Understanding and modelling the wettability of tight rocks is essential for designing fracturing and treatment fluids. In this paper, we measure and analyze spontaneous imbibition of water and oil into five twin core ...Understanding and modelling the wettability of tight rocks is essential for designing fracturing and treatment fluids. In this paper, we measure and analyze spontaneous imbibition of water and oil into five twin core plugs drilled from the cores of a well drilled in the Montney Formation, an unconventional oil and gas play in the Western Canadian Sedimentary Basin. We characterize the samples by measuring the mineralogy using XRD（x-ray diffraction）, total organic carbon content, porosity, and permeability. Interestingly, the equilibrated water uptake of the five samples is similar, while, their oil uptake increases by increasing the core porosity and permeability. We define two wettability indices for the oil phase based on the slope and equilibrium values of water and oil imbibition curves. Both indices increase by increasing porosity and permeability, with the slope affinity index showing a stronger correlation. This observation suggests that part of the pore network has a stronger affinity to oil than to water. We also observe that the two indices decrease by increasing neutron porosity and gamma ray parameters measured by wireline logging tools. The samples with higher gamma ray and neutron porosity are expected to have greater clay content, and thus less effective porosity and permeability.展开更多
Micromodel flooding is a cost-effective method to investigate enhanced oil recovery.In this study,we apply Lauryl Betaine as an amphoteric surfactant to the injected fluids into the micromodel and compare the results ...Micromodel flooding is a cost-effective method to investigate enhanced oil recovery.In this study,we apply Lauryl Betaine as an amphoteric surfactant to the injected fluids into the micromodel and compare the results with conventional EOR techniques such as water flooding,solvent flooding,and microemulsion flooding.First,we determined the optimal flow rate of injected fluid into the micromodel to represent fluid flow in the formation.Next,we did water flooding with varying salinities.Next,we did solvent flooding with two different ratios of solvents.Condensate and hexane are the solvents we applied.Next,we did surfactant flooding using Lauryl Betaine.Surfactant flooding tests are conducted using different salinity and surfactant concentration(Cs).Finally,we did microemulsion flooding.The results show that surfactant flooding at high salinity using Lauryl Betaine leads to highest oil recovery among all tested EOR methods.Besides,the results indicate that addition of Lauryl Betaine to the injected brine leads to higher breakthrough time(BT).展开更多
基金NSERC (Natural Science and Engineering Research Council of Canada) for supporting this work
文摘Understanding and modelling the wettability of tight rocks is essential for designing fracturing and treatment fluids. In this paper, we measure and analyze spontaneous imbibition of water and oil into five twin core plugs drilled from the cores of a well drilled in the Montney Formation, an unconventional oil and gas play in the Western Canadian Sedimentary Basin. We characterize the samples by measuring the mineralogy using XRD（x-ray diffraction）, total organic carbon content, porosity, and permeability. Interestingly, the equilibrated water uptake of the five samples is similar, while, their oil uptake increases by increasing the core porosity and permeability. We define two wettability indices for the oil phase based on the slope and equilibrium values of water and oil imbibition curves. Both indices increase by increasing porosity and permeability, with the slope affinity index showing a stronger correlation. This observation suggests that part of the pore network has a stronger affinity to oil than to water. We also observe that the two indices decrease by increasing neutron porosity and gamma ray parameters measured by wireline logging tools. The samples with higher gamma ray and neutron porosity are expected to have greater clay content, and thus less effective porosity and permeability.
文摘Micromodel flooding is a cost-effective method to investigate enhanced oil recovery.In this study,we apply Lauryl Betaine as an amphoteric surfactant to the injected fluids into the micromodel and compare the results with conventional EOR techniques such as water flooding,solvent flooding,and microemulsion flooding.First,we determined the optimal flow rate of injected fluid into the micromodel to represent fluid flow in the formation.Next,we did water flooding with varying salinities.Next,we did solvent flooding with two different ratios of solvents.Condensate and hexane are the solvents we applied.Next,we did surfactant flooding using Lauryl Betaine.Surfactant flooding tests are conducted using different salinity and surfactant concentration(Cs).Finally,we did microemulsion flooding.The results show that surfactant flooding at high salinity using Lauryl Betaine leads to highest oil recovery among all tested EOR methods.Besides,the results indicate that addition of Lauryl Betaine to the injected brine leads to higher breakthrough time(BT).
