Mill

A mill for reducing the size of raw mining materials, comprising:

• a housing having a first end portion, a second end portion opposite the first end portion and separated from the first end portion by a mill length in a longitudinal direction, and a lateral area disposed between the first end portion and the second end portion, the housing including:
• a material inlet;
• an air inlet;
• a material outlet, wherein a portion of the material outlet has a volute shape;
• and
• a recirculated material inlet, wherein each of the material inlet, the air inlet and the recirculated material inlet are positioned near the first end portion, and wherein the material outlet is positioned near the second end portion;
• and
• an impeller positioned within the housing,
• wherein the impeller includes:
• a shaft disposed along a longitudinal axis and extending in the longitudinal direction between the first end portion and the second end portion;
• a plurality of impeller blade supports extending radially from the shaft and positioned spaced apart along the shaft;
• and
• a plurality of impeller blades mounted to the plurality of impeller blade supports and radially spaced apart from the shaft, each of the plurality of impeller blades extending in the longitudinal direction and mounted to each of the plurality of impeller blade supports;
• wherein each of the plurality of impeller blades forms a cross section having a concave impacting surface oriented towards a rotational direction of the plurality of impeller blades;
• wherein a cross section of the lateral area is a polygon including a plurality of lateral faces, the cross section of the lateral area having a centroid;
• wherein the shaft passes through the centroid;
• and
• wherein the air inlet is positioned adjacent to the shaft.

A mill for reducing the size of raw mining materials, comprising:

• a housing having a first end portion, a second end portion opposite the first end portion and separated from the first end portion by a mill length in a longitudinal direction, and a lateral area disposed between the first end portion and the second end portion, the housing including:
• a material inlet;
• an air inlet;
• a material outlet, wherein a portion of the material outlet has a volute shape;
• and
• a recirculated material inlet, wherein each of the material inlet, the air inlet and the recirculated material inlet are positioned near the first end portion, and wherein the material outlet is positioned near the second end portion;
• and
• an impeller positioned within the housing,
• wherein the impeller includes:
• a shaft disposed along a longitudinal axis and extending in the longitudinal direction between the first end portion and the second end portion;
• a plurality of impeller blade supports extending radially from the shaft and positioned spaced apart along the shaft;
• and
• a plurality of impeller blades mounted to the plurality of impeller blade supports and radially spaced apart from the shaft, each of the plurality of impeller blades extending in the longitudinal direction and mounted to each of the plurality of impeller blade supports;
• wherein each of the plurality of impeller blades forms a cross section having a concave impacting surface oriented towards a rotational direction of the plurality of impeller blades;
• wherein the housing includes a plurality of support ribs;
• wherein the housing includes a plurality of wear plates, the wear plates being substantially planar;
• and
• wherein the plurality of wear plates are connected to the inner surface of the lateral area.