Use Of Flow Control Devices For Uniform Steam Injection In SAGD Horizontal Well Completion

With the development of the global economy,the world's demand for oil and gas is increasing,and heavy oil resources are attracting more and more attention with its abundant reserves.The Steam-assisted gravity drainage(SAGD)is currently the most advanced and promising enhanced oil recovery technology for producing heavy crude oil and bitumen,with high efficiency and cost-effectiveness.And as the horizontal well drilling and completion technology develops,steam injection along horizontal wells has been widely applied in heavy oil production.However,due to friction and other factors,there is a problem of uneven steam injection,which reduces the utilization degree of oil reservoirs and negatively affects the productivity of the horizontal wells.In recent years,researchers have optimized the completion of SAGD well by using flow control devices(FCD),which can achieve balanced steam injection and improve producing efficiency.In China,however,relevant technologies have been scarcely applied in field operations.Therefore,considering the complexity of SAGD process and its huge potential,it is necessary to conduct research on using FCD for uniform steam injection in SAGD horizontal wells.In this thesis,numerical simulation method was used for building 3D geological models,mechanism models,and wellbore coupling models,simulating SAGD production and development of the steam chamber.Taking Z32 Field in Xin Jiang as an example,based on characteristics of its heavy oil reservoir,this thesis studied the optimized SAGD horizontal well completion design.Through research and analysis,research results can be summarized as below.1)Results showed that producing performance of SAGD was influenced by various factors,including heterogeneity of reservoir,interlayer insulation,water layer,gas top,etc.Through sensitive analysis,it can be concluded that with more FCDs being closer to the wellbore,the steam chamber tended to grow more uniformly and steam breakthrough was delayed.2)For the nozzle type FCD,the smaller the aperture,the greater pressure drop and better flow control can be achieved.With the design of proper quantity and installation of FCD,the SAGD horizontal well completion can be optimized.3)According to the case study,results showed that the production rate of SAGD with FCD was higher than that without FCD by 20%,which proved the important role that FCD plays in improving SAGD producing performance.This thesis put forward the idea of optimizing the well completion of SAGD horizontal well by using FCD,thus providing theoretical foundation and reference for related research of heavy oil reservoir development in the future.