Thermogravimetric description of visbreaker streams in an oil refinery

CATEGORY: VISBREAKER
Thermogravimetric description of visbreaker streams in an oil refinery

Type	Journal Article
Author	Agustín García Barneto
Author	José Ariza Carmona
URL	http://www.sciencedirect.com/science/article/pii/S0040603116302337
Volume	642
Pages	1-9
Publication	Thermochimica Acta
Date	October 20, 2016
Abstract	Chemical characterization of heavy oil fractions is impractical because of their complexity. As an alternative, thermogravimetric analysis (TGA) offers fast and valuable information about composition of streams entering and leaving visbreaker unit in oil refineries. Deconvoluting thermogravimetric curves allows thermal-based composition of visbreaking streams to be elucidated by using pseudo-components: four for visbreaking feed and seven for visbreaking residue. In both cases, some pseudo-components explains volatilization of light substances (viz. naphtha or gasoil) under 350 °C, and three explains cracking of heavy molecules around 380 °C, 411 °C and 453 °C. Obtained results make it possible to define a thermogravimetric index that characterizes composition of visbreaking samples. This index is higher in feed than in residue, and it is higher in light samples than in heavy samples. Deconvolution of TGA curves was improved by using autocatalytic kinetic based on extended Prout–Tompkins equation.