Apparatus for producing waste compressed solid

An apparatus for producing a waste compressed solid comprising:

• a hopper comprising an opening for receiving a waste in an upper side thereof and a discharge port in a bottom side thereof;
• a feed screw conveyor for feeding the waste in the hopper to the discharge port;
• a draw screw conveyor for drawing the waste in the hopper to a neighbor of the feed screw conveyor from both sides thereof, the draw screw conveyor having a shaft crossing close to a shaft of the feed screw conveyor and being alternately rotatable in both directions;
• a compression chamber comprising a supply port communicated with the discharge port of the hopper and a take-out port for the waste;
• a movable piston compressing the waste in the compression chamber;
• and
• a draw motor control unit controlling a rotation of the draw screw conveyor in correspondence to the feed screw conveyor, the rotation being controlled in a drawing direction when the feed screw conveyor rotates in a feeding direction and the rotation being controlled opposite to the drawing direction or to be stopped when the feed screw conveyor rotates opposite to the feeding direction;
• wherein:
• the draw screw conveyor is a pair of screw conveyors symmetrical to each other relative to an axis of the feed screw conveyor and rotations of the pair of screw conveyors are independently controlled by the draw motor control unit.