Colloidal Structures of Petroleum Residues Long-Lived in Metastable States

Experimental studies showed that colloidal subsystems of resins and asphaltenes in metastable state are most probably the basic carriers of the “thermal memory” effect of petroleum fluids. The structural transformations of the colloidal system of asphaltenes revealed probably are universal in character and are characteristic of petroleum residues of different geographic origin. It was found that not only thermodynamic but also kinetic control should be conducted in processes of transformation of the disperse phase of petroleum residues.__________Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 3, pp. 42 – 44, May – June, 2005.     

A Composite Additive for “Heavy” Gas-Condensate Diesel Fuel

A composite additive that decreases the cloud and solid points of GShZ gas-condensate diesel fuel, stable condensate “heavy” bottoms, to the values required by GOST 305–82 for grade “3– 45” petroleum diesel fuel, was developed from domestic feedstock. This significantly improves the performance properties of gas-condensate diesel fuel.__________Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 4, pp. 26 – 28, July – August, 2005.     

Features of Intermediate Layer Formation in Water-Oil Emulsions

New data on the mechanisms of intermediate layer formation in petroleum emulsions are reported. The possibility of structural phase transitions preceding the inversion points of these multicomponent media was experimentally demonstrated. Many features of these transitions are similar to the phase transitions in model dispersions of the Winsor III type. In manufacturing processes, the formation of undesirable “intermediate layers’ can be interpreted as the appearance of a bicontinuous phase at ratios of the volume fractions of water and crude close to unity.__________Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 4, pp. 37 – 39, July – August, 2005.     

Kinetics of alkylation of benzene with propylene in the presence of dimethyldichlorosilane

The kinetics of alkylation of benzene with propylene in the presence of dimethyldichlorosilane at 130, 150, and 170°C and 1.2–1.8 MPa was investigated. Kinetic equations were derived for a three-stage scheme of this process and its kinetic parameters were calculated. The promoting effect of water on the catalyst at a content in the reaction mixture of under 0.4 mole % was established. Transalkylation of benzene with di- and triisopropylbenzenes was investigated.Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 6, pp. 39–42, November– December, 2004     

Antiseptics Made from Petroleum Resins

Data are reported on the compositions and technology of production of safe petroleum protective creosote materials based on resinous residues and gasoils from thermal and catalytic processes.__________Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 3, pp. 51 – 54, May – June, 2005.     

Influence of soil moisture on the results of surface geochemical survey applied to petroleum exploration

The quality of results obtained from surface geochemical exploration depends not only on the character of deep petroleum accumulations but also on the influence of many sub-surface factors. One of important factors is the presence of soil moisture in the sampling interval. This research presents the influence of soil moisture on concentrations of gaseous hydrocarbons in sampled soil gases. The comparative analysis was made on for two populations of gaseous hydrocarbon (methane, ethane, propane, i-butane, n-butane, propylene, 1-butene) concentrations measured in soil gas samples collected from the water-saturated (“wet” sampling interval) and water-free (“dry” sampling interval) environments. The comparison was based upon chromatographic analyses of 2974 samples of soil gas, in which 684 samples originated from “wet” sampling intervals and 2290 samples were taken from “dry” interval. Samples were collected in the areas of known gas deposits located in the Fore-sudetic Monocline (SW Poland). Samples collected from the “wet” intervals reveal higher concentrations of almost all analyzed hydrocarbons in comparison with samples from “dry” intervals. Highest differences were observed for methane concentrations and lowest — for total alkanes C₂–C₄. The increase of concentrations in “wet” sampling intervals can be explained by sub-surface accumulation of hydrocarbons caused by decreasing permeability of water-saturated soils, by the different solubilities of alkanes and alkenes in water as well as by recent generation of methane and alkenes. Considering the results obtained from the area of the Tarchaly gas deposit, it was found that surface pattern of methane anomalies does not reflect the presence of deep gas accumulations, as well as the total alkanes C₂–C₄ distribution. Hence, the procedure was proposed of elimination of soil moisture influence on the pattern of surface methane anomalies. The procedure includes normalization of measured methane concentrations to the reference levels of geochemical background, which characterize “wet” and “dry” sampling intervals. As a result, the distribution of anomalous methane concentrations was obtained, which, along with the distribution of total alkanes C₂–C₄, confirms the presence of assessed accumulation of gaseous hydrocarbons. Therefore, the proposed method is correct and supports the application of methane indicator as a petroleum exploration tool.     

