Development Of Technological Parameters Research Articles

Құрамында бор бар силикохромды қолдану арқылы төмен көміртекті феррохромды балқыту процесін термодинамикалық модельдеу

The TERRA program for calculating multicomponent heterogeneous systems, based on the principle of maximum entropy, was used to study systems with a complex chemical composition, in which the task of numerical modeling is chemical and phase transformations play an important role. The effect of charge composition and temperature on the chemical and phase composition of melting products was studied, the degree of transition of charge elements into metal was determined, and optimal conditions for obtaining the alloy were found. The thermodynamic analysis of the ferrochromium production process showed that in order to approach the real process of low-carbon ferrochromium smelting, it is necessary to take into account the degree of silicon use by introducing oxygen into the working fluid to oxidize excess silicon according to the calculation. On the basis of the performed thermodynamic analysis, it is also shown that the choice of the process temperature (1750-1800°C and more) is associated with the kinetic conditions of melting, the melting temperature of the formed metal and slag. Therefore, it is expected that the presence of boron oxide, in addition to stabilizing slag from decomposition, will reduce its melting point, and the early appearance of the liquid phase due to low-temperature boron phases will ensure a shift in the reduction reactions of chromium with silicon to the low-temperature region. All these provisions will be implemented during high-temperature experimental work on the development of technological parameters.

TECHNOLOGY OF ENVIRONMENTALLY FRIENDLY FERMENTED MILK PRODUCT A NEW GENERATION FOR SPECIAL NUTRITION

This research work is devoted to the problems of using mare's milk in the development of a new variety of lactic acid products for special feeding of people in special working conditions.This article presents the results of experimental studies carried out on the development of technological parameters and modes, component composition and technological process of production of freeze-dried milk products of high biological value for special nutrition, produced on the basis of Mare's milk using new bio-facilities and plant ingredients. The purpose of the work is to develop and improve the technology of freeze - dried milk drink made on the basis of Mare's milk, intended for special nutrition. The scientific novelty of the project was the study of the quality indicators and technological properties of Mare's milk of the Pavlodar region. The yeast and its concentration, which provide the necessary probiotic properties of the lactic acid drink, are selected. For Special Nutrition, a new method has been developed to enrich the lactic acid product made from Mare's milk with a plant composition that forms the organoleptic properties and type. The component composition and technological process for the production of a fresh freeze-dried milk product of high nutritional and biological value for Special Nutrition has been developed and optimized. In the laboratory conditions of the Department of" Biotechnology", recipes of new types of lactic acid products made of Mare's milk for special nutrition were tested, and saal corsets of finished products were studied.

Combined anode processes in sulfuric acid solutions

Etching of carbon steel products in sulfuric acid solutions is, on the one hand, a common process in mechanical engineering and, on the other hand, harmful to the environment. As the concentration of H2SO4 decreases and the solution becomes saturated with Fe2SO4, the etching rate of the oxide film on the steel surface decreases. Therefore, while reducing the H2SO4 concentration to 25-30 g/l etching process is stopped, and replacing the etching solution. In this case, the concentration of Fe2SO4 reaches 400 g/l. During etching, two processes are observed: dissolution of oxides and dissolution of iron, which is located under the layer of oxides. These two processes can run simultaneously. The study of electrode processes in sulfuric acid solutions containing inorganic and organic impurities is the basis for the development of technological parameters for the regeneration of spent sulfate solutions. For the study used a little wear anode materials - platinum and lead oxide (IV). To determine the kinetic regularities of the anode process in selected anode materials, voltammetry was used with the construction of the obtained dependences in Tafel coordinates. The polarization dependences consist of two rectilinear sections with an inflection at logia ≈ -1,8 (ia, A · cm-2). The slope of the first section does not depend on the H2SO4 concentration and is 120 mV. The slope of the second section, for solutions with an H2SO4 concentration of 0,05 ... 0,37 mol/dm-3, is 60 mV, and for a concentration of 2,5 mol/dm-3 - 71 mV. A change in the concentration of sulfuric acid has practically no effect on the polarization of the anode. At a concentration of 5,0 mol·dm-3, in the area of high current density (≥ 1500 A∙m-2), the potential of the anode exceeds the PZCh for lead dioxide. This promotes the adsorption of sulfate ions on the surface of the composite anode and the onset of active oxygen formation. Under these conditions, the evolution of hydrogen peroxide is observed on the platinum anode. The polarization dependences consist of two straight sections with different slopes. For the entire range of sulfuric acid concentrations, at low current density portion is observed with a slope of 120 mV. Concentration of sulfuric acid at this site does not affect the kinetics of the process that corresponds to the literature data for platinum. The zero order in pH and independence from the concentration of sulfuric acid for this site indicates that the most probable mechanism of oxygen evolution is water rarefaction. The obtained values of the effective activation energy of the oxygen evolution process on the LOTC are close to the results obtained on platinum – 41,8 kJ mol-1 at Ea = 1,95 V. The value of the effective activation energy indicates the electrochemical nature of polarization, and its decrease with an increase in the anodic potential indicates a decrease in the strength of the bond between oxygen and the LOTC surface.

