Видання № 1 (12) – 2014

Сортировать по умолчанию названию
  • ДОСЛІДЖЕННЯ ПАРАМЕТРИЧНОЇ СХЕМИ СКЛОВАРНОЇ ПЕЧІ

    Досліджено параметричну схему скловарної печі, розглянуті усі вхідні, вихідні сигнали, керовані й некеровані збурення. Параметричну схему спрощено до одного вихідного параметра.


    In this the work considered and investigated parametric diagram glass furnace. Completely considered all input, output signals, managed and controlled disturbance. Parametric diagram shows the object is a complex number base and utility lines. It is necessary to simplify the scheme for the formation of the task of the study.

    The temperature in the area of lighting the gas mixture the main parameters of the furnace, as it directly affects the quality of the glass, which in turn affects the quality of the finished product. The object is the impact of a controlled perturbation – air temperature at the inlet. There is a temperature control of gas-air mixture in the furnace area lighting one contour closed system with a single input signal, control signal and controlled disturbance.

    The main source parameter furnace as automation object performs the temperature of the glass. Parametric circuit obtained after simplifications can be decomposed into two. The first release will be performing temperature glass, measuring thermocouples happens to them, and the second – the temperature in the area of lighting the gas mixture, the measurement takes place thermocouples.

    Temperature gas-air mixture affects the temperature of the glass and the system is part of the control system of feeding fuel to the furnace burners as one of the paths, and depending on the task, can be considered as a separate system. Accordingly, the total system output parameter temperature serving glass.

    All inputs, outputs and disturbances will be used in modeling, under a parametric circuit designed furnace. When creating a mathematical model and check its adequacy, in addition to an analysis of existing models bathrooms, regenerative glass furnaces, consider the data and design features glass factories.

    As a result of research on parametric scheme furnace was obtained parametric simplified diagram of one output parameter – temperature glass and three input parameters: fuel gas and air in the combustion process, the temperature of the gas.


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  • ДИСКРЕТНА СИСТЕМА АВТОМАТИЧНОГО КЕРУВАННЯ НАПІРНИМ ЯЩИКОМ ВІДКРИТОГО ТИПУ

    Досліджено параметричну схему скловарної печі, розглянуті усі вхідні, вихідні сигнали, керовані й некеровані збурення. Параметричну схему спрощено до одного вихідного параметра.


    In this the work considered and investigated parametric diagram glass furnace. Completely considered all input, output signals, managed and controlled disturbance. Parametric diagram shows the object is a complex number base and utility lines. It is necessary to simplify the scheme for the formation of the task of the study.

    The temperature in the area of lighting the gas mixture the main parameters of the furnace, as it directly affects the quality of the glass, which in turn affects the quality of the finished product. The object is the impact of a controlled perturbation – air temperature at the inlet. There is a temperature control of gas-air mixture in the furnace area lighting one contour closed system with a single input signal, control signal and controlled disturbance.

    The main source parameter furnace as automation object performs the temperature of the glass. Parametric circuit obtained after simplifications can be decomposed into two. The first release will be performing temperature glass, measuring thermocouples happens to them, and the second – the temperature in the area of lighting the gas mixture, the measurement takes place thermocouples.

    Temperature gas-air mixture affects the temperature of the glass and the system is part of the control system of feeding fuel to the furnace burners as one of the paths, and depending on the task, can be considered as a separate system. Accordingly, the total system output parameter temperature serving glass.

    All inputs, outputs and disturbances will be used in modeling, under a parametric circuit designed furnace. When creating a mathematical model and check its adequacy, in addition to an analysis of existing models bathrooms, regenerative glass furnaces, consider the data and design features glass factories.

    As a result of research on parametric scheme furnace was obtained parametric simplified diagram of one output parameter – temperature glass and three input parameters: fuel gas and air in the combustion process, the temperature of the gas.


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  • ДИСКРЕТИЗАЦІЯ ПАРАМЕТРІВ У ЧАСІ ПІД ЧАС СТАТИСТИЧНИХ ДОСЛІДЖЕНЬ

    Розглянуті алгоритми, що дозволяють визначити оптимальний відносно вибраного критерію час дискретизації опитування технологічних параметрів, що забезпечує достатню точність визначення цього параметра, попри дискретність звертання до вимірювальних пристроїв.


    The classification of objects of statistical study is proposed, depending on the ratio of the factors influencing the choice of resampling. The recommendations for their use are given, which allow plan reasonably experiment and improve the efficiency of research.


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  • ОПТИМАЛЬНЕ КЕРУВАННЯ РЕЖИМОМ ПУСКУ АВТОКЛАВА У ВИРОБНИЦТВІ АЗОТНОЇ КИСЛОТИ

    Запропоновано алгоритм оптимального керування режимом пуску автоклаву з використанням нелінійної математичної моделі, методу штрафів і градієнтної процедури.


