CO2 Capture and Sequestration: Practical Models for Leakage Risk Analysis & Water Challenges
Speaker: Ben Court, Graduate Student
Series: EEWR Brown Bag Seminars
Location: Engineering Quad E219
Date/Time: Friday, November 12, 2010, 12:00 p.m. - 1:00 p.m.
Most projected climate change mitigation strategies will require a very significant expansion of CO2Capture and Sequestration (CCS) in the next decades. Four major categories of challenges are being actively researched: CO2 capture cost, geological sequestration safety, legal and regulatory barriers, and public acceptance.
Firstly, CO2 sequestration leakage risk analysis almost always involves computational models that can vary in complexity and computational power necessary to run them. These models should all answer practical questions typically involving the spatial extent of the CO2 plume/pressure perturbations, and incorporating the spatial and temporal dynamics of CO2 trapping mechanisms and leakage. Development of models that can span the appropriate large spatial and temporal scales while including certain small-scale features like leakage pathways should be achieved by identifying the vital processes in the system and the scales at which they are important. Incorporating those scales into a systematic mathematical description of the system subsequently allows for practical model development.
Secondly, an additional major challenge category across all CCS operations was recently identified: water management. For example a coal-fired power plant retrofitted for CCS requires twice as much cooling water as the original plant. This increased demand may be accommodated by brine extraction and treatment, which would concurrently function as large-scale pressure management beneficial to the sequestration safety. At present the interactions among freshwater extraction, CO2 injection, pressure and brine management are being considered too narrowly-in the case of freshwater almost completely overlooked-in the technical and regulatory CCS community. Active management of CCS operations through an integrated approach can address challenges simultaneously with several synergistic advantages.