Multi-plate or laminated screw press

A multi-plate screw press for dewatering sludges, comprising:

• a plurality of first movable closed rings, each including an upper hole and a lower hole, the plurality defining a first movable closed ring group;
• a plurality of second fixed closed rings, each including four holes, the plurality defining a second fixed closed ring group;
• wherein the plurality of first movable closed rings and the plurality of second fixed closed rings are arranged adjacent to each other in an alternating fashion, collectively defining an elongate longitudinal filtration cavity open at each end, one end of the filtration cavity is configured as a feeding end, and the other end of the filtration cavity is configured as a discharging end, the feeding end is provided with a sludge feeding box, and the discharging end is provided with a sludge discharging box;
• a first gasket provided between adjacent first movable closed rings;
• a second gasket provided between adjacent second fixed closed rings;
• wherein a thickness of the first gasket is greater than a thickness of each of the plurality of second fixed closed rings, and a thickness of the second gasket is greater than a thickness of each of the plurality of first movable closed rings such that a gap is formed between adjacent first movable closed rings and between adjacent second fixed closed rings respectively;
• at least one spiral shaft extending through the elongate longitudinal filtration cavity;
• a plurality of supporting plates connected to each of the second fixed closed rings to keep them fixed, an upper end of each of the plurality of supporting plates is provided with a first opening;
• a driving device comprising:
• a primary driving rod, a middle section of the primary driving rod is detachably fixed on front and rear sides of the first opening of a respective supporting plate through a pair of U-shaped shaft sleeves, wherein the pair of U-shaped shaft sleeves are buckled oppositely to form a round hole in which the primary driving rod is sleevedly arranged;
• a secondary driving rod;
• a positioning rod;
• at least one eccentric device;
• and
• a movable transmission ring comprising a driving plate integrally formed with each of the plurality of first movable closed rings, each including a respective upper hole and lower hole;
• wherein:
• the primary driving rod is operably connected to a drive motor, the primary driving rod is supported by at least two of the plurality of supporting plates, and the primary driving rod includes the at least one eccentric device, the primary driving rod is arranged above the secondary driving rod, each at least one eccentric device is connected to a corresponding one of the plurality of first movable closed rings through the driving plate, an upper end of the driving plate is provided with a second opening;
• the secondary driving rod sleevedly extends through the upper hole of each of the first movable closed rings, the at least one eccentric device on the primary driving rod is connected to the secondary driving rod through the first movable closed ring group;
• the positioning rod sleevedly extends through lower hole, end of the plates of each of first movable closed ring piece group, such that the plurality of first movable closed rings in the first movable closed rings group are connected as a whole, and arranged in a first avoidance hole of each of the plurality of supporting plates;
• and
• wherein the first movable closed ring group is configured to be collectively moved by the driving device to move relative to the second fixed closed ring group that is fixedly connected to the plurality of supporting plates to keep fixed, to render the gap blocked or unblocked.