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The management and prevention of hydrates are crucial for the gas industry. This study delves into the intricate challenges associated with gas hydrate formation, with a specific focus on investigating the impact of corrosion by‐products on prevention strategies. Employing a distinctive methodology, the sapphire pressure–volume temperature (PVT) cell was utilized. Experimental tests were conducted using sodium chloride (NaCl) concentrations of 1% and 3% to simulate brine solution levels at the wellhead, incorporating 3% filtrate and unfiltered iron carbonate (FeCO3) as corrosion products associated with the production process. The 1% and 3% salt concentrations were chosen to encompass a broad range of temperature depressions, reflecting common industry standards for simulating realistic environmental conditions. PVT cell test conditions ranged from 80 to 200 bar, with increments of 40 bar. The experiments investigate the effects of common pipeline salts on a monoethylene glycol (MEG)/water mixture in the presence of methane gas at typical industry high‐pressure conditions. The investigation uncovers that the introduction of salts to water, methane, and MEG solutions serves as a hydrate inhibitor, with inhibitory effects directly correlated to salt concentration. While generally hydrate growth inhibition is beneficial in natural gas pipelines, the findings indicate that elevated salt concentrations and lower pressure conditions contribute to the formation of larger hydrates, heightening the risk of surface adhesion and potentially introducing complications in piping equipment, despite the decreased temperature at which these hydrates form due to the inhibitory effects of the salts. In particular, the mixed condition of 3% NaCl and 3% FeCO3 (filtered) has the strongest effect. Examination of hydrate formation temperature and macroscopic observations suggests that the existence of substantial precipitates, as evidenced in the unfiltered FeCO3 sapphire cell experiment, may have the potential to enhance hydrate growth. [ABSTRACT FROM AUTHOR]

The influence of Ni content on corrosion and trench formation of low alloy steel in a low H2S containing sour corrosion environment was investigated. The results show that Ni decreases the total amount of corrosion by forming a passive film containing Ni components, such as NiS and Ni3S2 on the steel surface as a result of long‐term corrosion and suppressing the anodic dissolution reaction, while increasing the trench depth. It was also identified that the Ni content had a more dominant effect on trench formation in steel regardless of the tested sour environments with 0.01 bar H2S gas (pH 4.0) and 0.001 M Na2S2O3 (pH 2.7) in this study. Based on the experimental findings, the mechanism of trenching propagation by Ni was discussed from the viewpoint of changes in surface film properties and associated difference of corrosion resistance between trench‐tip and bulk surface due to the variation in Ni content. [ABSTRACT FROM AUTHOR]

Methyldiethanolamine (MDEA) is a widely used chemical in the natural gas processing industry as a solvent for CO2 and H2S capture and as a basic compound for pH stabilization corrosion control. During pH stabilization corrosion control, the removal of MDEA during the (mono)ethylene glycol (MEG) regeneration process may occur under vacuum conditions during reclamation in which the removal of salt cations is performed. Isobaric vapor-liquid equilibrium data for the binary MEG-MDEA system is presented at (20, 10 and 5) kPa and water-MDEA system at (40, 20, 10) kPa to simulate its behavior during MEG reclamation under vacuum. Vapor and liquid equilibrium concentrations of MDEA were measured using a combination of ion chromatography and refractive index. The generated experimental VLE data were correlated to the UNIQUAC, NRTL, and Wilson activity coefficient models, and the respective binary parameters were regressed. [ABSTRACT FROM AUTHOR]