A REVIEW OF RESEARCH ON IMBIBITION MECHANISM OF UNCONVENTIONAL OIL AND GAS RESERVOIRS

Abstract

The process of spontaneously inhaling a certain wetting phase fluid in a porous medium is called imbibition. Reasonable utilization of the imbibition process can improve oil and gas recovery. This phenomenon has been widely used in fractured reservoirs. With the increasing development of unconventional oil and gas such as shale oil, the imbibition process of unconventional reservoirs has become a hot spot of current international research. This paper reviews the recent progress in the research on the imbibition characteristics of unconventional reservoirs, especially shale. This paper is mainly divided into three parts. The first part expounds the mechanism of imbibition and oil displacement in unconventional reservoirs and discusses the reasons for the low recovery rate of fracturing fluids. The second part reviews the research progress of imbibition test methods and points out the advantages and disadvantages of each method. The third section summarizes the influencing factors of the imbibition mechanism and measures the importance of each factor. This paper builds on existing research results and provides valuable and in-depth understanding for relevant researchers in this field.