熵权密切值法完井方式优选模型的建立及在荔湾3-1深水气田的应用

The establishment of the entropy weight osculating value well completion method optimization model and the application in LW3-1 deep water gas field

深水气田开发高投入、高风险,完井方式的选择直接影响其开发的整体效益。为优选出适合深水气田的完井方式,综合考虑初始产气量、累计产气量、完井成本、财务净现值、动态投资回收期、防砂效果和施工风险等7个影响因素,将多目标决策密切值法与熵权法结合,建立了深水气田完井方式优选模型。以荔湾3-1深水气田某定向井为例,对深水气田常用的裸眼、裸眼砾石充填、套管压裂砾石充填、套管微压裂砾石充填和裸眼下高级优质筛管等5种完井方式进行了优选分析,结果表明该定向井最优完井方式为套管压裂砾石充填,与荔湾3-1深水气田2口直井、6口定向井实际生产情况相吻合,说明本文建立的熵权密切值法完井方式优选模型具有较好地推广应用价值,可为深水气田完井方式优选提供指导。

The choice of well completion methods influences directly the total benefits of the exploitation of deep water gas fields, due to high investment and high risk. In order to choose the optimized well completion meth- ods for deep water gas field, well completion method optimization model is established by combining the oscu- lating value method and the entropy method and considering 7 affecting factors comprehensively, the initial production, cumulative production, well completion costs, financial net present value, the dynamic payback period of investment, the effect of sand control and accident risk. Five well completion methods commonly used in deep water gas fields （open hole, open hole gravel pack, cased hole fracturing gravel pack, slight cased hole fracturing gravel pack, stand-alone sand screens） are analyzed for a directional well in LW3-1 deep water gas field. The result shows that the optimal well completion method for the directional well is cased fracturing gravel pack, which in line with the actual situation of 2 vertical wells and 6 directional wells. This suggests that the entropy weight osculating value method has better application value and can be used as guidance for optimization of well completion method for deep water gas fields.