Which coal type is most commonly burned in steam generators (boilers)____________________?
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Answer: E. none of the above
Explanation
Steam generators in power plants primarily burn bituminous coals because of their high calorific value and availability. Since specific bituminous coal types vary by region and boiler design, broad categorical answers often apply in standards. Non-coking bituminous coal is specifically favored for pulverized fuel burners to prevent caking inside the combustion chamber. Coal is classified by its carbon rank, ranging from low-energy peat and lignite up to high-rank anthracite coals. Steam generators require reliable solid fuels that burn steadily and efficiently to produce high-pressure superheated steam. Bituminous coal possesses moderate to high heating values, making it the global standard fuel for thermal power generation.
Brown coal, or lignite, has high moisture content and low energy density, making it less ideal for high-capacity steam boilers. Peat represents the lowest rank of coal formation with excessive moisture, rendering it unsuitable for utility power generation. Coking bituminous coal tends to swell and agglomerate during heating, which can clog standard boiler grates if not pulverized.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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