Oliver Hi-Cap N Series, Operation Manual

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Figure 4: Sectional view of stoner deck operation
This figure 4 above is a sectional diagram of what occurs on a stoner deck.
Compressed air forced through the mesh of the deck cover lifts the lighter particles
upward, while heavier particles sink against the air currents and come to rest on
the deck surface, providing the air is properly adjusted. The heavier particles are
forced to travel uphill by mechanical action, while the lighter particles float
downhill on a film of air.
While stoners have greater capacities than gravity separators, based on
square feet of relative deck area, there is a limit as to the amount of feed flowing
to the deck. As the feed is increased, the stratifying area is also increased. The
stratifying area should not occupy more than 1/3 of the entire deck area.
We have already stressed the need for earlier processing of products before
they are introduced onto the stoner. (See p. 1.). This pre-sorting enables
separations that are otherwise impossible. There are three guide- lines developed
by the late Oliver W. Steele that state what can be separated and what cannot be
separated on a gravity separator or stoner.