I. Temperature and Vacuum Control
1. Strictly control the heating medium temperature between 50°C and 80°C, ensuring the overall material temperature does not exceed 80°C to avoid the risk of thermal decomposition.
2. Maintain a stable vacuum level within the cylinder between -0.07 and -0.098 MPa; this allows moisture to vaporize rapidly at 40°C, enabling low-temperature drying.
3. Limit axial and radial temperature differences within the material to ±2°C to prevent localized instantaneous hot spots, which could cause scorching or loss of material activity.
II. Operational Process Control
1. Slowly introduce the heating medium while the paddle shaft is rotating, ensuring the warm-up period exceeds 30 minutes to avoid damaging the material due to sudden operational changes.
2. Precisely regulate the feed rate; avoid forced, high-volume feeding. Adjust the paddle shaft's variable-frequency rotation speed to maintain a material residence time of 10–60 minutes, tailoring the process to the specific dehydration needs of the heat-sensitive material.
3. During continuous operation, keep the main unit's current below 70% of the motor's rated value to prevent equipment overload and subsequent abnormal temperature fluctuations.
III. Shutdown and Post-Processing Control
1. Completely empty the material from the machine before shutdown; stop the steam supply and drain condensate from the cylinder. Allow the entire unit to cool to room temperature before stopping the paddle shaft rotation.
2. After drying, circulate cold water to cool the material simultaneously; this prevents high-temperature material from contacting the air, which could cause oxidation or degradation.
IV. Equipment Suitability and Protection
1. Prioritize the use of 316L medical-grade stainless steel for parts in contact with the material, and apply a mirror-polish finish to the inner walls to prevent material residue and bacterial growth.
2. For easily oxidized heat-sensitive materials, equip the system with a nitrogen purging device to fill the cylinder with inert gas, thereby excluding oxygen and preventing material discoloration or degradation.
3. Strictly prohibit the inclusion of hard foreign objects-such as metal fragments or stones-in the material to avoid equipment damage and operational anomalies.
