| Greenhouse gas emissions and water usage are two major concerns in the power generation sector. Advanced clean coal technologies (i.e., solid sorbent CO2 capture technologies and combined wet/dry cooling system) are promising for future central power generation in order to achieve sustainable, secure, and efficient system performance. This dissertation describes research associated with advanced coal derived clean power generation, from near-term pulverized coal (PC) power plant strategies retrofitted for CO 2 capture, to long-term integrated gasification combined cycle (IGCC) power generation, to co-production IGCC with carbon capture and storage (CCS) co-fueled by coal and biomass.;In this study, the post-combustion solid sorbent based CO2 capture system for the PC power plant is optimized for integration in order to minimize plant modifications and the associated downtime. Due to significantly less steam usage in sorbent regeneration, the PC plant with advanced solid sorbent CO2 capture has better performance and lower cost of electricity than the plant using conventional amine scrubbing technology. By employing a combined wet/dry cooling system, the PC plant with CO2 capture reduces water usage significantly, while the performance and water usage are a function of ambient conditions as predicted by a mathematical model, the latter of which is validated by experimental data from the literature.;Pre-combustion solid sorbent based CO2 capture technologies used in the IGCC are evaluated by systems analysis and compared to Selexol TM CO2 capture. Compared with the SelexolTM approach, solid sorbent CO2 capture results in a power plant with significantly higher overall plant efficiency and more attractive economics.;Computational fluid dynamics (CFD) simulation models were developed for both solid sorbent CO2 capture alone, and combined water gas shift (WGS) and solid sorbent CO2 capture in the IGCC applications. ANSYS FLUENT and User Defined Functions (UDF) were the resources adopted to incorporate the fluid mechanics, heat and mass transfer, water vaporization, adsorption equilibrium and kinetics, and WGS reaction kinetics . The CFD models were validated by experimental data, and applied to commercial size fixed bed reactor designs and simulations. It was found that (1) the CO2 breakthrough time or CO2 loading capacity is independent of reactor geometry as long as the space velocity is constant, (2) the adsorption rate is the rate controlling step for CO2 capture using solid sorbent, and (3) break through occurs before the solid sorbent near the exit of the bed is fully utilized due to bulk transfer of the CO2 in the axial direction. However, a low space velocity can increase the loading of the sorbent. The CFD approach also assists in the design of effective thermal management strategies for the reactor in the case of combined WGS and solid sorbent CO 2 capture.;Co-feeding of biomass along with coal and the co-production of H 2 and synthetic fuels in IGCCs is evaluated for future clean coal power generation. It was determined by systems analyses that co-feeding and co-production IGCCs are preferable for renewable energy utilization and energy security, with the co-products being produced at competitive costs. |
