Search

Studies have been carried out on the purification of biogas from sulfur compounds, carbon dioxide and water vapor for subsequent use in micronizer burners. The possibility of bringing it to the parameters of natural gas of the following composition: methane (CH4) – 85 % vol., carbon dioxide СО2 – 11 % vol., water vapor – 9 mg/m3, hydrogen sulfide H2S - 20 mg/m3 with minimal energy costs for its preparation is demonstrated. The basic relationships are obtained for assessing the design and technological parameters of the infrared radiation burners operation. Experimental studies of the flame stability limits on perforated ceramic nozzles have shown that flashback through them is possible when the thermal power is increased to a certain critical value. In this case, the thermal power depends on the type of gas and the air content in the combustible mixture. The heat balance equations have been derived to optimize the designs and operation modes of infrared radiation burners. The design of 40 gas burners was improved by changing the geometric dimensions and shape for a uniform distribution of biogas supplied and sustainable combustion over the entire area of the burner. It was established that the temperature of the heating surface of the GIK-8 burner on gas mixtures with a CO2 content of 18-34 % is 900-950 ° C, which does not differ from the nominal temperature when operating on natural gas. The infrared heating system was modernized, adapted for burning purified biogas with methane content up to 98 %, in particular, the biomethane feed and control system, the additional biogas input system, and the automatic burner control system were improved.

The developed simulation model allows computer experiments on mixing components in which the parameters of the components of the mixture or mixer are changed, the nature of the influence of the parameter is established and recommendations for choosing the optimal values of the parameter are given. The model of the mixing process takes into account the size, shape and rheological properties of the components of the mixture, as well as the interaction of the bulk material with the working surfaces of the mixer (blades, blade struts, shafts, housing). The simulation mathematical model of the mixer has a high spatial resolution for the correct reproduction of the interaction of particles in the mixing process. In the framework of the finite element approximation, the bulk material is represented as a set of elements. The particle dynamics method was used to model the mechanical behavior of the mixture. Modeling is performed in three-dimensional Cartesian space. The state of each element is defined by six variables: the coordinates of its center and the velocity components. The solution of this system of differential equations of the second order are the functions that determine the trajectories of motion of the elements and allow to evaluate the efficiency of the mixing process. To solve differential equations of this kind, the second – order numerical method-Runge-Kutta is used. A computer program in the Object Pascal language in the Borland Delphi 7 integrated programming environment has been developed to implement the calculation according to the above formulas and to make it easier to conduct a series of computer experiments. The developed mathematical model of the process of mixing of bulk components allows to choose rational technological modes of mixing, which makes it possible to increase the homogeneity of mixing up to 98 %, and to calculate the kinematic mode of the mixing process in the mixer by creating a "quasi-weight" hydrodynamic mixing mode and a significant acceleration of the mixing process.

As a result of the conducted experimental studies, the main kinetic regularities of the steaming process under investigation were determined and the choice of rational modes of grain moisture-heat treatment was validated: steaming of barley and wheat with steam to a moisture content of 19 % at a steam consumption of 100–180 kg/h and a pressure of 0.20–0.35 MPa for 10–12 minutes, and corn – for 15–16 minutes. These developed modes provide the best conditions for the thermomechanical destruction of the protein-carbohydrate complex in order to increase its availability to digestive enzymes and increase the digestibility of starch, do not reduce the digestibility of protein and improve sanitary condition. A method of engineering calculation was developed, which formed the basis for the creation of an original design of conditioner steamer. The performed constructive calculation included the calculation of the mixer-humidifier, the calculation of the jet nozzle and the determination of the dispersed characteristics during steam atomization, as well as the thermal calculation of the conditioner steamer, which made it possible to determine the steam consumption and determine the rational heating temperature of the grains and their moisture content. A distinctive feature of the conditioner steamer is a higher productivity due to the significant acceleration of diffusion process of moisture into grains; the possibility of improving the quality by increasing the degree of starch gelatinization due to selected technological steaming modes.

