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2 Journal of New Technologies in Environmental Science

2 2018

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Force interaction of boiling dispersed emulsion particles

Klimov R. A.

Journal of New Technologies in Environmental Science

2018

Vol. 2, nr 2

60--67

In the industry lubricating fluids are widely used, mostly they reduce the wear of cutting tools and improve the quality of working surface, both in metal processin g technology and in other industries [1-3]. To achieve the greatest effect lubricating fluids must have a good surface wettability. This is achieved by introducing into the lubricating fluids the corresponding surface active agents (SAA), which also increase the cooling capacity of the medium. The adsorption phenomenon is based on the lubricating effect of various components of lubricating fluids. For liquids the adsorption is determined by the change in surface tension σ from the concentration of SAA. The desorption phenomena of SAA and particles aggregation of dispersed phase of lubricating fluids, which is an emulsion, determines sedimentation stability of emulsion and its further use [2, 4-7]. To reduce costs it is economically feasible to reuse spent lubricating fluids, but for this, their composition must be brought to normative, i.e. to clear it of mechanical impurities and also get the most stable structure for sedimentation, i.e. it is necessary to obtain the smallest size of the dispersed phase [5, 8-10]. Existing methods for calculating the processes of emulsification and homogenization of lubricating fluids are based on the dynamics of a single particle, which either boils with a sudden change in external parameters [4-6, 8, 11], or is subjected to the action of dynamic impact during the acceleration (deceleration) of flow, as well as is subjected to mechanical effects [7, 9, 11]. The examination of the dynamic interaction of two particles while boiling of light boiling component of the emulsion is given in [12]. Therefore, the study and development of the theoretical grounds of multitude drops breakup of discretely distributed phase is important for the determination of the optimal dispersion modes which results in a significant reduction in energy costs both during the grinding and crushing process, as well as reduction of the financial costs with repeated use of the same lubricating fluids, previously prepared before each cycle of use.

Destruction processes of oil films of emulsion environment

Klimov R. A., Pavlenko A. M.

Journal of New Technologies in Environmental Science

2018

Vol. 2, nr 2

75--83

Most of the methods aimed at studying the dynamics of growth of vapor bubbles which occur either in the liquid volume or on a superheated surface [1-3]. A peculiarity of emulsion media boiling is that the formation of a vapor phase occurs on the surface of liquid interface if one liquid (for example, oil) is a superficially active substance or in the emulsion there is a superficially active substance (in multicomponent emulsions), which is based on a decrease in the interfacial tension at the interface between the dispersive medium (water) and the dispersion phase (oil) [1, 3-6]. Experimental data [1, 3] indicate that the process of a new phase (vapor) formation is initiated by an internal thermal impact on the surface of the oil particles. Thus, for example, with a sudden pressure decay, the preheated emulsion will be in the supersaturation state of the thermolabile-water phase (the water is superheated against the saturation temperature at a given pressure), i.e. it will contain an excessive amount of heat [7-10]. This heat excess is expended on the work of vapor layer formation and further vaporization. The effect of oil films is ambiguous: on the one hand, when heated, they play the role of thermal resistance, thus, slowing down the heating process; on the other hand, they are the heat carriers which can be used for the formation and growth of the vapor phase and also they are superficially active substance, which contributes to achieving lower water supersaturation temperatures, i.e. early boiling [5]. The consideration of oil thermal effect plays an important role when regarding heat and mass transfer processes during the boiling of emulsion media. Theoretical description and analysis of heat and mass exchange processes in emulsions, associated with the presence of oil and oil films, allows us to study more in detail the process itself, as well as to offer optimal parameters and characteristics for the processes of obtaining and processing a fine emulsion.