Hammer mills reduce particle size through a combination of impact and attrition occurring between the________________?
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Answer: C. Both A. and B.
Explanation
Hammer mills achieve size reduction through both direct impact by the rotating hammers and attrition between particles. High-speed steel hammers shatter feed material upon initial contact through violent mechanical impact forces. Additional comminution occurs as particles rub against each other and grind against the internal housing walls. A hammer mill consists of a high-speed rotor turning inside a heavily reinforced cylindrical steel housing. Screen plates mounted at the bottom of the casing control the maximum particle size of the discharge. Brittle and fibrous materials respond exceptionally well to the high-intensity shock loads generated inside the mill.
Option A is partially correct but ignores the significant size reduction happening through interparticle collision and friction. Option B is also incomplete because direct hammer impact provides the primary shattering force during operation. Option D is incorrect since both listed mechanisms actively contribute to comminution inside the mill.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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