The world needs reliable energy. As an industry, we supply that energy. Moreover, our product is one of the major contributors to increasing atmospheric CO2. Steam assisted Gravity Drainage (SAGD) technique alone contributes nearly 1.4 million barrels per day of oil production but with a range of steam oil ratios, the effectiveness of this production method is often challenged and seen as having high associated GHG emissions per barrel.

We cannot solve this dilemma, but by better understanding the sciences of the reservoir and implementing new technologies at the primary level of production, we can help to be part of the solution. One production enhancement technique, injecting NCG at the late life SAGD wind down process is an effective but challenging operation due to high mobility of the gas and subsequent breakthrough at the production well. A new design of Autonomous inflow control valve's (AICV) can distinguish the difference in viscosity of the fluid, and therefore they can strongly choke and shut the NCG effluents zones as breakthrough occurs in the SAGD production well.

The AICV design is truly autonomous based on Hagen-Poiseuille equation and Bernoulli's principle. The AICV is utilizing the difference in flow behavior in a laminar flow restrictor and a turbulent flow restrictor to differentiate fluids based on the difference in pressure drop between oil, water, emulsions, gas, CO2 and steam. This will allow the AICV to choke and/or shut off unwanted water, gas, CO2 and steam coming into the producer well. To understand the AICV behavior for a NCG breakthrough application, a laboratory experiment which illustrate the performance of AICV technology and reference orifice type ICD technology have been conducted.

Laboratory experiment results illustrate the performance difference between AICV technology and reference orifice type ICD technology illustrate a significant, of more than 80% reduction, in NCG choking performance, when compared to the ICD type nozzle. The laboratory test performance results are used in reservoir simulations. Reservoir simulation results show that utilizing AICV in late life SAGD production well can significantly reduce NCG production and improve the recovery of SAGD operation by retaining more of the injected gas within the reservoir.

In today's engineer's toolbox, a variety of new technologies exist that can help achieve the targets for late life SAGD. The new editions to Flow Control Device (FCD), Autonomous Inflow Control Valve (AICV), has evolved to the point that operators can operate in late life in a way that could demonstrate clear economic efficiencies with a reduced environmental impact. Reducing NCG breakthrough, greatly improves the economics and reduce greenhouse gas emissions for each barrel of oil produced thus reducing the carbon footprint and the impact to late life SAGD operation.

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