STUDY OF THE PHYSICOCHEMICAL PROPERTIES AND FRACTIONAL COMPOSITION OF CRUDE OILS FROM THE LUGINETSKOE AND OLENYE FIELDS OF TOMSK OBLAST AND A REFERENCE CRUDE OIL

N. M. SMOLYANINOVA, L. A. GOREVAYA, T. F. BULYSHEVA

(Presented by the Scientific-Methodological Seminar of the Organic Departments)

The present work is devoted to the study of the physicochemical properties and fractional composition of the Luginetskaya, Olenya, and reference crude oils.

The Luginetskoe field was discovered in 1967. It is located in the Kargasok District of Tomsk Oblast. The field is a mixed gas-condensate–oil field with an oil pool of commercial importance.

The Olenye field is the largest of the group of fields of the Kaimysov arch. It is also located in the Kargasok District. The productive bed was penetrated in the depth interval 2533.2–2559.6 m.

The reference crude oil is a mixture of oils from four fields of the Nizhnevartovsk arch (Samotlor, Megion, Vatinsk, and Sovetskoe). The characteristics of the oil sampling points are given in Table 1.

Table 1

Characteristics of oil sampling points

The physicochemical characteristics of the Luginetskaya, Olenya, and reference crude oils are given in Table 2. As can be seen from Table 2, the oils of the Luginetskoe and Olenye fields are low-sulfur and low-resin. They are characterized by a low density \((\rho^{20}_{4}—0.8157—0.8350)\),

Table 2

Physicochemical characteristics of the crudes

low molecular weight (151–174), low viscosity ($\nu_{20}$—3.04–5.24 cSt), and a considerable paraffin content (3.50–4.20%). The reference crude, in comparison with the Olenye and Luginetskoe crudes, has a higher density ($\rho^{20}_{4}$—0.8589) and molecular weight (209), and is distinguished by a considerable sulfur content (1.33%).

The data on fractional composition (Table 3) show that the Luginetskoe and Olenye crudes give higher yields of light fractions: up to 200°C, 36–39% distills over; up to 300°C, 59%. The yield of the fraction up to 200°C in the reference crude is 26.5%, and up to 300°C, 50.0%.

Table 3

Fractional composition of the crudes (according to GOST 2177-59)

Fig. 1. Distillation curves for Olenye crude oil

One of the most important characteristics of crude oils is their distillation curves, which establish the dependence of fraction yields on boiling temperatures and determine the quality of the fractions obtained (Figs. 1, 2, 3).

To obtain the distillation curves, the crude oil was subjected to atmospheric-vacuum rectification on an ARN-2 apparatus, with withdrawal of three-percent fractions, which were characterized by specific gravity, refractive index, viscosity, molecular weight, pour point, and sulfur content.

The results of the study show that the crude oils (as industrial raw materials) possess a number of positive properties. Owing to their significant content of light fractions, they can be used in the production of various liquid fuels.

From the same standpoint, a very valuable quality is their low sulfur content.

Conclusions

1. A study was carried out of the fractional composition and physicochemical characteristics of three crude oils (Luginetskoe, Olenye, and reference).

Fig. 2. Distillation curves of the reference crude oil

1. It has been established that the Luginetskoe and Olenye crude oils are characterized by a high content of light fractions.

2. Compared with the Olenye and Luginetskoe crude oils, the reference crude oil has an increased sulfur content.

Fig. 3. Distillation curves of Luginets crude oil

Visible labels in the figure:

• \(d_4^{20}\)
• \(n_D^{20}\)
• \(t^\circ\mathrm{C}\)
• mol. wt.
• yield, %
• paraffin, %
• sulfur content, %
• pour point, °C
• \(t^\circ_{\text{boil}}\)
• \(M_B\)
• \(t^\circ_{\text{flash}}\)
• \(S\)