Effect of the reaction times on the thermal visbreaking process of heavy hydrocarbon feedstock

Abstract

© 2019, International Multidisciplinary Scientific Geoconference. All rights reserved. Heavy hydrocarbon feedstocks including heavy and extra-heavy oils produced from oilsands reservoirs have a high viscosity, which cause a big challenge to their productions and pipeline transportations. Techniques to reduce the viscosity at low incremental production cost are desirable. Thermal decompositions of these resources-derived bitumen at temperatures of 250 °C was explored as a prospect strategy for viscosity reduction. In this work, thermal visbreaking experiments were carried out in a stainless-steel 350-ml batch parr reactor. In a typical experiment, the reactor was loaded with crude oil (from Tatarstan region Russia) and water at a weight ratio of 2:1, respectively. Moreover, thermal visbreaking experiments were conducted under different reaction times (12, 24 and 48 hours). The properties of the initial oil along with the liquid products obtained after reactions were analyzed including viscosity, elemental analysis, n-alkanes distribution and SARA analysis. Results show that, thermal visbreaking under different reaction times lead to various upgrading degree. In addition, at all reaction times, changes in the chemical and physical nature of the upgraded oil were observed within 12 h of reaction time, and changes continued as reaction time was extended to a period of 24 and 48 h. Further, the content of resins and asphaltenes decreased and the amount of saturates and aromatics were increased. Eventually, there are no big different in the upgrading degree between reaction time of 24 and 48 h.