An Integrated Approach To Design Completions for Horizontal Wells for Unconventional Reservoirs

This paper presents a comprehensive and integrated workflow to design completions for a heavy-oil recovery process that involves injection and production through the same well. Unlike in traditional completion design, the transient effects are particularly important to consider while analyzing the long-term performance for these types of completions to capture the effect of variations or uncertainties in reservoir and fluid-flow characteristics over time. The proposed integrated workflow involves initial screening and selection of flow-restricting completions that can meet the desired injection and production performance based on a detailed wellbore hydraulics modeling tool. A select few completions are then analyzed for longer-term performance using a reservoir simulator that couples the flow-restricting nature of completions with flow in the reservoir. The use of best-in-art wellbore hydraulics model and reservoir simulator in a staged process yields an effective way to assess and optimize the completion design for these wells in a reduced time span. The workflow disclosed here can be used to design effective completions for a broad class of cyclic liquid-injection methods for heavy-oil resources.