Simulation Study of Fractures Geometrical Parameters Effect on Steam Assisted Gravity Drainage (SAGD) Performance

Simulation studies of the SAGD process were made on different fractured models with fractures in both Near Well Region (NWR) and Above Well Region (AWR) and in networked fractures. At early stage, steam moves through the fractures first and then the matrix blocks are heated primarily by conduction and possibly some steam invasion. The steam-oil interface forms and develops from all sides of the matrix and oil chamber rather than a steam chamber forms and shrinks in the center of each block. SAGD process recovery enhanced in the presence of vertical fractures but horizontal fractures were harmful on the recovery. Fracture spacing was not a very important parameter in the performance of steam processes in fractured models. High fracture frequency improved SAGD performance since it reduced the time period necessary for heating the matrix block and enhanced heating process by conduction. Horizontal fractures between injectorproducer wells had an insignificant effect on the process since SAGD production mechanism is based on steam chamber development in AWR rather than NWR. Horizontal fractures extension increase reduced ultimate oil recovery. In the networked fracture model the presence of vertical fractures improved the recovery. Further effect of vertical fracture communications has been studied.

کلیدواژه ها:

EOR ، Fractured Reservoir ، Heavy Oil Recovery ، Process Simulation ، SAGD