Commercial Properties of South Cheremshan Crude Oil
Abstract Generated abstract
This paper evaluates the commercial product potential of low-sulfur, paraffinic crude oil from the South Cheremshan field in Tomsk Oblast using laboratory distillation and standard quality measurements of straight-run fractions. The study characterizes gasoline, jet fuel, kerosene, diesel, catalytic cracking feedstock, oil, and residual fuel fractions by boiling range, yield, sulfur content, hydrocarbon composition, viscosity, cold-flow properties, octane or cetane number, and related indicators. The results suggest that the crude can yield substantial light fractions, gasoline components with low octane numbers, a 120 to 240°C fraction meeting TS-1 jet fuel requirements, a 150 to 350°C fraction suitable as summer diesel fuel, and a 350 to 450°C fraction suitable for catalytic cracking, while also offering potential production of distillate and residual oils and several grades of fuel oil.
Full Text
Commercial Properties of South Cheremshan Oil
K. K. STRAMKOVSKAYA, N. M. SMOLYANINOVA, V. K. ZHURBA,
G. B. NEMIROVSKAYA, T. A. ANTONOVA
(Presented by the scientific-methodological seminar of the organic departments of the Faculty of Chemical Technology)
The oil of the South Cheremshan field in Tomsk Oblast is low-sulfur and paraffinic, and has a high yield of fractions boiling up to 200 and 300°C (31.4% and 51.8%, respectively). The straight-run fractions of this oil (sample from well 335, formation A-XII), obtained in the laboratory ARN-2 apparatus, were studied as commercial products. The principal indicators are given in the table.
The gasoline fractions of this oil are characterized by the absence of sulfur compounds, low acidity, and a high content of paraffinic hydrocarbons. Thus, the fraction with b.p.—200°C contains 85% paraffin-naphthenic and 15% aromatic hydrocarbons. The increased concentration of paraffinic hydrocarbons accounts for the low octane numbers of the gasoline fractions (52–66 points in neat form). They can serve only as components of motor gasolines.
The fraction boiling within the range 120–240°C, by all the most important indicators, meets the GOST standard for jet fuel of grade TS-1. It has a high density (0.7950), releases 10,300 kcal/kg of heat on combustion, and also begins to crystallize at a very low temperature (−64°C). The content in it of aromatic hydrocarbons, which increase carbon deposition in the engine, does not exceed the standard (21%). The 120–280°C fraction has an elevated content of aromatic hydrocarbons (22%) and a high initial crystallization temperature (−52°C). This fraction may serve as a component in the production of jet fuels.
Data on the quality of kerosene distillates show that lighting kerosene can be obtained from South Cheremshan oil in an amount of 31.9%. These fractions cannot be used as tractor fuel owing to their low octane numbers.
The 150–350°C fraction, in terms of cetane number (48), viscosity level ($\nu_{20}$ 3.25 cSt), pour point (−40°C), and other indicators, meets the GOST standard for summer diesel fuel. The other isolated fractions (200–350°C and 240–350°C) have a high cloud point and can serve only as components for obtaining diesel fuels.
The cut boiling within the range 350–450°C is a good feedstock for catalytic cracking. It contains 53% paraffin-naphthenic hydrocarbons and 44% aromatic hydrocarbons. This feedstock has low sulfur content, 0.79%, but a significant amount of vanadium.
Table 1. Characteristics of commercial products from oil of the South Cheremshan field
| Distillation temperature, °C | Oil yield, wt. % | Specific gravity, $d_4^{20}$ | Viscosity, cSt at 50°C | Viscosity, cSt at 20°C | Total sulfur content, % | Solidification point, °C | Flash point in closed cup, °C | Cloud point, °C | Onset of crystallization, °C | Iodine number, g iodine per 100 g fuel | Octane number, neat | Cetane number | Aromatic hydrocarbons content, % | Coking tendency, % | Non-smoking flame height, mm | Acidity, mg KOH per 100 ml fraction |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Gasoline fractions | ||||||||||||||||
| IBP—85 | 8.2 | 0.6700 | — | — | absent | — | — | — | — | — | 66.4 | — | — | — | — | absent |
| IBP—120 | 15.6 | 0.7070 | — | — | absent | — | — | — | — | — | 61.0 | — | — | — | — | absent |
| IBP—150 | 21.6 | 0.7265 | — | — | absent | — | — | — | — | — | 55.6 | — | — | 15 | — | 0.04 |
| IBP—200 | 31.4 | 0.7475 | — | — | absent | — | — | — | — | — | 52.2 | — | — | — | — | 0.06 |
| Jet fuels | ||||||||||||||||
| 120—240 | 23.3 | 0.7950 | 1.45 | 4.67* | absent | — | 31 | —66 | — | 0.22 | — | — | 21 | — | 26 | 0.36 |
| 120—280 | 30.3 | 0.8105 | 1.75 | 7.54* | 0.03 | — | 35 | —51 | — | 0.32 | — | — | 22 | — | 24 | 0.55 |
| Kerosene distillates | ||||||||||||||||
| 150—280 | 24.3 | 0.8225 | — | — | 0.06 | — | 54 | —25 | — | — | 20 | — | — | — | 24 | 0.78 |
| 150—320 | 31.4 | 0.8341 | — | — | 0.09 | — | 60 | —17 | — | — | 19 | — | — | — | 23 | 0.97 |
| Diesel fuel | ||||||||||||||||
| 150—350 | 35.3 | 0.8400 | 3.25 | 1.85 | 0.11 | —40 | 61 | —19 | — | 0.81 | — | 48 | — | 0.01 | — | 1.36 |
| 200—350 | 26.0 | 0.8505 | 4.90 | 2.60 | 0.20 | —25 | 96 | —13 | — | 0.91 | — | 51 | — | 0.01 | — | 2.35 |
| 240—350 | 18.5 | 0.8560 | 7.25 | 3.35 | 0.32 | —18 | 127 | —8 | — | 1.01 | — | 54 | — | 0.01 | — | 3.44 |
| Raw material for catalytic cracking and manufacture of oils | ||||||||||||||||
| 350—450 | 16.2 | 0.9115 | 19.10 | — | 0.79 | 15 | — | — | — | — | — | — | 44 | 0.10 | — | — |
* At a temperature of minus 40°C.
Fig. 1. Curves of the dependence of oil properties on the depth of adsorption separation of the 350–450°C oil fraction from the South Cheremshan field.
Fig. 2. Curves of the dependence of oil properties on the depth of adsorption separation of the residue above 450°C of oil from the South Cheremshan field.
Fig. 3. Characteristics of oil residues from the South Cheremshan field.
0.0015% and nitrogen 0.29%; however, the coking value is low—0.10%. The results of adsorption separation on silica gel according to GOST 11244-65 for the 350–450°C fraction and the residue boiling above 450°C, shown in Figs. 1 and 2, make it possible to determine the potential content of high-quality oils in this crude. According to Fig. 1, the yield of distillate oils with viscosity index (VI) 85 is 12.3%, and with VI 100, 11.2%. The potential content of residual oils (Fig. 2) with VI 85 is 2%. The total potential content of oils with VI 85 in South Cheremshan crude is 14.3% on crude oil.
The characteristics of residues of different depths of withdrawal (Fig. 3) indicate the possibility of obtaining fuel oils of grades 40, 100, and 200, with yields of 43.7; 37.5; and 37.7%, respectively.