1. Equipment Overview

Double-cone Rotary Vacuum Dryer (SZG Series)
An intermittent, vacuum-conduction drying equipment with a rotating container, widely used in fine chemical industries. It is commonly compared with vacuum paddle dryers and vacuum ovens for selection.
The unit features a double-cone-shaped rotating chamber, which rotates slowly as a whole. Heat transfer medium flows through the jacket to provide heating. The interior has no stirring shaft or internal rake teeth.

II. Structural Composition

1. Double-cone cylinder: Made of 304/316L stainless steel with jacket; supported by shafts at both ends; smooth internal surface without dead corners for easy cleaning; equipped with manholes, material inlet, and vacuum port on the cylinder.

2. Support and rotary drive mechanism: Motor + gearbox drives the cylinder to rotate slowly in forward and reverse directions; equipped with braking and positioning function.

3. Vacuum rotary joint: Installed on the hollow support shaft, extracts steam from inside the cylinder while maintaining a tight vacuum seal during rotation.

4. Vacuum system: Comprising vacuum pump, condenser, solvent recovery tank, and dust collector.

5. Control system and insulation layer; optional explosion-proof design, CIP cleaning, and spray device.

III. Working Principle

1. Powder or filter cake material is loaded into the double-cone tank, and the manhole is sealed;
2. Steam, hot water, or thermal oil is circulated through the jacket to indirectly heat the material via the tank wall;
3. The tank rotates slowly (4–10 r/min), causing the material to continuously tumble and mix under gravity, with the heated surface constantly renewed;
4. A high vacuum (-0.085 to -0.098 MPa) is drawn inside the tank, enabling low-temperature evaporation of solvents/water;
5. Vapor is extracted through the hollow shaft and rotary joint, then condensed in a condenser for recovery of organic solvents;
6. After drying is complete, heating is stopped, temperature is reduced, vacuum is released, and the tank rotates to position the discharge port downward for unloading.