Hydrocarbon Processing - January 2022 - 22
Sustainability
electric vehicles is expected to significantly
impact the long-term demand for
gasoline. However, despite the macro
changes in gasoline demand, the alkylate
outlook remains stable, offset by an increased
demand for higher-performance
fuels for high-efficiency engines.
Existing acid-based alkylation infrastructure
is aging and represents a
growing safety and financial risk for the
modern refiner. In the wake of a bankruptcy-causing
2019 HF alkylation unit
explosion at a U.S. refinery,3
In the U.S. and Europe, opporare
in the
Design Commercial
0.1
0.3
0.8
0.9
Isobutylene, wt%
Trans-2-butene, wt%
Cis-2-butene, wt%
Isopentane, wt%
1-pentane, wt%
1,3 butadiene, ppm
Methanol, ppm
38.5
14.8
11.8
11.6
9
13.9
-
-
50
TABLE 2. Mass balances
Stream
Mixed C4
Hydrogen
Feed
Saturated LPG
Supplementary isobutane
Total
Alkylate
Isobutane
N-butane
LPG
Products
Fuel gas
Acid soluble oil
Flare gas
Total
Alkylate yield
22 JANUARY 2022 | HydrocarbonProcessing.com
39.7
25.6
11.4
0.2
12.6
8.5
0.1
0.2
1,081.5
225
tunities for implementing this CIL-catalyzed
alkylation technologya
TABLE 1. Feed compositions
Constituent
Propane, wt%
Propylene, wt%
Isobutane, wt%
N-butane, wt%
1-butane, wt%
replacement, modernization and safety
enhancement of the legacy acid-based alkylation
processes.
In emerging or transitioning economies,
robust mobility growth in the populace
is expected to continue to drive modest
gasoline demand for the next decade.
In developing markets, the opportunity
for implementing the CIL-catalyzed alkylation
technologya
is in greenfield projects
or expansions of brownfield projects.
the rising
costs of insurance and safety are driving
refiners to consider inherently safer alternatives.4
Commercialization
and scale-up.
This CIL-catalyzed alkylation technologya
has
been under development
for two decades. Beginning with a 0.5bpd
continuous pilot testing project in
2003, the technology has been scaled up
to a commercial production capacity of
7,400 bpd.
In 2005, the first commercial field
demonstration was successfully
performed
at the PetroChina Lanzhou refinery
by retrofitting an existing H2
kylation unit with CIL catalysts.5
SO4 alIn
2013,
Deyang Chemical Co. Ltd., an independent
refiner, commissioned a greenfield
2,450-bpd unit.6
In 2018, PetroChina
Harbin Petrochemical Co. Ltd. implemented
the technology in a brownfield
operation at a scale of 3,700 bpd.7
Between 2017 and 2018, the Sinopec
group licensed the CIL-catalyzed alkylation
technology for three installations
(the Jiujiang, Wuhan and Anqing refineries),
each at a scale of 7,400 bpd.8
struction for the units was completed
ConDesign,
tph
37
0.08
5.23
3
45.31
35.85
0.7
6.18
1.63
0.9
0.05
45.31
79%
Commercial, tph
39.68
0.04
39.72
27.2
3.79
7
0.78
0.09
0.86
39.72
68%
between 2018-2020. Notably, the Sinopec
Wuhan unit was a revamp from an
existing HF-based alkylation process-
representing a major milestone and an
industry first.9
Commercial process performance.
The following section discusses the recently
commissioned brownfield 7,400bpd
CIL-catalyzed alkylation unit at Sinopec
Jiujiang Co.'s Jiangxi plant (FIG. 1),
which has a process operating flexibility
of 60%-110% and occupies a plot space
of 126 m x 74 m. The unit is designed to
handle mixed olefin feedstocks from both
methyl tertiary-butyl ether (MTBE) and
fluid catalytic cracking (FCC) units.
The turnkey capital cost for the unit
(including engineering, procurement,
construction, commissioning and inspections)
was approximately $78 MM
and included the installation of four key
sections: a feed pretreatment system, a
reaction system, a catalyst regeneration
system and a product separation/purification
system. Sinopec Engineering
Construction Co. Ltd. led the engineering
aspects of the project, while Sinopec
Nanjing Engineering Co. undertook the
construction works.
After 1 yr of construction, mechanical
completion was achieved in 4Q 2018, and
the unit was commissioned 1Q 2019. In
2Q 2019, the operator conducted a calibration
test to benchmark and compare
commercial process performance data
against design specifications and to identify
optimization opportunities. At the
time of this publication, no safety-related
incidents or concerns have been identified
by the operator.
TABLE 1 compares the commercial and
design feed compositions. Although the
isobutane content of the commercial feed
(39.7 wt%) was comparable to that of the
design basis (38.5 wt%), the total C4
olefin
content of the commercial feed (32.7
wt%) was significantly lower than expected
(46.3 wt%). Further, the non-reactive
n-butane content in the commercial feed
(25.6 wt%) was significantly higher than
the design basis (14.8 wt%), and the commercial
feed also contained contaminates,
namely 1,3 butadiene and methanol.
The CIL-catalyzed alkylation techis
intended to stoichiometrically
nologya
react isobutane with C4
sign basis anticipated that C4
olefins. The deolefins
feedstock
would be supplied in excess relative
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Hydrocarbon Processing - January 2022
Table of Contents for the Digital Edition of Hydrocarbon Processing - January 2022
Contents
Hydrocarbon Processing - January 2022 - Cover1
Hydrocarbon Processing - January 2022 - Cover2
Hydrocarbon Processing - January 2022 - Contents
Hydrocarbon Processing - January 2022 - 4
Hydrocarbon Processing - January 2022 - 5
Hydrocarbon Processing - January 2022 - 6
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Hydrocarbon Processing - January 2022 - 81A
Hydrocarbon Processing - January 2022 - 81B
Hydrocarbon Processing - January 2022 - 82
Hydrocarbon Processing - January 2022 - Cover3
Hydrocarbon Processing - January 2022 - Cover4
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