Displacement Theory Part 1 PDF

Displacement Theory Part 1 Secondary and Tertiary Oil Recovery Agenda  Capillary number  Wettability  Relative permeability curves  Drainage and Imbibition Capillary Pressure Curves Capillary Number Capillary number (Nc) = Viscous forces/capillary forces = µv/σ µ = viscosity in cp V = Darcy velo...

Displacement Theory Part 1 Secondary and Tertiary Oil Recovery Agenda  Capillary number  Wettability  Relative permeability curves  Drainage and Imbibition Capillary Pressure Curves Capillary Number Capillary number (Nc) = Viscous forces/capillary forces = µv/σ µ = viscosity in cp V = Darcy velocity of displacing fluid σ = Interfacial Tension Higher the Nc, lesser would be Sor in the reservoir Reduction in Sor requires ultra lower interfacial tension by surfactants, miscible gas injection and/or very high pressure gradient by viscous polymer to overcome strong capillary pressure Nc = µυ/σ Typical Waterflooding Nc 10-7 to 10-6 Capillary Number How viscous is the oil? Viscous forces Viscous forces arise due to internal friction among molecules of moving fluid and external friction with solid and other phases It is defined as pressure gradient i.e pressure drop / unit length, which is proportional to viscosity and velocity of moving fluid Wettability Wettability and Relative Permeability relationship Relative Permeability Functions Effect of Wettability for Increasing Sw You can use the information from Relative Permeability functions to calculate what is your Displacement Efficiency (ED) value is by using the equation below. 𝑆𝑆𝑜𝑜𝑜𝑜 − 𝑆𝑆𝑜𝑜𝑜𝑜 𝐸𝐸𝐷𝐷 = 𝑆𝑆𝑜𝑜𝑜𝑜 Drainage and Imbibition Capillary Pressure translated to height Effect of Permeability Effect of Gravity Capillary Pressure translated to height Holistic Review: Capillary Pressure Curves Next Class Displacement Theory Part 2