Acceptable leak rate - CDU column

[Milutin]

Dear all

Does anybody have idea of acceptable leak rate for partial draw of tray?

Tray is for light gas oil and puparound drawing. Rate of LGO is about 80m3/h and 400m3/h for PA. Column is 6m diameter. Tray has two chimneys and two overflow weirs 1.5m high.

Regards

 

[0707]

In a draw off tray the drop in water level shall not exceed 25mm in 5 minutes.

 

[EmmanuelTop]

Does the previous statement apply for all mounted chimney/partial draw-off trays?

What should be the initial water level, before the leak test is going to start? The maximum one, 50% of max. level, or something else? Where can we find standardized procedure for tray leak testing?

 

[0707]

The usual leak test procedure for draw-off trays is as fallows:

Block drain holes with putty.
Fill with water (check water quality - maximum chlorides).
Mark water level (above 50%) and leave for 30 minutes; level shall not drop by more than 50 mm, unless otherwise specified.
Allow water to drain and check flow (slope of gutters/trough).
Remove all putty from drain holes.
Check cleanliness and arrange acceptance.