Precise determination and continuous monitoring of the Hydrocarbon Dew Point (HCDP) are essential in natural gas operations to ensure pipeline reliability, efficiency, and safety, as highlighted in ISO/TR 11150:2007. Due to natural gas compositional variations, HCDP can shift widely, with complex behaviors such as retrograde condensation making measurement particularly difficult. Conventional methods, including the Chilled Mirror Technique (CMT) and Gas Chromatography-Equation of State (GC-EOS) calculations, are associated with few drawbacks. CMT depends heavily on operator judgment and cannot deliver continuous data, while GC-EOS relies on accurate sampling and modeling, limiting its real-time applicability. This work introduces a Resistance Temperature Detector (RTD) PT100-based sensing system capable of continuous, in situ monitoring of HCDP. The sensor was tested under varied process conditions, different compositions, pressures, and flow rates before and after gas treatment. Comparative analysis with CMT and GC-EOS demonstrates that the RTD PT100 provides consistent and accurate readings with mean deviations often within ±0.21 °C for treated gas and excellent agreement with GC-EOS predictions. For untreated streams, the system showed a lower variability than spot-measurement approaches. Furthermore, black particles in pig residue were considerably reduced by RTD PT100 compared to existing methods, indicating improved process cleanliness and gas quality stability. These findings establish the RTD PT100 as a dependable solution for real-time HCDP monitoring, enabling proactive process adjustments, enhanced safety margins, and compliance with industry requirements for “measurable hydrocarbon dew point”.
Poolaiah et al. (Thu,) studied this question.