1
Q
Evaporators may be divided into what three types
A
- natural circulation units
- forced circulation units
- film type units
2
Q
Describe horizontal tube evaporators
A
The horizontal tubes extend between two tube plates to which they are fastened, either by packing plates, or expansion. Above the heating section is a cylindrical portion in which the separation of the vapour from the liquid takes place. The vapour leaves through some form of de-entertaining device
3
Q
Describe the vertical tube evaporator
A
A vertical cylindrical body is used, with the tubes held between two horizontal tube plates which extend right across the body
4
Q
What are some of the problems that arise during evaporation
A
- high product viscosity
- heat sensitivity
- scale formation and deposition
