Chemistry and Process Design of Integrated Removal of Nitrogen and Sulfur oxides in Pressurized Flue Gas Systems
The work presented in this thesis evaluates the chemistry and process design of NOx and SOx removal during CO2-conditioning in oxy-fuel and chemical looping combustion systems. The primary goals of this thesis are to expand the current understanding of NOx and SOx chemistry and identify favorable conditions for achieving cost-effective control processes. Analysis of the reaction system by a detailed chemistry model, uncovers the importance of pH level in the liquid for the selectivity of the integrated NOx and SOx removal process. Moreover, a reduced mechanism is proposed for engineering calculations of the pressurized flue gas systems that captures the effect of pH and describes the relevant gas and liquid-phase chemistry. Process simulations, which utilize the reduced mechanism, enable evaluation of design of the integrated removal of NOx and SOx in pressurized flue gas systems. Technical evaluation of the integrated process reveals that removal rates of >98% for SO2 and >90% for NOx may be achieved. Moreover, the efficiency of the NOx removal can be improved by the presence of SOx and increased concentration of O2 in the flue gas. A comparison of the economic performance of the integrated removal process and the conventional emission control measures, i.e., selective catalytic reduction and wet flue gas desulfurization with limestone, shows significantly lower costs of removal by the integrated process.
Chalmers, Rymd-, geo- och miljövetenskap, Energiteknik
Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 0346-718X
Opponent: Professor Terry Wall, The University of Newcastle, Australia