Study of structural organization of oil dispersed systems

The modeling of asphaltenes growth was done by use of lattice model of diffusion-limited Witten-Sander aggregation. Obtained value of its dimension is 1,687. For the first time asphaltene nuclear fractal dimension of the complex structural units (CSU) of different geological age oil was measured. Dimension varies from 1,604 to 2,223. In was determined that fractal nuclear dimension correlates with the age of oil grade and increase downward in field cross-section. It is shown that the fractal dimension of asphaltene aggregates structure is an integral feature of the genetic differentiation of natural oil on the degree of its maturation. Correlation between fractal dimension decrease, activation energy of dispersion environment and asphaltene concentration was experimentally determined. Evaluation of average density of asphaltene nuclear in the oil in situ was done by use of nuclear magnetic resonance without subsidence of asphaltenes by hexane or light petroleum. A reduction in the density of the fractal core with growth of its radius, which is not correlated with the geological age and average density of oil groups, was determined. Based on analysis of 353 representative sample of Perm region oil, CSU structure was monitored. For the first time characteristic intervals of nuclear size were determined with different mechanisms of asphaltene aggregation complexes. In the range of nucleus radius 20–28 nm for the first time phase transition that accompanied by preservation of specific surface energy at the border «solvate layer – core» was determined. Increase in thickness of solvate layer with size of the nucleus growth leads to anomalous reduction of the dynamic viscosity of the oil by 37.5 % rel. in average. The results can be used in the development of modern methods for control of properties of the oil disperse systems for oil production and its processing.