Title: Foam for mobility control in alkaline surfactant EOR process
1Foam for mobility control in alkaline surfactant
EOR process
- Wei Yan
- George J. Hirasaki
- Clarence A. Miller
2Outline
- Bulk foam apparent viscosity in fractures
- Foam stability with the presence of residual oil
- Salinity and Calcium tolerance of NI blend
- Alkaline-surfactant-polymer-foam flooding in
vertical silicone sand pack
3Bulk foam at medium to low gas fractional flow
Water
4Model for bulk foam apparent viscosity
Crowding factor
Viscosity of continuous phase
Internal circulation factor
Viscosity of dispersed phase
5Pals Model matches the experimental results for
bulk foam apparent viscosity
6Short pack device for foam stability
7Foam stability test results
8NI Surfactant Blends Improve Salt Tolerance
Cloudy after 9 months.
9NI Surfactant Blends Improve Calcium Tolerance
10Experimerntal conditions for ASPF in sandpack
Flow direction Vertical
Surfactant concentration 0.2
Surfactant composition N67-7POIOS (41)
Polymer concentration 0.35
Viscosity of polymer 47 cp
Salinity 2 NaCl, 1 Na2CO3
Temperature 24 C
Oil viscosity 19 cp
Residual oil saturation 25
Superficial velocity (ft/day) 5
Recovery efficiency 98
11Experimental procedure for ASPF flooding
- Fill the sand pack with crude oil
- Brine flood until no oil comes out
- Na2CO3/NI-blend/Polymer flood for 0.5PV
- IOS/Polymer flood for 0.2PV
- Foam (fg 0.67) flood as drive
12(No Transcript)
13ASP Experiment in 40 darcy vertical silica
sandpack
14Effluents for different pore volume for ASPF
experiment
15Conclusions
- Bulk foam apparent viscosity at medium to low gas
fractional flow can be described by
semi-empirical model. - IOS is a good foamer with the presence of
residual crude oil - NI blend can improve the surfactants tolerance
to calcium and salinity - Foam drive can be used to replace polymer drive
in alkaline-surfactant-polymer process