(1) The CaO content is high and the SiO2 content is low. Because the combination of SiO2 and CaO reduces the effective CaO content of lime.

(2) The sulfur content is low, and the sulfur content is too high, which affects the desulfurization ability of lime and even increases sulfur.

(3) The firing rate is small and the firing rate is large, indicating that a large amount of CaCO3 in the lime does not become CaO. After the furnace is added, CaCO3 decomposes and absorbs heat, which affects the thermal efficiency of the furnace and makes the slagging and temperature control difficult. 

(4) The degree of entry into the furnace should be moderate.