Hydrocarbon Processing - August 2021 - GP-30

ENGINEERING AND DESIGN
Sour water from existing slug
catchers and three-phase separators
Existing facility
New facility
Acid gas
Existing facility upgrade
C-201, existing stripper
capacity = 5,000 bpd
D-X06, existing
pre-flash drum
D-X12, existing sour
water filter
Treated water
G-X03, existing
feed pump
Feed sour water from
gas compression project
FCV
New SWS capacity =
5,000 bpd
One 100% new
pre-flash drum,
design flow = 8,900 bpd
Three 50% new, degassed
sour water pumps,
design flow = 8,900 bpd
FIG. 9. Simple sketch for integration of existing SWS with new SWS train.
isting SWS train, it was recommended that a new, smaller SWS
train should be provided with all tie-in points to the existing
SWS. This would allow operational flexibility during normal
operations, as well as during maintenance, turnaround and inspection.
FIG. 9 provides the equipment design capacity for a
new SWS train and its integration with the existing SWS. The
scope of work for integration under the new project is shown
in dark blue color.
Lessons learned. Based on the assessment findings from the
process simulations and the actual field performance tests, it
was concluded that the existing SWS unit is capable of processing
5,000 bpd of sour water as per nameplate capacity, while
maintaining specification for H2
S in the effluent water.
Although the existing SWS unit is capable of processing the
sour gas feed at its original design capacity, the following design
deficiencies and key operational issues for this unit needed
to be addressed to sustain the performance:
* High solids loading in the sour water feed contaminated
the system, which impacted the overall performance
of the unit
* Manual operation mode was identified as one of the
main challenges to maintaining stable operation of the
SWS, especially at maximum design rates.
This study also produced several takeaway messages related
to sour water stripping:
* Proper cleaning is required to remove the solids in
process equipment that impact SWS operations
* The SWS should be operated in auto mode, with both
the sour feedwater and treated water pumps in operation
30 JULY/AUGUST 2021 | GasProcessingNews.com
* The SWS column operating temperature should be
controlled as per the design data, by maintaining
the ratio of steam flowrate to sour water flowrate
close to the design value. GP
LITERATURE CITED
1
2
3
4
5
Lieberman, N. P., Process Engineering for a Small Planet, Wiley, Hoboken, New
Jersey, 2010.
Saudi Aramco engineering standard for sour water stripper design, SAES-A-16,
GPSA, Sour water stripper design.
Weiland R. H. and N. A. Hatcher, " Sour water strippers exposed, " Laurence Reid
Gas Conditioning Conference, Norman, Oklahoma, February 28, 2012.
Addington, L., C. Fitz, K. Lunsford, L. Lyddon and M. Siwek, " Sour water:
Where it comes from and how to handle it, " Digital Refining, September 2011.
Ponting, J., H. Z. Kister and R. B. Nielsen, " Troubleshooting and solving a
sour water stripper problem: A systematic approach identifies problems that
prevented a stripper column from achieving trouble-free operation, " Chemical
Engineering, Vol. 120, Iss. 11, November 2013.
MUHAMMAD RIZWAN TARIQ is a Senior Process Engineer
at the process and control systems department of
Saudi Aramco in Dhahran, Saudi Arabia. He has also served
as Staff/Senior Engineer at JGC Japan, Worley Oman,
PDO Oman and OGDCL Pakistan. He holds a BS degree in
chemical engineering from Punjab University in Lahore,
Pakistan. He is also a Chartered Member of IChemE UK
and a Professional Engineer with PEC Pakistan.
TAIB ABANG is an Engineering Specialist at the process and
control systems department of Saudi Aramco in Dhahran,
Saudi Arabia. He has also served as a Senior Engineer at
Petronas LNG in Malaysia. He holds a BS degree in chemical
engineering from University Malaya in Kuala Lumpur, Malaysia.
He is a Chartered Engineer from the Engineering Council
and a Chartered Member of IChemE UK.
FCV
One 100% new sour
water feed tank, design
flow = 8,900 bpd
Three 50% new sour water
feed filters and coalescers,
design flow = 5,000 bpd
Three 50% new sour
water feed pumps,
design flow = 8,900 bpd
Treated water
Acid gas
http://www.GasProcessingNews.com
Hydrocarbon Processing - August 2021

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