PROCEDURE FOR NOTCH CLOSURE IN BLAST FURNACE Russian patent published in 2011 - IPC C21D7/00 

FIELD: metallurgy.

SUBSTANCE: procedure for closure of notch in blast furnace consists in metering components and in preparation of thick notch mass in mixer, in loading thick notch mass into machine for closure and its extrusion through tip of machine into notch channel. Also, in the mixer there is prepared water-free notch mass of humidity not over 2.2% of the following composition, wt %: chamotte powder of fraction not over 3 mm - 5.3-5.8; refractory milled clay of fraction not over 0.3 mm - 27.8-28.4; milled coke of fraction not over 3 mm 17.3-18.0; carbon containing concentrate 16.2-17.3; crystal silicon carbide 11-11.6; coal-tar asphalt 2.3-2.5; coal-tar resin - the rest. As carbon containing concentrate there is used spent graphite electrodes of electric arc furnaces with contents of carbon 80-98 % of fraction not over 3 mm, while coke of fraction not over 3 mm is used with content of carbon at amount of 60-90 and iron oxide not over 0.3 wt %.

EFFECT: increased operational properties of notch of blast furnace; raised strength and plasticity of refractory mass at low prime cost and at ecological safety.