A novel, cost-saving approach combining advanced electronic and chemical technologies for rapidly acquired reservoir flow measurements and early-alteration of flows is described. The combined technologies improve CO2 injection, leak detection, and reservoir flow management in offshore CO2 enhanced oil recovery (EOR) and carbon capture and storage (CCS) projects. The approach is based on old and new technologies that have been field-proven in land-based operations. It employs reservoir flow-induced micro-deformation measurements by tiltmeters and absolute seafloor position monitoring using global positioning systems combined with underwater acoustic distance measurements from the sea surface to instruments installed in the seafloor over offshore reservoirs.

These systems can acquire micro-deformation data, which allows for geomechanical inversion analysis to provide 3-D reservoir flow images. Real-time temperature, pressure, and other data from fiber-optic sensors may also be needed to better characterize some CO2 flows. New flow-controlling and leak-sealing chemical systems and placement methods combined with conventional ones have improved the options for management of flow paths both inside and outside of offshore reservoirs.

The paper includes a discussion on how the monitoring technology has evolved from similar methods proven in EOR projects, and more recently in CCS projects, to identify reservoir flows and pinpoint abnormal ones. An example of normal CO2 flow results is presented to show how operators can calibrate flow-prediction software models and make fast decisions to apply flow enhancing methods that improve CO2 sweep efficiency, increase oil production, and better utilize reservoirs' CO2 storage capacity. Another example shows the early identification of an abnormal-flow path location that enables operators to make timely selections of sealing methods and materials to eliminate unwanted flows inside or outside of reservoirs and ensure planned CO2 plume movement and containment within reservoirs.

The CO2 flow controlling and remediation technology's history of field proven success is described along with the recently developed versions. Generic case histories of conventional methods on land vs. the proposed offshore systems are compared to show how the new approach creates synergy that can improve the performance of offshore CO2 EOR and CCS projects while reducing operating costs.

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