Study On Water Flooding Rule During The Extra-high Water-cut Stage Using Large Physical Model

Sandstone reservoir for water flooding in Shengli oilfield has been in the stage ofextra-high water cut now. The development rule shows new changes. Extra-high water cut isan important development stage, and the large amount of recoverable reserves will berecovered in this stage. So the percolation mechanism in this stage should be studied toimprove the EOR.This paper shows the study of water flooding mechanism using large3D physical modelin the extra-high water-cut stage. The small core experiment has the disadvantage of modelsize and measuring accuracy, which have bad influnce on the experiment result. Meanwhile,the3D model can model the water-flooding features on the different the rhythmicity and wellpatterns.The key point of the model study is modeling the pore structure of naturalrock,rhythmicity feature,the mercury penetration and oil-water relative permeability curvessimilarity between natural reservoir and the model.The large-scale models with differenthomogeneity and heterogeneity. In addition, the new technique fitting for monitoring of thistype model is studied to test model and modeling test.The paper also studies the saturated oil features in3D model.The study establishes thesaturated oil method of heterogeneity model.The four-injector and one producer waterflooding model is developed using large physical modeling technique to obtain the recoverydegree in equilibrium displacement and non-equilibrium displacement during differentdevelopment stages.