Connotation, application and prospect of the fourth-generation separated layer water injection technology

The fourth-generation separated layer water injection technology was studied aiming at problems existing in current separated layer water-flooding technologies and production requirements. This paper discussed the connotation, core tool and key technologies, analyzed field application and prospected further development. The connotation is to realize digital real-time monitoring on single-well separated layer pressure and injection rate of injectors, network informationization of injection performance monitoring of blocks and reservoirs, and integrated reservoir and production engineering by combining injection program design and optimization with real-time adjustment of down hole separated layer water injection. An integrated water distributor, a core tool for this technology, and some key technologies including interval flow rate detection and injection allocation adjustment were developed. Moreover, this new technology was piloted in blocks and achieved expected results. In order to meet production requirements, it is necessary to keep research on key technologies, such as downhole interval flow rate detection, wellbore wireless communication, downhole self-power generation and vulnerable components fishing. In addition, this technology shall be properly combined with reservoir engineering, thereby developing a systematical and complete fourth-generation separated layer water injection technology that can underpin water flooding development sustainably.