Evaluation of crude oil quality

Petroleum and Coal 01/2010; 52.
Source: DOAJ


Fourteen type crude oils originated from USA, Mexico, Africa, Middle East, Russia, Canada,Colombia, Ecuador, and Venezuela having density and sulfur in the range API = 12.1 ÷ 40.8; S =0.4 ÷ 3.3% and total acid number varying in the range TAN = 0.1 ÷ 3.72 mg KOH/g oil havebeen investigated. The studied crude oils have been classified into four groups: I group – light,low sulfur one (30 - 400 API; S ≤ 0.5 % mass); ІІ group – light, sulfur one (30-400API; S= 0, 5 -1.5 % mass); ІІІ group – heavy, high sulfur one (15-300API; S=1.5 ÷ 3.1% mass); ІV group –extra-heavy, high sulfur one (150API, S ≥3 % mass). It has been established that extra-heavycrude oils (IV group) are characterized by light fraction low content, diesel fractions low cetaneindex, vacuum gas oil fractions low K-factor and vacuum residue fractions high Conradson carboncontent. It also has been found on the base of crude oil averaged prices for June 2009 (Brentcrude oil price = 69 US $/ barrel) that the difference of the Ist and IVth group crude oil prices wasabout 9 US $/ barrel. This difference amounts up to 22 US $/ barrel, as the crude oil price rises upto 140 US $/ barrel. The high acid crude oil price (such having TAN > 0.5 mg KOH/g oil) may beapproximately 9 US $/ barrel lower than one determined on the base of density and sulfur contentfor the corresponding group.

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Article: Evaluation of crude oil quality

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    • "This procedure is reasonably well-defined and is based on the representation of the mixture of actual components that boil within a boiling point interval by hypothetical components that boil at the average boiling temperature of the interval [1] [2] . The crude oil assay typically includes TBP distillation according to ASTM D-2892, which can characterize this part of oil that boils up to 400 0 C atmospheric equivalent boiling point [3] , and vacuum distillation according to ASTM D-5236 [4] which characterizes the heavy oil obtained as a residue from the ASTM D-2892 distillation [5] [6] [7] . ASTM D-1160 vacuum distillation is also used to characterize the distillation curve of high boiling materials [8] [9] [10] [11] . "
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    • "For most of the samples the squared correlation coefficient was r 2 ~ 0.99 which is an indicator that distillation analysis was correctly performed. It was proved in many earlier studies that the boiling point distribution of oil fractions obeys the Riazi's distribution model [10] [11] [12]. Therefore, it could be used as a tool for examination of the precision of the distillation analysis. "
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