A successful case of hydrocarbon dew point analysis during mixing of natural gases in transmission pipeline

Abstract

The occurrence of liquid condensation in natural gas accounts for new challenges during the interoperability between transmission networks, where condensation would lead to higher pressure drops, lower line capacity and may cause safety problem. A successful case of hydrocarbon dew point (HCDP) analysis is demonstrated during the mixing of natural gases in the transmission pipeline. Methods used to predict the HCDP are combined with equations of state (EOS) and characterization of C₆₊ heavy components. Predictions are compared with measured HCDP with different concentrations of mixed gases at a wide range of pressure and temperature scopes. Software named “PipeGasAnalysis” is developed and helps to systematic analyze the condensation problem, which will provide the guidance for the design and operation of the network.

Keywords

natural gas / mixing proportion / phase behaviour / hydrocarbon dew point / liquid condensation

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