Controlling steam conformance in the horizontal injectors of SAGD projects is widely accepted as being critical for commercial success. This work is focused on steam distribution in horizontal injectors in mobile, heavy oil (non-bitumen), thermal development projects. Steam Conformance can be achieved by tubing or liner deployed FCD's (flow control devices). Liner deployed FCD's have several advantages over tubing-deployed FCD's which includes: smaller tubulars, lower capital costs, reduced well interventions, and potentially reduced surveillance requirements. This paper provides an overview of a collaborative development methodology for liner-deployed FCD's in horizontal steam service between a service company and operator. This methodology included: Establishing functional, operational and dimensional basis of designComputational fluid dynamics (CFD) analysis of the FCD design and phase-split testing in the Horizontal Steam Injection Test Facility (HSITF)Design revisions based on CFD, HSITF and shift testing resultsField installations results based upon fiber optic, thermo-hydraulic, and mechanical analysis These FCD's were designed with sliding-sleeve technology to enable opening or closing of each device. Different specifications of electroless nickel (EN) coatings were also tested to determine the performance for scaling and corrosion resistance. Within 6 months, three versions of the FCD's were tested in the HSITF with accompanying CFD. For each version the shifting forces before and after ~6 weeks of steam injection were measured. Each generation was improved based on the data from the prior version. In December 2018, three FCD's were installed in a large bore horizontal steam injector in a tubing deployed completion for field qualification of the devices. This installation was the first step of a one-year field qualification test. The full test will involve multiple interventions to opening and closing the FCD's. A capillary tubing with fiber optic wrapped around the tubing and devices can confirm FCD openings or closings. The field qualification will also test the local operational capability to shift the FCD's. At the end of the field qualification, the flow devices will be retrieved for inspection and identification of further design improvements.

Steam conformance control in horizontal injectors is important for efficient reservoir heat management in heavy oil fields. Suboptimal conformance and non-uniform heating of the reservoir can substantially impact the economics of the field development, oil production response and result in non-uniform steam breakthrough. In order to achieve the required control, it is essential to have an appropriate well completion architecture and robust surveillance. Five fiber optic systems, each utilizing a unique steam conformance control completion configuration, have been installed in two horizontal steam injectors to help mature steam injection flow profiling and conformance control solutions. These fiber optic systems have utilized custom designed fiber optic bundles of multimode and single mode fibers, for distributed temperature sensing (DTS) and distributed acoustic sensing (DAS) respectively. Fiber optic systems were also installed in a steam injection test flow loop. All the optical fibers successfully acquired data in the wells and flow loop, measuring temperature and acoustic energy. A portfolio of algorithms and signal processing techniques were developed to interpret the DTS and DAS data for quantitative steam injection flow profiling. The heavily instrumented flow loop environment was utilized to characterize DTS and DAS response in a design of experiment matrix to improve the flow profiling algorithms. These algorithms are based on independent physical principles derived from multiphase flow, thermal hydraulic models, acoustic effects, large data array processing, and combinations of the foregoing methods for both transient and steady state steam flow. A high-confidence flow profile is computed based upon convergence of the algorithms. The flow profiling algorithm results were further validated utilizing a dozen short-offset, injector observation wells in the reservoir that confirmed steam movement near the injectors.

Summary Steam-conformance control in horizontal injectors is important for efficient reservoir-heat management in heavy-oil fields. Suboptimal conformance and nonuniform heating of the reservoir can substantially affect the economics of the field development and oil-production response and result in nonuniform steam breakthrough. To achieve the required control, it is essential to have an appropriate well-completion architecture and robust surveillance. Five fiber-optic systems, each with a unique steam-conformance-control-completion configuration, have been installed in two horizontal steam injectors to help mature steam-injection-flow profiling and conformance-control solutions. These fiber-optic systems have used custom-designed fiber-optic bundles of multimode and single-mode fibers for distributed-temperature sensing (DTS) and distributed-acoustic sensing (DAS), respectively. Fiber-optic systems were also installed in a steam-injection-test-flow loop. All the optical fibers successfully acquired data in the wells and flow loop, measuring temperature and acoustic energy. A portfolio of algorithms and signal-processing techniques was developed to interpret the DTS and DAS data for quantitative steam-injection-flow profiling. The heavily instrumented flow-loop environment was used to characterize DTS and DAS response in a design-of-experiment (DOE) matrix to improve the flow-profiling algorithms. These algorithms are dependent on independent physical principles derived from multiphase flow, thermal hydraulic models, acoustic effects, large-data-array processing, and combinations of these methods for both transient and steady-state steam flow. A high-confidence flow profile is computed using the convergence of the algorithms. The flow-profiling-algorithm results were further validated using 11 short-offset injector observation wells wells in the reservoir that confirmed steam movement near the injectors.

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Steam injection profile control is a significant challenge for thermal recovery of heavy oil with horizontal wells. There is no reliable commercially available method for controlling two-phase steam distribution in horizontal laterals. In fact, there is not even a commercial laboratory capable of testing such devices. To address this gap, Chevron constructed a surface horizontal steam injection test facility in the Kern River Field located outside of Bakersfield, California. This facility is used for testing commercial and proprietary devices for improving control of steam distribution along a lateral in a horizontal well. The horizontal steam injection test facility tests the capabilities of a wide range of full-sized downhole completion equipment (tubing and liner flow control devices, tubing/liner and annulus/liner isolation devices) at the surface under precise controlled conditions. This paper discusses the need for horizontal steam injection wells, steam distribution control, and the current "state-of-the-art" horizontal steam injection completions or, more accurately, the lack of steam profile controls currently available. Also discussed are the three areas critical for controlling the steam profile along a lateral: 1) liner-open hole, 2) liner, and 3) tubing-liner. The capabilities of the test facility, impact of flow regimes, initial test results, and a possible pathway to field deployment of promising technology are also addressed.