non conventional oil 3-10-08
TRANSCRIPT
Non-Conventional Oil
Nonconventional Liquid Fuels
Syncrude
Extra-Heavy Oil, Oil Sands, Oil Shale
Synthetic Fuel
Coal, Natural Gas, Biomass Feedstocks
Renewable Fuels
Ethanol, Biodiesel
Convention Liquid Fuels
25 Billion Barrels per Year
Syncrude
Extra-Heavy Oil, Oil Sands, Oil Shale
3 Billion Barrels per Year
Synthetic Fuel
Coal, Natural Gas
~0.1 Billion Barrels per Year
Light versus Heavy Crude Oil
1.) Differences in density:
. Crude Specific Gravity
Light <0.870
Medium 0.870 to 0.920
Heavy >0.929
Extra-Heavy >1.000
(Alberta Heavy 0.945 to 1.007)
(Alberta Bitumen 1.014)
2.) Differences in Viscosity:
Crude Viscosity .
Light Crude ~ 50 cP Heavy Crude ~5,000 Extra Heavy Crude ~10,000 Bitumen ~100,000 Kerogen “Solid”
Non-Conventional Oil:
Syncrude
Extra-Heavy Crude,
Oil Sands,
Oil Shale
North America
South America
Middle East
Asia
Africa
Russia
Europe
Estimated Technically Recoverable Heavy Oil and Natural Bitumen
World Total: 1,085 bbl
North America
South America
Middle East
Extra-Heavy Crude
Extra-Heavy Crude
Largest Deposit, nearly 90% of World’s Extra-Heavy Oil:
Orinoco Heavy Oil Belt, Venezuela
- The Venezuelan national oil company says:
1,360 billion barrels (1.36 trillion) in place.
- About 20% could be recovered economically.
- Thus 270 billion barrels (0.270 trillion)
of oil reserves for the Orinoco belt.
(Comparable to the reserves of Saudi Arabia)
Extra-Heavy Crude Oil
Will flow in reservoir, but slowly.
In Venezuela:
In order to pump oil in pipelines,
emulsify with water.
Cannot be refined in traditional refineries.
Oil-Sands (Tar Sands)
Oil Sands (Tar Sands)
81% of world’s estimated oil-sand supply is in Canada
Oil sands: Bitumen in sand deposits at a 1% to 20% level
Bitumen won’t flow at room temperature, must be heated
Oil Sands: Extraction Methods
Open-Pit Mining
If bitumen is within 225 feet of surface, mine
sand, separate and process bitumen
In situ Process
If greater than 225 feet, two wells drilled,
steam injected into one, heated bitumen
comes out of the other
Currently, mostly open-pit mining is used, but 80% of the reserves are too deep for open-pit mining.
Upgrading In order to obtain syncrude for use in a refinery, must:
“Crack” large molecules to smaller, less viscous ones
Add hydrogen to carbon-rich, hydrogen-deficient molecules
Remove sulfur (5%) and nitrogen (0.6%)
Oil Shale
Oil Shale Enormous resources worldwide:
2.9 trillion barrels of “technically recoverable” oil
0.50 - 2.0 trillion barrels of “technically recoverable” oil in the USA
Extraction of shale oil:
Two methods, neither now in commercial operation:
1.) Underground mining and surface retorting of kerogen (1970s)
2.) in situ: Heat to 700 degrees F underground, vaporizing water to steam, shattering rock (under development by Shell Oil)
For one million barrels per day of shale oil:
By mining:
Requires 3 million barrels per day of water.
Mining and remediation of 500 million tons
of rock per year (about half the amount of
the annual tonnage of domestic coal
production).
In situ: Requires energy for heating
The “Old” Technologies• Cyclic steam stimulation• Steam drive (many variations)• Pressure-driven (p) processes
– High p water floods, solvents…
• Pressure-driven combustion processes– Wet or dry, forward or reverse, air or O2
• All these processes suffer from– Instability– Poor recovery, heat cost, well problems
New Production Technologies
• CHOPS (Cold Heavy Oil Prod. w. Sand)
• PPT (Pressure Pulsing Techniques)
• GAD (Gravity Assisted Drainage)– IGI (Inert Gas Injection)
– SAGD (Steam-Assisted Gravity Drainage)
– VAPEX (Vapor-Assisted Petr. EXtraction)
• Hybrids of these will be used
CHOPS
• The production of sand creates long channels or wormholes with high permeability.
• The combination of foamy oil behavior and the high permeability channels accounts for the high recovery factors and high production rates
CHOPS
For Successful CHOPS
• Foamy oil mechanism must be active (sufficient gas in solution)
• Continuous sand failure must occur (unconsolidated sands)
• No free water zones in the reservoir• PC pumps are necessary• Integrated sand handling system
– Sound sand disposal technology
• More profitable than thermal methods
• Very low CAPEX (cheap verticals)
• OPEX has been reduced
• NO Pumping issues (PC pumps can handle large sand %)
• Sand disposal has been solved
PPT• P - Pressure
• P - Pulsing
• T – Techniques
• Sharp pressure pulses applied to the liquid in wells
• Reduces advective instabilities
• Reduces capillary blockage effects
• Reduces pore throat blockage
• Increases the basic flow rate• Increases OOIP recovery• Reduces coning, viscous fingering• Reduces plugging by fines and
asphaltenes• Helps overcome capillary barriers at
throats• Emerging technology, much remains to
be optimized
GAD
• G – Gravity• A – Assisted• D – Drainage methods• Horizontal wells are essential• Flow is driven by density differences• Most effective with a gas phase• Wells produce slowly, but recovery ratios
can be very high, >90%
Inert Gas Injection
• Not for thermal heavy oil
• Good kv is required
• Ideal approach for converting old conventional fields to a GD process
• Operating expenses are quite low
• Should be considered for new fields, and for renewing old fields
THAI(Toe to Heel Air Injection)
• Toe-to-Heel Air Injection (THAI) is a new method that involves injecting air into the ground, which is then ignited.
• The fired-up air heats the oil, allowing it to be more easily lifted.
• The heat generated in the reservoir reduces the viscosity of the heavy oil, allowing it to drain into a second, horizontal well from where it rises to the surface.