Mineral processing terminology: The crushed material sent to a separation unit is called the feed or ________.
Correct Answer: Heading (heads)
Introduction / Context:In ore dressing and coal preparation, standard terms describe material streams: feed, concentrate, tailings, and middlings. Familiarity with this vocabulary is necessary to read flowsheets, material balance tables, and plant reports without ambiguity.
Given Data / Assumptions:
- We refer to classic mineral processing nomenclature.
- The stream in question is the incoming material to a separator.
Concept / Approach:The incoming stream is “feed,” often also called “heads” or “heading” in some texts. “Concentrate” denotes the valuable product with enriched mineral content; “tailings” are the waste fraction; “middlings” are intermediate-grade streams that may require recycle. Therefore, the term that pairs with feed in this context is heads/heading.
Step-by-Step Solution:
Identify the stream position: input to separation → feed.Recall synonym: feed ≈ heads/heading.Select “Heading (heads).”Verification / Alternative check:Historical flotation and gravity separation literature commonly uses “heads” analysis to denote the feed assay, in contrast to concentrate and tailings assays.
Why Other Options Are Wrong:
- Tailing: waste output.
- Concentrate: valuable product.
- Middling: intermediate grade requiring retreatment.
- Refuse: generic waste, not the feed stream.
Common Pitfalls:Mixing up “head grade” (feed assay) with “concentrate grade,” leading to incorrect recovery calculations.
Final Answer:Heading (heads)