What operational problems are caused by sulfur impurities in coal___________________?
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Answer: E. all of the above
Explanation
Sulfur content in coal reacts during combustion to form corrosive chemical compounds and low-melting slag deposits. Acidic sulfur dioxide gases condense at lower temperatures, leading to severe cold-end corrosion in downstream boiler air heaters. High sulfur levels catalyze exothermic oxidation reactions that promote dangerous spontaneous combustion events within stored coal piles. Coal is a complex fossil fuel containing variable mineral impurities, including inorganic and organic sulfur compounds. Combustion processes convert fuel-bound sulfur primarily into sulfur dioxide and minor amounts of sulfur trioxide emissions. Clinkering occurs when low-melting ash constituents fuse together into solid masses inside high-temperature furnace grates.
Option A lists only clinkering and slagging while ignoring corrosion and storage fire risks caused by sulfur. Option B focuses solely on air heater corrosion without addressing furnace ash fusion problems. Option C highlights storage combustion hazards while omitting operational furnace slagging and emission issues.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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