Short Path Evaporator

Short-Path / Molecular Evaporator is a kind of thin film evaporation equipment operating under ultra-high vacuum (0.001 mbar level), which is specially designed for the mild separation of high-boiling point, heat-sensitive, oxidization-prone or high value-added materials. It combines thin film evaporator and condenser in a single apparatus. The vapors are condensed on the built-in condenser. The product path between the evaporation and condensation is extremely short, therefore, the pressure drop is low.

 1. Product Positioning

2. Core Structure

A. Heating cylinder: electric or thermal oil jacket, maximum temperature 350-400 ℃.

B. Built-in condenser: spiral coil or tube type, condensing area ≥ evaporation area, to realize “zero distance condensation”, to avoid secondary reaction.

C. Scraping Film System: centrifugal + mechanical double film: first centrifugal film dumping, and then mechanical scraping film, to ensure that the high viscosity (≤ 20 000 mPa-s) material uniform film.

D. Material: 316L / Hastelloy / Borosilicate glass 3.3 (laboratory visual model).

E. Vacuum System: two-stage oil diffusion pump + cold trap, ultimate vacuum 0.001 mbar.

F. Discharge system: Continuous lights / heavies’ dual collection, optional Carrousel multi-position tube switching, supports 24 h non-stop operation.

3. Key Performance

4. Typical Application

- Food: concentration of fish oil EPA/DHA, de 3-MCPD/GE, purification of monoglycerides.

- Pharmaceuticals: high boiling API, vitamin E, lanolin alcohol, isocyanate TDI/MDI purification.

- Polymers: polyethylene wax, silicone oil de-volatilization, lactic acid monomer recovery.

- Environmental protection: separation of waste lubricating oil and mineral oil residues.

5. Selection and Trial recommendations

• Small trial: glass visible model (0.04-0.5 m²), optimization of process parameters.

• Pilot: Stainless steel 2-10 m², verification of vacuum, temperature, film scraping speed.

• Industrialization: modular 20-80 m² with integrated DCS, CIP/SIP, explosion proof design.