Acceptable Limit of CO2 in Compressible Natural Gas
Acceptable Limit of CO2 in Compressible Natural Gas
(OP)
I am working on a natural gas compressor application where we will be compressing natural gas (1050 BTU rating) from 0-20 psig suction pressure to 150 psig discharge pressure. I am concerned about 10% CO2 content in the natural gas along with low percentage of water vapor in the natural gas. What are guidelines for acceptable concentrations of CO2 when potential of carbonic gas can be created when natural gas is compressed with presence of water vapor. Any help would be appreciated.
DERAILH
DERAILH





RE: Acceptable Limit of CO2 in Compressible Natural Gas
I've always set the cut off at a partial pressure of 25 psia before going to a softer metalurgy or stainless.
If you are concerned, just make the 2nd cooler tubes, piping and scrubber of 304 stainless. Or huse heay wall materials and monitor the thickness.
RE: Acceptable Limit of CO2 in Compressible Natural Gas
Steve Jones
Materials & Corrosion Engineer
http://www.linkedin.com/pub/8/83b/b04
RE: Acceptable Limit of CO2 in Compressible Natural Gas
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"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/
RE: Acceptable Limit of CO2 in Compressible Natural Gas
The gas will usually exit the compressor at a temperature far in excess of the water dew point which will allow carbon steel piping with some nominal corrosion allowance to cater for any shut in condensation scenarios (the same as for the compressor). The CO2 corrosion problem tends to rear its ugly head again at the discharge cooler where the temperature is brought down near the water dew point. It needs a proper process and corrosion engineering assessment to ensure technical integrity.
Steve Jones
Materials & Corrosion Engineer
http://www.linkedin.com/pub/8/83b/b04