In this study, we investigate desulfurization characteristics of granules m
ade of limestone powder. Their characteristics have been compared with thos
e of crushed limestone which is conventionally used as a desulfurization ag
ent. The granules have larger surface area than crushed limestone, and ther
efore, are expected to be highly efficient desulfurization agents. The resu
lts obtained from the experiments using thermogravimetry (TG) and a fluidiz
ed bed demonstrate that the granules are easily calcined (CaCO3 --> CaO + C
O2), and have a higher desulfurization rate than the crushed limestone. Fur
thermore, we calculated the reaction rate costant and activation energy in
the initial stage of desulfurization reactions, and the results also show t
hat the granules have a higher activity than crushed limestone. A fluidized
bed conducted under similar conditions shows that flying dust formation of
the granules is higher than that of the crushed limestone. It is suggested
that the granules are powdered in the initial stage of fluidization.