Ключевые слова: гидроимпульсная обработка; кавитация; крекинг; нефть; роторный импульсный аппарат.Аннотация: Выполнен расчет энергии, необходимой для разрыва связи в углеводородных соединениях за счет энергии кавитационной обработки. Прове-дена оценка возможности крекинга нефти при гидроимпульсной кавитационной обработке в роторном импульсном аппарате. Экспериментально установлено, что гидродинамическое воздействие данного аппарата на нефть увеличивает выход светлых фракций при атмосферной перегонке на 5 %.Обозначения Е с -удельная энергия разрыва связи, кДж/моль; Е к -энергия схлопывания кавитационного пузырька, Дж; Е N -энергия, необходимая для образования пузырьков, Дж; Е 0 -энергия образования кавитационного пузырька, Дж; Е p -энергия разрыва связи химического соединения в одной молекуле, Дж; N -число молекул с разорванной связью; N A -число Авогадро; N м -число пузырьков, необходимых для разрыва связи в каждой из молекул 1 моля углеводородов; P -давление в жидкости, Па; P п -давление насыщенного пара (газа) в пузырьке, Па; R 0 -наибольший радиус кавитационного пузырька, м; R min -наименьший радиус кавитационно-го пузырька, м; t -температура, °C; V -доля фракции в общем объеме, %; σ -поверхностное натяжение, Н/м. В настоящее время многие исследователи уделяют особое внимание методам интенсивной физической обработки нефти и нефтепродуктов в целях увеличения выхода светлых фракций при атмосферной перегонке. Для решения данной зада-чи применяются различные энергетические воздействия в импульсной форме: механические, гидродинамические, электрические, магнитные [1 -18].Гидроимпульсная обработка нефти реализуется за счет генерирования в об-рабатываемой жидкости пульсаций давления и скорости потока. При движении потока жидкости через канал с периодически изменяющейся площадью проход-ного сечения потери энергии на создание импульсов давления в жидкости мини-

Parameters of radial types of pulsed rotary equipment for the treatment of liquids are examined, and computational relationships and analysis criteria are described. Results are presented for experimental investigations confirming the adequacy of the proposed computational procedure.Pulsed rotary equipment (PRE) is used to produce stable highly disperse emulsions and suspensions, intensify the solution and extraction of substances, change the physicochemical parameters of liquids, break down molecular compounds by multifactorial pulsed action on liquid-liquid, liquid-solid, and gas-liquid systems, including: 1) mechanical action on particles of a heterogeneous medium (impact, shear, and pulverizing loads and contacts with working parts of PRE);2) hydrodynamic effect (large shear stresses in a liquid, developed turbulence, and pressure and velocity pulsations in a liquid flow); and3) hydroacoustic effect on a liquid (small-scale pressure pulsations, heavy cavitation, shock waves, and nonlinear acoustic effects) [1-7].One of the basic design features of PRE is the use of a rotor and stator in the form of disks (axial type of PRE), or cylinders (radial type of PRE). In the first case, channels for the passage of liquid are coaxial with the axis of rotation of the rotor, and in the second, they are located in the cylindrical walls of the rotor and stator, and the flow of liquid takes place in the radial direction. The development of centrifugal forces acting on the liquid within the recess of the rotor is an advantage of radial over axial types of PRE. Figure 1 shows a typical schematic of a radial type of PRE. The liquid to be treated is delivered under pressure, or gravity flow through an inlet pipe into the rotor recess, proceeds through the channels of the rotor and stator, and effective chamber formed by the housing and cover, and exits from the apparatus via a discharge pipe.During rotation, the rotor channels become periodically aligned with the stator channels. If the rotor channels are covered by the stator wall, the pressure increases in the rotor recess. When a rotor channel is aligned with a stator channel, the pressure is reduced for a short time interval, as a result of which a pulse of excess pressure develops in the stator channel. A short-lived pulse of reduced ("negative") pressure develops behind it, since alignment of the rotor and stator channels has been concluded, and the feed of liquid into the stator channel is accomplished only by a "transit" flow from the radial gap between the rotor and stator. The volume of liquid in the stator channel tends to exit from the latter, and tensile stresses are created in the liquid under inertial forces; this will result in cavitation. Cavitation bubbles will grow as the pressure drops to that of the saturated vapors of the liquid being treated at a given temperature, and collapse or surge into the stator channel as the pressure increases.In analyzing PRE, it is necessary to isolate the following two problems: analysis and design of universal equipment inten...

A method is described for altering the physicochemical parameters of petroleum products by inducing a multifactorial effect in a pulsed rotor unit. Experimental data are cited for the pulsed multifactorial energy treatment of atmospheric resids produced by various refineries; these data confirm the effectiveness of the proposed method for improving the quality of hydrocarbon fuels.Various methods and procedures that make it possible to vary the physicochemical parameters of petroleum fuels, and increase the yield of light petroleum derivatives during the refining of crude are currently under development. The kinetics of processes of crude and petroleum-derivative refining can be influenced by chemical substances (catalysts, surfaceactive substances -SAS, additives, etc.) and physical fields (thermal, cavitation, electromagnetic, etc.). The radius of the nucleus and the thickness of the adsorption-solvate layer -the complex base unit, which is a component of a disperse petroleum system -is altered as a result of such interference.The influence exerted by chemical substances on crude and its resids is a complex regulated process, which results in accelerated wear of production equipment. Today, many researchers are focusing their attention on methods of vigorous treatment of crude and petroleum derivatives to increase the yield of light fractions, lower the sulfur content, reduce the viscosity, etc.The method of a pulsed energy effect of acoustic waves and cavitation [1-3], which alter the hydrodynamics and dispersion stability of liquid media, is the basis of technologies utilizing the cavitation effect on crude and petroleum derivatives; this will exert different influences on process mechanisms -markedly intensifying one (destruction) and abruptly slowing others (coking).An energy effect on the crude and petroleum derivatives makes it possible to increase the yield of highly volatile fractions resulting from their distillation. Using a pulsed energy effect, it is possible to derive 20-30% of naphtha, 40-50% of diesel fuel, and 20-30% of atmospheric resid, asphalt, and other heavy commercial products from heavy crude. Cavitation treatment will accelerate diffusion of the crude in wax cages and intensify its breakdown. Acceleration of wax dissolution occurs due to intensification of the agitation of crude on the crude-wax boundary, and the effects of pressure pulses, which disperse the wax particles. Cavitation ruptures the bonds between individual parts of the molecules, and influences the change in structural viscosity. Under long-term vigorous cavitation, the C-C bonds are broken in the wax molecules, as a result of which the physicochemical parameters are altered (the molecular mass, crystallization temperature, etc.), and the properties of the petroleum derivatives (viscosity, density, flash point) are lowered [4][5][6][7][8][9].To rupture the bonds in the molecules of the hydrocarbon compounds in such multicomponent systems as crude and petroleum derivatives, it is necessary to provide a multifactorial energ...

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Аннотация: Выполнен анализ результатов экспериментальных исследований по оценке возможности микрокрекинга легкой и тяжелой нефти при гидроимпульсной кавитационной обработке в роторном импульсном аппарате (РИА). Экспериментально установлено, что гидроимпульсное кавитационное воздействие РИА на нефть увеличивает выход дистиллята при перегонке под атмосферным давлением.