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Introduction to Introduction to “Conventional” Natural “Conventional” Natural GasGasKenneth M. Klemow, Ph.D.BIO / EES 105 at Wilkes University
What is natural gas?What is natural gas?Composed mainly of methane
and other molecules.
About methane:•Energy content: 55.7 kJ/g•Vaporization point: -260oF 160oC
NG has two general formsNG has two general forms◦Thermogenic – From breakdown of
fossil organic matter below earth’s surface Hundreds of feet to miles below surface Need heat and pressure
◦Biogenic – From breakdown of organic matter at earth’s surface. Decomposition without oxygen Wetlands, garbage dumps
Wet Gas Vs Dry GasWet Gas Vs Dry GasDry gas – mainly methaneWet gas – includes ethane,
propane butane
Conventional vs Conventional vs Unconventional Natural GasUnconventional Natural Gas• Conventional gas
–Relatively easy to extract–Forms include
• Associated with oil• Not associated with oil• Can be onshore or offshore
• Unconventional gas–More difficult to extract–Derived from
• Shale, coal-bed
Geology of gasGeology of gas
http://www.safehaven.com/article/16566/shale-gas-miracle-pill-or-empty-promise
Focus on Conventional Focus on Conventional GasGas
How does thermogenic NG How does thermogenic NG form?form?Organic matter gets buried by
other sedimentsBreaks down without oxygen under
pressure, forming hydrocarbonsTemperature dependent
◦Lower – petroleum◦Higher – methane
Often gas mixed with petroleum, released when pressure reduced.
History of natural gas History of natural gas developmentdevelopmentFirst isolated by Chinese about
500 BC.◦Captured gas seeping from ground,
piped it using crude pipelines.Mid-19th Century
◦Burned off during oil production (flaring)
Early 20th Century◦Pipelines constructed to capture and
transport
Historic Gas ProductionHistoric Gas Production
Conventional gas production Conventional gas production - US- US
Gas utilizationGas utilizationEnergy
◦Electrical generation◦Heating / cooking◦Transportation
Feedstock for industrial processes◦Plastics◦Organic chemicals◦Fertilizers
Energy use of natural gasEnergy use of natural gas
http://www.c2es.org/publications/natural-gas-markets-use-overview
Conventional well Conventional well productionproductionGeologists find
gas reservoirDrill boreholeCase well in
steel and concrete
Gas flows upward
Captured into pipeline
Wells sometimes need to be Wells sometimes need to be stimulatedstimulatedAdd acid,
water, or gases to promote NG flow from the well
http://www.businessweek.com
Natural gas must be Natural gas must be processedprocessedRemove impurities
◦Hydrocarbons (ethane, propane, butane)
◦Hydrogen sulfide◦Water vapor◦Nitrogen compounds
Gas distribution systemGas distribution system
http://www.c2es.org/publications/natural-gas-infrastructure
Major NG pipelines in USMajor NG pipelines in US
NG can be compressed and NG can be compressed and liquifiedliquifiedBoth reduce volume making it
easier to transport
CNG – Compressed to 1% CNG – Compressed to 1% original volumeoriginal volumeUsed as a fuel for vehicles
◦Cars, trucks, buses, locomotives◦Some engines run on both CNG and
gasoline◦Common in Iran, Pakistan, Argentina,
Brazil◦Efforts to increase use in US
http://gas2.org/http://www.ngvglobal.com/
LNG – Cooled to -260LNG – Cooled to -260ooFFHas 2.4 times more energy than
CNGTransported via trucks and ships
where pipelines not presentMust be stored in cryogenic tanksNot used as fuel
http://ubpost.mongolnews.mn http://cryptome.org/eyeball/lng/lng-eyeball.htm
Conventional gas production Conventional gas production – worldwide– worldwide
Location of conventional Location of conventional natural gasnatural gas
Pricing natural gasPricing natural gasNatural gas sold by volume
◦Typical basis 1000 cubic feet (Mcf)◦Also used
1 million cf (MMcf) 1 billion cf (Bcf) 1 trillion cf (Tcf)
◦1 Mcf = 1 million BTU
Pricing natural gasPricing natural gasDifferent prices often quoted
◦Wellhead – Unprocessed NG at well◦Henry Hub – Port in Louisiana, used as
basis for NY Mercantile Exchange Futures price – Contract price for specified
amount of gas at specified time
◦City Gate – Price paid by utility receiving gas from major pipeline
◦Electric Power price – Paid by electric utility
◦Residential price – Paid by consumer
Pricing natural gasPricing natural gas
http://geology.com/articles/natural-gas-prices/
Pricing long term trendPricing long term trend
http://geology.com/articles/natural-gas-prices/
Pricing NG – more recentlyPricing NG – more recently
http://marketrealist.com/2013/05/natural-gas-rig-count-fell-by-four-last-week-down-20-since-start-of-2013/
Pricing NG – Comparing Pricing NG – Comparing fuelsfuels
http://www.aei-ideas.org/2013/02/us-households-will-save-billions-in-2012-from-falling-natural-gas-prices-offsetting-higher-gasoline-prices/
Pricing NG – Effects of Pricing NG – Effects of seasonseason
International price trendsInternational price trends
http://ourfiniteworld.com/2012/03/23/why-us-natural-gas-prices-are-so-low-are-changes-needed/
Benefits of Conventional Benefits of Conventional Natural GasNatural Gas
High energy densityLess polluting than coalEasy to transportDoes not cause radioactivityReliable
Drawbacks of Conventional Drawbacks of Conventional Natural GasNatural GasBurning releases greenhouse
gasesDrilling and pipelines impacts
habitatSupplies dwindling