Nowadays, there are significant heavy high-viscosity oil reserves in the Russian Federation with oil recovery coefficient not higher than 0.25-0.29 even with applying modern and efficient methods of oil fields development. Thermal methods are the most promising out of the existing ways of development, main disadvantage of which is large material costs, leading to the significant rise in the cost of extracted oil. Thus, creating more efficient thermal methods and improving the existing ones, is the task of great importance in oil production. One of the promising trends in enhancing thermal methods of oil recovery is the development of bottomhole electric steam generators. Compared to the traditional methods of thermal-steam formation treatment, which involve steam injection from surface, well electrothermal devices can reduce energy losses and improve the quality of steam injected into the formation. For successful and efficient organization of oil production and rational development of high-viscosity oil fields using well electrothermal equipment, it is necessary to take into account the pattern of heat propagation, both in the reservoir and in the surrounding space, including the top and bottom. One of the main values characterizing this process is the heat conductivity λ of oil-bearing rocks. The article describes composition of typical oil-saturated sand soils, presents studies of heat and mass transfer in oil-saturated soils, reveals the effect of various parameters on the heat conductivity of a heterogeneous system, proposes a method for calculating the heat conductivity of oil-bearing soils by sequential reduction of a multicomponent system to a two-component system and proves the validity of the proposed approach by comparing acquired calculated dependencies and experimental data.
In Polish mining for backfilling the fly ash mixtures are used. Last time for fly ash mixtures preparation the saline water from mine have been used, to thanks to that the saline water missing the surface waters. Usage of saline water for fly ash mixture preparation causes the changes in energy looses during the flow in pipelines. The paper presents the results of energy looses measurement іn laboratory pipeline installation with diameter D =50 mm. The measurements have been performed for different fly ash – saline water proportions. Tested fly-ash from Siersza power plant has typical properties (grain size distribution curve, density) for ashes used for backfilling mixtures preparation. Increase of fluid (water) salinity modifies fluid viscosity. Brine in comparison with pure water retains as liquid with increased viscosity. Increased viscosity can influence on the mixture ash-brine properties for example causing flocculation effect. Also changeable salinity has an influence on proper determination of resistance (frictional) coefficient λ during mixtures flow in pipelines because it depends on Reynolds number which depends on liquid viscosity. Increase of fly-ash concentrations in fly-ash – brine mixtures cause increase of energy losses.
Analysis of the work hydrotransport systems in processing plants shows that the efficiency of this type transport does not match its technical capabilities: the high laboriousness involved in the operation of the equipment, high hydroabrasive wear of slurry pumps and pipelines, low working life pumps, high metal consumption and energy. The main reason for the lack of effectiveness of hydraulic transport is hydroabrasive wear impellers of slurry pumps, causing rising levels of vibra-tion pumps, reducing the pressure characteristics, general technical state of hydrotransport system and as a result - low pumps life, not exceeding 500 hours of continuous operation. In paper, it is shown that as a criterion of period normal operation slurry pump can be used coefficient of techni-cal state, the value of which is proportional to the relative head, degree of hydroabrasive wear of the impeller and time of continuous operating. The coefficient technical state of slurry pump can be represented as a function of current flow rate and the RMS value of vibration velocity. The re-sults of theoretical and experimental studies used to develop algorithms and techniques express-diagnosis and monitoring of slurry pumps in hydrotransport system, data which indicate the need for routine maintenance of pumping equipment.
The problem of decreasing power consumption by hydraulic transport systems remains to be the most important among other problems in the mining industry. The increase of solid material concentration in the volume of transported pulp leads to reduction of general pulp flow rate on the one hand and to increase of pressure losses and, accordingly, of a necessary head for over-coming hydraulic resistance on the other hand. The problem of minimizing power consumption in slurry transport is of particular relevance now when there is a tendency for hydraulic transport of highly-concentrated pulps and pastes to be widely used in the mining industry. The article shows that the energy intensity to a certain extent depends on the performance of hydraulic transport of solid materials, and this dependence is of extreme nature. At low concentra-tions of solid particles large volumes of recycled water have to be pumped to provide the neces-sary performance, which leads to consumption of large amounts of electricity. The increase оf concentration results in the decrease in the volumetric flow rate of the pulp and, accordingly, spe-cific power consumption of the process. The process of reducing energy consumption takes place up to a certain critical value of the concentration above which a further increase in the concentra-tion raises power consumption.
