A Newly Developed Mathematical Model to Predict Hydrolyzed Polyacrylamide Crosslinked Polymer Gel Plugging Efficiency in Fractures and High Permeability Features

Reservoir heterogeneity is one of the most challenging problems facing the hydrocarbon industry nowadays. It results in excess water production and a substantial reduction in oil recovery from water flooding applications. Gel treatment is one of the most successful applications to overcome reservoir heterogeneity problems by plugging high permeability features in a reservoir. One of the most widely used gels is the Hydrolyzed Polyacrylamide-Chromium Acetate Gel (HPAM/CrAc). This research uses data from 70 sources, including more than 1050 experiments, to perform a thorough data analysis to understand the conditions under which this gel is mainly applied. Histograms, and boxplots were generated revealing the ranges under which this gel can be applied, and the frequency of each range. The histograms and boxplots are each divided into the gel properties, and the core and sand pack properties, thus revealing both the chemical and rock properties' ranges. Three dendrograms were also developed based on their equivalent cluster plots generated. The dendrograms can show the different ranges at which the data was distributed and also tell the extent to which each range is related to the other. A mathematical model was also generated and validated in this study. This model gives a relation between the polymer concentration and the oil residual resistance factor (Frro). This model is extremely important since it can predict the effect of polymer concentration on the reduction of the oil permeability, which can help avoid the excessive reduction in oil permeability. The gel was found to have very good disproportionate permeability reduction (DPR), which indicates that it can reduce the permeability of water much more that the permeability of oil. This research can help in revealing the conditions under which the HPAM/CrAc gel can be applied, which in turn can significantly improve the design of field projects.