Research On The Theory And Related Tool For Water Control Completion Of Horizontal Well

Horizontal well,as a efficient way with high production,has been widely used for thin oil reservoir,bottom water reservoir,fractured reservoir,heavy oil reservoir,marine oil reservoir,and unconventional oil reservoir.But there are a few problems of horizontal well during the production process,especially for the bottom water reservoir,that show mainly the fast water cresting results in well water cut increased and it’s difficultly to detect and plug water in horizontal well by current techniques,which has been a serious restriction on horizontal well development.Therefore,based on the previous studies of bottom water cresting and water control methods,a new tool for water control was designed and the correspongding horizontal well completion theory was researched to solve the technical problems and practical issues.In view of the multiple types of AICD on the former literatures and the present wells situation of high water cut in china,a new AICD—automatic phase selection controller(PSC)was designed.The flow field,the fluid sensitivity,the erosion and the ability of water control were analyzed concretely and the pressure drop comparisons with ICD were carried out by CFD software.The results indicated that:the PSA was able to improve oil flow and restrict water and gas flow more efficiently than ICD;it was availably to resist erosion and be applied in the wide viscosity and flow rate range rarely influenced by the fluid density.The experiment on single and two phase flow for different fluids via the PSC was performed to verify the validity and the results were compared with CFD simulation to build a model of the pressure drop for single PSC.To research the impact of different numbers and distribution of the tools on water control for the horizontal well in bottom water reservoir,a 3-D two phase model of horizontal well completion with the APSC was deduced by coupling the seepage in the reservoir and the pipe flow in the well(include the base pipe flow,the annulus flow and the flow via the PSC),considering the permeability heterogeneity and anisotropy,the damage of drilling,the well track and so on.Then,on the basis of the above model the performance of horizontal well completion with the PSC was simulated dynamically in different completion parameters respectively for typical homogeneous reservoir,heterogeneous sand reservoir and fractured carbonate reservoir.The results showed that the PSC improved the production statement of horizontal well obviously by equilibrating the profile of oil and water,prolonging the period of water-free oil production,reducing the water cut and increasing the accumulated oil production which had more advantages over the conventional completion.The simulated performance of the PSC completion in different parameters was analyzed to derive the influence law on each other which was helpful to form a method system of the optimization design for the PSC completion in horizontal well.Finally,applying the PSC completion to the actual horizontal well,the corresponding completion design was used in the bottom water reservoir.The comparisons of well production performance between the pre-and post-PSC completion were made to testify the effectiveness of the tool and the reliability of the completion design theory.With theory analysis,experiment research and actual test,in this thesis the development and study of the completion tool for water control in bottom water reservoir can provide the technical and theoretical support for high production of horizontal wells,and lay the foundation for the popularization and application of this technology in domestic and forming the core service ability of the independent intellectual property rights,which have significant theoretical and practical value.