The promise and problems of enhanced oil recovery methods

Enhanced oil recovery (EOR) methods are outlined in a systematic and balanced manner, and the current impact of these methods is assessed in light of field experience. The main EOR methods are described briefly, their current status is described, and the reasons for the lack of success are examined. The paper doe on voluminous statistics, nor does it give another set of screening criteria. Rather it develops the process discussion in terms of mobility ratio and capillary number. Successful EOR-methods such as SAGD are modifications of standard methods to unusual reservoir conditions. Certain EOR methods, such as chemical floods, have inherent limitations, explaining the lack of success in the field in contrast to laboratory.