General Study of Oils from Producing Wells of the Sosninsko-Sovetsko-Medvedevskoye Field
Abstract Generated abstract
This paper presents a compositional and physicochemical characterization of oils from three producing wells of the Sosninsko-Sovetsko-Medvedevskoye field in Tomsk Oblast. Using standard measurements of elemental composition, fractional distillation, density, viscosity, pour point, vapor pressure, paraffin, resin, asphaltene, ash, salts, acids, phenols, and trace vanadium, the study compares oils from Valanginian and Hauterivian-Barremian reservoirs. The oils are described as light, low-viscosity, low-sulfur crudes with high yields of fractions boiling below 300°C, moderate resinous-asphaltene content, low ash and chloride salt contents, and insignificant vanadium levels. The authors conclude that these oils are generally of high quality and compare favorably with many oils from the “Second Baku” region.
Full Text
GENERAL STUDY OF OILS FROM PRODUCING WELLS OF THE SOSNINSKO-SOVETSKO-MEDVEDEVSKOYE FIELD
S. I. Smolyaninov, N. M. Smolyaninova, K. K. Stramkovskaya,
S. I. Khoroshko
(Presented by the Scientific-Methodological Seminar of the Chemical-Technological Faculty)
The Sosninsko-Sovetsko-Medvedevskoye oil field is located in the Aleksandrovsky District of Tomsk Oblast, 60 km northwest of the settlement of Aleksandrovo, on the right bank of the Ob River.
The field, which is large in size, was put into production in 1966. Oil was produced from three wells (Nos. 18, 27, 47).
The oils from wells 18 and 27 were extracted from reservoir B—VIII (Valanginian stage), and the oil from well 47 from reservoir A—I, stage—Hauterivian-Barremian).
In elemental composition, the oils are characterized by an insignificant sulfur content (0.65–0.75%), which is a positive factor and advantageously distinguishes the oils studied from the oils of the “Second Baku,”
Table 1
Dependence of the density and viscosity of oils on temperature
| Indicator | Well No. | −10 | 0 | 10 | 20 | 30 | 40 | 50 |
|---|---|---|---|---|---|---|---|---|
| Density, g/cm³ | 18 | 0.8442 | 0.8362 | 0.8299 | 0.8251 | |||
| Density, g/cm³ | 27 | 0.8502 | 0.8411 | 0.8347 | 0.8302 | |||
| Density, g/cm³ | 47 | 0.8629 | 0.8555 | 0.8500 | 0.8444 | |||
| Kinematic viscosity, cSt | 18 | 95.00 | 21.05 | 12.80 | 6.33 | 5.17 | 4.04 | 3.54 |
| Kinematic viscosity, cSt | 27 | 96.96 | 21.72 | 10.25 | 6.64 | 5.71 | 4.48 | 3.65 |
| Kinematic viscosity, cSt | 47 | 98.50 | 23.24 | 14.89 | 7.87 | 6.85 | 5.70 | 4.70 |
The carbon content lies within the range 84.84–85.46%, hydrogen—12.84–13.01%, nitrogen—0.21–0.41%.
These oils are distinguished by a high yield of light-boiling fractions: in distillation according to GOST 2177-59, 30.8–33.5% by volume boils off up to 200°C, and 53.0–56.5% up to 300°C.
Table 1 presents data characterizing the dependence of the density and viscosity of the oils on temperature. As can be seen from the table, the oils belong to the light type, which fully corresponds to their fractional composition. The viscosity of the oils increases sharply with decreasing temperature, especially at subzero temperatures. These regularities are confirmed by other parameters characterizing the quality of the oils (Table 2)—low molecular weight and a relatively high pour point, which changes little with heat treatment (except for the oil from well No. 47 with respect to the latter indicator).
Table 2
General characterization of the oils
| No. | Name of indicator | Unit of measurement | Well 18 | Well 27 | Well 47 |
|---|---|---|---|---|---|
| 1 | Molecular weight | 193 | 192 | 228 | |
| 2 | Pour point | °C | −18 | −16 | −36 |
| 3 | Same, without heat treatment | ″ | −16 | −18 | −6 |
| 4 | Saturated vapor pressure at 38°C | mm Hg | 162 | 234 | 340 |
| 5 | Same at 50°C | ″ | 337 | 257 | 350 |
| 6 | Paraffin content | % | 3,27 | 3,26 | 4,39 |
| 7 | Melting point of paraffin | °C | 47,0 | 47,0 | 48,0 |
| 8 | Sulfuric-acid resin content | % | 11,4 | 15,0 | 20,2 |
| 9 | Silica-gel resin content | ″ | 8,99 | 9,10 | 9,88 |
| 10 | Asphaltene content | ″ | 0,55 | 0,84 | 0,79 |
| 11 | Coking value | ″ | 1,72 | 1,85 | 1,90 |
| 12 | Ash content | ″ | 0,055 | 0,035 | 0,012 |
| 13 | Acid number | mg KOH/g | 0,034 | 0,038 | 0,038 |
| 14 | Naphthenic acid content | % | 0,025 | 0,030 | 0,019 |
| 15 | Phenol content | % | 0,011 | 0,009 | 0,012 |
| 16 | Water content | % | 0,74 | absent | 1,18 |
| 17 | Mechanical impurities | % | 0,040 | 0,035 | 0,046 |
| 18 | Vanadium content | % | 0,00019 | 0,00026 | 0,00028 |
| 19 | Salt content | mg NaCl/liter | 34 | absent | 25 |
| 20 | Flash point | °C | −13 | −11 | −15 |
The oils studied have an average content of resinous-asphaltene substances and do not differ fundamentally from oils of fields in Tyumen Oblast; however, the asphaltene content in the Tomsk oils is noticeably lower.
The oils have low ash content and a low content of chloride salts.
It should also be noted that the vanadium content in the oils is insignificant, which is a positive factor when using the heavy fractions of these oils as feedstock for catalytic cracking.
All the oils tested have a fairly high paraffin content and in this respect are similar to Shaim oil, which, however, is also characteristic of the other indicators.
Conclusions
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According to most of the characteristic indicators studied, the oils from the producing wells of the Sosninsko-Sovetsko-Medvedevskoye field are of high quality.
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A characteristic feature of the oils studied is their low density, low viscosity, low sulfur content, and high yield of fractions boiling below 300°C.
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In terms of their qualitative characteristics, the oils of this field surpass many oils from typical fields of the “Second Baku.”