ABSTRACT
The process for using surfactants to affect the recovery of crude petroleum oil from underground porous oil fields is far from being realized. This chapter illustrates the difficulties in recovering the oil and discusses how, with systems such as microemulsions, some of these difficulties may be overcome. It focuses on the use of surfactants to attain ultralow interfacial tensions and improve oil recovery and discusses the microemulsion flood. The delivery of these surfactants has been proposed in various forms, low concentration micellar solutions, high concentration solutions, foams, and even vesicles, and in the form of microemulsions. The oil-in-water microemulsion has a very low surface tension against excess oil and similarly water-in-oil microemulsion has a low surface tension against excess water. The two problems facing the last stage of recovery are the stability of the displacement and capillarity. The chapter describes the fluid flow and addresses the problems of stability and the problem of capillarity.
