The results of the world’s first field trial of the AICV in a Water and CO2 injection scheme was presented at the SPE ATCE in Dubai, September 2016 (SPE 181552), titled First Autonomous Inflow Control Valve (AICV) Well Completion Deployed in a Field under an EOR (Water & CO2 Injection) Scheme.
CO2 as Enhanced Oil Recovery (EOR) works most commonly by injecting CO2 into already developed oil fields where it mixes with and “releases” the oil from the formation, thereby freeing it to move to production wells. CO2-EOR projects resemble a closed-loop system where the CO2 is injected, produces oil, is stored in the formation or is recycled back into the injection well. One of the challenges is that breakthrough of free CO2 makes the process ineffective. The AICV® designed for CO2-EOR can shut off super-critical CO2 and water with CO2.
Experimental results from tests carried out with CO2, water, gas and different types of oil is encouraging. The oil companies using CO2 for EOR have pointed out the challenges with CO2 breakthrough and reproduction of large amounts of CO2 in heterogeneous and fractured reservoirs. For the purpose of storage of CO2 in the reservoir the AICV® has to close for both CO2 as gas/super-critical fluid and as CO2 solved in water. An AICV® design that is capable of closing for water will also close for less viscous fluids as CO2 gas/super-critical fluid.