Project: Carbon Capture and Utilization within Ultramafic Mine Tailings Management
The goal of my research is reduce the costs and risks associated with the storage of ultramafic mine tailings while sequestering CO2 through carbon mineralization. Herein, the tailings are physically stabilized by the rapid formation of secondary magnesium carbonate minerals which act as a cement within the tailings. The magnesium is sourced from minerals found within the tailings, such as brucite and serpentine. Once released into water, the magnesium ions can react with dissolved CO2 to safely sequester the greenhouse gas in mineral form. Serpentine is typically far more abundant than brucite in ultramafic tailings, however brucite is highly more reactive with CO2.
This means that the selective targeting of brucite can bypass the need for energy intensive chemical processes, which currently hinder the economic viability of CO2 sequestration technologies. Furthermore, by exposing the tailings to a CO2-rich gas, such as the flue gases produced by on-site thermal power plants, the carbon mineralization reactions can be enhanced and accelerated, producing more rapidly and thoroughly cemented tailings. This research on tailings cementation through carbon mineralization could be instrumental to the mining industry by improving economics by reducing carbon taxes and also by stabilizing the tailings at a lower cost.