Overview of the process and also review of literature

1. MISCIBLE NITROGEN
INJECTION
PRESENTED BY:
OLAYIWOLA, TESLIM OLAKUNLE
(40454)
Department of Petroleum Engineering,
African University of Science and
Technology.
DATE: 23rd June, 2017 1

2. OUTLINE
➢ Overview
➢ Why N2?
➢ Screening criteria
➢ Working principle
➢ Literature review
➢ Drawbacks and Solutions
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3. Overview
➢ Roles of reservoir engineer
• Improving the amount of recoverable reserve
• maximize production
➢ Recovery mechanism
• Primary recovery(12-15% RF)
• Secondary recovery (plus 10% RF increment)
• Enhanced Oil Recovery e.g. N2 injection
➢ Why EOR?
• High drilling cost
• High unrecoverable reserve
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4. Why N2?
➢ Availability and Economical
➢ Non-corrosive
➢ Friendly to environment,
➢ Less compressible than CO2 (most common)
➢ Vaporizes the lighter components of crude oil
➢ Nitrogen can provide a gas drive.
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5. Screening Criteria
➢API gravity: >35 API
➢Depth: Greater or equal 5000 ft
➢Rich intermediates
➢Viscosity: 0.4 cp
➢Formation: Sandstone and Carbonates
➢Temperature: Not critical
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6. Working Principle
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7. Literature Review
➢Alcocer et al. (1984)
•Studied the effect of temperature and GOR on RF
and Miscibility process
• Fixed API but varied temperature and GOR
•Found that RF and Miscibility depends on
Temperature and GOR
➢Rushing et al. (1976 – 1997)
•Studied the Effect of N2 injection pressure on oil
recovery
•Observed that Lighter crude with some gas has
better RF using high pressure Nitrogen injection
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8. Literature Review(Continued)
➢Paterson 1978)
•Performed laboratory experiment on oil recovery
by nitrogen at a particular temperature and
varying pressure
•Found that MMP of N2 = MMP of flue gas
➢Jensen(2000)
•Studied N2 injection using WAG process in
Ekofisk field after Water flooding
•Concluded that N2 can vaporize intermediate up
to C8
•No hydrates formation unlike CO2
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9. Drawbacks and Solutions
Drawbacks
➢Gravity Override
• Huge Density
difference
➢Viscous fingering
• Adverse Mobility
ratio
Solutions
➢Water alternating gas
(WAG)
➢Simultaneous WAG i.e.
SWAG
➢Modified SWAG i.e.
SSWAG
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10. REFERENCES
• Falade (2017). Enhanced Oil recovery class note, AUST
• Department of Energy DOE report, 2008
• C.F. Alcocer and D.E. Menzie: “Enhanced Oil Recovery by
Nitrogen Injection: The Effect of Increased Temperature and the
amount of Gas in Solution” SPE/DOE paper 12709 (April 1984).
• T. Jensen, K. Harpole, and A. Østhus. “EOR screening for Ekofisk,”
in Proc. European Petroleum Conference, 2000.
• Peterson, A.V.: "Optimal Recovery Experiments with N2 and C02,"
Petroleum Engineer, (Nov.l978)
• Rushing, M.D. "High-Pressure Air Injection," Petroleum
Engineering (Nov. 1976)
• Rushing, M.D. et al: "High-Pressure Nitrogen or Air May be Usea-
for Miscible Displacement in Deep, Hot Oil Reservoir," SPE Paper
#6445 (April 1977)
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