Therefore, using a gas chromatograph to determine the HCDP using an EOS provides additional valuable information from already required equipment.
The ability to calculate the HCDP at any pressure opens up some very practical applications that can significantly improve measurement and lower lost and unaccounted for energy.
A gas chromatograph that is capable of calculating the HCDP at any pressure enables a very useful operational diagnostic that can be used to avoid two-phase flow, and therefore incorrect measurement.
The producer/processor must meet the tariff while making a profit and it is this fine line that makes monitoring the HCDP so essential.
Everyone wants to find the best way of monitoring HCDP under all types of conditions.
The manual visual dew point method is the simplest and most widely used method for measuring both HCDP and water dew point (WDP) in natural gas.
The cricondentherm is the point on this curve where pressure and temperature indicate that the maximum HCDP is to be found (diagram).
Many tariffs are written with this point as the measuring point for the maximum allowable HCDP in the gas.
Capability for Harmonizing With Contract Data--Historically the working definitions of HCDP have been slightly modified and standards have been rewritten to incorporate them.
Because very little useful HCDP data existed for gases of interest to the natural gas transmission and production segments, experiments were performed to collect HCDP data on gases with a broad range of heavy hydrocarbon content at multiple pressures.
A digital video camera was mounted to the eyepiece of the dew scope to record condensation on the mirror and temperature readouts in the field of view during HCDP measurements.
Overall, the comparisons provided evidence of a trend among predicted hydrocarbon dew points: as the line pressure and heating value of a natural gas stream increase, existing equations of state are more likely to under-predict the HCDP of the stream.