What causes steam to come out from inside the elbow box door?
Thread Content
There is no superheated steam in the vacuum furnace of our atmospheric and vacuum distillation unit, but during each inspection steam is always found escaping from the four feed lines of the vacuum furnace as well as from inside the elbow box doors (note: it’s not very clear in the photos). We have checked many places yet were unable to determine the root cause Has anyone encountered this?
Is there condensed water inside the box?
This should be the best explanation now, but it wasn’t there before
If we’re just talking about the inside and outside of the elbow box door, then the temperature difference will definitely be large…
There may be a slight pressure difference in the convection section here; if the seal of the elbow box is not tight, flue gas can leak outside. This issue may not be apparent when the ambient temperature is high, but when the temperature is low, water vapor in the flue gas condenses, resulting in moisture formation.
At the moment, we also think this is the most reasonable explanation, but there is dripping inside the insulation of our feed pipeline as well…
It seems that the insulation on the outside of the tube sheet in the elbow box of the convection section is adequate, but the gap through which the convection tubes pass through the tube sheet isn’t properly sealed. Additionally, the insulation around the door of the elbow box is not effective; this is probably due to the condensation of flue gas that leaks in from where the tubes pass through the tube sheet