Abstract:
Natural zeolite was utilized as an agent to increase the reactivity of lime for desulfurization. Due to the presence of
hydrous silica aluminates in zeolite, a pozzolanic reaction ensued which ended up with an increase in the surface area of lime thus
making it more reactive. Tests were done in a pH-stat apparatus and a fixed bed reactor, representing wet and dry flue gas
desulfurization (FGD), respectively, to check if lime reactivity was augmented by the addition of zeolite. It was found that zeolite
amplifies reactivity of lime with the highest reactivity being achieved with a lime to zeolite ratio of 1:1 (by mass). This was confirmed
by Brunauer Emmett Teller (BET) surface area analysis (surface area increment with the reactivity) and scanning electron
microscopy (SEM) imaging (rough morphology being formed). Further optimization tests were conducted in the pH-stat apparatus
with the aid of design expert software to quantify linear, quadratic, and interactive effects of four variables (temperature, lime to
zeolite ratio, liquid to solid ratio, and stirring speed). Temperature as a variable had the highest effect, followed by lime to zeolite
ratio. Stirring speed had the least effect on the reactivity