Известия Томского политехнического университета: Инжиниринг георесурсов (Oct 2016)
Experimental study of water-in-poil emulsion destabilization in nonuniform electric field
Abstract
The relevance of the research is caused by the necessity to improve the quality of oil preparation and processing, and decrease of water content in crude oil incoming the oil refining factories, as well as by the expediency of expanding the experimental data bank on regularities of water drops dynamics in heterogeneous media, such as water-in-oil emulsions, at their processing by non-uniform electric field. The data are rather relevant at the development of theoretical transfer models in mixtures. They are considerably valuable and useful in issues of improving the intensification techniques for phased and component separation of emulsion composition and at the development of technical decisions about perfection of devices for water-oil emulsion separation. The aim of the research is the experimental study of separate water drops deflection in oil from a vertical surface under the influence of non-uniform electric field at different intensities; and the analysis of water drops spatial distribution in emulsion at such processing. Research techniques: observation and analysis of motion of separate drops in salty and fresh water, and drops as a part of emulsion in the observational mesh affected by the electric field generated by flat electrodes of different linear dimensions. Results. It is shown that the relative deviation of a drop to a short electrode depends nonlinearly on the electric field strength in the center of area between electrodes. So the average relative deviation of drops makes 33-46 % at electric field strength of 2,61-2,93 кV/cm. The rebound of water drops to the opposite side from electrode is observed at the strength of 3,31 kV/cm and the deviation is reduced to 18 %. The rebound and a repeated attraction of drops up to electrode boundary is observed at the strength in 3,5 kV/cm. It gives maximum displacement of drops on the average on 57 %. The content of sodium chloride salts of 3,4 mole/liter concentration in flushing water affects negatively the effectiveness of processing with non-uniform electric field. It is ascertained that deflection of salty drops is at the average 42 % lower, than the one of drops in fresh water. It was determined as well that the drops are accumulated around a short electrode in three zones. The character of drop motion is different in each of them. It may be used for optimization of electrode form in the devices implementing processing in non-uniform electric field.
