Experimental study and modeling permeability damage in porous media due to asphaltene deposition

Abstract Asphaltene deposition in porous media has a destructive effect on well productivity during primary and secondary oil recovery. Previous research studies have presented models for permeability reduction due to particle deposition in porous media. In this study, a semi-experimental model was modified and a new model was introduced to predict permeability changes due to asphaltene retention in early times of precipitation. The modified model unlike common models considers the size of asphaltene particles, porous media grain size, fluid flow properties and precipitation in pore throat. A set of experiments are done to obtain the parameters needed for modeling and check the validity of model. Crude oil is used as fluid sample and a sand pack filled with glass beads is used as an artificial porous media in flood tests. To identify the size of asphaltene particles, microscopic technique is used. The results of experiments are used to investigate asphaltene deposition in porous media and evaluate model prediction. A new procedure based on the modified model is applied to obtain model parameters and simplify the calculations. The new model can eliminate the deficiencies in previous models for prediction of asphaltene deposition in early stages of particle retention. The model also is validated by experimental results that were reported in the literature before. The results show rational accommodation with experimental data.