Which equipment is utilized industrially for calcining limestone and dolomite?
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Answer: B. Moving bed reactor
Explanation
Moving bed reactors allow continuous solid flow countercurrent to hot rising combustion gases. Calcination requires sustained high temperatures to decompose carbonate rocks into metal oxides. Continuous solids handling makes moving bed reactors ideal for large-scale mineral processing. Calcination involves heating solid minerals to drive off carbon dioxide or water molecules. Limestone decomposes into calcium oxide and carbon dioxide gas when heated strongly. Moving bed reactors process granular solids smoothly through gravity flow and mechanical discharge.
Cement manufacturing plants rely on large vertical kilns to calcine vast quantities of limestone. Metallurgical industries produce quicklime efficiently using continuous moving bed thermal reactors. Optimizing solid residence time ensures complete thermal decomposition of raw carbonate minerals. Fluidized bed reactors risk particle agglomeration and are less common for traditional lime calcination. Fixed bed reactors operate batchwise, making them inefficient for continuous industrial mineral processing. Stating none of these is incorrect since moving bed reactors are standard industrial equipment.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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