Vacuum Evaporator
Vacuum Evaporator
Mechotech engineers and manufactures the Vacuum Evaporator as a general-purpose, jacketed batch or semi-continuous evaporator that operates under reduced pressure so the feed boils and concentrates at a lower temperature than it would at atmospheric conditions. It is Mechotech's simpler, all-round evaporation platform — a single agitated, vacuum-rated vessel rather than a dedicated film, forced-circulation, multi-effect, or mechanically wiped system — suited to general concentration, low-temperature drying, and small-to-mid batch duty where a specialized evaporator geometry is not required.
The feed is charged to a jacketed, agitated vessel; a vacuum system draws the vessel down to the target operating pressure so the liquid boils at a correspondingly reduced temperature, and the jacket supplies gentle heat through steam, hot water, or thermic fluid while the agitator keeps the batch mixed and prevents localized overheating at the vessel wall. Vapour generated is drawn off to a condenser where it is recovered as clean condensate, and the batch is held under vacuum and agitation until the target concentration, moisture content, or solids level is reached. Because it is a straightforward batch vessel rather than a continuous film or forced-circulation body, the Vacuum Evaporator is well suited to smaller volumes, multi-product changeover, and applications where flexibility and simplicity matter more than the steam economy of a multi-effect or MVR system; where continuous, high-throughput, or fouling-resistant duty is needed, Mechotech's dedicated film, forced-circulation, and multi-effect evaporators are the better fit. Mechotech builds the vessel, jacket, agitator, and vacuum system in SS 316L (or a process-appropriate grade) with electropolished product-contact surfaces, CIP connections, and PLC-based instrumentation, with vessel volume and vacuum rating configured to the specified batch size and product.
Process Flow
Technical Specifications
| Evaporator Type | Vacuum Evaporator, general-purpose agitated vessel |
|---|---|
| Working Principle | Reduced vessel pressure lowers the boiling point so the batch concentrates at low temperature under gentle jacketed heating |
| Vessel Type | Jacketed, agitated batch or semi-continuous vessel |
| Agitation | Motor-driven agitator, type and speed configured to product viscosity |
| Heating Medium | Steam, hot water, or thermic fluid in the jacket (configurable) |
| Operating Mode | Vacuum operation for low-temperature concentration of heat-sensitive product |
| Suited Duty | General batch concentration; smaller volumes and flexible multi-product changeover |
| Product-contact Material | SS 316L (or process-appropriate grade), electropolished |
| Condensing System | Surface or barometric condenser with vacuum ejector/pump |
| Automation | PLC-based control of temperature, vacuum, and batch endpoint (configurable to SCADA) |
| Cleaning | CIP-capable product-contact circuit |
| Batch Flexibility | Suited to multi-product changeover and varying batch sizes |
| Capacity | Configured to requirement — pilot to mid-scale batch evaporation duty |
| Utilities | Steam / hot water / thermic fluid for jacket heating, cooling water, vacuum system utilities, electric power, compressed air |
| Compliance | GMP/WHO-GMP hygienic design; documentation for regulatory qualification |
Plant Capacities
| Scale | Typical Batch Size | Vessel Configuration | Typical Duty |
|---|---|---|---|
| Pilot / R&D | Small batch | Single jacketed agitated vessel | Formulation and process development |
| Small commercial | Mid-size batch | Sized jacketed vessel with agitator | General batch concentration, flexible product mix |
| Mid-scale commercial | Larger batch or semi-continuous | Larger jacketed vessel, upgraded vacuum system | Higher-volume general-purpose evaporation |
Vessel volume, agitator duty, and vacuum system are engineered to the specified batch size, product viscosity, and heat sensitivity; for continuous, high-throughput, or fouling-resistant duty a dedicated film, forced-circulation, or multi-effect evaporator is usually the better fit.
Manufacturing Process
Batch Charging
Feed is charged into the jacketed, agitated vacuum vessel, either as a full batch or in stages for semi-continuous operation.
Vacuum Drawdown
The vacuum system draws the vessel down to the target operating pressure, lowering the liquid's boiling point ahead of heating.
Jacketed Heating & Agitation
Steam, hot water, or thermic fluid circulates through the jacket while the agitator keeps the batch in motion, distributing heat evenly and preventing localized overheating at the vessel wall.
Controlled Boiling & Evaporation
The batch boils gently at the reduced-pressure temperature, evaporating solvent or water while agitation maintains uniform concentration throughout the vessel.
Vapour Extraction & Condensation
Vapour is continuously drawn off to a condenser, where it is condensed and collected as clean condensate for reuse or disposal.
Endpoint Monitoring
Density, refractometer, or temperature-rise instrumentation tracks the batch toward its target concentration, moisture content, or solids level.
Batch Discharge
On reaching the endpoint, the concentrated batch is discharged from the vessel through a bottom valve to storage or the next process step.
CIP & Changeover
The vessel, jacket, and agitator are cleaned in place between batches or product changeovers, supporting flexible, multi-product operation.
Major Plant Equipment
- Jacketed agitated evaporator vessel
- Agitator drive motor and gearbox
- Steam/hot-water/thermic-fluid jacket heating supply
- Vapour outlet and demister
- Surface or barometric condenser
- Vacuum system (steam ejector or liquid-ring pump)
- Condensate receiver and pump-out
- Batch discharge valve and pump
- Density/refractometer and temperature instrumentation
- CIP skid and spray-ball connections
- Instrumentation: temperature, pressure/vacuum transmitters
- PLC-based control panel with MCC
Plant Output
Applications
- General batch concentration of pharmaceutical and nutraceutical liquids
- Low-temperature drying and pre-concentration of heat-sensitive extracts
- Small-to-mid batch food and flavour concentrate production
- Multi-product contract manufacturing with frequent changeover
- R&D and pilot-scale concentration trials ahead of scale-up
- Solvent recovery from small-volume process residues
- Botanical extract pre-concentration ahead of drying or crystallization
- General vacuum drying/thickening of viscous formulations
Key Features
Simple, Flexible Batch Operation
A single agitated, vacuum-rated vessel handles varied batch sizes and frequent product changeover without the fixed geometry constraints of a dedicated film or forced-circulation system.
Low-Temperature Processing
Operation under vacuum lowers the boiling point so heat-sensitive liquids concentrate gently, without the thermal stress of atmospheric boiling.
Uniform Heating via Agitation
The agitator continuously mixes the batch against the jacketed wall, preventing localized overheating and giving consistent concentration throughout the vessel.
Straightforward Cleaning & Changeover
CIP-capable construction and a simple single-vessel design make multi-product changeover fast and reliable for contract and multi-grade manufacturing.
GMP-Compliant Construction
Electropolished SS 316L product-contact surfaces with CIP connections meet WHO-GMP and Schedule M requirements for regulated-industry production.
Right-Sized for Smaller & Pilot Duty
Well matched to smaller batch volumes and R&D/pilot programs, with a clear upgrade path to Mechotech's dedicated film, forced-circulation, or multi-effect evaporators as volumes grow.
Frequently Asked Questions
What is a Vacuum Evaporator and how does it work?
How is a Vacuum Evaporator different from Mechotech's other evaporator types?
What kind of products suit a Vacuum Evaporator?
Can a Vacuum Evaporator be used for pilot trials before scaling up?
How is heat-sensitive product protected during vacuum evaporation?
What capacity range can Mechotech supply?
Does Mechotech supply the complete Vacuum Evaporator as a turnkey system?
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