摘要 |
Prior to entering a tumbling media mill grinding chamber, feed containing clumps of adherent fine and coarse particles is brought into jarring contact with a moving member for liberating fine particles. Liberated fines are contacted, outside the chamber, with a current of gas to remove them from the remainder of the feed. At least a portion of this remainder enters a bed of charge material in the chamber and is ground with the media. When an indicator of a developing or existing over-fed or under-fed condition in the bed is sensed, adjustment of the jarring intensity, of the gas velocity or of both is made in response to the indicator for increasing and decreasing the quantity of fine particles removed from the feed. A clump separator, having an enclosure, jarring member and coarse solids outlet, may be used to liberate fines. This outlet is connected with a coarse solids inlet to the chamber. A path other than the coarse solids outlet is provided for removing liberated fine particles from the enclosure. A control, responsive to the indicator, increases and decreases the quantity of fine particles removed via this path. Preferably the enclosure is a duct, the jarring member rotates in the duct, the member is below and spaced from a duct feed inlet through which the duct receives the feed, and an entrainment gas supply conduit is connected with the duct for maintaining an upwardly flowing gas current through the jarring member and beyond the duct solids inlet.
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