US%20Coal%20resources

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US Coal resources
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World distribution of coal
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World coal production
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Problems with coal

• Like oil and natural gas it will not last forever
• Best estimates are 100-200 years
• Be skeptical of large estimates, based on new
  discoveries, new technologies
• It is not a clean fuel source, lots of
  environmental impact from using coal
• Environmental effects of surface (strip) mining
• CO2 (carbon dioxide) emissions impact environment
  (green house effect)
• SO2 (sulfur dioxide) emissions pose health risks
• Mining risks (mine accidents, black lung disease)
• Is it really cheap?
• From an NRC on the hidden costs of energy
  production
• In 2005 the total annual external damages from
  sulfur dioxide, nitrogen oxides, and particulate
  matter created by burning coal at 406 coal-fired
  power plants, which produce 95 percent of the
  nation's coal-generated electricity, were about
  62 billion
• This is twice as high as the cost of the coal
  itself

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Coal Liquefaction

• Process of producing synthetic fuel from coal
• Direct and indirect process to achieve this
• Direct
• Carbonization- produces coal tar, oil, water
  vapor, synthetic gas and char (a solid residue).
  Produces fluids that are of low quality for fuel.
• Hydrogenation add H2 to coal mixed with solvents
  and catalysts. No proven commercial value to the
  process
• Indirect Fischer-Tropsch process (coal
  gasification)
• Coal is gasified into syngas, which is converted
  to gasoline ad diesel.

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Coal gasification

• Process of producing coal gas, which can be
  converted into gasoline and diesel fuel and
  Hydrogen.
• Coal is heated and blown with oxygen and steam.
  Produces syngas, which can then be turned into
  gasoline as described on the previous slide.
• Or syngas is fed into another reaction which
  produces H
• Produces by-products which are environmentally
  damaging and need mitigation techniques
• Produces more CO2 than crude oil refinement-needs
  carbon sequestering technologies.

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Non-conventional fossil fuels

• Tar sands, shale gas and shale oil
• Until recently, these were not considered as a
  viable large scale contributors to our energy
  needs
• Technological advances and rising energy prices
  have brought shale oil and gas to the forefront
  as possible short term solutions

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Tar Sands

• Deposits of sand mixed with a thick hydrocarbon
  substance called bitumen
• Bitumen is so thick (viscous) that it does not
  flow. So sands must be transported to a
  processing plant.

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Locations

• Primarily in Canada
• Tar sands form where petroleum migrates upward
  into deposits of sand or consolidated sandstone.
  When the petroleum is exposed to water and
  bacteria present in the sandstone, the
  hydrocarbons often degrade over time into
  heavier, asphaltlike bitumen.
• 170 billion barrels considered economically
  recoverable.

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Tar sands processing

• Tar sand is placed in rotating
  drums along with water and
  caustic soda that separates the
  water, soda and bitumen.
• Bitumen is placed in a centrifuge and cracked
  into naptha, kerosene and heavy fuel oil
• Requires a lot of water (about 3 barrels of water
  for one barrel of oil produced
• Waste is stored on site in waste water ponds
• Similar energy density to shale oil, much less
  than coal

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In situ processing

• Two parallel horizontal oil wells are drilled in
  the formation. The upper well injects steam and
  the lower one collects the water that results
  from the condensation of the injected steam and
  the crude oil or bitumen.
• The injected steam heats the bitumen and lowers
  its viscosity, which allows it to flow down into
  the lower wellbore.
• The water and bitumen is recovered to the
  surface by several methods including a natural
  steam lift or by pumps that work well for moving
  high-viscosity fluids with suspended solids.

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Keystone XL Pipeline

• Proposed pipeline to deliver tar sands oil and
  bitumen (for further processing) to multiple
  locations in the US.
• Cost 7 billion

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Concerns about Keystone XL

• Portions cross known seismic regions
• Crosses native American reservations
• Concerns over damage to sacred sites
• Contamination from leaks or from tars sands
  production itself
• Leak or spill from any section would have
  environmental impacts
• Overall tar sands usage produces more greenhouse
  gasses than conventional oil
• Does not really address energy independence
• How much will be kept in the US vs being
  exported?
• If immediately approved, wont effect prices at
  the pump until 2014 and there is no consensus on
  its impact on gas prices, though it will be
  smaller than 10cents/gallon.
• Compare to TransAlaska pipeline
• 7 incidents in 35 years, 2 from sabotage(people
  putting holes in the pipeline), 1 from human
  error, 1 from earthquake(no leak), 3 from
  equipment failures

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Shale oil vs oil shale

• Shale Oil
• The oil produced from oil shale

• Oil Shale
• Also called kerogen shale
• Rocks that contain kerogen
• Kerogen a solid mixture of organic compounds from
  which shale oil can be produced
• Shale oil is a substitute for crude oil

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Oil Shale

• Oil Shale largest deposit is found in the Green
  River Formation
• 50 million years ago, this area was covered by 2
  large tropical lakes. Organic material at the
  bottom of the lakes combined with sediment and
  formed a carbon containing mudstone, called
  marlstone.

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Green River Formation
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Recovery methods

• Getting the oil is not easy, nor is it cheap, but
  it is becoming economically feasible. Same amount
  of coal produces much more energy.
• Traditional removal process require heating (a
  process called retorting) of the shale to remove
  the hydrocarbons which expands the remaining
  shale by 35. Need a deposit site to handle the
  waste
• This process also requires lots of water, Green
  River formation is in a very dry part of the
  country.
• In situ (on site) recovery methods are being
  developed to overcome these difficulties

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Recovery methods
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Recovery methods
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Recovery methods
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How much?

• 0.5-1.1 trillion barrels of technically
  recoverable oil shale oil in the US. (note that
  the word technically recoverable includes proved
  and unproved reserves)
• Based on current demand, this would provide the
  US with enough oil for 400 years.

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Shale Gas

• Gas deposits trapped in shale formations

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Fracking

• Hydraulic Fracturing
• A process which uses a high pressure liquid to
  create fractures or veins on rock to allow
  petroleum, natural gas or other substances to
  flow
• Used as far back as 1860s to extract oil in
  Pennsylvania, new York, West Virginia and
  Kentucky

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Issues

• Water useage Fracking takes a large volume of
  water. The average well uses 3-8 million
  gallons/week.
• Many of the chemical additives used are toxic and
  known carcinogens-possibility exists of
  contaminating ground water supplies
• Flowback the fracking fluids are further
  contaminated as they flow back through the wells
  by naturally occurring minerals and possibly
  naturally occurring radioactive substances
• Methane release-can cause explosions, can
  contaminate ground water and is a greenhouse gas
• Earthquakes-the additional fluid can cause fault
  lines to slip more easily

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Flaming Faucets?

• http//www.youtube.com/watch?vUrnnQ17SH_A

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How much?

• In the US, probably enough for about 100 years,
  at current rate of consumption
• If we increase consumption, this number will go
  down.
• Recovering methane from coal beds can offset the
  consumption increases a little