The Effect of Different Hysteresis Models On Water-Alternating-Gas (WAG) Process

• Main Author: Jusvir Singh, Amandeep Kaur
• Format: Final Year Project
• Language: English
• Published: Universiti Teknologi PETRONAS 2009
• Subjects: TP Chemical technology
• Online Access: http://utpedia.utp.edu.my/9165/1/2009%20-%20The%20Effect%20of%20Different%20Hysteresis%20Models%20on%20Water-Alternating-Gas%28WAG%29%20Process.pdf; http://utpedia.utp.edu.my/9165/

Enhanced oil recovery (EOR) or tertiary recovery is vastly applied to mostly mature and depleted oil reservoirs nowadays. One of the many EOR techniques is the Water- Alternating-Gas (WAG) process whereby water and gas are alternately injected for periods of time to provide better sweep efficiency hence improve oil recovery. !t is well known that whenever the fluid saturations undergo a cyclic process, relative permeability display hysteresis effects. Recent studies have been done on establishing the effect of hysteresis on WAG process. However, different hysteresis models will have different assumption and methods which eventually affects the production profile and recovery of an oil field. The main objective of this project is to quantify the effect of different hysteresis models (Carlson and Killough's model) on a conceptual model using black oil simulation. In addition to the main objective, sensitivities studies on the model without hysteresis were done to obtain optimum values prior to running the model with hysteresis. Hysteresis effect always results in higher oil recovery and oil production rate compared to the model without hysteresis. The quantification of both the hysteresis models shows that Killough's model results in higher oil recovery compared to Carlson's model. This is due to the fact that Killough uses particular equations to produce the scanning curve where else Carlson's scanning curve is produced by shifting the imbibitions curve horizontally until it cuts the drainage curve at the maximum nonwetting phase saturation. The way the scanning curve (intermediate imbibiton curves) is generated differs in both the models. This quantification of different hysteresis models can help in obtaining more precise prediction of forecasting oil recovery in the future. in