General Specifications
| Parameter | Specification |
|---|
| Model Series | SRS-FFE Series |
| Evaporation Capacity | 50 – 50,000 kg/h water evaporation |
| Number of Effects | 1 to 6 effects (Multi-Effect) |
| Tube Material | AISI 304 / 316L / Duplex Stainless Steel |
| Tube Diameter | 25 – 50 mm |
| Tube Length | 6 – 12 m |
| Heating Surface Area | 10 – 4,000 m² |
| Operating Temperature | 40 – 85°C (product side) |
| Operating Pressure | Full vacuum to 0.5 bar(g) |
| Design Pressure (Steam Side) | Up to 6 bar(g) |
Available Options & Features
| Feature | Description |
|---|
| MVR / TVR | Mechanical or Thermal Vapor Recompression for high energy efficiency |
| CIP / SIP System | Clean-in-Place & Sterilize-in-Place capability |
| Automation Level | PLC + HMI with full SCADA integration |
| Material of Construction | 316L, 904L, Duplex, Titanium (on request) |
| Surface Finish | Ra ≤ 0.8 μm (food/pharma grade) |
| Skid-Mounted / Modular Design | Available for smaller capacities |
Note: Specifications shown are typical. SRS custom designs each Falling Film Evaporator according to the customer’s exact product, capacity, and site requirements. Detailed technical data sheets are available upon request.
Falling Film Evaporators are among the most widely used evaporators in the food, dairy, pharmaceutical, and chemical industries due to their gentle handling of heat-sensitive products.
✅ Advantages
| Advantage | Benefit |
|---|
| Very short residence time | 5–30 seconds — ideal for heat-sensitive products |
| Low operating temperature | Gentle evaporation under vacuum |
| High heat transfer coefficient | 1,500–4,000 W/m²·K |
| Low pressure drop | Energy efficient |
| Excellent for viscous liquids | Up to moderate viscosities |
| High concentration ratios | Single or multi-effect possible |
⚠️ Disadvantages
| Limitation | Impact |
|---|
| Sensitive to feed distribution | Requires high-quality liquid distributor |
| Not suitable for very high viscosity | Above ~200–300 mPa·s |
| Higher initial capital cost | Compared to simpler evaporators |
| Risk of dry spots / fouling | If flow is not uniform |
| Requires good vacuum system | For low-temperature operation |
| Limited to non-crystallizing products | May need other types for crystallizing solutions |
Summary: Falling Film Evaporators offer excellent thermal efficiency and product quality for most heat-sensitive applications. Their limitations are generally manageable with proper design and operation. SRS systems are optimized to maximize advantages while minimizing drawbacks.
Main Components
| Component | Description | Function |
|---|
| Liquid Distributor | Precision orifices or ferrules at the top of each tube | Ensures uniform thin film distribution across all tubes |
| Tube Bundle (Calandria) | Vertical stainless steel tubes inside a steam jacket/shell | Where heat transfer occurs — liquid film evaporates inside tubes |
| Vapor-Liquid Separator | Cyclone or baffle-type separator at the bottom | Separates concentrated liquid from vapor |
| Steam Chest / Heating Jacket | Outer shell surrounding the tube bundle | Contains heating steam or thermal fluid |
| Concentrate Outlet | Bottom discharge with level control | Removes concentrated product |
| Vapor Outlet | Top vapor discharge to condenser or next effect | Carries evaporated solvent (usually water) away |
Supporting Systems & Accessories
| Component | Purpose |
|---|
| Vacuum System | Lowers boiling point for gentle evaporation |
| Circulation / Feed Pump | Delivers feed to distributor |
| Condenser (Surface or Barometric) | Condenses vapor for reuse or discharge |
| Control Panel & Instrumentation | Temperature, pressure, flow, and level control |
| Support Structure & Platform | Structural frame with access platforms (for large systems) |
Note: SRS Falling Film Evaporators feature high-quality stainless steel construction, precision liquid distributors, and optimized tube designs for maximum efficiency and product quality. Systems can be configured as single-effect or multi-effect with TVR/MVR for superior energy efficiency.
Operating Parameters
| Parameter | Typical Range | Notes |
|---|
| Evaporation Temperature | 40–70°C | Lower under vacuum |
| Heating Steam Temperature | 60–120°C | ΔT of 3–10°C |
| Operating Pressure (Product Side) | 5–30 kPa (abs) | Vacuum operation |
| Feed Viscosity | < 200 mPa·s | Low to medium viscosity |
| Concentration Ratio | 1.5–5× | Higher in multi-effect systems |
| Film Thickness | 0.1–1 mm | Thin turbulent film |
Multi-Effect System Parameters
| Effect / Stage | Temp (°C) | Pressure (kPa abs) | Typical ΔT (°C) |
|---|
| First Effect | 90–120 | 30–100 | 5–8 |
| Intermediate Effects | 70–90 | 10–40 | 4–6 |
| Final Effect | 40–60 | 5–20 | 3–5 |
Design & Performance Parameters
| Parameter | Typical Value / Range | Unit |
|---|
| Heat Transfer Area | 2.5 – 4,000+ m² | m² |
| Tube Length | 6–15 m | m |
| Overall Heat Transfer Coefficient | 1,500 – 3,500 | W/m²·K |
| Steam Economy (Multi-Effect) | 3–6+ | kg vapor / kg steam |
| Residence Time | 5–30 | seconds |
Note: Actual operating parameters vary depending on the product and number of effects. SRS Falling Film Evaporators are engineered for optimal performance within these ranges. Pilot testing is recommended for specific applications.
Typical performance characteristics of Falling Film Evaporators across various operating conditions and configurations.
Key Performance Metrics
Heat Transfer Coefficient: 1,500 – 4,000 W/m²·K
Evaporation Rate: 20 – 50 kg/h·m²
Steam Economy (Multi-Effect): 3 – 6+ kg/kg
Performance Comparison
| Parameter | Single Effect | Double Effect | Triple Effect | Typical SRS System |
|---|
| Heat Transfer Coefficient (W/m²·K) | 2,000 – 3,000 | 2,200 – 3,200 | 2,300 – 3,500 | 2,800 – 4,000 |
| Evaporation Capacity (kg/h·m²) | 25 – 40 | 28 – 45 | 30 – 48 | 35 – 50 |
| Steam Economy (kg vapor / kg steam) | 0.85 – 0.95 | 1.8 – 2.1 | 2.6 – 3.0 | 4.0 – 6.5+ |
| Residence Time (seconds) | 8 – 25 | 10 – 28 | 12 – 30 | 5 – 20 |
| Typical Operating Temperature (°C) | 50 – 70 | 45 – 65 | 40 – 60 | 40 – 65 |
Relative Performance Comparison
Heat Transfer EfficiencyExcellent
Energy EfficiencyVery High
Product Quality PreservationOutstanding
Note: Performance values shown are typical for SRS Falling Film Evaporators. Actual results depend on product properties, feed concentration, and system configuration. Multi-effect systems with Thermal Vapor Recompression (TVR) or Mechanical Vapor Recompression (MVR) significantly improve energy efficiency.
