Comparison of the chemical flood recovery efficiency via experimental studies on the Pre-Caspian Basin core samples

Abstract

This article examines the polymer and ASP flooding effects on the X field. Experimental studies were carried out on core material from heavy oil to compare the effectiveness of these methods. Core data as a sampling depth, porosity, permeability and core volume, as well as properties of reservoir oil and water were determined before filtration tests. At early stage of the study, an optimum composition of alkali-surfactant system for combined flooding has selected. At the second stage, type of the polymer and its optimum concentration has been determined, both for the polymer and for the ASP flooding methods. The one-concentration values have been used for a comparative analysis of the both flooding methods. At the final stage, the filtration tests have been performed on the PLS-200 unit for the comparative evaluation of polymer or ASP flooding efficiency. The studies represent increased displacement coefficient through both recovery methods. For this field, the maximum total displacement coefficient with a value of 0.68 unit fraction is achieved when a solution of both the polymer and the polymer in combination with surfactant and alkali solutions affect. However, the maximum displacement with coefficient 0.19 has been achieved by the ASP method.