Hydrocarbon Processing - August 2021 - 17

Valves, Pumps and Turbomachinery
grids. FIG. 5 shows the variation of key parameters
in the spent catalyst route from
January to September 2020. The apparent
catalyst density in the stripper was 780
kg/m3
decrease in late April, and then decreased
to 100 kg/m3
from January to April. It began to
from July to September, as
shown in FIG. 5A.
Meanwhile, the opening of the spent
slide valve increased from 37% to 63%, and
the pressure drop decreased from 77 kPa
to 5 kPa, as shown in FIG. 5B, which indicated
that the catalyst flowrate sharply decreased.
The decrease in flowrate may have
been caused by the coking in the grates,
which decreased the catalyst flow area.
During plant maintenance in September
2020, the soft coke that had accumulated
in the bottom of the stripper grids was removed,
revealing that only 20% of the catalyst
flow area remained, as shown in FIG. 6.
Proposed treatment. During the stem
fracture of the regeneration slide valve, the
crude oil processing was negatively impacted.
The FCCU needed to operate until
September 2020 for shutdown maintenance.
To realize stable control of catalyst
circulation rate and reaction temperature,
engineers carried out much experimental
research. Finally, a double-valve control
online treatment technology was adopted
to solve the problem. In addition, the
smooth control of catalyst circulation rate
was realized by adjusting the flow pattern
of catalyst in the vicinity of the regeneration
slide valve.
Double-valve control technology.
The double-valve control technology refers
to the installation of stems on either
A
1,000
800
600
400
200
1
2
Apparent density in stripper
80
60
40
20
3
4
5
6
Time, mos
7
8
9
10
1
2
3
4
5
6
Time, mos
FIG. 5. Parameter profiles of spent catalyst route: (a) apparent density in stripper and (b)
opening value and pressure drop of the spent slide valve.
7
8
9
10
side of the slide valve disc for bidirectional
driving of the disc, as shown in FIG. 7A. For
this device, due to the fracture of the old
stem, the valve plate could be pushed only
to close rather than to pull open, as shown
in FIG. 7B. The technician choose to make
a new hole on the regeneration slide valve
and set a new stem in the direction opposite
the old stem, as shown in FIG. 7C. The
new stem was then used with the old stem
to control the opening of the slide valve.
Reactor temperature control. The
double-valve control technology guaranB
80
60
40
20
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WEBCAST
Thursday, August 19, 2021 | 10 a.m. CDT / 3 p.m. GMT
Nicholas Corbett
Head of Research, Aeroderivative
Gas Turbine Services
Siemens Energy
Decarbonizing Downstream: Compression and
Driver Equipment Technologies and Applications
Refi neries and other industrial plants are under increased pressure to reduce their
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Michael Mallozzi
Project Development Manager,
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Please join us for this webcast and learn how technical advances in gas turbines and
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* Advances in portfolio and technologies addressing climate impact
* Gas turbine preparedness for hydrogen/hybrid fuel transition
* Centrifugal and reciprocating compressor technologies and applications
Register for Free:
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Mike Rhodes
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Hydrocarbon Processing
Hydrocarbon Processing | AUGUST 2021 17
ρ, kg/m3
Opening value, %
∆P, kPa
http://www.HydrocarbonProcessing.com/Webcasts

Hydrocarbon Processing - August 2021

Table of Contents for the Digital Edition of Hydrocarbon Processing - August 2021

