Heating Unit Description (For Freeze-Drying System)

Function:

The heating unit supplies precise thermal energy to the shelves inside the freeze-dryer chamber to facilitate controlled sublimation of frozen material (primary drying) and the removal of residual moisture (secondary drying), ensuring consistent and uniform product drying.

Technical Specifications

• Heating Method:

  • Circulating thermal fluid (hot water or silicone oil) through internal shelf channels

  • Optional: Electric resistance heating or steam-based systems for specific industrial configurations

• Temperature Range:

  • +20°C to +130°C, programmable via system control

  • Tight tolerance: ±1°C shelf surface accuracy

• Heat Transfer Medium:

  • Silicone oil or synthetic thermal fluid, closed-loop and pressurized to prevent vaporization at high temps

  • Heated using external thermal oil unit (TOU) with stainless steel heat exchanger

• Flow Control System:

  • Variable-speed circulation pump

  • Proportional-integral-derivative (PID) controller ensures ramped heating without overshoot

  • Multizone control for independent heating of shelf groups, enabling flexible drying profiles

• Construction Material:

  • All heating contact surfaces made from stainless steel 316L for hygienic compliance

  • Seamless welding, electropolished channels to prevent fouling

• Integration with Freeze-Dryer:

  • Heating tubes connected to shelf manifolds inside the chamber

  • Fully integrated with SCADA or HMI control panel for recipe-based operation

• Safety Features:

  • Overheat protection and pressure relief valves on the thermal loop

  • Leak sensors, emergency shutoff valves, and redundant temperature sensors

• Energy Efficiency Options:

  • Heat recovery system to reuse thermal energy from condenser or vacuum pump loop

  • Standby and idle modes for non-drying periods

• Maintenance Access:

  • Easy access panels for fluid refill, filter change, and pump servicing

  • Inline diagnostics for temperature differential, flow rate, and fluid degradation

Optional Configurations

• Steam-heated version for facilities with existing boiler infrastructure

• Dual-mode heating/cooling unit for rapid switch from freezing to drying (if system doesn't use separate cooling plates)