Production Status and Development Prospect of Russian Casting Refractory Materials

Russia's fused cast refractory production accounts for only 2% of its shaped refractory production. However, due to its unique properties, fused cast refractories can be effectively applied to the lining of high temperature furnaces, especially in glass melting furnaces (production of flat glass, decorative glass, various containers, etc.). Depending on the structure of the glass furnace, the amount of refractory cast refractory material accounts for 40% to 80% of the refractory material. In addition, fused cast refractories can also be effectively used in glass plastics, basalt fiber, mineral wool, crystalline silicon and flux production equipment, as well as in efficient use of radioactive waste.

In the past 20 years, the production of fused cast refractories in Russia has been reduced by 30%. Currently only three companies produce fused cast refractories: Sherbinski fused refractory plant, РХИ ubdolski refractory plant and Doma Jedovs Based on electric melting products factory. The main technical equipment of these companies is backward and can only provide two types of refractory products: zirconium corundum products (3 models) and corundum products (2 models).

Therefore, at present, the domestic fused cast refractory materials in Russia cannot meet the requirements of Russian users in terms of output or product variety and quality. Most of the fused cast refractories used by enterprises rely on imports. Zirconium corundum refractory

Zirconium corundum fused cast refractory

Is the only fused cast refractory material (grades Бк-33, Бк-37, Бк-41) that can be mass-produced in Russia. Its chemical composition is the same as that of foreign products. It should be pointed out that the domestic fusion casting technology can still produce most of the fused cast refractories used in glass kiln, and its erosion resistance is at the same level as imported products. However, compared with similar products of major foreign companies, the main feature of the zirconium corundum products produced in Russia is that it is more likely to precipitate inclusions into the glass frit. Zirconium-corrugated bricks supplied by Chinese companies to the Russian market are also more likely to cause such defects, and products produced by Chinese companies licensed by SEPR and Monofrax have avoided these shortcomings. The reason for the high quality of zirconium corundum bricks produced by foreign companies is that they are produced in an electric arc furnace according to an oxidative melting process. The Shelbinski Electrolytic Material Plant has conducted industrial tests using an oxidative melting process to produce more than 1,000 tons of zirconium corundum products for use in flat glass production plants. In the 1990s, all work on the oxidative melting process was terminated due to changes in economic conditions.

Corundum refractory

Worldwide, corundum fused cast refractories are second only to zirconia corundum bricks in production and use. Due to its minimal possibility of depositing inclusions into the frit, the use of high quality cast-cast corundum bricks ensures a high quality of the glazing. PХИ Bodolski refractory is the only manufacturer of fused cast corundum refractories (КЭЛ-93 and КЭЛ-95) in Russia. The refractory material produced by the plant has been successfully applied to the lining of steel ingots and billet heat treatment furnace bottoms, but its application in glass melting furnaces is limited due to the high probability of depositing inclusions into the glass frit. Only the fused cast corundum refractory materials produced by foreign companies can meet the needs of glass manufacturers, especially optical glass, lighting glass and medical glass manufacturing enterprises. It should be noted that Russian domestic companies also have experience in producing cast-cast corundum products.

Casting corundum brick MK-1: In terms of microstructure, the article consists of approximately equal amounts of corundum crystals and a β-Al2O3 phase (containing Na2O·11Al2O3), and also contains a glass phase of about 2% φ. According to the test results of corrosion resistance and bubble precipitation probability, MK-1 refractory material is suitable for the production of electric vacuum borosilicate glass C52-1, optical glass and silicon microcrystalline glass kiln heating zone and glass melting furnace puddle zone lining. In order to industrially produce MK-1 cast-cast corundum bricks, Russia has specially formulated technical conditions TY1594-006-549103-2004: "Fused cast corundum bricks for glass melting furnaces".

Casting corundum spinel brick MK-4: This product contains (φ)% corundum (90), spinel (8) and glass phase (2). The product has high erosion resistance and low bubble precipitation rate, and is recommended for the boiling region of the BC-92 lead silicate glass melting furnace for producing optical fibers. This refractory material is also considered to be a suitable material for the production of melting furnaces for phosphate laser glass.

There is also a corundum spinel refractory MK-13 containing 85% (φ) corundum, 5% (φ) magnesium aluminum spinel, 5% (φ) oblique zircon and 5% (φ) glass phase. This product is suitable for use in the production of furnaces for soda lime silicate glass and electric vacuum borosilicate glass. The Sherbinski fused refractory plant industrially produced more than 80 tons of MK-13 refractories.

Chrome-containing refractory

Russia does not produce chrome-containing refractories, only Бакор Technology Center produces a small amount of granular chromium-containing refractory materials. Therefore, the chromium-containing refractories used in Russia are imported from abroad. The highest life-long chromium-containing refractories produced abroad are chromic oxide materials with a Cr2O3 content of 90.0% to 95.7%. Compared with ceramic refractories, the main advantage of smelting chromium-containing refractories is that they have a high-density structure and can produce large-sized products weighing up to 300 kg. The production technology for casting chromium-containing refractories is controlled by several foreign companies, such as SEPR (ER2161, Cr2O3 27%) and RHI (Monofrax K-3, Cr2O3 28%, Monofrax E, Cr2O3 75%). Russia's domestic Shelbinski fused refractory plant also has experience in producing chrome-plated refractories (ХАЦ-30 and ХЦ-45), but its corrosion resistance in alkali-free borosilicate glass pool is lower than that of foreign countries. Chromium oxide refractories, therefore, according to user requirements, the plant has developed high chromium fused cast refractories ХПЛ-85 and ХМГ (see Table 1). In the molten pool of alkali-free borosilicate E glass, mineral wool and basalt fiber production equipment, the corrosion resistance of ХПЛ-85 reaches the level of ceramic chrome refractory. ХМГ products are suitable for use in CHM-1000 lead-bismuth glass production furnace lining.

Russian domestic production companies can only guarantee the minimum demand for medium-grade quality cast-zirconium fused alumina bricks from Russian glass factories. The oxidized melt-cast zirconium corundum bricks required by the glass plant are all supplied by foreign companies. The fused cast corundum bricks used in the glass industry and the chrome cast bricks used in the chemical industry (produced by mineral fibers) are also all imported. Therefore, there is an urgent need to build a production line for such products in China. Most of the production processes for such products are studied by researchers in Russia, but foreign experience can also be used. In organizing large-scale production of zirconium corundum bricks and corundum bricks, the ideal method is to set up its production line in the largest refractory plant in the European part of Russia.

The price per ton of chromium-containing refractories produced abroad exceeds 25,000 euros. Therefore, the profit generated by the production of chromium-containing refractories in Russia is quite attractive.