Site Specific Geochemical Modeling of Groundwater and Co₂ Interactions: Implications for Geologic Carbon Sequestration

• Main Author: Johns, Elizabeth Kaylen
• Format: Text
• Language: unknown
• Published: BearWorks 2014
• Subjects: carbon sequestration; Lamotte Sandstone; Geochemist's Workbench; solubility trapping; mineral trapping; Geology; Hydrology; Water Resource Management; Thomas Hill; Ocean acidification
• Online Access: https://bearworks.missouristate.edu/theses/2171; https://bearworks.missouristate.edu/cgi/viewcontent.cgi?article=3172&context=theses

There are concerns that anthropogenic emissions of carbon dioxide into the atmosphere are contributing to climate change and ocean acidification. Currently scientists are using geochemical modeling of groundwater, rock and carbon dioxide interactions for geologic carbon sequestration purposes, as possible methods to mitigate the problem. Geologic carbon sequestration is a process of mitigation that has the potential to reduce the impact of carbon dioxide emissions into the atmosphere through the injection of carbon dioxide into a saline aquifer. This study investigated the extent to which carbon dioxide can be sequestered in the Lamotte Formation, a Cambrian aged saline aquifer, due to solubility and mineral trapping, at three well sites. A comparison of the geochemical suitability of the three sites in North-Central Missouri was also conducted. Site specific data such as temperature, carbon dioxide fugacity, pH, mineral content and groundwater composition were the input parameters needed to simulate the sequestration of carbon dioxide in a saline aquifer (Geochemist's Workbench software). The simulation results showed more aqueous CO2>could be sequestered at the Luecke Site for both the injection period (91.4 g/kg) and post-injection period (81.5 g/kg), while more solid phase CO2>could be sequestered at the Thomas Hill Site for the injection period (5.06 g/kg) and the first 500 years of the post-injection period (16.32 g/kg).