Upgrading Residues to Maximize Distillate Yields with UOP Uniflex^TM Process

Abstract

Never before have refiners faced the challenges caused by dramatic changes in crude prices and refinery margins. However some worldwide trends have not changed, such as the need to shift refinery product distributions to a more diesel-oriented slate and to reduce residue fuel oil production. The required shift from gasoline to distillate fuels cannot be accomplished solely by modifications to current hydrocracking or FCC operations. New technologies will be required that achieve higher non-distillable conversion and increased selectivity to distillate-range products. Ideally, these technologies should be both cost-effective and commercially proven. UOP has responded to the needs for increased distillate yield and non-distillable conversion with the introduction of its latest residue upgrading technology offering, the UOP Uniflex Process. This high-conversion slurry hydrocracking technology contains elements of a commercially-proven slurry reaction system and the UOP Unicracking TM and Unionfining TM technologies. The Uniflex Process can achieve non-distillable conversion levels in excess of 90 wt% with distillate yield over 50 vol%. This paper discusses the features of the Uniflex Process technology, its yield and economic advantages over conventional residue upgrading technologies, and other applications of the technology. KeywordsResidue, Conversion, Upgrading, Hydrocracking, Slurry Existing Residue Conversion SolutionsConventional residue conversion solutions are well developed and, for the most part, operate efficiently within their technical constraints. Figure 1 illustrates the worldwide distribution of the major residue conversion technologies which refiners have installed. Thermal technologies such as visbreaking and coking account for approximately two-thirds of this installed capacity, with hydroprocessing, redeuced fluid catalytic cracking (RFCC) and solvent deasphalting, to a lesser extent, making up the remainder. Visbreaking and Delayed CokingVisbreaking is the oldest of all residue upgrading technologies. The large number of installed visbreakers reflects refiners' needs to minimize residue fuel oil cutter stocks. Few new visbreaking projects are being considered primarily because a visbreaker's major product is residue fuel oil for which demand is not increasing.A significant number of recent projects have selected delayed coking due to the technology's ability to fully This paper was presented at the Commemorative Int'l Symp. on the 50th Anniversary of the Japan Petroleum Institute, Tokyo, Japan, Nov. 4-7, 2008. ＊ To whom correspondence should be addressed. ＊ E-mail: Dan.Gillis@uop.com convert non-distillables. The product yields, consisting of light ends, naphtha, distillates, heavy coker gas oil (HCGO), and the byproduct coke are dependant on the feedstock qualities. The HCGO product is suitable for feedstock to downstream hydroprocessing, hydrocracking, and FCC units. For these reasons, the majority of recent grass root and major refinery expansion projects have selected the combination of d...

Combined process schemes for upgrading of heavy petroleum

“…This integration would be via selective routing of each unit's streams to the other unit and sharing of infrastructure and light-ends fractionation systems [69]. Fig.…”

“…Beside the addition of the Uniflex Process reactor there would be the requirement for some additional fractionation equipment to separate the pitch stream from the other Uniflex products before they are processed in the main RHDT reactors. The investment for this approach would be less than the cost of a delayed coking process [69].…”

n-Hexadecane hydrocracking Single-Event MicroKinetics on Pt/H-beta

“…Hydrocracking is a wellknown refinery process which increases the overall quality of heavy hydrocarbon mixtures by means of consecutive isomerization and cracking reactions [1]. Desulfurization, denitrogenation and dearomatization typically precede hydrocracking reactions and give rise to the 'clean' reputation of hydroprocessed products which is a great stimulus for the utilization of hydroconversion units in residue upgrading [2,3]. Hydrocracking is also ideally suited for the production of high-value middle distillates from Fischer-Tropsch (FT)…”

Predictive correlations for thermal upgrading of petroleum residues

“…Various upgrading strategies exist to convert heavy oils to valuable products. The so-called carbon rejection or thermal processing routes are the most widely used in refineries owing to their simple operation, lower cost, and flexibility to handle any type of residue [2][3][4][5]. Thermal upgrading technologies have accounted for about 64% of the worldwide residue processing capacity [2].…”

“…The so-called carbon rejection or thermal processing routes are the most widely used in refineries owing to their simple operation, lower cost, and flexibility to handle any type of residue [2][3][4][5]. Thermal upgrading technologies have accounted for about 64% of the worldwide residue processing capacity [2]. Excellent reviews have been published on visbreaking [3][4][5] and delayed coking [6][7][8] which address the chemistry, kinetics, and/or economies of the process.…”