Formation Damage Kinetics and its Effect on Oil Reservoir Productivity

Abstract

Abstract Formation damage, a common problem associated with field operations, is often a major factor in reducing the productivity and injectivity of a well in a petroleum reservoir. Numerous laboratory and field studies indicate that formation damage occurs during many phases of reservoir development – drilling, completion, workover, production, stimulation, water flooding, or improved oil recovery. Formation damage is a process of initial permeability reduction. At present many mathematic formation damage models are developed. These models contain a number of parameters that is difficult to determine and mostly are not appropriate for field usage. We offered a way from lab to field scale that takes into account the process of formation damage during reservoir development. Analyzing the results of laboratory experiments and formation damage studies we defined that permeability has similar kinetics of alteration for different damaging mechanism. Next we determined the principal damaging mechanisms of real oil formation and associated them with laboratory relations of permeability alteration. As a result the integrated relations of permeability reduction and the new model of formation damage were obtained. This method was used as a predictive tool for quantitative predictions of field development showings for different rock types and operation strategies. Equations of permeability kinetics were integrated into reservoir simulator. The effect of permeability kinetics on formation development process was shown concerning clay oil formation. Based on laboratory and field observations the methods of enhanced oil recovery and formation damage prevention were proposed.