EO feed line with minimun distance branch line

[uu78hswang]

Dear Sir

There is EO(ethylene oxide) feeding from other plant
to EO surge drum (simple drawing attached in the file).
I was wonder why there is a small brach line on
the p&id, and it was written in the note that

EO should be to provide "minimum dead leg" and any branch line should provide a block valve with "minimum distance"

could you please kindly give me some idea behind this?

Thank you so much.

 

[Latexman]

EO is very reactive, so you don't want to create places where EO can accumulate, become stagnant, sit there for a relatively long time, and react. You want the EO flow to sweep all the molecules along to where you want them, not to where you don't want them.

Good luck,
Latexman