A new and fast waterflooding optimization workflow based on INSIM-Derived injection efficiency with a field application

Abstract Traditionally, production optimization is performed based on repeatedly running a forward reservoir simulation model, which is quite time-consuming. Recently, we developed a computationally efficient data-driven model, which is referred to as interwell-numerical-simulation model (INSIM), for history matching, characterizing interwell connectivity, monitoring, and optimization for a waterflood. In this research, we develop a new workflow for fast optimizing waterflooding performance which only requires one single INSIM forward run. Specifically, the well injection rate and production rate are determined by the INSIM injection efficiency proposed in this work and the existing injector-centered allocation factors. Like streamline simulation, the basic idea of the optimization workflow is to try to recover more oil from those injector-producer pairs that have more remaining oil left by injecting more water to those connections; while for those connections without much oil left, we simply decrease the water injection to prevent more water being injected wastefully without bringing more oil. The criterion to tune the injection rate is based on the proposed injection efficiency for water injection, which is a quantity represents the relative business value for water injection for an injector. The larger the injection efficiency is, the more oil can be produced by injecting a unit amount of water. The advantage of this method is that the well controls are optimized based on the reservoir-engineering point of view which is easy to be accepted by operators. Also, the new workflow is very easy to implement and much more computationally efficient than the traditional optimization workflow. We test the proposed workflow with two examples including a large-scale field example. The computational results indicate that, by using the proposed workflow in INSIM, the field oil production is boosted with less water being produced.