A size reduction circuit processing a 100 to 300 mm feed down to 10 to 50 mm falls under _____________ crushing?
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Answer: B. Secondary
Explanation
Secondary crushing steps accept material ranging from one hundred to three hundred millimeters. The output size is successfully reduced down to ten to fifty millimeters. This intermediate reduction stage bridges primary crushing and fine grinding. Mineral processing circuits use staged size reduction to handle run-of-mine ores. Primary crushers take raw boulders while secondary crushers handle smaller rocks. Cone and roll crushers are commonly deployed for secondary size reduction duties.
Quarrying operations rely on secondary crushers to produce graded construction aggregates. Cement plants crush quarried limestone through secondary stages before fine grinding. Proper sizing prevents overloading downstream ball mills and grinding equipment. Primary crushing handles much larger run-of-mine feed sizes directly from blasting. Fine crushing processes much smaller feed sizes down to microscopic dimensions. Ultrafine milling produces sub-micron powders rather than centimeter-scale particles.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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