Study On Supporting The Development Of Horizontal Well Technology

In order to explore the feasibility of potentiality finding remaining oil in top area of Sabei development area, a height reservoir and currently in extra high water cut development stage, research of some auxiliary oil and gas field development techniques with horizontal wells were carried out. These key techniques include horizontal well bore tracking design, casing perforation optimization, productivity forecasting and well pattern tracking and modification. Accurate geologic model of this area has been established based on both dynamic and static materials. With the aborative description of geologic model, the model precision in vertical grid reaches sedimentary units. The intrastratal lithologic character fine model building technology was used to characterize the reservoir, and I divide Sabei reservoir zone into seven different lithostratigraphies in terms of reservoir properties and the growing position inner the reservoir. The impact of heterogeneous on development efficiency with horizontal well in Sabei area can be studied with this accuracy geologic model, and provide reliable basis for horizontal well bore tracking design. According to the development level of Sedimentary units'interlayer, the geological model was upscaled based on classifying and merging the vertical grids. The intercalated beds, higher than 0.2 meters, were reserved which not only ensures the accuracy of geological model but also satisfy the requirement for numerous reservoir simulation. The fluids flow performance in well bore was characterized by discreting the horizontal well into several segments by means of horizontal well bore track and shot phasing. The lithofacies were used to restrict the model vertical conductivity, depicting the fluids flow performance inside the sedimentary union and setting the flow boundaries. The girds closed to wells were refined, which increases the speed and accuracy of simulation model. This refined grids system extends numerous reservoir simulation for horizontal wells, guiding horizontal well bore location optimization, casing perforation design, production tracking and operation modification. The above techniques have been widely used in designing well bore tracking, casing perforation, casing direction, casing density, productivity forecasting and transferring artesian flow to pumping time for well Bei 5-8-Ping 53. The agreement between simulation results and production data up to 90.22% during the early stage of development, the prediction error of oil rate is 0.931% after 1 year's production. When the water cut reaches about 30%, it is the best time for putting on pump. The productivity forecasting models for two phases flow of horizontal well before and after water breakthrough have been established by applying reservoir engineering methods, and the accuracy of simulation is around 90.00%. The cumulative oil production of well Bei-5-8-Ping-53 is 1.75×10~4t and its oil recovery is up to 42.75 when the water cut reaches 98%. The composite water cut keeps below 10% for one year by applying the above horizontal well techniques horizontal well products oil with nature energy. After put on pump, the composite water cut is down from the 58.9% to 53.9% by sealing off the bottom of reservoir with long rubber tube, which based on the results of streamline simulation. Currently, the development effect of well Bei-5-8-Ping-53 is well, with 8030t fluid production and 5739t oil production. The result of my work can give effective guidelines for developing Sabei reservoir during extra high water cut with horizontal well, which is of significant means for oil field water controlling and sustainable development.