Optimization of the process of mixing liquid-phase heterogeneous products by mathematical modeling

The main objective of the experimental study of all processes is the analysis, study and generalization of all available results. In accordance with the idea of a step search, the experiment was carried out in several stages. The number of stages and actions at each of them depended on the results of the previous stage and the ultimate goal of research. The ultimate goal of the study is to determine the optimal conditions for the process of mixing the liquid aggregates to obtain a homogeneous structure. Studies of the mixing process were carried out on an experimental setup created at the department. To process experimental studies, the STATISTICA 12 software package was used. To obtain the regression equation, the matrix data were processed using the Microsoft Excel 2010 software package. To optimize the process, the output parameters were converted to a dimensionless scale of desirability d. It was established that the desirability function D, which characterizes the adequacy of the obtained values, has an extremum in experiment 12 and is 0.733666. Based on the obtained data, the following parameters should be considered optimal when mixing liquid aggregates: the peripheral speed of the mixer shaft is within 4 m/s, while the mixing time is 8 s and the refrigerant concentration is 20%.

Effect of design and kinematic parameters on energy requirement in inclined screw mixer

Introduction. Rational parameters and modes of an inclined batch screw mixer are validated to achieve the lowest energyintensive feed mixing under observance of the zootechnical requirements for the feed quality on uneven mixing. The establishment of functional dependences between parameters and modes enables to design power-efficient equipment for the on-farm feed production.Materials and Methods.Experimental studies of the feed mixing were implemented on an inclined screw batch feed mixer. The experimental design included variation of four independent factors: mixer shaft speed, filling ratio of the mixing chamber, mixing time, and mixing chamber angle. Mixing irregularity and energy intensity of the process were taken as optimization criteria characterizing the mixing efficiency.Research Results.The optimization criteria versus the variability level factor, which are two-dimensional sections of the second-order response surfaces, are plotted. The rational values at mixing irregularity of less than 5% were as follows: mixer shaft speed was 27.5-36.5 min-1 , filling ratio of the mixing chamber was 0.43–0.51, mixing time was 3.0–4.2 min, mixing chamber angle was 22°–25°. At such parameter values, the mixing irregularity will be minimal, and it will be 4.10– 4.18%, and the process intensity is from 2.08 to 2.16 kW • h/t.Discussion and Conclusions.The dependences obtained as a result of the experimental studies allowed establishing the domain of rational design parameters and modes of an inclined batch screw mixer. The results obtained can be used in further studies under the development of initial requirements for the creation of new technical means with a gravitation effect of intensive mixing.

The effect of nanodispersed iron oxide additives on the formation of the density of carbon refractories

It was established that the addition of nanodispersed iron oxide pigment in an amount of 0,25‒0,50 % provides directional regulation of the chemisorption interaction of the binder and fller during mixing, contributing to an increase in the density of carbon refractories. It is shown that when introducing nano-additives into the carbon composition, it is necessary to adjust the mass of the binder in the direction of reducing its content. The principle of selecting the optimal binder content as a result of the plasticizing effect of nanodispersed iron oxide pigment at the maximum torque on the mixer shaft corresponds to a high level of expended mechanical energy and, accordingly, to intensify the mixing process and provides an increase in the sintering mass during fring.Ill.5. Ref. 14.

The Application of Harmonic Response Analysis in Different-Speed Mixer Design

The different-speed mixer is used in the rubber industry widely. The dynamic response of different-speed mixer shaft is very key. Some displacement and dynamic stress response values of different-speed mixer shaft frequency are obtained by using the finite element method, which gives the basic theory for further systematic dynamic analysis and the structure design of different-speed mixer shaft.