At present, work has been activated to develop and introduce healthy food products, reduce unit costs for the production of fat-and-oil products. In view of the multicomponent nature of many emulsion products and the difference in their aggregate state, there is a need to improve the design of equipment for production. The main indicators of the mixing process are the intensity and efficiency, as well as the energy consumption for the process. In the production of emulsions, the mixing efficiency can be characterized by the size of the forming particles of the dispersed phase, and the intensity - by the time of achieving the process goal - of a homogeneous structure with a multicomponent product, with minimal energy costs. In order to determine the time to achieve the result of the process, a dimensionless concentration can be used as an estimate. The effectiveness of mixing was evaluated by the dispersion of the emulsion. The investigations were carried out on a microscope "Micrometer 3" with an increase of 400 times. The average diameter of the emulsified particles was d = 5 10E-5 m, and the specific surface area of the emulsions was S = 1.2 10E5 1 / m. The proposed method for calculating the intensity and determining the mixing efficiency can be used to calculate the mixing of multicomponent emulsions of chemical and food products. The use of the proposed emulsion design makes it possible to optimize the process of thermomechanical action on raw materials, different in their physico-mechanical properties, by ensuring the maintenance of a given temperature regime in each of the emulsion chambers and the rational nature of the product movement; expand the scope of application due to the achieved universalization of the mixing mechanisms taking into account the physico-mechanical properties of the initial components; to obtain spreads balanced by fatty acid composition, consisting of a mixture of various components, by solving the problem of uniform distribution of the components of the mixture and the most rational temperature effect on them.

The mathematical model describing distribution of fields of temperatures and moisture contents in a particle of a squared beet press at convective drying is given. As the initial equations the differential equations of material and thermal balances in which transfer of warmth and weight is caused by phase transformations have been accepted. The algorithm of the numerical solution of a non-stationary regional problem of heat conductivity with variable heat and mass transfer coefficients of the dried-up product, boundary and entry conditions and also phase transition with mobile limit of the section of phases is developed for the solution of mathematical model. At the same time the initial system of the equations is given to a dimensionless look. For the solution of a problem of non-stationary heat conductivity the zone method of calculation of temperature fields when drying a beet press is used. Process of drying broke into some time intervals. Within each interval geometrical form of a particle, its density, heatphysical and mass-exchanged characteristics; initial distribution of temperature and moisture content on particle volume and also density of a mass and thermal stream with the evaporated moisture are constant. The zone method of the solution of a problem of the non-stationary three-dimensional equation of heat conductivity for a parallelepiped taking into account internal sources of warmth has been checked on experimental data of stationary drying of a beet press with use of basic data. For realization of a zone method dependences of change of the linear size of a particle of a beet press on spatial coordinate x and its moisture content in the course of drying are received. At constant values of moisture content and the sizes of the party of the dried-up particle on each step the method of a machine experiment has found the current values of coefficient of phase transformation on condition of the maximum rapprochement of settlement and experimental data. The offered method of calculation of distribution of temperature fields and fields moisture containing at convective drying of a beet press in the variable modes with use of the three-dimensional equation of heat conductivity has shown compliance of settlement and experimental data with a margin error of modeling 8–10%. The received results have been used when developing a two-level way of drying of a beet press. The offered method of calculation of two-level drying of a beet press has allowed to provide the maximum kinetic compliance at implementation of temperature conditions in the field of admissible technological properties of the dried-up product.

