Yes in some sections when the equilibrium between the rising vapour and the liquid going down is not done it is a signal of dirty trays or damage sections.
A damaged tray means a loss of separation effectiveness (rectification or stripping capability). I can't think of a reason it would contribute to or cause flooding. Depending on the specific damage, it could also cause loss of separation efficiency for the tray below, if the liquid is spilling onto the lower tray without passing through the downcomer.
damaging just one part of tray of course cant lead to flooding. I mean, damaging at least in 3 consecutive trays leads to flooding. we faced a terrible flooding in amine regeneration column. this flooding caused to break all of trays in the column. I investigated all parameters that lead to flooding but the only logical and acceptable reason was damaging the 3 consecutive trays. cause the vapor go through the trays in broken part, when reach the intact tray,create a massive fog on tray and downcommer buck up occur.
In amine regenerater there is chance of Heat stable salts (HSS) formad and tray plugged with this.
it is more sensetive to pluging and chance of flooding
the severe form of flooding is Puking. puking can destroy trays intensively. in puking the bottom level of tower goes up and down for more than one time, in other word, in level graph versus time you have a wavy graph, a graph like nearly sin(x), I say nearly, not exact sin(x). plugging trays with scales or destroying more than 3 trays can cause to this phenomena, Puking. according my field investigation, loose bolt on tray, specially on center parts, leads to segregate this part of tray, and finally what happened that said in prior post.
I hope this experience be useful, and I really appreciate for your contribution. Any comments and ideas are welcomed.
To avoid loose bolts you can put spring washers. But trays blow ups most of the times are not caused by loose bolts, the blow ups are caused during start ups because of bad steam purging and water quick expansion acumulated in stagnant points of the column. Another cause for the damaged trays can be a leak in a reboiler exchanger in the bottom of the column, dirty on reflux trays can also lead to flooding of the column. Hope it helps.
