A microsphere with the property of self-gathering was introduced.
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The pressure behaviors at different injection distance during microsphere injection were analyzed.
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The matching permeability for microsphere size was confirmed based on the injection and plugging abilities.
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The effect of profile control by microsphere injection in the heterogeneous reservoir was evaluated.
Abstract
Profile control in heterogeneous reservoir is an improtant work after water breakthrough. The particle systems have the advantages of less dosage and good controllability compared with the polymers, gelling systems, foams and so on. In order to evaluate the effect of profile control in heterogeneous reservoir, a microsphere system with the self-gathering ability is introduced in this work. The static properties related to the injecting and plugging abilites are also described. The dynamic behaviors during microsphere injection and plugging in porous media are discussed by the homogeneous core experiments, the experimental cores have the permeability ranging from 2.05 mD to 2025.94 mD. The effect of profile control by microsphere injection is analyzed from the heterogeneous core experiment. The results show that the microsphere has the properties of good dispersibility, high thermostability, microdilatancy and self-gathering, which are benefit to the microsphere injectiin and plugging. The analysis of injection pressure, injecting distance and residual resistance factor indicates that the microsphere with the average diameter of 100 nm has the good injecting and plugging abilities in the cores with the permeability ranging from 295.43 mD to 708.41 mD. The microsphere has the good profile control ability in heterogeneous core as it can be retained in high permeability layer, enlarge the sweep volume of subsequent water and improve the oil recovery. The self-gathered microsphere could be an efficient technology for profile control in heterogeneous reservoir.
