非均质底水油藏水平井ICD完井优化设计

流入控制阀(ICD)完井动态模拟预测和完井参数优化设计是ICD完井实现水平井生产优化的生命基础。结合半解析耦合模型和Eclipse 2011,建立稳态模拟和瞬态模拟相结合的ICD完井动态模拟方法。该方法不仅是以某一时刻的完井动态为设计依据,而是同时从整个生产周期内井筒与油藏流动动态最佳的角度来优化设计完井参数。针对非均质底水油藏,利用建立的模拟方法进行了ICD完井实例计算与参数敏感性分析,并分别提出了不同布置方式下的ICD完井优化设计方法。结果表明:ICD完井相对于常规完井能显著改善水平井的生产动态;ICD限流强度的确定需综合考虑产液剖面均匀程度和水平井采油指数,ICD完井存在一个最优ICD限流强度;对于非均质底水油藏,水平井ICD完井存在一个最优封隔器个数,其与具体储层的渗透率非均质程度密切相关;变化布置ICD完井设计相对于统一布置ICD完井设计不仅能使产液剖面更均匀,而且还能提高水平井的采油指数。

ICD completion optimization design of horizontal wells in heterogeneous bottom-water reservoirs

The performance simulation and prediction of inflow control devices (ICD)completion and the optimization design of completion parameters are the survival foundation of ICD completion to achieve the production optimization of horizontal wells. According to semi-analytical coupling model and Eclipse 2011, a dynamic simulation method of ICD completion was established by integrating steady-state simulation and transient-state simulation. This method not only takes the completion dynamics at a specific time as design basis, but also optimizes and designs completion parameters from the view of optimal wellbore and reservoir flow dynamics throughout the whole production cycle. Aiming at the heterogeneous bottom-water reservoir, the above simulation method was used for example calculation and parameter sensitivity analysis of ICD completion. In addition, the optimization design methods of ICD completion were put forward for different arrangement patterns. The result shows that ICD completion can considerably improve the production dynamics of horizontal wells compared with conventional completion. The determination of ICD flow-restriction sizes needs to consider the production profile uniformity and horizontal well productivity index comprehensively, and ICD completion is featured with the optimal flow-restriction sizes. For a heterogeneous bottom-water reservoir, ICD completion of horizontal well is featured with the optimal packer number, which is highly related with the degree of permeability heterogeneity for a specific reservoir. Variable ICD completion design not only further improves the production profile uniformity, but also increases the horizontal well productivity index compared with uniform ICD completion design.