PRV Design issue as process getting crystallization.(solid) 1

[Mussha]

In our storage Terphenyl Product tank, we are facing issues with Emergency Vent cover & Breather valve.

The Emergency vent cover pops up within 100 mmWC while its set pressure is 150 mmWC and process crystalizes & cause continues passing.

While Breather valves is not even passing and popping up. During overhauling, we observed the process crystallization.

To prevent the crystallization of process in the valve seats during operation, we provided electrical heat tracing cable over the valve bodies. But not effective.

Anu suggestion for suitable Breather valve and Emergency Vent cover for our process material Terphenyl with Melting point 200-220 DegC.

 

[Mussha]

@LittleInch, Thanks for the reply.
@gergevergese, Thanks for the high temp. cable spec. i will forward to our Electrical Engg. to study it for the PVRV application.

 

[Mussha]

@gergevergese, This cable might only give heating to the body of the PVRV, but crystallization happening inside also on diaphragm/disc, will discuss with our Electrical Engg.

 

[pierreick]

Mussha,
Latexman and I explained to you the issues with your process description, and you seem not understand that crystallization will occur as soon as the temperature of the product is below the freezing point i.e 212- 214 degrees C.
Flaws in your process are numerous (steam temperature, electrical tracing set point and capability and probably cold N2). All concurring to cool your product. What about sublimation? Is it possible with your product? This is one way to purify the product.
What is your role in your organization? refer to knowledgeable people, chemical engineer and/or safety engineer/manager.
This is definitely out of your sphere of competence.
You still asking the same question without understanding the physics.
I don't want to be rude.
Cheers
Pierre

 

[Mussha]

@Pierri, Thanks for your explanation. i am taking it in positive way always i am in learning mode. i will go in deep to understand points you mentioned. Appreciated your guidance.