The document discusses enhanced oil recovery (EOR) methods, focusing on steam injection. It defines EOR as techniques for extracting more crude oil from reservoirs beyond primary and secondary recovery methods. Steam injection is a thermal EOR method that involves injecting steam into reservoirs to lower oil viscosity and produce more oil. There are two main steam injection techniques - cyclic steam stimulation (also called huff-and-puff) which alternates between steam injection and production from single or multiple wells, and steam flooding which continuously injects steam into reservoirs to displace oil towards production wells. The document outlines some advantages and disadvantages of steam injection and economic considerations.

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2. Enhanced Oil Recovery
Steam Injection

3. What is Enhanced Oil Recovery (EOR) ?
• A generic term for increasing the amount of
crude oil extracted from an oil reservoir
• Also referred to as ‘improved oil recovery’ or
‘tertiary oil recovery’
• Using EOR, oil extraction rate can exceed up to
60% compared to primary and secondary oil
recovery methods (20-40% recovery)

4. Methods of EOR
• Gas injection methods
• Chemical injection methods
• Thermal methods
– Steam injection
– Fire flooding

5. Steam Injection
• One of the methods included in EOR
• Applies the use of steam for recovering oil
• Has several different forms but two main ones
– Cyclic Steam Stimulation
– Steam Flooding

6. Cyclic Steam Stimulation
• Also known as “Huff-and-Puff” method
• Sometimes applied to heavy-oil reservoirs
• Assists natural reservoir energy by lowering
viscosity of oil
• Commonly used for a formation of oil-wells but
can be applied to a single-well procedure

8. Cyclic Steam Stimulation (contd.)
• The cycle may be repeated until the recovery
response becomes minimum due to decrease
in pressure and increase in water production
• Accompanied by continuous steam-flooding to
continue the supply of heat and to replace
declining pressure of reservoir

9. Steam Flooding
• Most commonly used in heavy-oil reservoirs
having high viscosity
• High-temperature steam is continuously
ejected into the reservoir which,
– Loses heat to formation of water and condenses
– The hot water produced coupled with continuous
steam supply acts as a driving force to move the
oil to the production wells

11. Advantages
• Steam floods are easier to control than fire-floods
• Steam floods do not cause cracking of oil and no environmentally
objectionable flue gases are produced
• Steam injection wells are subject to much lower temperature than
fire injection wells
• Steam flooding can be applied to reservoirs containing high API
gravity oils
• Flushing of liners and casing perforations, as well as the reduction
of deposits that may build up in the wells

12. Disadvantages
• Heat losses are high through injection lines,
wellbores and oil well formation
• Steam flooding requires large supply of high
quality fresh water
• Steam injection can’t be performed at depths
below 5000 ft because of high reservoir
pressure

13. Economic Considerations
• Capital investment is lower
• Fuel consumption per barrel of oil produced is
higher

14. References
• http://en.wikipedia.org/wiki/Steam_injection_%28oil_i
ndustry%29
• www.netl.doe.gov/technologies/oil-
gas/publications/eordrawings/BW/bwsf.PDF
• www.netl.doe.gov/technologies/oil-
gas/publications/eordrawings/BW/bwcyclic_stm.PDF
• www.most.gov.mm/techuni/media/PE_05045_2.pdf