Method and apparatus for comminuting material in a re-entrant circulating stream mill
AssigneeNorandy, Incorporated
InventorNorwood H. Andrews
Life of this patent
Estimating the term…
Abstract
A re-entrant circulating stream mill vents a part of the circulating stream adjacent the annular peripheral wall of the mill directly to the junction in each of a plurality of sets of pressure nozzles and cooperating acceleration tubes which are used to form the circulating stream. Each pressure nozzle provides a high velocity gaseous jet stream that entrains material as it enters the acceleration tube where the material is accelerated to its maximum velocity before it is discharged into the vortex chamber of the mill and impacts upon the circulating stream adjacent the annular peripheral wall of the vortex chamber. The apparatus also takes advantage of the comminution of the material which takes place in the acceleration tube.
Claims14
Apparatus for comminuting material to a finely divided form, comprising:
- a re-entrant circulating stream comminuting mill,
- said comminuting mill including a chamber having a generally annular peripheral wall,
- a plurality of spaced gaseous fluid means for discharging gaseous fluid streams through said wall into said chamber with both a component of movement forward in the direction of circulation and a radial component of movement relative to a central axis of said peripheral wall to form a circulating vortex in said chamber,
- said gaseous fluid means comprising, in tandem, a gaseous pressure nozzle for accelerating the gaseous fluid, and acceleration tube means for directing the accelerated gaseous fluid into said chamber.
- transfer means for transferring circulating fluid and entrained material from said chamber directly to each junction of said pressure nozzle and acceleration tube means whereby said circulating fluid and entrained material are drawn to said junction by the difference in pressure between said junction and the chamber and is thereafter accelerated within said acceleration tube means and projected back into said chamber,
- and material feed means and material outlet means for said mill.
In an apparatus for comminuting material to a finely divided form, comprising:
- a re-entrant circulating stream comminuting mill,
- said comminuting mill including a chamber having a generally annular peripheral wall,
- a plurality of spaced gaseous fluid means for discharging a stream of gaseous fluid through said wall into said chamber with both a component of movement forward in the direction of circulation and a radial component of movement relative to a central axis of said wall to form a circulating vortex in said chamber,
- material feed means and material outlet means for said mill,
- the improvement being wherein at least a plurality of said gaseous fluid means each comprise, in tandem, a pressure nozzle for accelerating gaseous fluid and acceleration tube means for directing accelerated gaseous fluid into said chamber, and
- transfer means for transferring circulating fluid and entrained material directly from said chamber to each junction of said pressure nozzle and acceleration tube means, whereby said circulating fluid and entrained material are drawn to said junction by the difference in pressure at said junction and the chamber and thereafter accelerated within said acceleration tube and projected back into said chamber.
A process for comminuting material to a finely divided form, comprising:
- generating a circulating gaseous stream within a closed annular chamber using a plurality of spaced gaseous fluid means for discharging streams of gaseous fluid through said wall into said chamber with both a component of movement forward in the direction of circulation and a radial component of movement relative to a central axis of said chamber to form a circulating vortex in said chamber,
- generating said stream of gaseous fluid by generating a high velocity gaseous jet in a pressure nozzle and then passing the jet stream through an acceleration tube into said chamber,
- feeding material to be comminuted into said chamber,
- transferring circulating fluid material from the chamber to the junction of said pressure nozzle and said acceleration tube, and then accelerating said material within said acceleration tube and projecting it back into said chamber,
- and withdrawing finished material from said chamber.
Dependencies are inferred from the claim text.