Difficulty: Easy
Correct Answer: classification
Explanation:
Introduction / Context:
Solid–fluid separations employ different driving forces and mechanisms. When particles settle at different velocities in a fluid, engineers can exploit these differences to separate or grade materials.
Given Data / Assumptions:
Concept / Approach:
Classification uses fluid flow and gravity to separate particles into size (and sometimes density) fractions. Hydraulic classifiers, cyclones, and elutriators are examples. Thickening and clarification focus on concentrating a slurry or producing clear overflow, not on sharp size grading; flotation relies on surface chemistry and air attachment, not settling alone.
Step-by-Step Solution:
Identify mechanism: settling-driven velocity differences.Name of process: classification.Select “classification.”
Verification / Alternative check:
Cut sizes in classifiers reflect balance between settling velocity and upward fluid velocity; process design targets desired size splits accordingly.
Why Other Options Are Wrong:
Froth flotation uses hydrophobicity, not settling.Thickening/clarification emphasize concentration/clarity rather than size separation into multiple fractions.
Common Pitfalls:
Assuming any gravity settler is a classifier; many settlers are designed for clarification rather than controlled cut points.
Final Answer:
classification
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