What key compositional parameters are provided by a proximate analysis of solid fuel__________________?
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Answer: D. fuel constituents as percents by weight of moisture, volatile, fixed carbon and ash
Explanation
A proximate analysis determines the percentages by weight of moisture, volatile matter, fixed carbon, and ash in a solid fuel. This standardized laboratory procedure measures key constituent fractions that dictate how coal burns in industrial furnaces. Weight percentages obtained from proximate analysis help engineers evaluate coal grade, combustion behavior, and boiler sizing. Proximate analysis is a practical assay rather than an elemental chemical breakdown of fuel components. Volatile matter represents gases driven off when heating coal without oxygen, while fixed carbon remains as solid char. Ash content measures the incombustible mineral residue left behind after complete combustion of the fuel sample.
Expressing chemical constituents as percentages by volume is incorrect because proximate analysis results are measured and reported by weight. Elemental constituents like carbon, hydrogen, and oxygen are determined through ultimate analysis rather than proximate analysis. Moisture and ash-free heating values are derived calculations rather than the direct weight-percentage constituents of proximate analysis.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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