The description of the technological scheme of the stock-preparation shop, press shop and cleaning of worm-press oil at Chernozemye LLC, with an analysis of the main types of technological equipment operation and evaluation of problematic production sites is given. It has been established that during hulling and following separation into fractions in separators and sifts, favorable conditions are created for oiling the husks by contacting it while passing through a sieve together with a high-oiled crushed kernel and oilseed dust. To reduce the oil content of husks in the scheme, it is recommended to use hydrocyclones that direct the husk for the subsequent separation of the particles of the kernel and oil dust carried along with the husk. It was also revealed that the greatest content of waxes and waxlike substances in the oil, which significantly affect the transparency of commercial sunflower oil, is contained in the husks lipids, which partially pass into the oil during the processing of seeds. The content of waxes in oils is the higher, the more husk is contained in the kernel, and the higher the temperature of the pulp entering the pressing. In this case, the ratio of oleic and linoleic acids in low-oil varieties is 1:1, in high-oil varieties is 1:3. The heterogeneity of the grinding of the oil seed meal, resulting from the hulling of seeds, makes it difficult to uniformly moisten, warm and dry the pulp in the conditioner. The structure of the finished pulp is influenced by the primary structure of the oil seed meal, obtained during the process of grinding the seeds. The intensive coloring of the pulp, oil cake and ground oil-cake during the drying of oil seed meal is due to the high temperature (above 100 °C) in the conditioner, which leads to an intensive course of the sugar-amino reactions, an increase in the total content of nitrogen and phosphorus. And this changes color and increases raw materials losses.

The technological process of cereals production used in the production of feed stuff, which includes the following basic steps: grain moistening; binning of moistened grain for redistribution of moisture in the bulk of kernel; steaming of moistened grain; rolling of steamed grain; drying and cooling of flakes – is developed. In the production of flakes from scoured barley and oat grain before feeding to the rolling line film removal from the grain of these crops and the separation of the husks is carried out by one the existing methods: the method of grinding, followed by sifting and eventilation of films from tail fractions or a method of peeling on special machines with a separation of films. Wet-heat treatment of grain, followed by rolling helps to improve taste and palatability of feed, improves the nutritional value of carbohydrate and protein complexes, reduces the exertion of the body to digest food nutrients, allows to inactivate antinutritional substances and free the grain from the pathogenic and other microorganisms. In the duration of rolling process splitting of complex carbohydrates occurs, starch loses its original structure and is easier exposed to enzymes. The dried and cooled flakes have satisfactory flowability, do not set up. Humidity of flakes is not more than 14%, the temperature is not more than 10 °C above the ambient temperature, bulk density is 350–400 kg/m3. Developed set of equipment allows producing cereal flakes, the use of which in feed stuff and rations of young cattle and pigs increases the productivity of animals by 15–20% while reducing feed costs by 12–15%. Cereal flakes are used in the manufacture of complete feed for piglets (pigs at the age of 10 to 60 days), feed concentrates for pigs under the age of 4 months, the calves under the age of 115 days, high-producing cows, sporting and trained horses and lactating mares.

Researches of thermal and rheological properties of cream- and vegetable spread are necessary for the scientific substantiation of their obtaining process, namely mixing and crystallization processes. As the object of research, we chose a cream- and vegetable spread, with the following composition: peanut butter 10%; wheat germ oil 10%; linseed oil 20%; butter 59.8%; emulsifier 0.2%. With the data obtained in the course of research of the rheological properties of cream- and vegetable spread, one can subsequently generate recommendations for optimization of technological modes of production. In particular, one can solve problems of intensification of hydro-mechanical and thermal processes by carrying them out at such a temperature and speed when the maximum preservation of the produced product structure will be achieved. Determination of thermal characteristics was carried out in the apparatus for the study of thermal and rheological properties of viscoelastic liquids Coesfeld RT-1394H. Rheological researches of cream- and vegetable spread were carried out on a series of viscometers SV-10 and PB-8m. The graphs of spread dynamic viscosity dependence on the temperature, and the dependence of the effective viscosity of the spread and vegetable oils on the shear rate were built according to experimental data. The data obtained is rational to choose the equipment for processing and production of cream- and vegetable spread, to simulate processes taking place in the production process, to solve problems of intensification of thermal and hydro-mechanical processes reasonably, by conducting the production process at temperatures that do not cause the destruction of the product structure.