A kind of iron trench castable combined with ammonium ion stabilized silica sol

Abstract

The invention discloses an ammonium ion-stabilized silica sol-bonded castable for iron trenches. The composition in mass percentage is as follows: brown corundum 55-70%; silicon carbide 15-30%; ball pitch 1-3%; composite silicide graphite 0.5-3%; alumina micropowder 5-10%; antioxidant 1-5%; wherein, 5-7wt% of ammonium ion-stabilized silica sol is added. The invention adopts ammonium ion-stabilized silica sol binder to minimize the introduction of harmful impurities such as alkaline oxides, and the prepared castable has a dense structure, good construction fluidity, rapid demoulding, rapid baking, and oxidation resistance on site. Good, high strength at room temperature and medium and high temperature, good effect of material on-site use, effectively increasing the amount of iron passing through the iron channel at one time. By introducing the carbon raw material in the form of chemically coating the surface of the carbon raw material with antioxidants, the carbon can be minimized to be oxidized and lost during baking and other links, and fully play the role of anti-slag iron corrosion.

Description

technical field [0001] The invention belongs to the technical field of refractory materials, and in particular relates to an iron trench castable combined with ammonium ion-stabilized silica sol. Background technique [0002] In the prior art, the iron trench of the blast furnace casting field is mainly constructed with cement-bonded aluminum-silicon-carbide-carbon castables. The cement brings calcium oxide, and low-melt phases such as feldspar in the material reduce the corrosion resistance of the castable and deteriorate the material properties. In addition, the castable needs to be baked to remove moisture after construction, and the cement combined castable has strict requirements on the baking temperature curve. After the cement is hydrated, several hydrate phases containing crystal water are formed, and the dehydration temperature range is narrow. Poor temperature control can easily cause the castable to burst. Some manufacturers use sodium hydroxide-stabilized silic...

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Problems solved by technology

The cement brings in calcium oxide, and the low melting phase such as calcium aluminum feldspar in the material reduces the corrosion resistance of the castable and deteriorates the material performance

In addition, castables need to be baked to remove moisture after construction, while cement-bonded castables have strict requirements on the baking temperature curve. After cement hydration, several hydrate phases containing crystal water are formed, and the dehydration temperature range is narrow. Poor temperature control can easily cause the castable to burst

Some manufacturers use sodium hydroxide-stabilized silica sol as a binder to prepare iron trench castables. This silica sol is generally prepared from water glass as a raw material, which will bring in more low-melting substances such as sodium ions, and is slightly more alkaline. , react with metal silicon and metal aluminum at room temperature, resulting in serious carbon oxidation of castables under medium temperature and high temperature conditions, thicker oxide layer, increased pores after oxidation, reduced strength, deterioration of slag iron erosion resistance and erosion

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