Silica brick for glass furnace

Abstract

The invention discloses a silica brick for a glass furnace, and belongs to the technical field of refractory materials. The silica brick for a glass furnace comprises: by weight, 30 to 45% of silica having particle sizes of 3 to 1.0mm, 5 to 25% of silica having particle sizes of 1.0 to 0.5mm, 30 to 50% of silica having particle sizes less than 0.5mm, an additive and a composite additive, wherein the weight of the additive is 5 to 15% of the total weight of the silica and the weight of the composite additive is 2 to 10% of the total weight of the silica. SiO2 content of the silica is great than or equal to 99%. Al2O3 content of the silica is less than or equal to 0.25%. Fe2O3 content of the silica is less than or equal to 0.45%. The additive is a waste silica material having SiO2 content great than or equal to 96%. The composite additive is a mixture of lime milk, mill scales and calcium lignosulphonate. The silica brick for a glass furnace has high SiO2 content, a high yield, low impurity content, low apparent porosity, good high-temperature performances and a long service life. A preparation technology of the silica brick for a glass furnace is simple and is suitable for large-scale production.

Description

technical field [0001] The invention relates to the technical field of refractory materials, in particular to silica bricks for glass furnaces. Background technique [0002] Glass furnace is a kind of melting device that glass manufacturing industry must have. It is usually made of refractory materials. Its investment is relatively large, accounting for about 1 / 3 of the total investment. Its importance can be imagined. Silica brick is a kind of SiO 2 The acidic refractory material as the main component has the characteristics of high temperature volume stability, excellent acid corrosion resistance, and high load softening temperature. It is mainly used in coke ovens, glass furnaces and non-ferrous metal smelting, among which silica bricks used in glass furnaces As long as it is used for its crown, the top of the hanging wall, and the front and rear walls. [0003] At present, the technical indicators of domestic silica brick manufacturers are basically maintained at the t...

AI Technical Summary

Problems solved by technology

The high-quality silica bricks currently on the market have high residual quartz content (3%), high apparent porosity (21%), and high true density (2.34g / cm 3 ), etc., thereby limiting its service life in long-term high-temperature environments, especially in large glass melting furnaces and float furnaces

[0004] Chinese patent CN102126866A discloses a high-purity siliceous refractory material suitable for masonry superstructures of oxy-fuel combustion glass furnaces and its production process. The refractory material described in it is SiO 2 High-purity silica bricks with a content of 97~98%, with SiO 2 Crystalline silica with a content greater than 98% is aggregate, SiO 2 Vein quartz or SiO with a content greater than 99% 2 Crystalline silica with a content greater than 98% is used as the matrix, and 0.3-1.5% of calcium mineralizer, 0.1-0.6% of iron oxide or manganese oxide mineralizer, and 0.03-1.0% of polycarboxylic acid chemical admixture are added Composed of an appropriate amount of calcium lignosulfonate binder, it is made after compounding, kneading, molding, drying and sintering. The refractory material has excellent high temperature resistance and corrosion resistance. ≤21.5%, true density≤2.332g / cm 3 , normal temperature compressive strength ≥ 47.6MPa, it mainly has the following deficiencies: 1) It mainly emphasizes the dispersant effect of the dispersant on the mineralizer in the mud. According to the general refractory production process, it belongs to the pouring molding method, and the molding method is curing, Demoulding, the production cycle is longer than that of press molding, and the process is more cumbersome; 2) The patent does not mention issues such as product rate, service life and impurity content; 3) Its formula is complicated, the production process is cumbersome, and the production cost is relatively high

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