APPLICATION OF THE SAGD TO IRANIAN CARBONATE HEAVY OIL RESERVOIR

Steam injection is the most important thermal enhanced oil recovery method and in this method Steam Assisted Gravity Drainage (SAGD) is a very promising recovery process to produce heavy oils and bitumen. The method ensures both a stable displacement of steam and economical rates by using gravity as the driving force and a pair of horizontal wells for Injection/production. SAGD in Sandstone heavy oils Reservoirs has been characterized very well over the last years. However, there is much huge carbonate heavy oil in the world which their production can be enhanced by thermal recovery processes especially by steam injection. In this study, Application of SAGD to an Iranian heavy oil carbonate reservoir with low permeability has been investigated. Field-Scale 3-D and simulation models were constructed by using commercial softwares and by thermal simulators to investigate SAGD performance in this reservoir. The model was further applied to a fractured system and effects of fracture and matrix permeability, fracture to matrix permeability ratio, presence of week and strong aquifer on the performance of SAGD process were studied. By comparison with other thermal methods results showed that SAGD can be used as a best EOR method for this deep medium carbonate reservoir.