Study on application of well selection method for staged production of offshore high water cut oil wells
The water body of offshore edge and bottom water reservoir has sufficient energy.Once water is seen in the production process,it will quickly enter the high water cut stage,seriously affecting the oil well productivity.At this time,it is necessary to select the oil wells suitable for staged exploitation,so as to achieve the purpose of re-straining high water cut and extending the oil well life through staged exploitation.Therefore,the sensitivity analy-sis of influencing factors of water cut rise is carried out by using the mechanism model of staged production,the basis of well selection method for staged production of high water cut oil wells is studied,and the numerical simulation method is used for verification.The results show that:1)Through the simulation of the mechanism of staged mining in the horizontal section,the mining effect of horizontal well development and the sensitivity relationship of the influ-encing factors of water cut rise are analyzed.The research shows that the order of the sensitivity of the influencing factors is:viscosity＞high-low permeability differential＞proportion of high permeability strip＞maximum liquid pro-duction＞permeability of high permeability section.2)According to the production performance,geological data of horizontal section and data of adjacent wells,the water breakthrough mode of high water cut horizontal wells in off-shore bottom water reservoirs is divided into linear full water breakthrough,point partial water breakthrough and multi-point full water breakthrough.The point partial water breakthrough mode can be exploited in sections.Taking typical well A1 as an example,the established well selection method and process can be used to judge that the water cut curve is linear water breakthrough,and the water cut in the well is high,The permeability of the horizontal sec-tion is characterized by obvious segmentation.The water flooded degree of sublayer Ⅲ-1 is relatively high,and the water flooded degree of the heel of well A1 is serious.The water flooded degree of the toe of well A1 is relatively low due to the shielding of the first set of interlayer.It is a local water flooded pattern of point water breakthrough,which is consistent with the characteristics of segmented mining.3)For the point shaped water breakthrough par-tially flooded horizontal wells,the staged exploitation is used to stabilize oil production and control water production.The numerical simulation method is used to simulate and predict that the oil production and recovery rate of the staged exploitation plan are significantly improved compared with those of the non staged plan,which verifies the ap-plicability of the well selection method and staged exploitation.The proposed well selection method flow can provide a method basis for the study of well selection for staged exploitation of horizontal wells in the field.
high water cuthorizontal wellstaged miningwell selectionsimulation analysis
NETL
NSTL
万方数据
维普