Determination of horizontal permeability from the elliptical flow of horizontal wells using conventional analysis

Besides the regular four flow regimes normally seen during a pressure test of horizontal wells, it is possible, under special circumstances, to observe such additional flow regimes as spherical, hemi-radial, linear (reservoir channel) and elliptical. The last flow regime is characterized by a slope of 0.36 of the pressure derivative curve and occurs between the early linear flow and the pseudo-radial flow periods. This may have been overlooked in horizontal well test analysis, because it is often masked by the other flow regimes, unless the conditions are just right.The elliptical flow regime has been previously mentioned by very few researchers, Issaka et al. [Issaka, M.B., Zaoral, K., Ambastha, A.K. and Mattar, L., 2000: “Determination of Horizontal Permeability Anisotropy from Horizontal Well Tests,” SPE Saudi Arabia Section Technical Symposium, Dhahran, Saudi Arabia, 21–23 October.], Chacon et al. [Chacon, A., Djebrouni, A. and Tiab, D., 2004. “Determining the Average Reservoir Pressure from Vertical and Horizontal Well Test Analysis Using Tiab's Direct Synthesis Technique”. SPE 88619, Proceedings, SPE Asia Pacific Oil & Gas Conf. & Exhibition, Perth, Australia, 18–20 October.] and Escobar et al. [Escobar, F.H., Munoz, O.F., and Sepulveda, J.A., 2004. “Horizontal Permeability Determination from the Elliptical Flow Regime for Horizontal Wells”. CT&F — Ciencia, Tecnología y Futuro. Vol. 2 Num. 5. p. 83–95. Dec.]. A methodology for its characterization has been also introduced using the pressure derivative concept and TDS technique [Escobar, F.H., Munoz, O.F., and Sepulveda, J.A., 2004. “Horizontal Permeability Determination from the Elliptical Flow Regime for Horizontal Wells”. CT&F — Ciencia, Tecnología y Futuro. Vol. 2 Num. 5. p. 83–95. Dec.]. However, conventional analysis for the characterization of this has not yet been reported in the literature. This flow regime is very useful to estimate the horizontal permeability, especially, when the pseudo-radial flow is very short or unclear, or simply, when it is desired to verify that estimation.In this paper, equations for the estimation of the horizontal permeability and elliptical skin factor are developed for both gas and oil horizontal wells, so that the mentioned parameters can be estimated, respectively, from the slope and intercept of linear plot of pressure versus time to the power 0.36. The equations were successfully tested with two field examples previously worked in the literature.     

Thermodynamics and Mechanics of the Deformation of “Cross-Linked” Elastomers

Kinematic forms of isothermal deformation of resins or other “cross-linked” elastomers are discussed: homogeneous uniaxial tension, simple homogeneous shear deformation, and biaxial orthogonal homogeneous deformation.It is shown that not only the conformational entropy of the state of the micromolecular structure changes, but also variation in the internal energy of this structure is possible during equilibrium isothermal deformation of “ cross-linked” elastomers.__________Translated from Khimicheskoe i Neftegazovoe Mashinostroenie, No. 6, pp. 3–5, June, 2005.     

Rheological evidence of structural phase transitions in asphaltene-containing petroleum fluids

The aim of this paper is to provide data on the rheological/structural properties of “synthetic oils,” composed of light hydrocarbons (toluene) and a heavy fraction, containing asphaltenes (vacuum residue, VR). Samples with asphaltene concentrations 20–85 g/l have been studied at temperatures 0–60 °C and shear rates up to 1500 s⁻¹. The non-Newtonian flow curves were approximated by the Bingham and the Herschel–Bulkley models to determine the apparent yield stress and the shear-rate exponent as functions of the asphaltene concentration and the temperature. Sharp variations of these parameters were attributed to formation/destruction of extended ordered structures in asphaltene colloid suspensions. Structural changes were observed in the temperature range 20–30 °C, particularly important for industrial processes of reservoir development and pipeline transportation. A molecular model of the observed macroscopic effects takes into account possible first-order structural phase transitions in the nanometer-size resin/asphaltene colloid microparticles.     

Expanding Feedstock Resources for Manufacture of Vaseline

An alternative to petrolatum in feedstock for manufacture of medicinal Vaseline from Azerbaidzhan crudes was sought. The feedstock, adsorbent, and processing conditions selected increase the yield of Vaseline from 35–40 to 70–75% while reducing formation of difficult to use wastes.__________Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 3, pp. 18 – 19, May – June, 2005.     

Asphalt production technology. From engineering art to science

In the last third of the last century, important progress was made in developing the scientific basis for oxidized asphalt production technology. The classification of crude oils and mathematical model developed allow quantitatively predicting the basic parameters of asphalt production based on vacuum distillation and oxidation process using the reference properties of the crude oil.Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 6, pp. 16–22, November– December, 2004     

Plantaricin MG active against Gram-negative bacteria produced by Lactobacillus plantarum KLDS1.0391 isolated from “Jiaoke”, a traditional fermented cream from China

A bacteriocin named plantaricin MG produced by Lactobacillus plantarum KLDS1.0391 which was isolated from “Jiaoke”, a traditional, naturally fermented cream from Inner Mongolia in China is reported in this article. Plantaricin MG was purified by ammonium sulfate precipitation followed by sequential gel filtration chromatography and reverse-phase chromatography. Mass spectrometry analysis showed the mass of plantaricin MG to be approximately 2180 Da. The bacteriocin showed a broad inhibitory activity against Gram-positive and Gram-negative bacteria including Listeria monocytogenes, Staphylococcus aureus, Salmonella typhimurium and Escherichia coli. The bacteriocin was extremely heat-stable (30 min at 121 °C) and remained active after incubation at pH 2.0–10.0. It was found to be sensitive to proteolytic enzymes (pepsin, trypsin, papain, α-chymotrypsin, proteinase K, Neutrase and Alcalase). The mode of action of plantaricin MG was identified as bactericidal.     

