Optimization Design Method Of Water Control And Sand Control Completion In Horizontal Wells

With the development of horizontal well drilling and completion technology,horizontal wells are widely used in various types of reservoirs and have achieved good development results.However,the increased wellbore length also leads to some problems that mainly display imbalanced water breakthrough time(sanding onset will be aggravated during water cut stage)and production pressure drop along the wellbore which is caused by the heel-toe effect,heterogeneity of reservoir and the difference distance between wellbore and water-oil contact.Thus,the bottom water coning and sanding along the horizontal section have a strong heterogeneity,resulting in earlier water breakthrough and large amount of sand production,which seriously affects the productivity and comprehensive benefits of horizontal wells.The ICD completion have proved to be of the ability to mitigate the imbalanced inflow,to achieve effect of delay bottom water coning and controlling the reservoir sand production.Since no design method of ICD completion is available for sand control together with water control in horizontal wells.Thus,it's necessary to make segmentation method and ICD parameter optimization research on sand control and water control.Firstly,on base of potential superposition theory and method of mirror,the coupled model of wellbore and reservoir flow has been built,which take into consideration reservoir properties and completion technology.Then,sensitivity analysis of factors causing uneven production in horizontal wells have been finished.Secondly,this paper takes into consideration the influences of reservoir properties heterogeneity,the heel-toe effect and the different distance between wellbore and water-oil contact on sand production along the horizontal well.Then,the critical drawdown pressure of sanding onset and water breakthrough time in each micro section are calculated based on the calculation model of sanding and prediction model of water breakthrough time.After that,the critical drawdown pressure of sanding onset and water breakthrough time of each micro section are selected as segmentation indexes,and multi-dimension sequential clustering method is introduced.The segmentation method for sand control completion together with water control in horizontal wells is establishedFinally,the ICD completion is chosen as the object of study,and controlling sand production is chosen as constraint condition,the number of ICD and the size of the nozzle are used as the design variables.Then,a multi-objective optimization model is proposed,aiming to maximize the oil production and water breakthrough time.The Non-dominated Sorting Genetic Algorithm-?(NSGA-?)is employed to obtain the optimal ICD completion parameters considering the effect of water control and sand control.In this paper,an optimization design method of water control and sand control completion in horizontal wells is developed,which includes a segmentation method for horizontal wells and ICD completion parameter optimization design.Then,a case well is analyzed by this method.The results show that the method can effectively play the role of water control and sand control in horizontal wells.