Cyclic Group Steaming of Wells (CGSW): A Case Study in Issaran Egypt Field

Abstract

This paper describes a case study of cyclic group steaming of wells (CGSW) in a heavy oil (10-12 API) field located in Egypt. The field is known as Issaran with approximately 1.2 billion barrels of oil in place. CGSW was implemented in a pilot in a highly fractured limestone reservoir, with highly permeable fractures. During cyclic steam injection in the pilot, a negative effect was noticed during steam injection in some wells on surrounding wells; the gross production rate increased accompanied by an increase in water cut and wellhead temperature leading to loss in oil production. This meant that steam injection strategy needs some modifications To avoid this, CGSW was implemented by applying steam cycles in all the producers of the pilots simultaneously, allowing for a better distribution of heat around all the wells.Cyclic steam injection of all wells together implies pressurizing the reservoir, and hence increasing the reservoir energy along with decreasing the oil viscosity and enhancing the ultimate oil recovery. This, together with eliminating the negative effect of steam injection from the neighboring wells allowed the wells to show a better performance Comparison is made between some of the wells producing before and after CGSW. The results are shown along with a full description of the process.