Introduction to Gas Transportation and Storage technology including pipeline, CNG, LNG, GTL, GTW, methane hydrate, and the importance of gas sales agreement in a gas value chain.

1. Introduction to
Gas Transportation
By Puput Aryanto Risanto
22 December 2016

2. Oil & Gas Industry
Upstream Midstream Downstream
Finding, lifting, and
processing oil & gas
from subsurface into
surface and ready for
transportation. Also
known as Exploration
and Production (E&P).
Transportation and
storage of crude oil
and natural gas from
E&P plant for further
processing by
pipeline, railway, road,
or tanker.
Processing of crude oil
and natural gas into
useful final product or
raw material for other
industry. Also known as
Refining & Marketing
(R&M)

3. Gas Dilemma
• In the early history of oil industry, natural gas in
considered by-product (waste) during drilling
attempt for searching oil. Only gas found during
drilling is considered failure since gas is flammable
and cannot be processed & stored.and cannot be processed & stored.
• Gas can only be contained in a pipe and burnt
immediately in a safe place, either for heating,
boiling water, or burnt for nothing, known as flare.
Oil in Alberta on 1950 Canadian postage stamp,
showing two drilling derricks, storage tanks, and
flaring of "waste" gas,1914 - 1918 era.

4. Gas Problem
• Not like crude oil which is liquid in room temperature (25oC
/ 77oF) & atmospheric pressure (1 atm / 101,325 Pascal /
14.7 psi), natural gas is gaseous state in room temperature
& atmospheric pressure.
• Gas has lower density than oil, meaning in a same volume,
gas has lower mass & energy density.gas has lower mass & energy density.
• In room temperature & atmospheric pressure, gas will
occupy very large space, hence it’s not practical &
economic to store gas in this state.
• Since can’t be stored naturally, gas must be used or
transported immediately if required in other place.
• Gas delivery must match requirement, excess gas can only
be flared (burnt) or vented (released to atmosphere).

5. Ideal Gas Equation
• Behaviour of gas in many condition can be
described in Ideal Gas Equation
pV = nRT or V = (nRT) / p
• Where p = pressure, V = volume, n = gas• Where p = pressure, V = volume, n = gas
amount (number of mole), R = ideal gas
constant, and T = temperature.
• It means to reduce Volume, we must
reduce Temperature or increase Pressure
(or both) since n is given and R is constant.

6. Gas Value
• Despite all known problems, gas has several advantages
over oil or coal, i.e. :
– Cleaner fuel (less emission) for power plant & vehicle
– Cheaper than oil-based fuel, i.e. gasoline
– Can be used as a feed stock / raw material of– Can be used as a feed stock / raw material of
petrochemical industry like fertilizer
• With all above advantages, gas demand slowly grows and
oil company start thinking to monetize its gas reserve.
• Gas must be transported from the wellhead to the
customer to bring value to the producer.
• Gas company shall regulate the volume to match
customer requirement while minimizing wasted gas.

7. Gas Monetization
• To bring the optimum value of gas, method of gas
transportation & storage becomes very critical.
• Remember, as per ideal gas equation, gas must be
compressed and/or cooled to reduce the volume.
• Gas can also be converted into another form and
transported in the new form.transported in the new form.
• The technology used to reduce the gas volume or convert
into another form will depend mainly on the gas delivery
volume and distance from gas producer to gas consumer.
• However, it will also depend on the price, consumer
requirement, and technology maturation.

8. Gas Transportation Technology
Technology Vol Reduction
Pipelines 70-100
CNG 250-300
LNG 600
Hydrated 150-200Hydrated 150-200
CNG : Compressed Natural Gas
LNG : Liquefied Natural Gas
GTL : Gas To Liquid
GTW : Gas To Wire

9. Technology Selection
GTL LNG and/or GTL
• Pipeline is the
traditional, well proven
method and the most
economic for short
distance
• LNG is used for large
volume gas in a veryvolume gas in a very
long distance
• CNG is used when the
volume is not economic
enough for LNG
• GTL is the most
advance method to
convert low value gas
into high value liquid,
hence small volume can
be made economic

10. Pipeline
• Pipeline is a long pipe for conveying fluid (oil, gas,
water, etc) over long distance.
• Gas must be compressed by a gas compressor in
order to be able to receiving point.
• Pipeline is only for gas transporting, even tough• Pipeline is only for gas transporting, even tough
sometimes it is used as “gas temporary storage.”
• Gas compression ratio in a pipeline depends on
the gas volume delivery, distance, inlet pressure
and required pressure on the receiving point.

11. Gas Booster Station
• If the distance is very long, a gas compressor
might be placed between pipeline section known
as booster compressor
Multi-stage booster pump, use the same principle like booster compressor

12. Compressed Natural Gas (CNG)
• Gas is compressed up to 20-25 Mega (million)
Pascal / 2900-3600 psi and stored in a hard tank,
normally in cylindrical or spherical shape, known
as CNG (Compressed Natural Gas). CNG only
occupy less than 1% of space compare to volumeoccupy less than 1% of space compare to volume
in atmospheric pressure.
• CNG can be transported via road & sea, and can
be easily used by reducing its pressure.
• However, for large quantity over long distance,
CNG is considered not economical.

