Characteristic analysis of ring-forming material in rotary kiln
The phenomenon of ring-formation in rotary kilns is a crucial factor that impedes the development of oxi-dized pellets produced by rotary kiln.The chemical composition,microstructure,mineral phase composition and ele-ment distribution of oxidized pellets and ring-forming material in rotary kiln were analyzed by XRD and SEM-EDS to elucidate the formation mechanism of ring-forming material.The findings indicate that the primary ring-forming ma-terial is hematite,followed by quartz,calcium ferric olivine,calcium magnesium olivine,feldspar,and other silico a-luminate compounds.The powder generated by the pellets and coal ash forms low-melting-point compounds that liq-uefy at high temperatures and infiltrate into the pellets.The hematite in the liquid phase then re-crystallizes and ad-heres to the pellet surface,resulting in the formation of stable ring-forming material.By improving the ore blending structure to reduce the content of silicon and alkali metals,optimizing the quality of fuel resources to reduce the in-take of low-melting-point substances,and improving the operating conditions of each process to reduce the intake of powder,the ring-forming phenomenon can be effectively inhibited.
NETL
NSTL
万方数据
