Transporting pulverized coal through pipes to boiler burners utilizes preheated air restricted to a maximum of roughly 300° C to prevent___________________?
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Answer: B. Risk of explosion
Explanation
Transporting pulverized coal in hot air streams requires strict temperature control to prevent premature fuel ignition. Exceeding critical temperature thresholds triggers rapid oxidation and catastrophic dust explosions inside transport pipes. Maintaining air temperatures below three hundred degrees Celsius ensures safe pneumatic conveying to the boiler burners. Pneumatic transport systems blow pulverized coal mixtures through steel pipes directly into utility boiler furnaces. Fine coal dust possesses an extremely high surface-to-volume ratio, making it highly reactive with heated oxygen. Safety protocols in thermal power plants mandate continuous temperature monitoring of primary air and coal mixtures.
Large combustion chambers are required for complete fuel burnout rather than preventing pneumatic transport explosions. Clinker formation occurs on furnace walls and grates due to molten ash rather than primary air transport temperatures. Incomplete combustion results from insufficient oxygen or poor mixing rather than limiting the primary air temperature.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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