Methods for recrushing rocks and removing fines therefrom
AssigneeVulcan Materials Company
InventorMitchell L. Whittaker
Life of this patent
Estimating the term…
Abstract
Crushed rock is produced by passing rocks through an early stage rock crusher. Crushed rocks that exit the early stage rock crusher are passed across a sizing device. Rocks failing to pass completely through the sizing device are recrushed in a later-stage rock crusher and then passed downwardly through a high-volume air stream which flows within the crusher transversely through the downwardly traveling crushed rocks and extracts fines therefrom prior to exiting of the crushed rocks from the crusher. The fines extracted by the air stream are at least 50% minus 50-mesh.
Claims13
A method of providing crushed rock, comprising the steps of:
- A. passing rocks through an early-stage rock crusher;
- B. passing crushed rocks from the early-stage rock crusher to a sizing device;
- C. recrushing, in a later-stage rock crusher unit, rocks from step B that fail to pass completely through the sizing device;
- D. constraining the recrushed rocks to gravitate downwardly toward an exit of the later-state rock crusher unit in the form of a column of recrushed rocks;
- E. providing first and second air ports on opposite sides of the recrushed rock column wherein the first air port communicates with ambient air;
- and
- F. generating suction at a location downstream of the second air port which communicates with the second air port, to cause ambient air to be sucked transversely through the recrushed rock column from the first air port to the second air port to extract fines from the recrushed rock column prior to the recrushed rocks exiting the later-stage crusher unit.
Dependencies are inferred from the claim text.