Liquid sulphur Sampling leak issue

[syedpda77]

Dear friends,

We are facing a regular problem with existing Liquid sulphur sampling assembly in which there is a formation of solid sulphur in the sulphur sampling valve leading to its clogging. when the operator tries to open the sampling valve, no liquid sulphur is coming out & and when trying to close, valve is not getting fully closed due to solids in between valve seat area. Sampling valve is SS 316 & is needle type.
Sampling assembly has steam purge to remove the solidified sulphur but the assembly not working as the sampling needle valve is passing, the sulphur is clogging the steam purge valve also.

Kindly suggest possible measures to correct the problem the assembly design or suggest the specialist vendor who is supplying the sampling arrangements for liquid sulphur.
The vendor for the existing the sampling station is no more manufacturing and has closed the manufacturing & not supporting the queries.

 

[jari001]

Could you try using a diaphragm valve? I imagine the simpler profile of which valve parts are in line of the liquid should make the steam cleaning easier but I'm not sure what type of diaphragm material you would need.

 

[LittleInch]

A what temperature is all this at and how do you keep the sampling system hot enough?

Melting punt is 115C and most systems kept at 140.

What pressure is your steam supply?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[mk3223]

IMO, the heating steam system should be fixed and in service for the proper liquid sulfur piping system. The "piston" type of the sampling valve, such as Strahman, can be used in the liquid sulfur sampling.

https://www.strahmanvalves.com/prod...pling-valves/metal-seated-sampling-valves-en/

 

[Danlap]

Hi syedpda77,

Aside from fixing the heat tracing, suggest to do as follow:
- Add a block valve which located very close to the vessel/tank/or any means of compartment om which its product subject for sampling. This to minimize the dead / non flowing area in between the relatively hotter and bigger tank and the sampling valve. Thus also minimize the possibility of solidified slurry. Suggest to use block valve with small cavity e.g. ball valve or globe valve.
- Use the "real" sampling valve. Strahman as per mk3223 suggested or similar will do (as Strahman may not be readily available in some countries). Be cautious upon design selection. Some incorporate PTFE packing that may not be suitable for your application. And depending on the inlet orientation, it may be required to incorporate the "protruding" spindle/plug so that in close position it is always "wetted" and not clogged. Even shall clogged, it can be scrapped by means of opening it (during sampling).
- Correct protocol. When open do the sampling valve first and then block valve. And when closing, do the block valve first, let it drip until the last sulphur you can get and then close the sampling valve. Minimize the entrapped volume of sulphur until your next sampling.
Lower elevation of sampling valve in regards with the block valve may help.

Kind regards,
MR

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