Analysis Of Inefficient Factors And Study On Enhanced Oil Recovery Measurements In Qigu Formation Of H-1 Block

The reservoir of Qigu formation in H-1 block,which is located in he northwestern margin of the Junggar basin,is a lithologic structure heavy oil reservoir with medium porosity and permeability.It's proven reserve is 7 million 320 thousand tons while the using reserve is3 million 280 thousand tons.The degree of recovery was only 15.8% by May 2016.There was low development efficiency for the low production and high water cut.The main contents of this paper including the geological characteristics of the reservoir,the development of the reservoir and the analysis of the inefficient production factors.The characteristics of the reservoir,the structural features,the petrological characteristics,the physical characteristics,the sedimentary characteristics of the reservoir and geological elements of reservoir characteristicsare are systematically analyzed.The analysis provides detailed geological basis for the following study.From the block development history to the current production dynamics,In order to identify the main problems facing the current development of blocks,the author analyzes the history from the block development up to the current production dynamics.At the same time,showing the reasons of its formation and the factors of inefficient production.Through development performance analysis and numerical simulation,reservoir thickness and crude oil viscosity,huff and puff steam injection parameters,and development well pattern were ascertained as the main factors caused the problems in the area.Therefore,three methods were proposed to improve the recovery rate of the treatment scheme: A.injection production adjustment and parameter optimization of steam injection mode were put forward under the mode of the steam injection steam injection rate,steam injection intensity and injection pressure and optimization;improved steam injection mode,including combined steam injection,a dynamic and overlapping throughput mode area.B.steam channelingtreatment.The identification and description of steam channeling was studied respectively.So,the measurements could be taken as soon as possible to reduce the loss of steam channeling.C.well network encryption.Through the study of the current mode of steam injection heating radius and the cases of other encrypted blocks in Xinjiang oilfield,the adaptability and effectiveness of encryption were demonstrated.