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

Abstract

Summary 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.

Flow Control Devices in SAGD Completion Design: Enhanced Heavy Oil/Bitumen Recovery Through Improved Thermal Efficiencies

“…Since that initial field trial, FCDs/ICDs have been extensively used across the globe to delay water/gas breakthrough in high production rate horizontal wells (Abdelfattah et al 2012;Al-Khelaiwi and Davies 2007;Jain et al 2013;Karim et al 2010;Li et al 2013). Multiple differing FCD geometries have been commercialized to accomplish the goal of equalizing reservoir flux along the wellbore.…”

“…In this work, the focus is on the latter role as downhole throttling devices placed at the interface between well completion and reservoir to equalize a non-conforming production or injection fluid profile (Denney 2015;Li et al 2013). Used in this fashion, downhole FCDs are often referred to in industry as "inflow control devices" or "injection control devices" (ICDs), depending on the direction of reservoir flux (Banerjee and Hascakir 2015;Bybee 2008;Jain et al 2013;Li et al 2013). "Outflow control device" (OCD) is also often used in place of injection control device.…”

Management of Steam Flashing in SAGD Completion Design via the Implementation of Flow Control Devices

“…However, these descriptions are insufficient for SAGD operations, as they rely on an unreasonable assumption: incompressible fluid flow (Jain et al, 2013). In operations that frequent risk the production of live steam, methane, or even nitrogen during latelife blow down, performance descriptions that require incompressible fluids do not adequate address the needs of operators looking to simulate well behavior (Butler, 1994).…”

Design of flow control devices in steam-assisted gravity drainage (SAGD) completion

“…The larger family of devices accomplish this task in a multitude of roles, inclusive but not limited to subsurface safety valves (SSSVs), wellhead chokes, flow metering valves, valves downstream of the well within the process chain (surface safety valves), and downhole throttles on reservoir flux (Denney 2015;Li et al 2013). Used in this fashion, downhole FCDs are often referred to in industry as ''inflow control devices'' or ''injection control devices'' (ICDs), depending on the direction of reservoir flux (Banerjee and Hascakir 2015;Bybee 2008;Jain et al 2013).…”

“…Since that initial field trial, FCDs/ICDs have been extensively used across the globe to delay water/gas breakthrough in high production rate horizontal wells (Abdelfattah et al 2012;Al-Khelaiwi and Davies 2007;Jain et al 2013;Karim et al 2010;Li et al 2013). In late 2008, FCDs were proposed for the use in a steam-assisted gravity drainage (SAGD) well pair.…”