Natural gas

[I2P]

friends,
I am working in a natural gas processing plant. We have observed that the filters on our compressor seal gas lines when opened reveal a fine black carbon like powder deposit.Also our flare burns with a sooty flame.I would like to know whether this is expected in natural gas.To share with you, our gas is 96%CH4, and the only higher ends are hexane,cyclo hexane,n-heptane.As such the gas composition is essentially comprised of aliphatics.So what is the source and explanation of such carbon like dust?
thanks to all

 

[jay165]

I would get a full anylysis of the inlet gas including tests for H2S, caronyl sulfide and mercury. Also take samples of the soot and have that analyzed too. If it's iron sulfide or an aluminum compound, you could have a serious corrosion problem. No, it's not normal, either.

 

[zqew05]

This may sound stupid, but is there soot on the downstream side of the filter? If it is, kiss your dry gas seal cartridge goodbye. Also, crack open your seal gas filter vent to flare (if rules allow it) at the most convenient flange connection and check for dark powder.