The article discusses the structure and principle of operation of an improved centrifugal unit for mixing bulk materials. A special feature of which is the ability to control mixing modes. Due to its design, the selection of a rational position of the bump makes it possible to provide such conditions for the impact interaction of particle flows, in which a high-quality homogeneous mixture of components is formed, the particles of which have different sizes, shapes and other parameters. To characterize the resulting mixture, the coefficient of heterogeneity was used, the conclusion of which is based on a probabilistic approach. A computational scheme of the rarefied flow formation process is given. An expression is derived for calculating the coefficient of heterogeneity when mixing bulk media, the particles of which have different sizes, shapes and other parameters. The research conducted in the article allows not only to predict the quality of the resulting mixture, but also to identify the factors that have the greatest impact on achieving the required uniformity.
Keywords: aggregate, bulk media, mixing, coefficient of heterogeneity, concentration, design scheme, particle size
The article discusses the main methods of carbon black granulation, and compares the results with an existing industrial installation. The granulation process is necessary to convert powdered carbon black into homogeneous granules in order to simplify its further transportation and use. Despite the wide variety of granulation methods, there are problems with the uniformity of granules, equipment wear, and the formation of stagnant zones. As a result of the experiments conducted on the laboratory granulator described in the article, photos of the results are provided. Each of the methods used has a description of stagnation zones, which allows us to conclude that the most efficient method is to convert powdered carbon black into granules.
Keywords: pelletizing, wear, granulator, rotor fingers, experiment, technique, carbon black
The article discusses the basic model of the formation of an emulsion layer on a rotating cylinder. Special attention is paid to the study of the influence of various parameters on the internal characteristics of the emulsion formation process. A mathematical description of the displacement layer is given and functional dependencies between the parameters characterizing the emulsion formation process are derived. Based on experimental data, the qualitative influence of "internal" and "external" factors on the formation of the emulsion layer has been studied. The result of the study were graphs, analyzing which the following conclusions can be drawn. An increase in the viscosity of the emulsion leads to a decrease in such parameters as the boundary of the fracture region of a more viscous liquid layer adjacent to the surface of the rotating cylinder, the viscosity of the emulsion in the transition layer, but there is an increase in the consumption of the emulsion. It is also established that the growth of the complex of "external" parameters leads to a decrease in all internal parameters during the formation of the emulsion. The research conducted in the article will help to take into account the obtained dependencies when calculating the operating and design parameters of devices.
Keywords: emulsion layer, viscosity, density, emulsion, rotating cylinder, liquid, emulsion composition