PSV for fluid containing solids

[drsugar]

Hi everybody,

In order to protect our vessels we have to install a safety relief valve besides a pressure controlled on/off-valve. The fluid (about 40 gpm@ 60 psi) contains about 30% of solids (size 150 to 400 microns) and is pumped with a positive displacement pump.
I contacted a dozens of manufactures but the problem is always that the solids prevent the valve to close properly if it opens once.

To my knowledge PSV's are also used in the mining and oil industry where solids are an issue but I didn't find any suitable information during my internet search.

Perhaps anyone in this forum has an idea?
Thanks in advance.

Drsugar

 

[JoeWong88]

Rupture disc is one of the good overpressure protection for fluid with solid.

Consider to provide Rupture disc (RD) upstream of PSV will avoid fluid contains substances possibly precipitate / polymerize / crystallize / solidify accumulate at the inlet nozzle and pipes. (Read more in "Why Rupture (RD) Upstream of Pressure Relief Valve (PRV) ?"). In the event RD is provided upstream of PSV, consider to install device to identify the potential of RD.

JoeWong
Chemical & Process Technology

 

[drsugar]

Thank you Joe for your reply. To provide a rupture disc is an idea we will discuss.

I should have mentioned that the fluid is water containing ion exchange resin. Therefore we don't have the problem of crystallization or precipitation at the valve inlet during normal operation. The only problem is that the resin is trapped between the disc and the seat when the valve closes and leakage could be possible.

Klaus

 

[gerhardl]

To ecco JoWong88 : a rupture disc is still the obvious solution. The art is to select a rupture disc type with small enough tolerance and a set pressure to avoid disturbance and damage/leakage to the disc during normal process operation, with normal pressure peaks.

If you set up the bursting disc in addition with a leakage detection system (bursting /leaking indicators exists), and your system has sufficient pressure tolerance between operationol normal pressure and relief pressure, I do not see why you should need a PSV in addition.

 

[JoeWong88]

drsugar,
It is great that you will consider RD...

Well... resin is trapped between the disc and the seat lead to continuous passing is a know and nasty issue.

gerhardl,
Sometime RD could failure on fatigue or surge. Provision of second RD or PSV could be a measure to minimize opportunity of system shutdown...

JoeWong
Chemical & Process Technology