What role does grog play in refractory manufacturing __________________?
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Answer: D. All A., B. and C.
Explanation
Grog consists of previously fired firebricks crushed down into specific granular aggregate size distributions. This recycled material contains a stable mineral mixture of alumina and silica components. As a non-plastic ingredient, grog controls drying shrinkage and prevents cracking in green refractory shapes. Refractory grog is produced by grinding scrap fireclay bricks or specially calcined raw clays. Plastic clays shrink excessively during drying, necessitating the addition of inert non-plastic grog. Aggregates form the skeleton of refractory bricks, providing structural backbone during forming and drying.
Brick manufacturing plants blend grog with raw plastic clays to maintain precise dimensional tolerances. Using crushed pre-fired materials reduces manufacturing waste and recycles defective refractory products. Optimizing aggregate grading improves the thermal shock resistance and density of finished firebricks. Option A correctly names constituents but fails to capture its crushed pre-fired aggregate nature. Option B describes crushed firebrick but omits its alumina-silica chemical composition. Option C identifies it as non-plastic but misses the details regarding its mineral and recycled origin.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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