Abstract
Steam assisted gravity drainage (SAGD) process has been widely used commercially in Western Canada for bitumen production. Improving oil production rate and reducing steam oil ratio has been the focus of the industry. In heterogeneous reservoirs, oil production could be impeded by local steam break through and high liquid level above the other section of the producer. Various completion methods have been proposed to improve production efficiency. Steam splitter is proposed to match steam delivery to reservoir requirement and scab liner may be used in producer to maximize oil production. In general, oil drainage into producer may need to be slowed down at some locations and speeded up at other locations of the well. Non-uniformity of the reservoir pay and quality also has a direct impact on oil production and consequently, it is significant to divert required amount of steam to the desired spots of the reservoir. In this study, we address how to design steam splitter and scab liner in order to optimize SAGD production. Results from reservoir simulation with coupled wellbore hydraulics will be presented to show how a wellbore could be optimized by attaining favorite pressure profiles inside the injector and producer liners. This investigation will also address sensitivities on steam splitter location, size and number of holes in splitter, and size and length of scab liner.
