Integrating Enhanced Oil Recovery and Carbon Capture and Storage Projects: A Case Study at Farnsworth Field, Texas

Abstract

Abstract The Southwest Partnership on Carbon Sequestration (SWP) is one of seven large-scale demonstration projects sponsored by the U.S. Department of Energy. The SWP has a goal of permanently sequestering more than 1,000,000 metric tonnes of CO2 in an active EOR project in a mature waterflood in the Anadarko basin. The CO2 for this project is anthropogenically sourced from a fertilizer and an ethanol plant. As of the end of 2015 the field has 13 CO2 injectors and has sequestered 386,695 metric tonnes of CO2 between October 2013 and July of 2015. Goals of the project include optimizing the EOR/storage balance, ensuring storage permanence, and developing best practices for carbon storage utilizing man-made CO2. The field site provides an excellent laboratory for testing a range of monitoring technologies in an operating CO2 flood since field development is sequential and allows for multiple opportunities to record zero CO2 baseline data, midflood data, and data from fully flooded patterns. The project has acquired data at a number of scales including a 42 mi2 3D seismic survey, baseline and repeat 3D VSP surveys centered on three injection wells, cross-well tomography baseline and repeat surveys between injector/producer pairs, a borehole passive seismic array to monitor for induced seismicity, a distributed temperature system, and bottomhole pressure and temperature sensors. The project has drilled three wells in the field, and has acquired over 750 ft of core in the Morrow B reservoir interval and associated caprock units. Additional monitoring focuses on CO2 soil flux, groundwater chemistry, reservoir fluids chemistry, and aqueous and gas-phase tracer studies. All acquired data have contributed to detailed geologic models used for fluid flow and risk assessment simulations. 3D VSP and cross-well data with repeat surveys have allowed for direct comparisons of the reservoir prior to CO2 injection and at eight months into injection, with a goal of imaging the CO2 as it moves away from injection wells. Additional repeat surveys at regular intervals will continue to refine direct CO2 imaging as production and injection data are integrated with newly acquired and interpreted data. All models are regularly updated. In this paper the project goals will be outlined, progress towards goals enumerated, and current geologic and simulation models will be introduced. In addition, initial results from time-lapse monitoring of movement of CO2 in the reservoir will be discussed.