Which of the following operational factors will INCREASE the separation effectiveness of an oscillating seed-cleaning screen?
Options:
(A) Maintaining an optimal, shallow bed depth that allows every particle repeated contact with the screen aperture
(B) Operating at moisture contents well below the critical stickiness point to prevent aperture blinding
(C) Overloading the screen well beyond rated capacity to force particles through the perforations by overburden pressure
(D) Applying an appropriate deck stroke frequency and amplitude to fluidize and stratify the seed layer
Answer Key:
A, B, D
Step-by-Step Solution & Explanation
Screen effectiveness increases with proper stratification (D), shallow bed depth ensuring adequate contact chances (A), and dry grains that do not agglomerate or blind openings (B). Overloading (C) creates a thick bed where undersize particles never reach the screen surface, sharply reducing effectiveness.