Assembly of asphaltene molecular aggregates as studied by near-UV/visible spectroscopy: II. Concentration dependencies of absorptivities

The properties of molecular aggregation in toluene solutions of a crude oil and solid asphaltenes are determined almost solely by the concentration of asphaltenes, as shown by absorptivity measurements at 315–750 nm. From non-monotonic concentration dependencies of absorptivities, it is concluded that asphaltene monomers are abundant in solutions with asphaltene concentrations below 1–5 mg/l, while molecular aggregates are effectively formed above 20–25 mg/l. The most stable oligomers are a dimer and a dimer pair (Yen's “nanocrystallite” [NC]). Nanocrystallites act as building blocks for more complex aggregates at asphaltene concentrations exceeding 90–100 mg/l. These optical absorption results are supported by studies of Rayleigh scattering in asphaltene solutions.     

Group composition and properties of petroleum wax fractions

The group chemical composition and physicomechanical properties of petroleum wax fractions are investigated. The mechanism of their change with an increase in the average distillation temperature is determined.Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 1, pp. 47 – 48, January – February, 2005.     

Calculation of Fuel Viscosity in the Linear Programming Model

Use of the standard tools in the modeling system with conversion of the viscosity values at the measurement temperature to the values at 50°C is recommended for representing the viscosity of middle-distillate and residual fuels in the linear programming model.__________Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 4, pp. 51 – 52, July – August, 2005.     

Crude oil from the Chirag field

The crude oil from a promising new offshore field in Azerbaidzhan — Chirag — is light, low-sulfur, low-resin, and waxy. Its naphtha cuts are characterized by low octane numbers. They can be used as components of automotive gasolines. Brand KO-20 lamp kerosene can be obtained from light kerosene cuts. Catalytic dewaxing must be conducted on the 150–280°C cut to manufacture jet fuel. The diesel cuts are favorable feedstock for manufacturing summer diesel fuel. The potential content of base oils with a viscosity index of 75–89 is 24.64 wt. % in crude oil.Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 6, pp. 35–38, November–December, 2004.     

Interrelation of hydrogenation catalyst quality and the materials of construction in catalyst manufacturing equipment

Translated fromKhimiya i Tekhnologiya Topliv i Masel, No. 2, pp. 37–38, March–April, 1946.     

Use of hydroxy acids from synthetic fatty acids still residue in asphalt production

Summary The introduction of 10–15% of a synthetic hydroxy acids concentrate, calculated on the feedstock being oxidized, considerably improves the oxidation process parameters and enables asphalts having specific rheological properties to be obtained. The rate of feedstock oxidation is increased by a factor of 1.5–2.5, the breaking point of the asphalt products is reduced to –30 and even down to –40°C, the range of plasticity reaches 90–100°C and above (with a penetration of 60–130), the asphalts exhibit an excellent adhesion to both acidic and basic stony materials. The hydroxy acids concentrate may be used as a surface-active additive, which, when added to asphalt to the extent of 0.5–1%, considerably improves the adhesion of the asphalt to stony materials.Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 12, pp. 29–32, December, 1966.     

Alternative fuels of plant origin. Determination of fractional and chemical compositions

The fractional compositions of fatty acid methyl esters from rape and sunflower oils were determined by the method in GOST 2177-99. The data obtained can be used to calculate the characteristic temperatures and thermophysical parameters of biofuels. The difference in the boiling points of the esters and their vapors was established. The ingredients of the biofuels and their fractions were determined by gas-liquid chromatography. Fuels of plant origin evaporate in a narrow temperature range so that the fatty acid methyl esters are distributed very unevenly over all fractions. The results obtained can be used to create an adequate mathematical model of evaporation of biofuel in the diesel cylinder.Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 1, pp. 29 – 34, January – February, 2005.     

Inactivation of Anisakis simplex larvae in raw fish using high hydrostatic pressure treatments

The nematode larvae of the Anisakis genus are one of the main health hazards for consumers of raw fish or similar, such as “carpaccio”, and cold smoked or marinated products.This study evaluated the efficacy of high hydrostatic pressure treatments on Anisakis larvae in mackerel (Scomber scombrus) from the North Sea. From the treatment parameters studied, a combination of 300 MPa for 5 min resulted as being capable of inactivating 100% of the larvae present in the tissues of the fish treated. Biomolecular examination confirmed their main belonging to the species Anisakis simplex sensu stricto.The use of this technology is for the treatment of other fatty fish such as sardines and anchovies prior to marinating.