A Review of Laboratory-Scale Research on Upgrading Heavy Oil in Supercritical Water

Abstract

Abstract:With the growing demand for energy and the depletion of conventional crude oil, heavy oil in huge reserve has attracted extensive attention. However, heavy oil cannot be directly refined by existing processes unless they are upgraded due to its complex composition and high concentration of heteroatoms (N, S, Ni, V, etc.). Of the variety of techniques for heavy oil upgrading, supercritical water (SCW) is gaining popularity because of its excellent ability to convert heavy oil into valued, clean light oil by the suppression of coke formation and the removal of heteroatoms. Based on the current status of this research around the world, heavy oil upgrading in SCW is summarized from three aspects: Transformation of hydrocarbons, suppression of coke, and removal of heteroatoms. In this work, the challenge and future development of the orientation of upgrading heavy oil in SCW are pointed out.

Heavy Oil Upgrading in the Presence of Water

“…Другое достоинство сверхкритической воды -ее малая полярность (диэлектриче-ская проницаемость (ε) СКВ может варьироваться от 2 до 30 [50]) и низкая вязкость при сравнительно высокой плотности [14]. Поэтому СКВ считается хорошим растворителем неполярных органических соединений, в том числе углеводородов, который обладает высокой проницаемостью среды, обеспечивающей хороший массообмен [14].…”

“…Способность СКВ смешиваться с угле-водородами и возможность диспергировать трудно-либо нерастворимые в СКВ высоко-молекулярные углеводороды с образованием эмульсий с ними приводит к снижению вы-хода кокса и увеличению выхода жидких продуктов [52]. Кроме того, СКВ используют для одновременной экстракции и облагораживания битуминозных песков и нефтесланцев [50].…”

Upgrading of crude oil in supercritical water: A five-lumped kinetic model

“…c = 0.31 g/cm 3 ) [2][3][4]. With its solvent properties and potential ability to donate hydrogen [5,6], SCW could take part in reaction as a solvent as well as a reactant or even catalyst [7][8][9][10] to transform the large molecules. Since SCW has a lower viscosity coefficient which significantly accelerates mass transfer rate and a higher dissociation constant which improves its ability to catalyze chemical reactions [11,12], it was believed that those unique properties of SCW can have a positive influence on the upgrading of heavy components in oil reservoirs.…”

Sulfur removal from crude oil using supercritical water

“…ICATION CONTACT Ayhan Demirbas ayhandemirbas@hotmail.com Faculty of Engineering, Department of Industrial Engineering, King Abdulaziz University, Jeddah, Saudi Arabia. With the growing demand for energy and the depletion of conventional crude oil, heavy oil in huge reserve has attracted extensive attention (Li et al, 2015). Inorganic materials of crude oil contain a number of inorganic constituents, especially sulfur, which plays an important role in almost all fueling systems.…”