Development of devices for implementation pulse nonstationary waterflooding

To further improve the efficiency of the non-stationary flooding (acceleration of capillary impregnation oil closed pores) at the bottom of injection wells installed devices, creating pulses in the pumped liquid, with a packer. The article deals with a device designed for this purpose. A mathematical model of the device and output expressions to define the basic operating parameters of output. For comparison of theoretical calculations show the results of bench testing device. In view of previous research, the authors of substantiated the effectiveness of such devices for the nonstationary flooding in the system to maintain reservoir pressure. The preliminary positive data on fishing the use of these devices in the fields of NC «Rosneft» in 2015-2016.

Capillary Impregnation with Non-Linear Filtration Laws

In connection with the increasing share of low-permeability oil and gas reservoirs, of particular scientific and practical interest is the study of the characteristics of the flow of filtration processes in reservoirs characterized by non-linear filtration laws. The article presents the results of an analytical study of the features of capillary impregnation of low-permeability reservoirs characterized by non-linear filtration laws. Mathematical modeling of the impregnation processes was carried out under the assumption that the dependence of the filtration rate on the pressure gradient modulus near the zero point can be represented by a power function. It was established that, in contrast to capillary impregnation processes under the traditional linear Darcy law, the intensity of impregnation of low-permeability layers of a productive formation in a nonlinear case depends on the longitudinal pressure gradient in the formation - the larger this gradient, the higher the intensity of impregnation. It was also shown that for nonlinear filtration laws, the capillary impregnation front in a porous medium with a fluid at rest can propagate at a finite speed, which is impossible with linear filtration laws.

Влияние ультрадиспергирования на химические сдвиги рентгеновских K-линий в оксидах меди и марганца

The results of study of shifts of X-ray Kα and Kß lines of manganese and copper obtained for CuO, MnO, Mn3O4 and MnO2 oxide nanoparticles (relative to the corresponding massive materials) are presented. Oxide nanoparticles were synthesized in the pores of borosilicate glasses with an average pore diameter of 7±1 nm from the corresponding nitrates introduced into the pores by capillary impregnation. It was found, that for nanocomposites with CuO and Mn3O4 there is a small (about ~0.1 el./atom) increase in the role of 3d electrons in the chemical bonds. On the contrary, for nanocomposites with MnO2 the role of these electrons has an opposite trend.

Capillary Impregnation of Viscous Fluids in a Multi-Layered Porous Medium

Capillary impregnation of viscous fluids in porous media is useful in diagnostics, design of lab-on-chip devices and enhanced oil recovery. The impregnation of a wetting fluid in a homogeneous porous medium follows Washburn’s diffusive law. The diffusive dynamics predicts that, with the increase in permeability, the rate of spontaneous imbibition of a wetting fluid also increases. As most of the naturally occurring porous media are composed of hydrodynamically interacting layers having different properties, the impregnation in a heterogeneous porous medium is significantly different from a homogeneous porous medium. A Washburn like model has been developed in the past to predict the imbibition behavior in the layers for a hydrodynamically interacting three layered porous medium filled with a non-viscous resident phase. It was observed that the relative placement of the layers impacts the imbibition phenomena significantly. In this work, we develop a quasi one-dimensional lubrication approximation to predict the imbibition dynamics in a hydrodynamically interacting multi-layered porous medium. The generalized model shows that the arrangement of layers strongly affects the saturation of wetting phase in the porous medium, which is crucial for oil recovery and in microfluidic applications.

Development of mathematical model of extraction from lupine with cheese serum by applying low-frequency mechanical vibrations

It is noted that the model is designed to create the largest possible pressure change in the cheese whey in the extractor, since the rate of transfer of the target components is proportional to the pressure difference at the ends of the capillaries. The mathematical description of impregnation as the main or important auxiliary operation is given in detail. The equations for the impregnated part of the capillary, the ratio of impregnation rates at different times are given. From the above dependencies, the equation Washburne regarding the time of impregnation. The formulas for calculating the volume of extractant passed through the capillary, serum and forced out of the capillary air taking into account the viscous resistance of the latter. After integration of the equation of the speed of capillary impregnation of the obtained expression allows to estimate the final value of the impregnation in the initial stage. For different cases of capillary impregnation expressions are written at atmospheric pressure, vacuuming and overpressure. The introduction of dimensionless values allowed to simplify the solution and to obtain an expression for calculating the time of pore impregnation. The analysis of the equation of dimensionless impregnation time taking into account the application of low-frequency mechanical vibrations is made. It is noted that the processes of impregnation and extraction occur simultaneously, so the impregnation time is often neglected, which impoverishes the understanding of the physics of the process, reduces the accuracy of the calculation. Taking into account the diffusion unsteadiness of the process of substance transfer due to hydrodynamic unsteadiness, the equation containing the effective diffusion coefficient is written. The equation of unsteady diffusion for a spherical lupine particle in a batch extractor is supplemented with initial and boundary conditions. Taking into account the balance equation, the kinetic equation of the process is obtained. We studied the distribution of pores in the particle lupine along the radii and squares, the calculated value of the porosity of the particle. The values of De and Bi are determined by the method of graphical solution of the balance equation, the equation of kinetics and the parameters included in these equations. Conclusions on the work.

Матричный синтез монодисперсных сферических нанокомпозитных частиц SiO-=SUB=-2-=/SUB=-/GaN:Eu-=SUP=-3+-=/SUP=-

A nanocomposite in the form of monodisperse spherical mesoporous silica particles (mSiO_2) filled with GaN:Eu^3+ is synthesized by the template method. The method is based on the capillary impregnation of pores of mSiO_2 particles with a melt of crystal hydrates of gallium and europium (0.22 wt %) nitrates, followed by thermal decomposition and ammonia treatment. It is shown that nanocomposite particles contain hexagonal GaN:Eu^3+, are of spherical shape, monodisperse and do not coalesce with each other. The photoluminescence spectra of the mSiO_2/GaN:Eu^3+ particles show a group of lines characteristic of intracenter transitions in Eu^3+.