The SMS Short Path Evaporator with internal condenser has been mastering demanding thermal separation duties for more than 60 years.
The unique combination of evaporation and condensation in extreme proximity permits the operation of the Short Path Evaporator with a vacuum up to 0.001 mbar (a). This operating range is unchallenged by any other type of evaporator.
Short Path Evaporator
The evaporator for extraordinary applications
Advantages
The benefits of SMS short path evaporators are obvious:
- Minimum pressure drop permits high vacuum operation and low product temperatures
- Gentle distillation of heat sensitive products with short residence times and minimum product hold-up in the evaporator
- The special design of the Short Path Evaporator enables Molecular Distillation
- Efficient droplet separation for outstanding distillate quality
Working principle of short path distillation
Basic Operating Principle
Short path distillation is a thermal separation technology operating at process pressures in the range of 1 to 0,001 mbar. It lowers the boiling temperature and is an excellent method for gentle thermal treatment of heat sensitive, high boiling products. The short path evaporator consist basically of a cylindrical body with a heating jacket, a rotor and an internal condenser.
The rotor creates a mechanically agitated, thin product film on the heating surface inside of the body. By means of gravity the product flows down in a spiral path, whereby the volatile portion of the product evaporates. The vapour passes by the shortest route and with practically no pressure drop to the internal condenser. The non-volatile portion reaches the lower part of the evaporator and is discharged through the bottom product outlet. The residual vapours and inert gases flow through the vacuum nozzle to the vacuum system.
Design Features of Short Path Evaporators
SMS Short Path Evaporators are available in a unique variety of rotor designs comprising:
- PTFE or Graphite wiper elements
- Spring loaded PTFE or wiper elements
- Metal wiper elements
- Polymer or Graphite rollers
- Hygienic design
The rotors can be equipped with specially designed splash guards, protecting the internal condenser from droplets in the vapour stream and ensuring highest distillate quality.
The internal condenser can be removed from the bottom of the short path evaporator. The majority of the short path evapoarators is supplied with tubular condenser, but SMS has designed special thermoplate condensers to meet the hygienic requirements of the food and pharma industry.
Typical Applications
The short path evaporator is specifically well suited for distillation, evaporation, concentration and stripping of heat sensitive products as follows:
- Stripping isocyanates from prepolymers
- Stripping of monomers from silicone oils, resins and polymers
- Evaporation of oil and wax fractions from petroleum
- Fractionating of waxes into hard and super hard waxes
- Stripping solvents and dimers form all kind of resins
- Distillation of monoglycerides from di- and triglycerides
- Concentration of Omega-3 fatty acids
- Evaporation of methylester
- Concentration of vitamin E, (tocotrienol & tocopherol)
