关键词: 竖罐炼锌, 黏土结合碳化硅, 氮化硅结合碳化硅, 热导率

Abstract: The problems,the measures and the results of Si₃N₄ bonded SiC bricks to replace fireclay bonded SiC bricks in a vertical zinc-smelting furnace of Dongling Zinc Industry Co.,Ltd.,were introduced,and the damage of two kinds of bricks after 20 months service was compared.The results show that:(1)compared with the fireclay bonded SiC bricks,the Si₃N₄ bonded SiC bricks present higher thermal conductivity,which can lower the temperature in the high temperature area by about 30 ℃;(2)the Si₃N₄ bonded SiC bricks show better corrosion resistance than fireclay bonded SiC bricks,the residual thickness of which in the high temperature area is 40-50 mm thicker than that of the fireclay bonded SiC bricks after 20 months of service;(3)during service,long cracks and leak-spot occurbecause the thermal stress of the Si₃N₄ bonded SiC bricks is not fully released,which can be relieved to a certain degree by adjusting the firing schedule during the removing of furnace accretion.If more efficient leak-spot repairing technology can be developed,the service life of Si₃N₄ bonded SiC bricks can be prolonged.

Key words: vertical zinc-smelting, fireclay bonded silicon carbide, silicon nitride bonded silicon carbide, thermal conductivity