Introduction to crude oil wax crystallization kinetics: Process modeling

We developed a method for measuring and monitoring the crystallization kinetics of waxy crude oils under quiescent milieu. Using a setup based on a cross-polar microscope (CPM), coupled with a high-resolution, autoranging picoammeter, power meter connected to a light detector and a high-definition-high-resolution image processing, we have been able to capture wax particle growth from 1 micron and higher sizes. Both isothermal and non-isothermal kinetics processes were studied. Analysis of the continuous wax particles nucleation, as well as their growth process, of various oil samples from different geographical locations is presented. Results indicate some degree of similarities to trends observed in crystallization kinetics described by both Ozawa (Polymer 1971, 12, 150) for non-isothermal kinetics and Avrami (J. Chem. Phys. 1939, 7, 1103) for isothermal kinetics. Empirical models for both isothermal and non-isothermal crude oils crystallization cases are introduced.