High Viscosity Thin Film Processors

The Large Volume Processor program consists of horizontally arranged, heated reactors with twin (co- or counterrotating) shaft which provide intensive mixing and kneading. The highly versatile large volume processors Reasil and Reacom are characterised by the following advantages: Very large volumes The highest viscosity melts (up to 15,000 Pas) and solids can be processed efficiently Low shear processing Long residence times are achieved economically Mixing, devolatilization, reaction and phase change (from melt to solid) can take place in the same machine. A successful devolatilization or reaction system consists of the right processor design integrated with properly engineered subsystems. SMS can provide a complete system, including installation and start-up services, or full engineering and design documentation to allow you to add the necessary subsystems for our high volume processors.

The Reactotherm is a heavy duty processor with an intensive mixing and kneading effect and self-cleaning ability. It is used for thermal processing of a wide variety of pasty, viscous, and fouling products. It can be operated continuously or batch-wise. The Reactotherm consists of a cylindrical, horizontal shell and a rotor with segmented discs and mixing bars. Stationary mixing hooks are attached to the inside of the shell. The close clearance between the mixing hooks, the segmented discs and the rotor result in a high mixing and kneading effect and the self-cleaning properties of the rotor. The inside of the shell is cleaned by the mixing bars. Fouling of heat exchange surfaces and the formation of agglomerates are avoided. The shell, the rotor shaft and the discs can be heated or cooled. The product transport is accomplished by the slightly pitched mixing bars.

For the thermal separation of a mixture a thin film is produced at the heated wall of a cylindrical or conical evaporator. A distribution ring on the rotor distributes the liquid evenly across the periphery. Then, the blades fitted at the rotor spread the liquid as a thin film of min. 0.5 mm over the heat transfer surface. The model concept for the flow in the thin film evaporator assumes that prior to each rotor blade a bow wave is formed. In the gap between the rotor blade and the heating surface, fluid is supplied from the bow wave of a highly turbulent area with intense heat and mass transport. This results in a good heat transfer performance even with viscous products. In addition, the formation of deposits is avoided and the intensive mixing also protects temperature-sensitive products from overheating.