Industrial Wiped Film Evaporator for High-Boiling Silicone Oils, Polymer Plasticizers & Specialty Chemical Separation

Designed for heavy-duty industrial processing, this robust stainless steel Wiped Film Evaporator excels at continuously separating high-boiling, viscous, and heat-sensitive chemicals that are beyond the capability of conventional fractionating columns. From silicone oil devolatilization and plasticizer purification to polymer intermediate recovery, the system provides a true continuous process with an unparalleled ability to handle viscosities up to tens of thousands of centipoise. Its modular, jacketed design and specialized high-torque drives ensure reliable, 24/7 operation while stripping unreacted monomers, catalyst residues, and volatile offcuts down to ppm levels, creating ultra-high-purity specialty chemical products that consistently meet high-performance material specifications.

Process engineers face a formidable barrier when distilling materials like high-viscosity silicone fluids, epoxy resins, or molten polymers. Traditional packed or tray columns immediately foul with gelling or polymerizing material, causing catastrophic pressure drop and shutdowns. In a simple batch pot still, the stagnant liquid pool exhibits terrible heat transfer and an extremely low surface-to-volume ratio. Extended heating required for product to boil from the pool drives unwanted side reactions, discoloration, and molecular weight changes in the product. The high boiling points of plasticizers or functional oils mean they require exceptionally high heater temperatures, yet exposure to this heat in a bulk pool for hours inevitably degrades product quality, making it impossible to meet demanding ASTM or ISO specifications for color and purity.

Our Industrial WFD system solves these mass and heat transfer limitations by mechanically generating a high-velocity, turbulent thin film. The high-torque, precision-balanced rotor is equipped with rigid, close-clearance wipers that forcibly spread even the most viscous fluids into a film of a few tenths of a millimeter. Under exactly controlled vacuum (down to 0.01 mbar), the effective boiling point is dramatically suppressed, allowing low-vapor-pressure plasticizers or silicone cyclics to be stripped out without overheating the main polymer chain. Volatiles evaporate in seconds and are condensed, while the purified base polymer steadily exits through a heated, positive-displacement residue discharge pump. This eliminates stagnation, enables continuous operation without fouling, and achieves residual volatiles in the low ppm range, recovering value from both the heavy product stream and light fractions.

• Silicone & Siloxanes: Stripping volatile cyclics (D4, D5, D6) from high-viscosity silicone oils.
• Plasticizers: Final purification of phthalate-free plasticizers to achieve ultra-low color and odor.
• Lubricants: Devolarization of synthetic esters and PAO for high-temperature lubricant formulations.
• Polymers & Resins: Monomer stripping from epoxy resins, acrylic prepolymers, and biodegradable polyesters.

Viscous feed is pumped into the unit’s top chamber, where it flows onto a slowly rotating distribution ring. This evenly feeds the liquid onto the heated wall as mechanical wipers instantly generate a film just fractions of a millimeter thick. The massive surface renewal and high turbulence coefficient drive volatile materials (monomers, light ends) to the vapor-liquid interface. The vapors traverse a short path to the central condenser, while the purified heavy fraction is scraped down the body and discharged from a heated conical bottom. All operations are continuously monitored and automated via a central PLC.

Specification begins with your product’s thermal stability graph and viscosity curve. Request a pilot test with a 0.5m² unit to define the exact pressure/temperature/feed rate matrix. This provides the critical scale-up data: evaporation rate (kg/m²/hr) and residual volatiles. The wiper type is the critical engineering choice; zero-clearance, fixed-blade wipers maximize film turbulence for ultra-high-viscosity stripping. Ensure the vendor specifies the residue handling system carefully—a heated, conical bottom and jacketed residue pump are non-negotiable for high-melt-point polymers to prevent a "cold plug" that would halt production. Magnetic drives offer a premium zero-leakage option for toxic or valuable chemistries.

1. Q: What is the maximum viscosity you can effectively evaporate?
   A: We have successful field applications processing fluids exceeding 50,000 cP. The mechanical action of the rotor provides forced convection, unlike gravity-dependent falling film equipment. Performance data for your specific high-viscosity fluid is easily obtained via pilot testing.
2. Q: Can this remove color bodies and oligomers from my plasticizer product?
   A: Yes. Our Wiped Film systems are the industry workhorse for final plasticizer "polishing." By providing a very short, controlled heat history, we distill the high-boiling plasticizer and leave dark, sticky polymers and color-formers in the residue stream, giving you a water-white, market-grade final product.
3. Q: What happens if my product solidifies at room temperature?
   A: The processing system is designed for hot melt operation. All feed lines, the evaporator body, the residue discharge systems, and the collection vessels are fully jacketed and remain heated throughout the process to prevent any solidification or gelling.
4. Q: How do you guarantee zero cross-contamination between custom synthesis campaigns?
   A: The thoroughly scraped wall and low hold-up volume facilitate easy cleaning. The system is designed for complete CIP integration. Between differing chemistries, a single-solvent flush and thermal cleaning cycle is typically sufficient to remove all detectable traces.
5. Q: Is a single pass always sufficient to meet my specification?
   A: For high-value silicone stripping, one pass is usually sufficient. For demanding monomer removal to ppm levels, we sometimes recommend a two-stage stripping setup. We can predict this with high accuracy from a single pilot run, providing you a definitive guarantee on achievable levels.