However, because the liquid film is not easily distributed uniformly in the tube, and the heat transfer coefficient is smaller than that of the rising film evaporator, it is still not suitable for materials that are easy to crystallize or scale.
Since the solution flows in the form of a film in the single-pass evaporator, the convective heat transfer coefficient is greatly improved, so that the solution can reach the required concentration after one pass in the heating chamber and no longer circulates. Therefore, it has a greater concentration than the circulating evaporator. advantage.
