Hydraulic tests of a random helical packing element

A large number of different packing elements are applied in the chemical, oil refining, petrochemical, food and other industries for implementing heat-and-mass transfer processes in columns. The advantage of packed columns consists in their high efficiency, low flow resistance and stable operation. The most important requirements for packing elements include their high specific surface area, large free volume proportion, ease of manufacture and low material consumption. However, few available packing elements meet all of the aforementioned requirements. In this work, we developed a helical packing element for implementing heat-and-mass transfer processes in distillation, absorption and extraction columns, as well as in cooling towers, and carried out a series of respective hydraulic tests. The novel packing element is characterized by a simple design, implying coiling a metal strip into a helix. Such a shape excludes the contact with neighbouring elements, which prevents blocking of the packing surface and formation of stagnant zones. A specific feature of this design consists in the smooth surface of the element, which prevents the formation of drops and streams, thus reducing the mass transfer efficiency. The film-like flow through the packing element ensures high mass transfer characteristics with minimum entrainment, thus contributing to the reduction of flow resistance. On the basis of experimental data, empirical equations were obtained for calculating the flow resistance of dry and wet packing patterns. A comparative analysis of the developed packing element with Pall Rings and Inzhekhim-2000 is provided. It is shown that the developed helical packing element is characterized by a large surface area, significant free volume and low flow resistance. In addition, the simple design of the element significantly reduces its production costs.

mass transfer devices, helical metal packing, fractionating, absorption and ex-traction columns, design of packing elements, flow resistance

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