Qualification of an Emerging Class of AICDs with Artificial Gravity: The Density-AICD Technology

Abstract

Abstract Conventional Autonomous Inflow Control Devices (AICDs) use the downhole viscosity contrast between wanted and unwanted fluids to preferentially produce one while restricting the other. Effectivity of these conventional AICDs is limited in light oil reservoirs where the difference in viscosity between oil and water is small or nonexistent. This paper describes an autonomous device that allows or impedes flow based on fluid density. It also presents the qualification testing program completed to advance the Density-AICD from a development concept to a commercially available product. The Density-AICD distinguishes between produced fluids at downhole conditions using an innovative buoyant float design with an effective density between oil and water. Production flow through the device generates an artificial gravity, amplifying the buoyant force used to control the Production Valve altering the tool's inflow rate. The fluid selector feature operates independent of Earth's gravity eliminating the need for downhole orientation in the completion. The performance of this novel tool has been demonstrated through computational numerical simulations, small scale sub-component testing, and a full-scale qualification test program. Sub-component and system level tests performed to evaluate fit for purpose and reliability included: Production Valve cycle and erosion testing, bearing erosion testing, National Association of Corrosion Engineers (NACE) component testing, pressure testing of a wash-pipe-free feature, system erosion testing, and flow performance for single and multi-phase flow. Density-AICD flow loop testing demonstrated substantial restriction to unwanted fluids based exclusively on density contrast. Test data showed a higher ratio of oil to water production than the initial design requirement and confirmed the ability of the device to toggle between open and closed positions depending on the surrounding fluid. A subsequent flow and function test was conducted after subjecting the tool to erosion testing with a negligible effect on performance and functionality. This paper will present the activities completed to qualify the Density-AICD technology and the benefit of the technology in very-light oil reservoir applications.