Results of experimental study of the effect of initial maldistribution of structured packing irrigation on efficiency of binary mixture separation are presented in this article. The studies were carried out in the experimental distillation column with the diameter of 0.9 m using the R114 and R21 freon mixture. Experiments were performed on the structured Mellapak 350.Y packing of stainless steel 316L, containing 19 layers with the total height of 4.016 m at the ratio of mole liquid and vapor flow rates L/V 5 1 and 1.7, respectively, and the pressure in the upper part of the column p top 5 3 bars. Nonuniformity at the packing inlet was generated via the blocking of some holes in the liquid distributor. Here, we present some results on efficiency of mixture separation, pressure drop on the packing, distribution of local liquid flow rate under the packing over the cross-section and on the column wall within the range of vapor loading factor (0.69 < F v < 1.61 Pa 0.5 ), as well as experimental data on distribution of local concentration of the low-boiling component over the cross-section and along the height of the structured packing. It is found out that significant maldistribution of mixture concentration and liquid flow rate over the cross-section slightly changes along the height in the lower part of the column at a change in the degree of packing irrigation nonuniformity at the inlet. It is shown that efficiency of mixture separation depends considerably on the value of parameter L/V, vapor flow factor F v , and size of the zone underirrigated by liquid at the inlet. In the studied range of liquid and vapor flow rates, the relative pressure drop on the packing does not depend on the ratio of liquid and vapor flow rates L/V and degree of irrigation maldistribution.

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The paper present the results of experimental studies on dynamics of the film flow of cryogenic liquid over the complex surfaces: vertical plane and ribbed aluminum plates with horizontal wave microtexture. Experimental results were obtained at the flow of liquid nitrogen. According to high-speed video recording, in case of horizontal microstructure the wave dynamics influences considerably liquid redistribution in transverse direction. This is caused by the fact that liquid flows intensively at propagation of secondary waves along the channels of horizontal microstructure. According to results of experiments on the ribbed structured perforated aluminum surfaces with the horizontal microstructure with the use of highly wetting low-viscous liquids, the film flow character depends significantly on the irrigation rate. The direction and parameters of microstructure, position and diameter of holes effect significantly the zones of liquid spreading and its distribution over the surface of the ribbed structured plates, especially, within the range of low liquid flow rates.

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