Waste pulping and liquid extraction system and method including automatic bag feeding

In a waste handling system, liquid extraction apparatus for removing liquid from a mixture of liquid and solids, comprising:

• an input port for providing the mixture of liquid and solids;
• a stationary helical screw having a discharge end;
• detachable means for supporting the discharge end of the screw;
• a sieve having a cylindrical sieve surface surrounding the screw, the sieve rotatably mounted to the input port;
• and
• means for rotating the sieve about the screw to move the solids along the screw longitudinally towards the discharge end, the rotating means including a rotatable collar, the collar including means for transmitting torque to rotate the sieve, wherein the sieve and the screw are slidably mounted to the input port and slidably removable from the apparatus by pulling the sieve and the screw through the collar.

Waste pulping and liquid extraction apparatus, comprising:

• a tank for containing liquid and solids having an input port for receiving liquid, a rotary disc impeller mounted therein for grinding the solids to form a mixture of liquid and solids;
• a stationary helical screw horizontally mounted directly to the tank and having a receiving end adjacent to the tank and a discharge end, the tank including means for conducting the mixture to the receiving end;
• a sieve having a cylindrical sieve surface surrounding the screw through which the liquid drains, the sieve rotatably mounted to the tank;
• means for rotating the sieve about the screw to move the solids longitudinally towards the discharge end;
• a housing surrounding the sieve and mounted directly to the tank for communicating liquid that drains from the sieve back to the tank by way of the input port;
• and
• means coupled to the housing for supporting the discharge end of the screw.

Waste pulping apparatus comprising:

• a rotary disc impeller;
• a sieve ring encircling the impeller and having a central axis;
• first shearing means secured to the sieve ring and having a straight cutting edge that is parallel to the axis;
• ramp means secured to the sieve ring and adjacent to the first shearing means for deflecting unpulpable material;
• second shearing means secured to the impeller and having a plurality of shearing members, each shearing member having a beveled cutting edge for periodically coming into play with the straight cutting edge, the shearing member inclining towards the sieve ring and the beveled cutting edge inclining in the direction of rotation of the impeller so that unpulpable material is pushed above the second shearing means and away from the impeller, the beveled cutting edge having a helical shape to maintain a substantially uniform radial distance between the beveled cutting edge and the straight cutting edge as the beveled cutting edge and the straight cutting edge come into play.

Waste pulping apparatus handling food waste and food handling waste, comprising:

• a rotary disc impeller;
• a sieve ring encircling the impeller and having a central axis;
• first shearing means secured to the sieve ring and having a straight cutting edge that is parallel to the axis;
• second shearing means detachably secured to the impeller and having a plurality of shearing members, each shearing member having a beveled cutting edge for periodically coming into play with the straight cutting edge, the shearing member inclining towards the sieve ring and the beveled cutting edge inclining in the direction of rotation of the impeller so that unpulpable material is pushed above the second shearing means and away from the impeller, the beveled cutting edge having a helical shape to maintain a substantially uniform radial distance between the beveled cutting edge and the straight cutting edge as the beveled cutting edge and the straight cutting edge come into play,
• wherein at least one of said shearing members has an extension member extending outside of the sieve ring, the extension member positioned along a diameter approximately 1.5 times a diameter of the sieve ring.