Two stage hammer mill with particle separator

An apparatus for grinding a mixture of glass and contaminants and separating ground glass from contaminants which comprises:

• means for introducing glass and contaminants into a glass grinding chamber;
• a glass grinding chamber, operatively connected to said means for introducing glass and contaminants, for receiving glass and contaminants from said means for introducing glass and contaminants, said glass grinding chamber having a hammer mill therein including a plurality of rotating radially disposed members for impacting, entraining in air, and grinding, glass and contaminants;
• a separation chamber having an inlet port, a separation loop and a return port, with said inlet port in pneumatic communication with the glass grinding chamber at a predetermined upper elevation, for receiving centrifugally thrown ground glass and contaminants, entrained in air, from the glass grinding chamber and into the separation loop, and with said return port connected to said glass grinding chamber, at a lower elevation for returning ground glass and contaminants, of larger than a predetermined size, from the separation loop to said glass grinding chamber for further grinding;
• means for controlling the rate of flow of entrained ground glass and contaminants from the glass grinding chamber into the separation chamber;
• means for reducing the velocity of entrained ground glass and contaminants to allow larger particles of ground glass and contaminants to fall out of air entrainment within the separation loop and onto a shaker screen;
• a vacuum lift off being operatively positioned within the separation chamber to remove a portion of the air entrained ground contaminants from within the separation loop;
• means for shredding entrained contaminants within the separation loop;
• a shaker screen assembly being attached to the separation chamber and positioned to receive ground glass and contaminants falling out of entrainment within the separation loop, said assembly having a vibratable shaker screen for passing ground glass and contaminants smaller than a predetermined size through the shaker screen assembly;
• and
• a cyclone separator, being positioned to receive ground glass and contaminants passed through the shaker assembly, for separating the contaminants from the ground glass.