Prediction of gas hydrate formation conditions based on an improved PR-Henry model

doi:10.3969/j.issn.1006-6535.2025.06.012

Abstract

Abstract: Predicting hydrate formation conditions is of great significance for the efficient development of natural gas and safe, efficient pipeline transport.To analyze the effects of ion type and salinity in formation water on hydrate formation conditions,scaled particle theory (SPT)-adjusted PR-Henry model was used to calculate the fugacity of each component in the gas-water phases.Based on this and thermodynamic theory,a calculation method was proposed to identify hydrate formation type and predict hydrate formation conditions under different temperature conditions.The study showed that for a hydrocarbon-CO₂-water mixed system,compared with traditional models,the improved model reduces the relative error between calculated hydrate equilibrium conditions and experimental data from 0.255 to 0.073,achieving good accuracy.At low salt concentrations,NaCl and CaCl₂ had similar inhibiting effects on hydrate formation,but as salinity increased,CaCl₂ inhibition was significantly greater than that of NaCl.These findings offer useful reference for gas hydrate development and safe natural gas pipeline transportation.

Key words: hydrate, salinity, phase equilibrium, PR-Henry model, statistical thermodynamics

CLC Number:

TE312

ZHANG Qian, JIANG Liangwei, LIU Fang, PENG Xiaodong, YAN Ping. Prediction of gas hydrate formation conditions based on an improved PR-Henry model[J]. Special Oil & Gas Reservoirs, 2025, 32(6): 100-106.

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