Stanev R.Mitov I.Specht E.Herz F.2024-07-162024-07-162024-07-162024-07-162014-02-251314-74711314-7978SCOPUS_ID:84894058538https://rlib.uctm.edu/handle/123456789/1039Rotary kilns are aggregates for high temperature thermal treatment of a wide range of materials in a continuous technological process. This type of furnaces is used intensively in many industrial branches such as chemical, metallurgi-metallurgical, silicate, pharmaceutical, etc. In the metallurgy these units find application for heat treatment of bulk materials (e.g. oxide ores reduction, limestone calcination, sulphide copper stock drying, cleaning of metal swarfs from machine oil, etc). The present study enlarges the opportunities for a fast and reliable thickness determination of the separate zones of the solid disperse bed at rolling motion as the most widespread regime of its transverse transport. Data published in a previous work of the authors are used. They are obtained by a mathematical model established on the basis of regularities in the particles movement in a cylindrical rotary kiln, allowing determination of the total thickness of the layer of processed material and the active part of it, occupying the area immediately below the free surface of the bed. Approximation equations for prediction of the maximal values of the enumerated indicators depending on the inner diameter of the rotary kiln, its rotation speed, the filling degree of the drum with material, the dynamic angle of its repose and the particles diameter are proposed.enArticle