1. Improved Management of the SAGD Steam Chamber via Inflow Control Devices
Presented by Sudiptya Banerjee
SPE Heavy Oil/Horizontal Well Special Interest Group
Calgary, Alberta
March 28th, 2013

2. Uneven Production from a Horizontal Lateral
Sections of the lateral are favored for production due to the influence of:
Frictional pressure drop in the completion string
Variations in Kv and Kh along the wellbore
Variations in fluid composition and mobility
Non-uniform reservoir pressure along the lateral length

3. Flow Control Devices: The Application to SAGD
Injector Flow Equalization:
Even steam distribution/steam chamber growth
Higher sweep efficiency
Higher thermal efficiency
Potential for cheaper design (longer laterals, smaller ODs)
Producer Flow Equalization:
Supplements injection flow control
Smaller variation in steam trap control liquid height
Potential to choke back live steam entering the producer (autonomous flow controllers only)

4. Types of Flow Control Devices
Frictional Geometry
Big flow area, low velocity, viscosity sensitive
∆𝑃= 128𝜇𝐿𝑄 𝜋 𝑑 4 ∝ 𝜇𝑄
Restriction Geometry
Small flow area, high velocity, partially viscosity insensitive
∆𝑃= 𝜌 2 𝑄 𝐴 ∝𝜌 𝑄 2
Autonomous Geometry
Varies; big flow area, low velocity, viscosity insensitive
∆𝑃∝ 𝑎 2 𝑅𝑒 𝑏 𝑎 1 𝑅𝑒 𝑏 1 + 𝑎 2 𝑅𝑒 𝑏 𝑅𝑒 𝑡 𝑐 𝑑

5. Performance Characterization
Hybrid Geometry

6. Visualizing the Fluid Flow Path

7. Fluid Dynamics in the Device (Oil, 189 cP)

8. Fluid Dynamics in the Device (Water, 1 cP)

9. Case Study – SPE
The SPE paper submitted by John Stalder with Conoco Phillips, displays the superior performance of the Equalizer in an actual field installation. The geological description of wells 04, 05 and 06 are virtually identical. Wells 04 and 05 were conventional completions with slotted liners, well 06 with Equalizers. Well pairs were started in July Well pair 06, containing the Equalizer injector and producer was started April 2009, 21 months after wells Please note there was no toe tubing string in either the injector or producer after preheating ended. As you can see from the seismic data, well 06 performed exceeding well and the steam chamber developed rapidly, catching up as it were to the two similar well pairs.

10. Bitumen Production
As you can see, although well pair 06 was started 21 months after the two similar wells, it has an approximately 50% increase in production over the same amount of production time. Approximately 30 months into operation, well 06 was converted over to an ESP to handle the increased production.

11. Cumulative Steam-Oil-Ratio (CSOR)
The Cumulative SOR for well 06, also excelled in delivering a lower CSOR than the other wells demonstrating a superior thermal efficiency. The net value of lowering the CSOR by 0.1 or 0.2 equates to a different dollar value for each producer. I’m sure someone in this room could tell us what that would equate to for Cenovus.

12. Conclusion
Improved steam injection correlates to better thermal efficiency
Use of autonomous flow control devices in the producer provides additional confidence in steam trap control
Modeling critical to proper application
Questions?