ConocoPhillips operates Surmont, which is the first Steam-Assisted Gravity Drainage (SAGD) project to implement Flow Control Devices (FCDs) in producer wells. This study was conducted to evaluate the production performance of different liner completion strategies. The analysis compared well pairs completed with slotted liners (SL) to producers completed with FCDs, both liner deployed (LD-FCD) and tubing deployed (TD-FCD), and investigated the impact of FCDs in injectors. An extensive analysis was conducted using available production and temperature data along the wells. The wells were completed using various fixed-resistance FCD settings, while some wells were completed using variable setting designs. As time went on, several of the slotted liner producer wells were retrofitted with tubing-deployed FCD completions. One of the key objectives of the study was to determine the success rate of tubing-deployed FCDs and their performance relative to liner-deployed FCD wells. Another objective was to evaluate the impact of retrofitting slotted liner SAGD injectors with tubing-deployed FCD completions. In this study, a grading system was established based on the reservoir quality along the well for both injector and producer. For similar graded well pairs, LD-FCDs had better production performance than TD-FCDs. Considering similar graded reservoir quality, FCDs consistently performed better than slotted liners, in both conformance and production acceleration. The production analysis showed that the FCD flow restriction was a major controller of the conformance, but considering the self-choking phenomenon of the reservoir, most FCDs can perform positively in different circumstances. In this study, the self-choking effect of the liquid pool is discussed and explained for different reservoirs and variable subcool. Generally, if erosion is not a factor, FCDs can create a more controlling system than liquid-pool dominant systems. In these cases, both conformance and production acceleration is enhanced if operators yield lower subcools and greater draw-down pressures.

Summary With steam-assisted-gravity-drainage (SAGD) operations, there will be times that the producer downhole temperature falls below the desired level. This situation may occur when a shut-in is required because of facility or well operational issues. Cooling bitumen and steam condensate, which continue to drain and raise the liquid level over the producer, cause difficulties with the restart. The producer could also cool if the well pair is converted prematurely from circulation to full SAGD mode. A variety of artificial-lift technologies have been applied in field applications. However, with its dual-tubing-completion design and gas lift system, Devon has successfully used partial SAGD methods to optimize restart strategies and effectively deal with times when the producer unexpectedly cools. This paper describes three SAGD operating modes used by Devon at Jackfish: full SAGD, semi-SAGD, and partial SAGD. During partial SAGD, the fluid return from the injector stops while steam injection continues down either the long tubing (LT), short tubing (ST), or the annulus. The producer continues to be circulated with the appropriate steam-injection rate into the LT and fluid returns up the ST. Numerical-simulation results associated with partial SAGD are presented. Partial-SAGD applications at the Jackfish SAGD project are discussed.

For ConocoPhillips, technology is a key driver and development accelerator to continuously improve its SAGD operations. The deployment of conventional Flow Control Device (FCD) technology in Surmont has allowed ConocoPhillips to realize shorter circulation times and higher oil production rates. These benefits have been realized while ensuring liner and well integrity. Optimizing the well start-up process in SAGD has been a challenge at Surmont and in the industry in general. SAGD well start-up involves heating bitumen through a mostly conductive process to allow the SAGD mechanism to initiate. A recent breakthrough in the circulation strategy for wells equipped with FCDs at Surmont was developed and implemented by the ConocoPhillips Technology and Operation teams. This new approach has been possible by integrating FCD characterization and erosion testing with complex engineering principles such as convective heating, sand control, reservoir multiphase flow and wellbore flow dynamics. ConocoPhillips commenced the implementation of the new strategy in the field between 2015 and 2016 with great success. Benefits of this circulation strategy by fully utilizing the FCD technology are numerous, including a reduction of circulation duration, substantial increase in early time oil and liquid production and accelerated well ramp-up. The paper begins by presenting the concept of this new circulation strategy. Then, details on various SAGD mechanisms and associated FCD physics are explained. Finally, field data is presented to illustrate the successful implementation of this strategy along with an analysis of the operating results.

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Steam-Assisted Gravity Drainage (SAGD) is a complex process that often requires more control relative to conventional applications during production operations. Flow Control Devices (FCDs) have been identified as one of the technologies that offer improved downhole steam utilization and injection/production efficiency. The first FCD completions, with a helical geometry, were installed in SAGD wells at the ConocoPhillips Surmont project over a decade ago. The installations have shown improved steam chamber conformance and reduced steam-oil ratio (SOR) while accelerating bitumen production. Since then, various FCD geometries have been investigated and used, with several of them explicitly designed with a steam blocking capability. This study used a numerical simulator to investigate the performance of these various FCD geometries. This comprehensive study started testing several geometries in a flow loop and using the data obtained to develop a mechanistic model to characterize the flow performance of the FCDs and finally evaluating their performance in a holistic manner via a numerical simulator. By using mechanistic modeling, it was ensured that the performance of the devices was accurately represented, and the physics of the process were considered. The analysis used a commercially available numerical simulator to evaluate the performance of the various FCD geometries in SAGD operation. Three sector models representing different reservoir qualities observed in Surmont were used for the analysis. Additionally, various operating strategies were investigated for each sector model to ensure that a comprehensive understanding of each FCD geometry was achieved. The results of this study showed that FCD flow resistance setting or nozzle size played a significant role in the production performance of the wells in liner deployed FCD applications. Additionally, the steam blocking geometries resulted in increased cumulative production and lower SOR relative to other geometries. The FCD geometry did also impact the development of the steam chamber. Nevertheless, if the FCD completions are configured with the proper flow resistance setting or nozzle size, they provide a proactive measure, which leads to significantly better performance compared to a non-FCD completion. With lower subcool, the geometry of the FCD has a greater impact on the performance of the well. It was also confirmed that an aggressive operating strategy results in better performance of the FCD completions.