Investigation on Alkali-Surfactant-Foam (ASF) for Enhanced Oil Recovery, Experimentally and Theoretically

This thesis presented an extensive study on various aspects of ASF flooding process for EOR. It provides insight into hybrid EOR processes that are of a combination of immiscible gas and chemicals injection in sandstone reservoir. We wanted to discover the mechanism of oil displacement by ASF flooding in terms of 1) formation of oil bank, 2) transport of dispersed oil, and 3) movement and pushing of oil bank and dispersed oil by foam. The main premise of this thesis is whether immiscible foam flooding as an EOR technique can be improved by ASF flooding by a combination of the mechanisms of ASP EOR and Foam EOR methods? The first part of the thesis, chapters two and three, is devoted to numerical simulation and mechanistic modelling of the Foam flooding EOR process and the ASP flooding EOR process. Knowledge obtained from these two chapters formed the basis for further study of the behavior of foam in bulk and porous media in the presence of oil. The second part, chapters four to six, is based on the systematic laboratory experimental study of ASF EOR in the bulk and in the consolidated porous media conditions, and subsequently proposing a novel chemical EOR approach. Below we will give a summary of the main findings obtained in this thesis.