Influencing Factors Analysis in the Combination of Gel Treatment and Low Salinity Water Flooding Using Sensitivity Analysis

摘要

Gel treatment is often used to control the excessive water production in fractured reservoirs. Combined technology has drawn a great interest in the oil industry over the last decade. Recently, gel treatment combined with low salinity waterflooding brought a significant attention in reservoir engineering. It has been reported that low salinity waterflooding can improve displacement efficiency. Gel treatment has been proved to plug fractures and improve sweep efficiency. The objective of this paper is to provide a deeper understanding of this combined technology by applying experimental and simulation approach (sensitivity analysis). The purpose of sensitivity analysis is to determine how sensitive the oil recovery factor obtained at different conditions to different parameters. The experimental results found that the low-salinity water can improve oil recovery factor by 6% and plugging efficiency was also improved. The sensitivity analysis results showed that the initial oil saturation, oil viscosity, porosity, and matrix permeability were the most important parameters affecting improved oil recovery when combined technology applied. The matrix permeability was the most important parameter impacting the obtained oil recovery, and the oil saturation was the lowest. The performance of using low-salinity water increased when matrix permeability increased, and porosity decreased. Identifying the parameters which have a significant impact on oil recovery would give a good prediction for combined technology success or failure depending on reservoir properties.