13. CNG transportation
CNG transportation
concept vessel
(enersea.com)
CNG distributionCNG distribution
truck

14. Liquefied Natural Gas (LNG)
• In this method, gas is cooled down to -161
o
C / -
256
o
F at atmospheric pressure till condenses to a
clear, colorless, and odorless, liquid know as LNG.
• This liquefaction reduce the volume by 600 times,
makes it very economic for large volumemakes it very economic for large volume
transportation over very long distance.
• Natural gas must be purified to contain only
methane and ethane (or 100% methane) before
supercooled to form LNG.
• LNG will be converted back to a gas form in the
receiving facility, known as regasification terminal.

15. LNG process diagram
LNG process diagram at PT Badak NGL, Bontang, Indonesia

16. LNG value chain

17. Gas To Liquid (GTL)
• Many confusion the difference between GTL and
LNG since both contain “Liquid & Gas” term.
• While LNG is a physical reaction to convert natural
gas (methane) in a gas form to a liquid form, GTL
is a chemical reaction to convert natural gasis a chemical reaction to convert natural gas
(methane) in a gas form to a different, more
complex, and valuable substance in a liquid form.
• GTL process is much more complex and costly,
hence not much GTL plant in the world compare to
LNG plant.

18. GTL definition & history
• A chemical process to convert natural gas into
synthetic liquid (can be crude oil, diesel fuel,
aviation fuel, or gasoline) through Fischer-Tropsch
(FT) process.
• Originally invented in early 1920 by German• Originally invented in early 1920 by German
chemist Franz Fischer and Hans Tropsch in
Germany which later on used by the Germany
during World War II.
• Highly exothermic (produce a lot of heat) which
can be used to generate steam or power.

19. GTL process
• Major steps in GTL process :
Remove impurities such as mercury & hydrogen sulphide
Produce synthesis gas from Natural Gas and Air / Oxygen.
FT synthesis to convert synthesis gas to long chain, heavy
paraffinic liquid. Paraffin is a mixture of high-molecular-
weight alkanes (i.e., saturated hydrocarbons with the
general formula CnH2n+2, where n is an integer).
• Byproducts is large amount of water and small amount of
CO2, olefins, oxygenates, and alcohol.

20. Simplified GTL block diagram
GTL can
convert
natural gas
into more
valuable liquid
like kerosene,
gasoline, and
LPG.
Conversion
ratio is about
10 thousand
of cubic feet
(mcf) raw gas
into 1 barrel
liquid product.

21. Gas To Wire (GTW)
• GTW is a term of converting gas into electricity in a location
close to (or even on top of) a gas field and transfer the
electric power to the customer via transmission and
distribution lines.
• Gas is used as a fuel of gas turbine (or gas engine in a
small scale) driving a power generator.small scale) driving a power generator.
• In a large scale, waste heat from a gas turbine can be used
to convert water into steam to turn steam turbine connected
to other or same power generator. This configuration is
known as Combined Cycle Gas Turbine Power Plant.
• Technical-commercial evaluation must be carefully
conducted whether building power plant close to gas field
(GTW) or transfer gas to power plant close to consumer.

22. Combined Cycle Gas Turbine
1. Air is compressed
in a compressor,
then mixed with the
gas fuel
2. Combustor ignites
air-gas mix, then
turn the gas turbine
3. Hot excess gas3. Hot excess gas
convert water into
steam in a Heat
Recovery Steam
Generator (HRSG)
4. Steam turns steam
turbine
5. Both gas & steam
turbine drive single
generator to
produce electricity
Simplified CCGT Power Plant block diagram

23. Methane Hydrate
• Methane hydrate / gas hydrate / methane ice / fire ice /
methane clathrate is a solid clathrate (chemical substance
consisting of a lattice that trap molecules) in which large
amount of methane (the biggest portion of natural gas) is
trapped within crystal structure of water, forming a solid
similar to ice.similar to ice.
• It is found naturally under sediments on the ocean floor.
• Method to transfer natural gas in the form of methane
hydrate is still under experiment, yet to commercialized.

24. Gas Sales Agreement (GSA)
• Due to high investment of gas production facility, long term
gas sales agreement must be established first prior to gas
field development.
• Normally, agreement must exist for at least 10 years.
• The most critical factor is gas price calculation.
• Gas price depends on field complexity, gas delivery• Gas price depends on field complexity, gas delivery
volume, sales period, seller economic criteria, buyer
capability, and local law & regulation.
• Gas price may be fixed over sales period, but normally it is
a function of oil price with floor (min) price to protect seller
and ceiling (max) price to protect buyer.
• That’s why, not like oil price which is same for similar oil
quality, gas price can vary even for the similar gas quality.

25. Thank YouThank YouThank YouThank You –––– TerimaTerimaTerimaTerima KasihKasihKasihKasih
Petronas FLNG Satu (PFLNG Satu)
The world first Floating LNG on stream

26. About the Author
Puput Aryanto Risanto, PMP is a Project
Management Professional certified Sr. Project
Engineer with 12+ years experience in oil &
gas industry. Currently he is working for
Premier Oil Natuna Sea B.V. in Jakarta,
Indonesia. Previously he worked for Petronas
Carigali Sdn. Bhd. in KL, Malaysia, Premier OilCarigali Sdn. Bhd. in KL, Malaysia, Premier Oil
Natuna Sea B.V. in Jakarta and Total E&P
Indonesie in Balikpapan, Indonesia.
His expertise includes project engineering & management,
joint venture management, engineering & construction
management, & electrical engineering-construction-
inspection. He can be contacted at email
aryantorisanto@yahoo.com or linkedin Puput Aryanto Risanto.