Evaluation of crude oil quality

Petroleum and Coal 01/2010; 52(1).
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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