The engineering task
A wet product must be dried gently under vacuum. During heat-up, mass, heat capacity, transfer and evaporation rate change, making the process strongly transient.
Atmospheric pressure acts outside while the vessel is under vacuum. The heating jacket, agitator and repeated batches create additional pressure, temperature and mechanical cycles. Shell stability rather than internal pressure alone governs design.
Required design data
- Batch mass and initial/final moisture
- Solvent/water vapour pressure and vacuum level
- Heating utility and heated area
- Agitator duty, geometry and number of cycles
Technical solution approach
Separate drying periods
Balance heat-up, constant-rate evaporation and falling-rate drying separately.
Couple heat and mass transfer
Available heat limits evaporation; product state and vacuum determine boiling temperature.
Size the vapour system
Maximum vapour rate defines piping, condenser and vacuum system.
Check vacuum stability
Verify shell, heads and stiffening rings for full vacuum at adverse temperature.
Assess cycles
Check pressure, temperature and agitator load cycles for the expected batch count.
Expected deliverables
Suitable SOL ALPHA modules
The modules form a technically plausible toolchain. Their final selection and sequence will be confirmed during the later calculation against the applicable code and project conditions.