Tower flooding reduction

Flooding is an excessive accumulation of liquid inside a column. Flood symptoms include a rapid rise in pressure drop (the accumulating liquid increases the liquid head on the trays), liquid carryover from the column top, reduction in bottom flow rate (the accumulating liquid does not reach the tower bottom), and instability (accumulation is non-steady-state). This liquid accumulation is generally induced by one of the following mechanisms. 

Figure 9.3 Reduction of seal pan to downcomer clearance can flood tower.

Flooding In distillation, the point in the operation where increases in vapor-liquid loading cause a noticeable reduction in the fractionation efficiency or tray efficiency of the tower. 

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