Which of the following is excluded from the alumino-silicate refractory category ?
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Answer: C. Tar dolomite bricks
Explanation
Tar dolomite bricks are basic refractories composed primarily of calcium and magnesium oxides. Alumino-silicate refractories consist mainly of alumina and silica minerals like fireclay and mullite. Chemical composition clearly separates basic dolomite from the traditional alumino-silicate brick category. Alumino-silicate materials form a major class of refractories used across diverse industrial kilns. Dolomite refractories are basic materials sensitive to moisture and used in basic steel converters. Classification depends on the primary chemical oxides comprising the refractory grain matrix.
Matching refractory chemical properties with process slags prevents rapid corrosion and premature failure. Steelmaking vessels utilize basic refractories to withstand alkaline refining fluxes effectively. Alumino-silicate bricks are commonly employed in utility boilers, cement kilns, and reheat furnaces. Fireclay bricks belong to the alumino-silicate category containing balanced alumina and silica. Mullite bricks are high purity alumino-silicate refractories offering excellent high temperature stability. High alumina bricks are classified under the alumino-silicate system based on elevated alumina levels.
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- Engineering
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- Chemical Engineering
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- medium
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