What are the reasons for no liquid level at the bottom of the distillation tower? How to handle it?

Reasons: 1. Low feed volume, 2. High steam volume, 3. High recovery rate of pure methanol, 4. Large amount of residual liquid discharged, 5. Faulty level gauge

Reason: Low reflux ratio, high recovery rate, high bottom temperature, large amount of material discharged from the bottom of the tower, low processing capacity of the pressurized tower, and low water content in crude methanol. Solution: Increase the reflux ratio (increasing the reflux ratio will correspondingly reduce the recovery rate; it is necessary to maintain the level in the reflux tank and the top temperature of the tower, without disrupting the operation of the tower)； Reduce the bottom temperature of the tower (for three towers, it is possible to appropriately lower the top temperature of the pressure tower in order to make adjustments, but this must not disrupt the operation of the pressure tower) ； Reduce emissions at the bottom of the tower; if the liquid level is too low, emissions can be stopped, and they should be resumed once the level rises to 800–900 ； Increasing the temperature of the pressure column raises its load; as a result, the alcohol content in the bottom of the pressure column decreases while the water content increases, leading to an increase in the amount of water in the atmospheric pressure column. The above are my personal opinions; please point out any mistakes if there are any

If it is a packed tower, the reason might be that the packing inside the tower is blocked (especially in the section where the feed liquid enters). As a result, as the heating steam rises, the flow rate of the feed liquid slows down due to the blockage caused by the packing. This leads to a condition of vacuum formation at the bottom of the tower and in the reboiler section, causing the temperature inside the tower to rise significantly and rapidly. Under certain feeding conditions, this can result in the tower being flooded”