtbooks/gulfpub/hp_200901
https://www.nxtbookmedia.com