Steam Stimulated Wells Gas Injection Orthogonal Optimization Design

The average viscosity of the heavy oil from Nine-7 Block of Karamay Oilfield at 20 ℃ is 4.52×105 mPa·s.Because of high viscosity,steam stimulation results were poor when the general steam simulation parameters were used.Therefore,steam injection parameters for Nine-7 Block were analyzed and optimized using orthogonal experiment design.The sensitivity analysis indicates that the parameters impacting the production results from high to low are production time,steam dryness,cyclic steam injection volume,steam injection pressure.The optimization parameters are production time 60d,steam dryness fraction 70%,cyclic steam injection volume 2 210 t,and steam injection pressure 4.0 MPa,stew time 3d,and steam injection velocity 220 t/d.The optimization results agree with the theoretical computation results.Through sensitivity analysis and the optimization results,very good results were obtained in Nine-7 Block,which can be used to guide the development of the extra or super heavy oil reservoirs.