Hydrocarbon Processing - August 2021 - GP-15

SPECIAL FOCUS: SMALL-SCALE LNG
around $7/MMBtu to recover its capital
cost. This, in turn, requires an LNG selling
price of at least $18/MMBtu-considerably
higher than prevailing gas prices
but potentially competitive against diesel
or LPG. Furthermore, certain countries
offer incentives to encourage the development
of green renewable fuels, which
considerably enhance the economic viability
of such opportunities.
Flare gas recovery. Gas is flared from
many gas fields and processing plants.
The World Bank1
estimates from satellite
data that, in 2019, flared volumes exceeded
5 Tft3
and that almost half of the total
volume was generated in only four countries:
Russia, Iraq, the U.S. and Iran. With
the global move to net zero carbon, it
would be surprising if these volumes were
not targeted for recovery to beneficial use.
Flared gases are generally at atmospheric
pressure and may contain quantities
of heavier hydrocarbons. The gas
must be compressed, and the heavier hydrocarbons
recovered, before being fed to
the liquefaction section of an LNG plant.
The integrated heavies removal concept
of the liquefaction process provides for
the recovery of heavier hydrocarbons in
a cost-effective way that could result in
much-improved economics.
FIG. 8 illustrates the economics for a
20,000-tpy facility based on flare gas. This
excludes the revenue from heavies recovery,
which requires a case-by-case analysis
that considers the gas composition, as well
as the potential markets for the products.
Takeaway. Achieving economic viability
for small-scale LNG applications is challenging,
as they lack economy of scale relative
to conventional LNG schemes. Applications
are likely to be in the areas of liquid
fuel substitution, locations where conventional
fuel supplies are logistically difficult
or where environmental pressures prevail.
Rigorous optimization from both a
process design and detailed engineering
perspective, along with the adoption of
a lean, standardized, modular approach
allow significant expansion of opportunities
for small-scale LNG, to the benefit of
gas owners and their fuel customers. GP
NOTES
a
The dual methane expander process described in
Fig. 1 is the ZR-LNG system (Zero Refrigerant
LNG), which is owned, patented and licensed by
Gasconsult Ltd.
FIG. 7. Expected return on investment for a generic, 5,000-tpy biogas-based plant.
Generic, 20,000-tpy LNG plant IRR using flare gas
Gas price $0/MMBtu
60
40
Generic, 5,000-tpy LNG plant IRR using biogas
60
40
Gas price $0/MMBtu
Gas price $2/MMBtu
Gas price $5/MMBtu
Gas price $7/MMBtu
20
12
14
16
18
20
LNG selling price, $/MMBtu
22
24
20
12
14
16
18
LNG selling price, $/MMBtu
FIG. 8. Example economics for a 20,000-tpy facility based on flare gas.
b
c
The Integrated Heavies Removal process shown in Fig.
2 is owned, patented and licensed by Gasconsult Ltd.
The lean, standardized, modular, small-scale LNG
plants described in this article are engineered and
marketed by PolaireTech.
d
The proprietary, four-step work process used to optimize
the lean, standardized, modular design is the
Optimod Execution Work Process developed by
DyCat Solutions Inc.
LITERATURE CITED
1
World Bank, " Global gas flaring tracker report, "
Global Gas Flaring Reduction Partnership,
Washington, D.C., July 2020, online: https://pubdocs.worldbank.org/en/503141595343850009/
WB-GGFR-Report-July2020.pdf
FREEK
VAN HEERDEN is Managing
Director of PolaireTech. He
graduated from Pretoria University
in 1975 and joined AECI Limited in
Sasolburg, South Africa as a Process
Engineer. In 1998, he transferred to
Sasol, an international petrochemical
company, where he was involved in various coal and
GTL, polymer, clean fuels and renewable energy
projects globally as Engineering Manager and Technical
Director. He was also a founding member of Owner
Team Consultation, which assists owner organizations
in the development of new projects. In 2019,
PolaireTech was formed as a JV between Owner Team
Consultation and Saiyl, an EPC company, to develop
modular, small-scale LNG plant offerings.
FRED HANEY is President of DyCat
Solutions, a company that provides
innovative solutions to the heavy
industrial business sector. He is a
recognized leader in developing the
optimum capital efficiency for
owners of heavy industrial projects.
He has been globally recognized as a subject matter
expert for his development of modular designs,
practices and execution solutions. He is also the
inventor of Fluor's 3rd Gen Modular Execution.
GEOFF SKINNER is Technical
Director of Gasconsult. He
graduated from Oxford University
and joined Foster Wheeler in the UK
in 1965. From 1981 to 1986, he was
Technical Director of Foster
Wheeler Synfuels Corp. in
Livingston, New Jersey. On his return to the UK, Mr.
Skinner acted as a consultant to several multinational
companies and has registered a number of patents,
including LNG and hydrogen liquefaction processes.
Gas Processing & LNG | JULY/AUGUST 2021 15
20
22
24
IRR, %
IRR, %
https://pubdocs.worldbank.org/en/503141595343850009/WB-GGFR-Report-July2020.pdf https://pubdocs.worldbank.org/en/503141595343850009/WB-GGFR-Report-July2020.pdf https://pubdocs.worldbank.org/en/503141595343850009/WB-GGFR-Report-July2020.pdf
Hydrocarbon Processing - August 2021

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