Effect of Alcohols on the Rheological Properties of Tetrahydrofuran Hydrate Slurries

Abstract

Summary Hydrate formation is an issue that can have a significant negative economic impact on the oil industry. Hydrates are crystalline solids that resemble ice, usually formed in the presence of a mixture of oil/gas/water in conditions of high pressure and low temperature, similar to those found in deepwater oil production. Depending on the amount of hydrates formed, production lines can be severely affected, causing huge financial losses. Therefore, it is of great interest to understand and analyze the characteristics of the hydrates formed, and eventually identify means of mitigating hydrate formation, to reduce the production losses. In this work we analyze the effect of alcohols for hydrate mitigation through rheological characterization. We study the rheology of hydrates formed in a mixture of tetrahydrofuran (THF) and water. This is used as a model system because hydrates are formed at atmospheric pressure. Using the rheology of the model system as a baseline case, we analyze the effect of different alcohols (monoethylene glycol, ethanol, isopropanol) and concentrations on the rheology of the resulting hydrate slurries to verify and understand the capability of these additives to mitigate hydrate formation.