A comprehensive review of polymer and alkaline/surfactant/polymer flooding applied and researched in Kazakhstan

Abstract

Polymer flooding and alkaline/surfactant/polymer flooding have been applied throughout the world for more than 30 years. However, they were not as popular as other types of enhanced oil recovery methods such as thermal methods and gas injection in Kazakhstan. To date, the polymer and alkaline/surfactant/polymer (ASP) flooding processes have been applied successfully in several Kazakhstan oil fields due to technology progress and changes in chemical costs and successful polymer and ASP flooding experiences in the world. This paper shows application of chemical enhanced oil recovery methods in several oil fields in Kazakhstan, where pilot on-site experiments and core flood tests on chemical flooding methods were carried out. The paper describes the latest pilot tests on polymer flooding in oil fields such as Nuraly, Zaburunie and Kalamkas, where polymer flooding alone contributed approximately 150 000 tons of produced crude oil. Several ASP floods also have been tested in local fields. Laboratory researches were carried out in core samples of Eastern Moldabek and Karazhanbas oil fields. Increase in oil recovery up to 80 % have been reported, however pilot tests have not been implemented yet. This paper discusses researches conducted in these fields including field / laboratory results, methods of flooding, polymer types and concentrations used.