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

Abstract

The integrity of Steam-Assisted Gravity Drainage (SAGD) wells are often threatened by the very steam that provides the process its name. High rate steam production, or the adiabatic flashing of steam condensate to a vapor state, often creates an environment of Љflashing erosionЉ, erosive damage created by the water-cutting effect of high velocity wet steam or the corrosive elements (e.g., carbonic acid) that can be associated with low temperature condensate. Condensate flashing to steam also carries additional risk from Љcavitation erosionЉ, erosion of completion equipment that occurs from the sudden shock wave impacts caused by the implosion of small liquid-free zones with the condensate, similar to the wellunderstood water hammer effect. Conventionally, to prevent the production of live steam or the flashing of steam condensate, operators have relied upon choking production rates based upon monitored temperature differences between injected and produced fluids. However, this methodology based on subcool carries its own risks and undermines the economic viability of SAGD projects. Another approach is to improve conformance of steam injection and fluid production by installing inflow/injection control devices (ICDs) in either, or both, the SAGD injector and producer. If properly designed, these devices in the producer can equalize heel-to-toe influx of bitumen emulsion, provide greater control of the sub-cool, and behave as an autonomous (or self-regulating) valve. This presentation will focus upon this last design objective. By coupling published performance equations for various ICD designs with steam behavior equations, competing designs will be evaluated for their likelihood of steam flashing within a SAGD completion and their respective ability to control flashed steam prior to the steam creating damage in the completion. Further, the discussion will examine possible future avenues of research, such as ICD designs with a steam throttle effect driven through a velocity-sensitive choking of steam production.

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

“…6 Expanded view of RCP insert in base pipe Movement of the RCP internal disk under oil and gas flow conditions (Halvorsen et al 2016) J Petrol Explor Prod Technol Fig. 7 View of a Hybrid ICD assembly with transparent housing subassembly (Banerjee et al 2013b) One of multiple pathways set in the circumference of a hybrid FCD subassembly (Banerjee and Hascakir 2015) Garcia et al 2009;Loretz and Hosatte 2007;Russell et al 2013a, b). Yet all FCDs may be sorted into three broad categories: channel-style FCDs, restriction-style FCDs, and autonomous FCDs (Al-Khelaiwi and Davies 2007;Banerjee et al 2013a;.…”

“…If the restrictionstyle FCD is oriented radially, the FCD also serves as the entrance into the production base pipe (Al-Khelaiwi and Davies 2007). The particular type of restriction may vary with common styles including thin and thick orifice chokes, nozzles, short tubes, and venturi restrictions (Abdelfattah et al 2012;Atkinson et al 2004;Banerjee et al 2013a, b;Banerjee and Hascakir 2015;Bybee 2008).…”

“…One immediate concern is FCD orientation; should the RCP not be installed in the well with gravity initially pulling the internal disk downward, the FCD will not function as designed. Another major concern is in the operational reliability of the disk itself; dependent on a moving part, the FCD fails should the disk ever jam, deform, break, or have its range of motion compromised by foreign materials (Banerjee and Hascakir 2015). In contrast, no other FCD geometry introduces the additional risk of a moving part.…”

“…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).…”

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

“…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.…”