Concerns for rising levels of CO₂ in the atmosphere have lead to a myriad of schemes to reduce emissions. Many of these are complicated, expensive, and untried. Coal-fired electrical generation accounts for about 49 percent of U.S. electricity generation. Shifting generation capacity away from coal is the goal of many, yet as this statistic shows, the U.S. has a heavy dependency on coal-fired base-load generation. What is needed is a way to retrofit existing coal fired power plants to mitigate at least some of the giga-tonnes of CO₂ released annually.

Carbon Capture and Storage in association with greenhouse gases are a major concern in the world today.

This thesis is an outgrowth of a research partnership between the University of Wyoming and the Jim Bridger Power Plant (Rocky Mountain Power) to develop a process for capture and mineralization of flue gas carbon dioxide (CO ₂) using an accelerated mineral carbonization process with fly ash particles as the absorbent. This process may have several advantages over other approaches because it is an environmentally acceptable, single step process occurring at near ambient pressures and temperatures that can compliment conventional CCS processes. In addition the use of fly ash particles as an absorbent avoids the costs of processing or engineering an absorbent. The purpose of this thesis is to evaluate the capture costs and economic feasibility of the mineralization process.

Two models were used to estimate the capture costs and economic feasibility of the Jim Bridger Power Plant CO₂ Mineralization Project (JBP). The first was a cost of capture model which was used to estimate CO₂ capture costs and how changes in the CO₂ to ash capture ratio and quantities of CO₂ captured affect capture costs. The second was a financial feasibility model which considered the time value of money. This second model considered the net present value (NPV) and internal rate of return (IRR) for the process using different pricing scenarios and processing parameters. The analysis was based on a full size reactor system capable of capturing 90 percent of the CO₂ emitted by Unit 2 of the Jim Bridger Power Plant. Unit 2 is a 530 megawatt pulverized coal-fired generator which emits 4.9 million tones of CO₂ annually. The cost estimates for the full size reactor system were developed by scaling up from a pilot project currently being conducted at the plant.

The results show estimates that range from $7.37 to $27.30 per metric tonne of CO₂ captured. This range compares favorably with other estimates in the literature. Furthermore, since this system could be retrofitted to an existing power plant, added costs would be considerably less per installed kilowatt-hour. Our preliminary estimates place this cost at $94 per installed kilowatt hour.

This thesis will introduce the process, give an update on the project and present our preliminary findings.