Hydrodynamics of cotton filtration drying

The work deals with the results of using the cotton fiber as the purest and most natural cellulose, as well as a raw material for the production of various chemical products. The necessity of cotton fiber preparation for its use in the chemical industry and expediency of its drying via a filtration method has been substantiated. The geometrical parameters of individual cotton villi, physical and mechanical characteristics of the layer were experimentally investigated. Under the action of pressure drop the effect of the cotton fiber layer height on the porosity, equivalent diameter, through which the heat agent is filtered, the specific surface area and the pressure loss were analytically determined. The experimental results regarding the pressure loss in a layer of cotton fiber during filtration drying are presented from the standpoint of the internal problem of hydrodynamics. The results of heat agent filtration through a cotton layer at different weights and heights of the layer are presented as a functional dependence ΔP = f(υ0), and changes in the layer porosity as ε = f(υ0). The generalization of the experimental data is represented as a dimensionless complex Eu = f(Re), and the dependence of the hydraulic resistance coefficient as a function of the Reynolds number ξ = f(Re). The results obtained in a dimensionless form make it possible to predict the energy costs for creating a pressure drop (under the same hydrodynamic conditions) when designing a new drying equipment.