Determination of Hydrate Phase Equilibrium Curve Using High-Pressure Visual Cell

Document Type: Research Note

Authors

Research Institute of Petroleum Industry (RIPI), P.O. Box 18745-4163 Tehran, I.R. IRAN

Abstract

This study aimed to construct the hydrate three-phase equilibrium curves for two typical Iranian gas reservoir samples using a high-pressure visual cell. To do so, complete analysis of the reservoir fluids was obtained by different techniques of composition analysis i.e. gas chromatography (GC) and detailed hydrocarbon analysis (DHA). Using high-pressure visual cell the hydrate phase equilibrium curve was obtained by measuring the hydrate formation temperature in each pressure level. By means of commercial hydrate software, hydrate formation temperature was predicted in each specified pressure level. Comparing the results showed that the experimental data are in good agreement with the simulator results. Using the experiments results, hydrate phase equilibrium curves were constructed in order to depict the safe and unsafe regions of the hydrate formation zones for two typical Iranian gas reservoir samples.

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