Eventos Anais de eventos
ENCIT 2018
Brazilian Congress of Thermal Sciences and Engineering
INFLUENCE OF SHEAR HISTORY ON THE RHEOLOGICAL BEHAVIOR AND CRISTAL MORPHOLOGY OF WAXY OILS
Submission Author:
Diogo Elias da Vinha Andrade , RS
Co-Authors:
Lavinia Pieta Schiessl, Diogo Elias da Vinha Andrade, Cezar Otaviano Ribeiro Negrao
Presenter: Lavinia Pieta Schiessl
doi://10.26678/ABCM.ENCIT2018.CIT18-0214
Abstract
The pipelines used in the production and transportation of waxy crude oils are in contact with the ocean floor at approximately 4 °C. The interruption of the crude oil flow may cause the oil gelation. The wax crystallization is the responsible for this phenomenon that becomes one of the major problems in production and transportation of waxy crude oil. Pressures required to break up the gel and restart the flow are increased in large proportions. The literature shows that this gelled structure is highly influenced by the thermal and shear histories. The influence of shear rate during cooling on the gel strength and on the morphology of paraffin crystals is investigated in this paper. The evaluation of these effects is based on rheological experiments performed with dynamic cooling. Moreover, the visualization of microscopic structure of the crystal was possible with the RheoscopeTM system coupled to the rheometer. The results show that higher shear rates result in higher gel strength. It can also be anticipated that the size of wax crystals formed are smaller when a shear rate during the cooling is applied then the crystals precipitated in a static cooling
Keywords
wax crystallization, Rheological Experiments, Shear history, Gel Strength, crystal morphology
