What does ASTM rank (64-132) coal signify regarding a carbon content of 64%___________________?
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Answer: A. Fixed carbon and having a heat value of 13, 200 BTU/1b
Explanation
The ASTM classification system utilizes hyphenated numbers for coal rank categorization. The first number indicates the fixed carbon percentage on a dry mineral matter free basis. The second number represents the gross calorific value in units of BTU per pound. ASTM stands for American Society for Testing and Materials coal classification standards. Proximate and ultimate analyses provide the necessary data for ranking coal types. Calorific value determines the thermal energy released during complete combustion of fuel.
Power plant operators use ASTM coal ranks to select appropriate fuel specifications. Coal trading markets rely on standardized ranking to determine economic valuation. Boiler design engineers require accurate heating values to calculate thermal efficiency. Ash content is a separate proximate analysis parameter not represented in this ranking format. Low heating values like 132 BTU per pound are physically impossible for commercial coal. Incorrect parameter pairing confuses fixed carbon with ash or moisture constituents.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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Answer: A. Fixed carbon and having a heating value around 13, 200 BTU/1b
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