INFLUENCE OF TECHNOLOGICAL PARAMETERS OF THE ULTRAFILTRATION PROCESS OF CITRUS JUICES ON THEIR QUALITY

Fresh fruit juices contain organic acids and mineral substances (potassium, calcium, iron, copper, magnesium, phosphorus, manganese, molybdenum, boron, iodine), and their salts, large amounts of fiber, pectin and enzymes - complex substances, that contribute to the food processing and absorption of nutritional elements. Natural citrus juices contain essential vitamins and nutrients for the human body. Therefore, they represent a good opportunity for the treatment and prevention of various diseases. With the vitamins, taken through the juice, the human body becomes more resistant to viruses and infections, stressful situations and intense physical stress, and the body’s metabolism becomes normalized. Beverages, prepared from juices improve intestinal motility and thus contribute to improving the allocation of toxic substances and slags from the organism.
 The purpose of this work is the development of technological parameters of the ultrafiltration process to obtain natural juices which are sterile, resistant to precipitation and turbidity, and have a long shelf life. This paper examines the performance of the ultrafiltration process of citrus juices (lemon, tangerine, orange) and its dependence on the pressure and duration of the process, type and porosity of the membrane, the nature of the juice, and acidity. The juice composition was studied before and after ultrafiltration. It was established, that the productivity of the ultrafiltration process depends on: the duration of the process and this dependence is determined by the nature of the process: membrane type, in particular, filtration material and pressure: with an increase in membrane porosity and pressure, the productivity of the process, the volume of filtered juice, filtering speed and duration increases; the productivity of the ultrafiltration process, during the filtration both in dynamic and static mode, depends on the type and consistency of the juice: it increases with the increase of juice acidity. It was established: the general acidity (1.17%), density (1.038 g/cm3), the content of dry substances (9.9%), sugars (7.8%), including invert (7.2%), ash ( 0.26%), and vitamin C ( 20mg/ 100gr.), do not change in the course of ultrafiltration of tangerine juice. The viscosity, the content of carotenoids, cellulose and pectin decreases. The amino-acid structure practically does not change; hollow fibers detain only 6 - 8% of proteins and amino acids. For obtaining high-quality citrus juices, ultrafiltration should be carried out at a pressure 0.2MPa, on hollow fiber, in a dynamic, circulating mode.
 The juices obtained by ultrafiltration on hollow fibers (AP-2.0) are sterile, resistant to precipitation and turbidity, have significantly increased shelf lives, and they retain their organoleptic properties and nutritional values.

Optimization of the composition of fat systems of new generation

Fats are an integral part of human nutrition. The increased content of trans-isomers in their composition causes a number of cardiovascular diseases and metabolic disorders. A promising approach to solving the problem of minimizing the content of trans- isomers of fatty acid in the composition of food products is the creation of a new generation of fat systems – the oleogel, which is the subject of the presented research. As the dispersion medium of the oleogel, high-oleic sunflower oil is used, in contrast to the oil of traditional varieties, it is possible to obtain systems with enhanced oxidation resistance. The dispersed phase of these fat systems is beeswax, tripalmitin and monoacylglycerols. The choice of a complex of these components is based on their properties to create in oleogels a three-dimensional structure with desired thermomechanical characteristics. At present, there is not enough information about the dependence of the main characteristics of the oleogel on the ratio of ingredients of dispersed phase. In particular, one of the most problematic places in the oleogel technology is its thermal stability, which significantly affects the parameters of production, transportation, as well as storage conditions and periods. To solve this problem, the methodology of the response surface is used in the work. The determination of the unknown values of the parameter vector is carried out by applying regression analysis algorithms. The minimization of the deviation functional is performed by finding the appropriate combinations of experimental predictor series. As a result of research, a mathematical model is developed, which allows, based on data on the component composition of the oleogel, to predict its thermal stability. Reasonably rational mass fractions of the components of the dispersed phase of the oleogel: the content of beeswax is 3.27 wt. %; content of tripalmitin is 3.07 wt. % and the content of monoacylglycerol is 4.70 wt. %, at which the maximum value of the response function is reached. The results will serve as a scientific basis for the development of technological parameters of the industrial production of fat systems of the new generation, the conditions and terms of their storage and transportation.