The Effect of Surfactant-Bearing Fluids on Permeability Behavior in Oil-Producing Formations

Abstract

The Effect of Surfactant-Bearing Fluids on Permeability Behavior in Permeability Behavior in Oil-Producing Formations American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc. Abstract The use of surfactants during various types of fracturing and acidizing treatments on oil wells is a commonly accepted practice. It is known and has been verified by several laboratory studies that surfactants have a marked effect on formation rock permeability in the treated wells. During hydraulic fracturing treatments, for example, large volumes of surfactant-bearing fluids are pumped deep into the formation matrix through the created fracture system. This paper presents the results of an investigation of the behavior of fluid flow on formation core plugs that have been subjected to either aqueous base fluids or hydrocarbon fluids containing various types of oil-wetting or water-wetting surfactants. Guidelines as to the most efficient types of workover fluid and surfactant combinations for maintaining hydrocarbon permeability are indicated from the data obtained. A method of "water-block" removal and restoring formation hydrocarbon permeability has also been observed permeability has also been observed and is discussed in this paper. Introduction When a fluid is pumped into a semistable environment such as a petroleum reservoir, vast changes in fluid saturations can occur in the area where the encroaching fluid is in contact with the formation and the formation fluids. The fluid pumped into the reservoir may be a fracturing fluid or some other type of workover fluid and may be an aqueous or hydrocarbon fluid. The presence of the fluid can cause changes in the permeability and flow behavior of the formation. Due to the wide ranges and various types of fluids that are used in oil wells, the investigations discussed in this paper will be primarily related to fracturing fluids. primarily related to fracturing fluids. When a hydraulic fracture is produced in a formation, a breakdown or produced in a formation, a breakdown or actual parting of the rock occurs.