29Si-NMR study of the absorbent for flue gas desulfurization

Publisher Summary This chapter discusses the structural changes of the absorbent during the hydrothermal reaction and sulfursulfursulfur dioxide (SO 2 ) absorption by Si-magic angle spinning nuclear magnetic resonance (MASNMR) using a model absorbent of calcium silicate hydrate to elucidate the mechanisms for a high utilization efficiency of calcium (Ca) component. The structure changes during the absorption of SO 2 enable Ca component present in a bulk to be exposed to the flue gas. The flue gas from a coal-fired boiler contains a high concentration of SO 2 that removes the emission from a chimney for the protection of environment from pollution. A wet desulfurization system is adopted for flue gas desulfurization (FGD) and exhibits a high utilization efficiency of Ca component in the absorbent but needs a large amount of water. The absorbent is extruded into granules, dried, and placed in the SO 2 absorber where SO 2 is removed from dirty flue gas to emit a clean flue gas.