Freeze Protection of PSV Lines

[121202]

I am looking for some advice from Chemical Engineers with experience of installing Pressure Safety Valves in cold climates such as Western Canada or Alaska. I am reviewing the design of a process plant that will be located in a harsh environment subject to extreme low temperature (-20 deg C minimum) during the winter. Some of the vessels located on this plant have large (8"-12" NB typically) free draining PSV inlet and tail pipes. Currently these lines are bare and exposed and have not been insulated or heat traced on the basis that it is impossible for water to stand in them (the lines are gas filled and slopes are provided to enable draining of condensed water). I personally do not believe that freezing of these lines is credible. However, I am interested to here about any operational experiences or views from engineers working in similar cold climates.

 

[farshi]

hi
the condensate(water)should be drainage and the drain line should had electrical tracing for prevention of freezing in drain line.

yours,
farshi