Evaluation Of Block-S6 Development Effectiveness And Study On Schemes Of Excavation Potential

This thesis focuses on issues such as rapidly dropping pressure,rapidly declining production and unclear distribution of residual gas in block-S6,bases on the static data and dynamic production data of block-S6,synthesizes seepage mechanics,gas reservoir engineering and gas reservoir numerical simulation,uses a disciplinary theory-combining gas reservoir engineering and numerical simulation,carries out gas reservoir development effect evaluation and tapping potential research projects.Firstly,evaluated the development effect indicators of gas well production capacity,declining production,dynamic reserves,etc.Secondly,established the 3D geological model and the numerical simulation model,analyzed the distributed characteristics of formation pressure and residual gas,identified the potential excavating capacity of blocks-S6.Finally,based on development effect evaluation and residual gas distribution law research,formulated 5 sets of tapping potential projects,predicted the main development indicators and economic benefits of each projects,optimized an optimal tapping projects.Through the study of this paper,the following results have been obtained:1.Average single well productivity is 7.44×10~4m~3/d calculated by Yuanqian Chen single point productivity formula and Changqing oilfield experience formula,calculated the reasonable production of individual wells using experience method shows that the initial gas reservoir and the current allocation are more reasonable.The decline of gas well productivity is analyzed by the method of Aprs decline curve.The law of gas well decline curve has a two-stage characteristic.The early decline curve decreases exponentially,and the late decline curve shows decreasing and decreasing or hyperbolic decline.The average single well dynamic reserves calculated by the production instability method and pressure drop method are 0.31×10~8m~3,and the average single well control radius is 178.2m.2.Established the 3D geological model and a numerical simulation model.The model analysis shows that the residual gas is mainly distributed in the northeast and middle parts of the gas reservoir and each small layer has a large potential for excavation.3.Recommend the optimal potential tapping project which have a total of 78 wells,including new 18 wells(17 vertical wells,1 horizontal well).Forecasted the stable production period of this project was 5 years,recovery percent of gas reserve was 36.96%,total cumulative production gas was 30.39×10~8m~3,FNPV of this project was 160.36 million CNY and FIRR was 16.89%.