The Study Of Prediction Of Water Coning And Decision-making Technique For Water Shutoff For Bottom-water Reservoir

The water shutoff technique has become an important means for improving oil recovery and has been widely used. The decision-making technique for water shutoff was studied to instruct the exploitation.The model that supposes the radial-flow changes into spherical flow under the wellbore instead of spherical-flow were used to describe the flow condition from drainage area to wellbore. It is supposed that there are two kinds of boundary condition. On the basis of the theoretic model, the critical rate and the production before water breakthrough and the shape of the cone were calculated. Secondly the model used to describe the flow pattern after water breakthrough was founded. It could be used to describe the shape of the water cone. Finally the model with man-made barrier was set up. The influence on the production and shape of the cone was estimated.On the basis of the model, the software used for decision-making for water shutoff was completed. It could be used to optimize the penetration interval and predict the cone condition. It could determine the depth and radius of the barrier and predict the effect of the man-made barrier.