1993 Volume 19 Issue 6 Pages 1015-1022
Desulfulization reactivity of dolomite fully calcined in a temperature range of 9731473K was studied with thermogravimetric analysis (TGA) at 9731473K. The reactivities of calcined calcite, dolomite and magnesite were compared. The effect of the components of CaO and MgO in dolomite on the sulfurization of calcined dolomite was studied on the basis of the reactivities of calcined calcite and magnesite for sulfurization.
The reactivity of fully calcined dolomite for sulfurization was decreased with an increase in the calcination temperature and had a maximum sulfurization temperature of about 1373K. In the temperature range where both MgO and CaO could react with SO2 from a viewpoint of thermodynamical equilibrium, the component of MgO in dolomite as well as that of CaO reacted with SO2. Sulfur dioxide, however, might react selectively with the component of CaO in dolomite under chemical reaction control at the beginning of the reaction because CaO had a much higher reactivity for sulfurization than MgO. In the temperature range where CaO could only react with SO2 from thermodynamical equilibrium, the sulfation reaction of the component of CaO in dolomite almost attained 100% since SO2 could pass through intraparticle pores which were not plugged by the presence of unreacted MgO.
