Difficulty: Easy
Correct Answer: coal
Explanation:
Introduction / Context:
Different size-reduction machines target specific materials and duties. The Bradford breaker is a rotating cylindrical screen with internal lifters used primarily in the coal industry for sizing and cleaning.
Given Data / Assumptions:
Concept / Approach:
Run-of-mine coal often contains shale, stone, and out-of-seam dilution. As the breaker lifts and drops the feed, friable coal fractures and passes through apertures, while harder, larger rock is carried to the discharge for rejection or further handling. This selective action is suited to coal, not to materials like wheat, talc, or dense ores.
Step-by-Step Solution:
Recognize machine geometry: rotating, lifting, screening action.Match to an application needing simultaneous size reduction and cleaning.Coal preparation fits best; select “coal.”
Verification / Alternative check:
Coal preparation texts describe Bradford breakers as common for crushing and deshaling at mine sites.
Why Other Options Are Wrong:
Talc: requires fine milling (e.g., ball mill), not a breaker.Iron ore: breakage requires crushers; screening/beneficiation uses other equipment.Wheat: handled by mills or rollers in food processing.
Common Pitfalls:
Confusing Bradford breaker with rotary breakers used for municipal waste; while similar, classic Bradford service is coal.
Final Answer:
coal
Discussion & Comments