Cement-free iron trough castable for blast-furnace tapping and preparation method of cement-free iron trough castable

Abstract

The invention discloses a cement-free iron trough castable for blast-furnace tapping. The castable is prepared from special-grade bauxite, fused brown corundum, fused dense corundum, silicon carbide particles, silicon carbide powder, rho-aluminum oxide ultrafine powder, alpha-aluminum oxide ultrafine powder, silicon micropowder, spherical asphalt, a carbon source, metal silicon powder and an efficient water reducing agent. The preparation method includes: proportionally adding the raw materials into a stirring machine, performing dry mixing and stirring for 1-2min, adding water accounting for 4.5-5.5% of the amount of the raw materials, and stirring for 3-5min. Under the condition of freeness of cement addition, fused brown corundum is substituted by part of special-grade bauxite, and raw material cost is reduced while high iron influx is achieved; excellent normal-temperature and high-temperature performances are realized.

Description

technical field [0001] The invention belongs to the technical field of refractory materials, and in particular relates to a cementless iron ditch castable for blast furnace tapping. [0002] technical background [0003] At present, the iron trough castables used in domestic large and medium-sized blast furnace iron troughs generally use pure calcium aluminate cement-bonded Al 2 o 3 -SiC-C castable. However, the main damage mechanism of castables for blast furnace tapping trough is the oxidation of raw materials, the erosion of slag and iron, and the erosion of molten iron. One of the main materials for ironmaking slag is limestone, and its main component is CaO. Our conventional castables for iron trenches use pure calcium aluminate cement as a binder, which will inevitably increase the content of CaO in the castable, and the silicon micropowder introduced by the castable itself will make the CaO and SiO in the castable 2 The content of impurities has increased, and the s...

AI Technical Summary

Problems solved by technology

Our conventional castables for iron trenches use pure calcium aluminate cement as a binder, which will inevitably increase the content of CaO in the castable, and the silicon micropowder introduced by the castable itself will make the CaO and SiO in the castable 2 The content of impurities has increased, and the strength of castables has decreased significantly under high temperature conditions above 1450°C for a long time. The damage of castables has been accelerated under long-term immersion in molten iron.

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