Vertical-shaft airlock

A rotary valve, comprising:

• a) a rotor assembly rotatable by a driver to cause material to be transferred from an inlet side to an outlet side of the rotary valve, the rotor assembly including a rotor coupled to a shaft which rotates about an axis when driven by the driver, the rotor including:
• an outer tube,
• an inner tube,
• a plurality of radial blades, wherein the outer tube, inner tube, and radial blades are all of substantially the same height and the radial blades extend between the outer and inner tubes and are connected thereto to define a plurality of pockets between the outer and inner tubes, the pockets being open at a top and a bottom of the rotor, and
• a hub connected to the inner tube and coupled to the shaft;
• b) a casing assembly for supporting the rotor assembly, and including an inlet for allowing the material to enter the pockets of the rotor assembly and an outlet for allowing the material to exit the rotor assembly, the casing assembly including:
• an upper cap disposed at a top of the casing assembly that contains an opening for allowing the material to enter the pockets of the rotor assembly, a shaft opening, and a wiper assembly that removes material from the blades as the blades pass by the inlet opening,
• a sleeve coupled to the upper cap, the sleeve being shorter than the rotor, and
• a lower cap disposed at the bottom of the casing assembly that contains an opening for allowing the material in the pockets of the rotor assembly to exit,
• wherein the lower surface of the upper cap conforms to the shape of the top of the rotor and the upper surface of the lower cap conforms to the shape of the bottom of the rotor;
• c) a plurality of springs coupling the lower cap to the sleeve that serve to compress the rotor between the caps;
• and
• d) a bearing assembly for rotatably supporting the rotor inside the casing assembly, comprising an upper bearing which separates the upper cap from the top of the rotor by a minimum gap, a lower bearing which separates the lower cap from the bottom of the rotor by a minimum gap, and bearing grooves in which the bearings are disposed.