Thermally activated chemical and metallurgical processes of lumping of fine-dispersed iron ore raw material during sintering are examined in the work. The following processes are included: moisture removal, ignition of coke fines and burn-off of carbonates, taking into account burning features of coke fines, fusion of grain charge, forming of agglomeration cake, creation of overhumidification area in sintering layer owing to condensation of water vapours in washout of heat-carrying gas. Parameters of sintering kinetics are obtained experimentally, other parameters characterizing layer shrinkage of sintering charge are presented. It was established that the temperature in the sintering area has substantial effect on shrinkage. The presented temperature relationship describes experimental data with sufficient precision. The values of power exchange coefficients in the drying area are examined. The criteria equations of heat and mass exchange are presented. The mathematical model using empiric material is proposed; it describes sintering kinetics for agglomeration charge, taking into account layer shrinkage and variation of head losses in technological areas of fusion and forming of ready agglomerate, what corresponds well with the experimental data. Multi-factor relationship between chemical and metallurgical processes (from one side) and heat and mass exchange in the sintering layer of agglomeration charge (from other side) is noted. Adequacy of mathematical models allows to use them for analysis of high-efficient conditions of agglomerate fabrication. The research was conducted under financial support of the Russian Foundation of Basic Research (RFFI within the framework of the scientific project No. 18-29-24094 МК and in accordance with the State assignment, the project No. FSWF-2020-0019.

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Arranging efficient operation of the fleet of induction motors (IM) in non-ferrous metallurgy is a large-scale technical and economic problem. In scientific aspect, the problem is being solved in the framework of two research lines: in developing criteria for the efficient operation of the branch IM fleet and towards the development of methods and tools for implementing the IM fleet efficient operation. The article presents the results of the authors’ work in the mentiond areas. The basis for developing criteria for efficient operation is modeling of current operational states, taking into account the IM operational aging processes. The existing methods and models are poorly focused on fixation of the changes caused by operational aging. There exists a demand for special methods and tools for modeling the IM operational conditions. A mathematical model based on Kolmogorov equations is one of these tools. The system graph and equations of the mathematical model are given. An example of a practical calculation of the no-failure operation probabilities at different rates of repair operations is given. It is stated that the offered mathematical model can serve as an instrument for developing criteria of the IM pool efficient operation. The system of periodic operational diagnostics is ment to be a key element in enhancement of the IM fleet operation efficiency. A topological method worked out for the problems of operational diagnostics is focused upon analyzing the dynamics of operational changes taking place in the IM vector space. The matrix of current deviations is a medium of objective and reliable information about the current IM technical condition. Matching the matrices of current and limiting deviations allows us to make several essential conclusions concerning the IM technical state. The reported study was funded under as a part of state assignment (project number, FSWF-2020–0019), as well as at the expense of RFBR (project number, 20-01-00283).