Analyze the cause of failure of a falling film evaporator
The operation failure of falling film evaporator is because the low vacuum degree is too low to maintain the concentration boiling point and the temperature rise of the secondary steam, thus reducing the temperature difference between the heating steam and the concentrated solution, thus reducing the heat transfer and slowing down the speed of steam evaporation. In addition, the heating temperature of heating materials will affect the preservation of active ingredients. Due to the low vacuum, in addition to the influence of mass concentration, the production capacity of falling film evaporator is also reduced. The reasons for low vacuum are as follows:
1. Compress all parts of the equipment into the air. Air infiltration will increase the burden on vacuum equipment, and may even cause failure.
2. The cooling water is insufficient. In addition to pump equipment, the lack of cooling water is mainly due to pipe blockage, which will lead to valve damage. Excessive cooling water will prevent the secondary steam from condensing in time, thus seriously affecting the operation of vacuum equipment.
3. The cooling water temperature is too high. If the cooling water temperature is too high, a large amount of secondary steam generated by central heating will not be condensed in time. Therefore, the vacuum of the condensing equipment will soon be reduced.
4. The steam pressure is too high. If the heating steam pressure is too high, the evaporation rate of the falling film evaporator will increase rapidly. The generation of a large amount of secondary steam increases the load of cooling equipment and gradually reduces the vacuum degree. Reducing the vacuum degree will also increase the evaporation temperature of the material, affect the product quality, and ultimately reduce the production capacity of the equipment.
