The grindability index of any material is independent of its_____________________?
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Answer: D. Size
Explanation
The grindability index of any material characterizes its intrinsic hardness, toughness, and resistance to fracture. Standard material properties like elasticity and hardness dictate how much energy is needed for comminution. The grindability index remains a material-specific constant that is entirely independent of initial particle size. Grindability tests measure the relative ease with which a solid material can be pulverized in milling equipment. Material science principles govern how crystal structures absorb and dissipate mechanical fracture energies. Standardized laboratory tests provide reproducible grindability indices for engineering design calculations.
Power plant engineers use coal grindability indices to predict pulverizer performance and boiler fuel capacities. Mineral processing plants evaluate ore grindability to size ball mills and estimate electrical power demands. Understanding material hardness ensures that comminution machinery is selected correctly for specific rock types. Option A elasticity influences energy storage before fracture, directly affecting the grindability index. Option B hardness is a primary physical property that dictates the numerical value of the grindability index. Option C toughness determines resistance to impact fracture, which is inherently captured by grindability testing.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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