Contents
Hydrocarbon Processing - August 2021 - Intro
Hydrocarbon Processing - August 2021 - Cover1
Hydrocarbon Processing - August 2021 - Cover2
Hydrocarbon Processing - August 2021 - Contents
Hydrocarbon Processing - August 2021 - 4
Hydrocarbon Processing - August 2021 - 5
Hydrocarbon Processing - August 2021 - 6
Hydrocarbon Processing - August 2021 - 7
Hydrocarbon Processing - August 2021 - 8
Hydrocarbon Processing - August 2021 - 9
Hydrocarbon Processing - August 2021 - 10
Hydrocarbon Processing - August 2021 - 11
Hydrocarbon Processing - August 2021 - 12
Hydrocarbon Processing - August 2021 - 13
Hydrocarbon Processing - August 2021 - 14
Hydrocarbon Processing - August 2021 - 15
Hydrocarbon Processing - August 2021 - 16
Hydrocarbon Processing - August 2021 - 17
Hydrocarbon Processing - August 2021 - 18
Hydrocarbon Processing - August 2021 - 19
Hydrocarbon Processing - August 2021 - 20
Hydrocarbon Processing - August 2021 - 21
Hydrocarbon Processing - August 2021 - 22
Hydrocarbon Processing - August 2021 - 23
Hydrocarbon Processing - August 2021 - 24
Hydrocarbon Processing - August 2021 - 25
Hydrocarbon Processing - August 2021 - 26
Hydrocarbon Processing - August 2021 - 27
Hydrocarbon Processing - August 2021 - 28
Hydrocarbon Processing - August 2021 - 29
Hydrocarbon Processing - August 2021 - 30
Hydrocarbon Processing - August 2021 - 31
Hydrocarbon Processing - August 2021 - 32
Hydrocarbon Processing - August 2021 - 33
Hydrocarbon Processing - August 2021 - 34
Hydrocarbon Processing - August 2021 - 35
Hydrocarbon Processing - August 2021 - 36
Hydrocarbon Processing - August 2021 - 37
Hydrocarbon Processing - August 2021 - 38
Hydrocarbon Processing - August 2021 - 39
Hydrocarbon Processing - August 2021 - 40
Hydrocarbon Processing - August 2021 - 41
Hydrocarbon Processing - August 2021 - 42
Hydrocarbon Processing - August 2021 - 43
Hydrocarbon Processing - August 2021 - 44
Hydrocarbon Processing - August 2021 - 45
Hydrocarbon Processing - August 2021 - 46
Hydrocarbon Processing - August 2021 - 47
Hydrocarbon Processing - August 2021 - 48
Hydrocarbon Processing - August 2021 - 49
Hydrocarbon Processing - August 2021 - 50
Hydrocarbon Processing - August 2021 - 51
Hydrocarbon Processing - August 2021 - 52
Hydrocarbon Processing - August 2021 - 53
Hydrocarbon Processing - August 2021 - 54
Hydrocarbon Processing - August 2021 - 55
Hydrocarbon Processing - August 2021 - 56
Hydrocarbon Processing - August 2021 - 57
Hydrocarbon Processing - August 2021 - 58
Hydrocarbon Processing - August 2021 - 59
Hydrocarbon Processing - August 2021 - 60
Hydrocarbon Processing - August 2021 - 61
Hydrocarbon Processing - August 2021 - 62
Hydrocarbon Processing - August 2021 - 63
Hydrocarbon Processing - August 2021 - 64
Hydrocarbon Processing - August 2021 - 65
Hydrocarbon Processing - August 2021 - 66
Hydrocarbon Processing - August 2021 - 67
Hydrocarbon Processing - August 2021 - 68
Hydrocarbon Processing - August 2021 - 69
Hydrocarbon Processing - August 2021 - 70
Hydrocarbon Processing - August 2021 - 71
Hydrocarbon Processing - August 2021 - 72
Hydrocarbon Processing - August 2021 - 73
Hydrocarbon Processing - August 2021 - 74
Hydrocarbon Processing - August 2021 - 75
Hydrocarbon Processing - August 2021 - 76
Hydrocarbon Processing - August 2021 - 77
Hydrocarbon Processing - August 2021 - 78
Hydrocarbon Processing - August 2021 - 79
Hydrocarbon Processing - August 2021 - 80
Hydrocarbon Processing - August 2021 - 81
Hydrocarbon Processing - August 2021 - 82
Hydrocarbon Processing - August 2021 - Cover3
Hydrocarbon Processing - August 2021 - Cover4
Hydrocarbon Processing - August 2021 - GP-1
Hydrocarbon Processing - August 2021 - GP-2
Hydrocarbon Processing - August 2021 - GP-3
Hydrocarbon Processing - August 2021 - GP-4
Hydrocarbon Processing - August 2021 - GP-5
Hydrocarbon Processing - August 2021 - GP-6
Hydrocarbon Processing - August 2021 - GP-7
Hydrocarbon Processing - August 2021 - GP-8
Hydrocarbon Processing - August 2021 - GP-9
Hydrocarbon Processing - August 2021 - GP-10
Hydrocarbon Processing - August 2021 - GP-11
Hydrocarbon Processing - August 2021 - GP-12
Hydrocarbon Processing - August 2021 - GP-13
Hydrocarbon Processing - August 2021 - GP-14
Hydrocarbon Processing - August 2021 - GP-15
Hydrocarbon Processing - August 2021 - GP-16
Hydrocarbon Processing - August 2021 - GP-17
Hydrocarbon Processing - August 2021 - GP-18
Hydrocarbon Processing - August 2021 - GP-19
Hydrocarbon Processing - August 2021 - GP-20
Hydrocarbon Processing - August 2021 - GP-21
Hydrocarbon Processing - August 2021 - GP-22
Hydrocarbon Processing - August 2021 - GP-23
Hydrocarbon Processing - August 2021 - GP-24
Hydrocarbon Processing - August 2021 - GP-25
Hydrocarbon Processing - August 2021 - GP-26
Hydrocarbon Processing - August 2021 - GP-27
Hydrocarbon Processing - August 2021 - GP-28
Hydrocarbon Processing - August 2021 - GP-29
Hydrocarbon Processing - August 2021 - GP-30
Hydrocarbon Processing - August 2021 - GP-31
Hydrocarbon Processing - August 2021 - GP-32
Hydrocarbon Processing - August 2021 - GP-33
Hydrocarbon Processing - August 2021 - GP-34
Hydrocarbon Processing - August 2021 - GP-35
Hydrocarbon Processing - August 2021 - GP-36
Hydrocarbon Processing - August 2021 - GP-37
Hydrocarbon Processing - August 2021 - GP-38
Hydrocarbon Processing - August 2021 - GP-39
Hydrocarbon Processing - August 2021 - GP-40
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