Dynamic Simulation of Aquifer CO2 Disposal from Coal-Fired Power Plants in Alberta
CIM MineSpace 2001
Akihiro Hachiya, Kyla R. Makowecki, Raymond S. Suglo,
Green house gases have become a major concern within the international community over the last two decades due to their potential link to global warming. Carbon dioxide (CO2) is the principal greenhouse gas. In the Kyoto Agreement, Canada has committed to reduce emissions by 6 % below 1990 levels by 2012. This presents a serious economic challenge to Canada and Alberta. Over the next decade, oil sands production expansion, population and industry growth and energy demand will increase CO2 emissions. Current and future CO2 emissions and their economic implications in Alberta will be critical in formulating a comprehensive and balanced policy for dealing with concerns in this area. Disposal of carbon dioxide (CO2) in land aquifers is a potentially viable option for Alberta in dealing with long-term CO2 emissions. Studies have confirmed the existence of appropriate aquifers in the Alberta Basin for CO2 storage over a long geological period. Carbon dioxide is an ideal candidate for aquifer disposal because of its high density and solubility in water at relatively high pressures. In this study, the authors develop a computer simulation model of a scaled aquifer disposal system. The scaled model consists of an injector well, aquifer environment with dominant Ca++ and Mg++ cations. Liquefied CO2 is injected at an appropriate pressure and concentration through an injector well model. The injected CO2 migrates from the point of contact between the injector well and the aquifer domain to the main regime of the latter. The rate of migration is a function of porosity, permeability, cations, aquifer fluid flow regime and CO2 injected pressure. These models are validated using flue gas data from the 500 MW Wabamum Power Plant in Alberta. The design results show that the respective energy requirements for capturing, liquefying, transporting and injecting CO2 in the Glauconitic aquifer are 7,567 kW, 65.34 MW, 98.36 kW and 912.27 kW. The optimum number of transportation-injection systems is between 3 and 5. Reliability engineering analysis also shows that CO2 will be trapped safely in the aquifers by chemical and hydrodynamic trapping mechanisms partly as solids and as bicarbonates in water.
Greenhouse Gases, Coal-Fired Power Plants, CO2 Liquefaction, Liquid CO2 Trasportation, Liquid CO2 Injection, Reliability Engineering, Computer Simulation Modeling, Global warming, Oil Sands Production, Aquifer CO2 Sequestration