May 5, 2024
Amir Abbas Izadpanah

Amir Abbas Izadpanah

Academic Rank: Associate professor
Address: -
Degree: Ph.D in -
Phone: -
Faculty: Faculty of Petroleum, Gas and Petrochemical Engineering

Research

Title
Thermodynamic Modelling of Hydrate Formation Conditions for Water-Soluble Structure H Hydrate Former
Type Thesis
Keywords
Gas Hydrate; Clathrate Hydrate; Structure H (sH); Water-Soluble Hydrate Former; 1-Methylpiperidine; 2-Methylpiperidine; 3-Methylpiperidine; 4-Methylpiperidine; Hexamethyleneimine; Methane.
Researchers somayeh moradian (Student) , Amir Abbas Izadpanah (Primary advisor) , Amir H. Mohammadi (Advisor)

Abstract

There are three typical thermodynamic models to determine structure H (sH) hydrate stability conditions i.e. van der Waals-Platteeuw based model developed by Mehta and Sloan, the Chen-Guo model introduced by Chen and Guo, and the Klauda-Sandler model applied by Sinehbaghizadeh et al. and other researchers. These thermodynamic models are typically used for water-immiscible or slightly soluble sH hydrate formers e.g. methylcyclopentane, methylcyclohexane, 2,2-dimethylbutane, etc. . However, some sH clathrate hydrate formers are soluble in water such as 1-methylpiperidine, 2-methylpiperidine, 3-methylpiperidine, 4-methylpiperidine and hexamethyleneimine. In this study, the Chen-Guo , the Mehta-Sloan and the Klauda-Sandler models were used to model sH hydrate stability conditions for 1-methylpiperidine , 2-methylpiperidine , 3-methylpiperidine, 4-methylpiperidine and hexamethyleneimine with methane as a help gas. The aqueous phase behavior containing these components are modeled using the NRTL activity coefficient model. Although all three models show errors of less than 5%, Mehta-Sloan model results are in a better agreement with the experimental data with 0.29% of average absolute error in comparison with the Chen-Guo and the Klauda-Sandler model results with 0.76% and 1.15% average absolute error respectively for all mentioned water-soluble hydrate formers. Sensitivity analysis on each of the fitted parameters for all three models was done by ±5% changes to observe which parameters have the most effect on the modelling conditions. In the Chen-Guo hydrate model, the sensitivity effect of C' is more than A' and B'. In the Mehta-Sloan hydrate model, σ is the most significant sensitive parameter, In the Klauda-Sandler model, D has the highest sensitivity among other parameters.