Utilization of lime-silica solids for flue gas desulfurization

Enhancement in the utilization of lime-silica solids for flue gas desulfuri zation has been experimentally investigated on the basis of their physical and chemical properties. Along the pozzolanic reaction, the utilization of Ca(OH)(2) in the solids increased because of the increase in their BET spec ific surface area resulting from formation of a calcium silicate phase. Con tinued hydration of the excess SiO2 after the reaction had been completed, however, reduced the utilization of the sorbent particles because of undesi rable precipitation of Si on the silicate. Increases in the initial SiO2/Ca (OH)(2) ratio and the reaction temperature drastically reduced the period o f preparation for solids having the same utilization and increased the maxi mum utilization. It is proposed that the changes in morphology and effectiv e distribution of Si and Ca in the silicate phase were responsible for the latter utilization enhancement.