Introduction

Abstract

In view of the world-wide shortage of petroleum and the fact that almost 65% to 70% of original oil-in-place is left in the reservoirs at the end of waterflooding, the importance of tertiary oil recovery methods to produce additional oil can hardly be overemphasized. The enhanced oil recovery methods can be divided in two major groups, namely, thermal processes and chemical flooding processes. The in situ combustion, steam injection, wet combustion, etc., fall in the first category whereas the caustic flooding, surfactant flooding, micellar-polymer flooding, CO₂ flooding, etc., fall in the second category of processes.