Screen capacity is commonly reported as a mass flux per screening area. Which unit correctly expresses screen capacity?

Introduction / Context:
To compare screens of different sizes, capacity must be normalized by area. The industry standard metric is mass throughput per unit area of screening surface.

Given Data / Assumptions:

• “Capacity” refers to the throughput rate normalized by area, not merely total feed.

Concept / Approach:
Total throughput (t/h) alone does not permit fair comparison across screens of different areas. The correct unit is t/h per ft^2 (or t/h per m^2 in SI), often called unit screen capacity. This helps in sizing and vendor comparison.

Step-by-Step Solution:
Define capacity basis: mass flow divided by screen area.Select the option that includes both time and area: t/h·ft^2.

Verification / Alternative check:
Design charts plot unit capacity versus aperture, slope, and material factors.

Why Other Options Are Wrong:
t/h or t/ft^2 alone omits the other needed dimension.

Common Pitfalls:
Using overall t/h for selection can oversize or undersize the screen when area changes.

Final Answer:
tons per hour per square foot (t/h·ft^2)