500-Word Description of a 5㎡ Vacuum Freeze Dryer Machine A 5㎡ vacuum freeze dryer (lyophilizer) is a specialized industrial or laboratory-scale equipment designed to preserve heat-sensitive materials by removing moisture through sublimation under vacuum conditions. This process, known as lyophilization, ensures the structural integrity, biological activity, and shelf life of products such as pharmaceuticals, food, biological samples, and chemicals. Key Components and Working Principle 1. Drying Chamber (5㎡ Shelf Area): The primary compartment accommodates trays or shelves with a total effective area of 5 square meters, suitable for medium-scale production. It houses the product during freeze-drying and maintains controlled temperature and pressure. 2. Condenser (Cold Trap): A low-temperature condenser captures moisture sublimated from the product, typically operating at -50°C to -80°C. It prevents water vapor from contaminating the vacuum pump. 3. Vacuum System: A robust vacuum pump reduces pressure inside the chamber to 0.1–0.01 mBar, enabling ice to transition directly from solid to vapor (sublimation) without melting. 4. Refrigeration System: Compressors or cascade refrigeration units maintain ultra-low temperatures in the condenser and shelves, ensuring efficient moisture removal. 5. Control System: An automated PLC or touchscreen interface monitors and adjusts parameters like temperature, pressure, and drying time. Data logging ensures process traceability for compliance with GMP or ISO standards. Freeze-Drying Process 1. Pre-freezing: Products are frozen to -40°C or below to solidify water content into ice crystals. 2. Primary Drying (Sublimation): Under vacuum, the chamber temperature is gradually raised, allowing ice to sublimate. This phase removes ~95% of moisture and may take hours to days, depending on product thickness. 3. Secondary Drying (Desorption): Residual bound water is removed by slightly increasing shelf temperatures (up to +30°C) while maintaining low pressure, ensuring final moisture levels below 1–2%. Applications - Pharmaceuticals: Lyophilized vaccines, antibiotics, and protein-based drugs. - Food Industry: Preserving fruits, coffee, and ready-to-eat meals without nutrient loss. - Biotechnology: Stabilizing enzymes, cells, and diagnostic reagents. - Research: Long-term storage of sensitive laboratory samples. Advantages - Quality Retention: Avoids thermal degradation; porous structure aids rehydration. - Extended Shelf Life: Moisture removal inhibits microbial growth. - Efficiency: Modular designs allow scalability for pilot or production needs. Technical Specifications (Typical) - Shelf Temperature Range: -55°C to +70°C - Ultimate Vacuum: ≤0.01 mBar - Refrigeration: Air-cooled or water-cooled - Material: Stainless steel (SS304/316) for corrosion resistance Conclusion A 5㎡ vacuum freeze dryer balances capacity and precision, making it ideal for industries requiring medium-batch lyophilization. Its advanced control systems, energy-efficient refrigeration, and compliance with hygiene standards ensure reliable performance for critical applications. (Word count: 500)