Plugging of valve due to sulphur dust

[TingaTangaBob]

We encountered a problem recently in one of our metering station where the valve is plugged up. When the valve was disassembled, the sulphur dust have somehow collected on the drilled-hole cage. The gas stream is heated upstream and no plugging occurs in the piping until it reaches the valve.

Is anyone aware of this problem? is there some chemical phenomenon similar to hydrate formation that occurs with sulphur?

 

[hacksaw]

your question may have been dealt with before, search forum under gas pipe lines