The process of preparing feed mixtures using additives is a biotechnical system with deterministic relationships with technological and technical and economic characteristics, and a group of input, disturbing, control and output factors, taking into account which it is necessary to determine the rational machine technology, the structure of operations and the corresponding technical solutions that are embedded in the design of the unit. To describe the processes of mixing compound feeds, the main attention is paid to the analysis of energy parameters, the establishment by experimental means of rational parameters and modes of operation of mixers of different types, the determination of the speed of the product movement in the mixer, its performance and evaluation of the quality of mixing. The development of a general theory of the choice of rational modes and design features of mixers is carried out by compiling a system of equations that describes the functional behavior of individual elements, as well as the influence of connections with external factors imposed on their functioning.