A Natural Circulation Evaporator has components similar to that of a forced circulation evaporator except the circulation pump. In this case, the flow is natural due to density difference or thermosyphon. The tubes within the calandria are very short, about one to two metres in height.
The liquid in the calandria is heated, which decreases the density of the liquid. This pushes the liquid with reduced density to rise above and flow into the separator at the top and travel down through the central down-comer. The volume is reduced to desired level as per the concentration required.
