Black oily dirt in natural gas lines

[gustorf]

We recently found large amounts of black oily, sandy dirt in the suction line of a natural gas compressor.
It seems the pollution has come from the discharge line as the suction line check valves has failed?
Does this make sense?
Any idea how that kind of dirt can get into a natural gas line?

 

[dcasto]

Is the gas sour? If so, it looks like "black rust" or iron sulphide.

The "oil" is most likely compressor lube or seal oil.

Can dirt get into gas lines? Yes it can.

 

[gustorf]

dcasto, thanks for the info! The gas isn't sour and all the dirt is in the suction line.
How shall compressor lube or seal oil get there?

 

[dcasto]

Minimum flow by-pass or the check valve failing or the seal oil or lube oil is flowing to the lowest pressure, the suction.

It could even be crude oil from field seperators that carry over.

 

[pmover]

valve grease . . .

how many, how often, and how much valve grease is injected in valves upstream of compressor?

any oil injection systems upstream of compressor in question?

have sample collected and sampled.

good luck!
-pmover

 

[Bobby156]

Seems your trunkline isn't clean - filtersystem doesn't work

 

[bcs5274]

frac sand mixed with lubrication oil?? seen that before

 

[gustorf]

Thanks all.
we were just informed, that the dirt is in the discharge line, not in suction.
Does this change anything? how can that get through a compressor?

 

[pmover]

ok, what type of compressor - recip, centrifugal screw, etc.?

is there a functional scrubber or filter upstream of compressor?

has the substance sample been analyzed for composition?

what is compressor application (i.e. compressor station, processing facility, refrigeration facility, etc.)?

you need to provide these details, among others, so others can aid you in getting better answers . . .

good luck!
-pmover

 

[D3znap123]

I have also had the same experience in which the suction controler would also clog off due to this black sand. Something that you may check on is if you have a witches hat still installed which is used to catch alot of this from the seporator or from the dehy in which it could also be your companys or your customers charcoal filters may have ruptured upstream, if a dehy is in the picture.
Hope I was of some help
Miguel M.