How Rototherm® works
Shorter residence times reduce product degradation
Rototherm’s high-speed rotor creates centrifugal force, which keeps the feed against the heated cylinder wall. A turbulent thin film between the rotor blades and wall covers the entire heated surface at all times, independent of the feed or evaporation rates.
The turbulent thin or wiped film creates high heat transfer efficiency, minimizing the area required for evaporation. The film is continuously renewed by the incoming feed as the progressively more concentrated material moves towards the bottoms discharge nozzle. Product residence time in the Rototherm is generally measured in seconds, minimizing degradation of heat-sensitive materials.
Rototherm allows for up to 99% evaporation in a single pass and can concentrate dilute solutions to powder. Dry spots are eliminated because the process wall, unaffected by gravity, remains fully wetted at all evaporation rates.
When used as a continuous reactor, Rototherm’s multiple feed points and temperature zones, controlled residence time, and simultaneous evaporation of reaction by-products provide total flexibility for complex reactions. Rototherm’s short residence times allow reactions to be run at higher temperatures than conventional reactors, increasing the rate of reaction without compromising product quality and yield.