Optimistic Approach to Control Arc Stability in Unconsolidated Sands by Downhole Emulsification

Abstract

Abstract Production of heavy oils from Egyptian unconsolidated sand reservoirs causes sand production. It was proposed to use the Downhole Emulsification technique to control arc stability in the unconsolidated sand formations. The Downhole Emulsification was proved to be a significantly effective operational technique to handle sand production. The process involves the injection of an aqueous non-ionic surfactant solution into the well-bore to convert the water/oil emulsion to oil/water emulsion retaining at the same time sand within the oil phase. In the present work, a physical model was designed to simulate the sand production process. Then the rheological properties of oil/water and water/oil emulsions containing sand were measured at the reservoir conditions. The stability of the emulsions and sand accumulation rate were also examined under dynamic conditions. Sensitivies to water/oil ratios, surfactant concentrations, sand production rates, and different crude oils were performed in this study. Results were consequently used to optimize the composition of the aqueous surfactant solution, flow rate and settling velocity that guarantee a successful Downhole Emulsification process to keep sand in oil phase, hence control arc stability. The paper presents three case histories indicating very promising results.