Hi

We have a 18m3 7bar/full vac rated vessel that has a spring PRV of set pressure 125 psi and 175 l/min rated discharge.

What I need advice on is calculating required discharge rate i.e. is our PRV correct.

Material is introduced into the vessel via vacuum.

The main problem comes from the two streams we have, one is vac'ed material that is ambient temperature from small drums.

the other is vac'ed at ~150 deg c in one go in volumes of approx 3,000L.

I guess worst case would be vessel nearly full i.e 15m3 of "cold" ambient material, then 3m3 of 150 deg c material is vac'ed in, and then cools. Will this over pressure the vessel? And what will be the rate of discharge be? / is it less than the 175 l/min of the current PRV?

I need to check who the pressure will alter as the material cools and can the PRV cope?

There are quite a lot of information required to define the problem correctly...

Let take A is "ambient material" and B is "150 deg c material"

i) is there any reaction between A & B ? Exothermic or endothermic ? Vapor generation ? A+B form C. Is total volume expand or contract ?
ii) if no reaction, is A mix with B in the drum ? is the process of mixing create or absorb heat ?...
iii) is stirring occur ? Is foam potential form ?

I guess you really need all these to be answered so that to view what the real relief scenario. Without knowing all these fundamental information, it would be difficult for you to define correctly...

15 m3 of "cold" ambient material, then 3 m3 of 150 deg c material is vac'ed in to a 18 m3 drum...theoretically you have check what the total effect (contraction of B and expansion of A) of this mixing...

Sorry for NO constructive comment here...