    The algorithm of optimal control of autoclave start mode in the production of nitric acid is proposed. By optimality criterion is selected minimum time-autoclave at preset mode with the restriction on the concentration of nitric acid. End time start mode is entered on the terminal part of the cost function. The method of penalties and a gradient procedure is used to solve the problem. The applied algorithm is allowed to bring an autoclave at a given technological regime.


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  • ПЕРЕДАТНІ ФУНКЦІЇ ТА ЧАСТОТНІ ХАРАКТЕРИСТИКИ ЦИЛІНДРИЧНОЇ ТЕПЛОАКУМУЛЮЮЧОЇ СТІНКИ: НОВІ ВАРІАНТИ

    Наведено передатні функції й частотні характеристики циліндричної теплоакумулюючої стінки як об’єкта з розподіленими параметрами залежно від межових умов на зовнішній і внутрішній поверхнях. Отримані результати можуть бути використані для синтезу систем керування.


    Almost all real objects control in chemical, food, metallurgical, oil and other industries, in fact in the entire field of human activity are objects with distributed parameters.

    From mathematical modeling point of view a lot of plants in different industries can be considered as cylindrical heat storage walls with distributed parameters. Selected research path based on the following considerations: consider only heat objects with distributed parameters as the most common in the industry; Mathematical model objects with distributed parameters obtained in the form of the transfer function as the most suitable for further research in terms of analysis and synthesis of control systems using existing software. The aim of this study was to receive transfer functions and frequency responses as mathematical models of above mentioned plants. To solve this problem the main equation of heat conductivity was put in basis. In addition three kinds of boundary conditions on external and internal wall surfaces were taken into account. Different combinations of boundary conditions on external and internal wall surfaces result in different kinds of transfer functions and frequency responses. These functions are transcendental and perhaps must be simplified for practical using. It was proposed few nontrivial ways in order to calculate frequency responses of cylindrical heat storage walls. To implement this calculation it is necessary to have available a subroutine for computing certain functions. If necessary, these routines can create their own with the above formulas. You can also use the tables of the functions, forming the basis of their structure interpolation (polynomial, cubic splines or B-splines). But most appropriate looks above numerical integration of differential equations with appropriate boundary conditions on single stepped input signal with zero initial conditions.

    Obtained results can be used for researching of plants, which can be considered as cylindrical heat storage walls with distributed parameters, and for control system synthesis.


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  • МАТЕМАТИЧЕСКАЯ МОДЕЛЬ ПРОГРЕВА БУМАЖНОГО ПОЛОТНА В СУШИЛЬНОЙ ЧАСТИ БУМАГОДЕЛАТЕЛЬНОЙ МАШИНЫ

    Рассмотрены вопросы тепло- и массопереноса на первом этапе сушки бумажного полотна, в частности тепло- и массообмен между сушильным цилиндром и бумажным полотном, окружающей средой и бумажным полотном, а также перенос теплоты и влаги в материале. Проанализирована физика процессов, получены уравнения для расчета температуры и влажности крайнего и центрального слоя бумаги при прохождении через сушильный цилиндр и на участке свободного хода.


    Drying section of a paper machine is the final stage of dehydration of the paper web and largely affects on many indicators of quality of the finished product. All drying process consists of three successive stages of passing: heating a material, portion of constant drying rate and decreasing drying rate. The analysis of the first stage of drying, heating process is presented in this work. Each part of the process which can be separated into such components: transfer of heat and moisture on the contact portion of the paper web with the drying cylinder, on a plot of a freewheeling and transferring heat and moisture inside the material. For each of them was created a mathematical model wish allows to calculate the temperature and humidity of the paper web. For accurate simulation was made a detail analyze of heat transfer from the drying cylinder to a paper web. Due to the heterogeneity of the temperature field inside the material, the heat transfer is divided into two parts, from the drying cylinder to the material surface and from the surface to the central layer. On the site of a freewheeling, most attention is given to processes of moisture transport from the center of the paper web into the environment through the material and drying the cloth.

    As the dryer section consists of a series of repeated cycles, in the work was given the generalized mathematical model that calculates the parameters of paper at the end of each cycle under certain initial parameters of the paper drying cylinder and the ambient air.

    The mathematic model, presented in this work, is the first part of the model that describes overall process of drying a paper web on a paper machine. Supplemented by models for areas of constant and falling drying rate, they allow calculating the parameters of the product at any point in its location in the dryer section. On the basis of the general model will be possible to build an optimal automatic control system. Such system will solve the actual task of reducing the cost of the paper web drying process with maintaining the specified quality parameters.


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  • МОДЕЛЮВАННЯ РЕАКЦІЙНИХ ТРУБ ПЕЧІ ТРУБЧАСТОГО ТИПУ В КОНВЕРСІЇ МЕТАНУ

    Проаналізовано математичну модель реакційної труби печі трубчастого типу – основного апарата на першій стадії конверсії метану. Одержано систему диференціальних рівнянь для подальших досліджень.


    The most famous technologies of making hydrogen are based on chemical and thermal processes also on electrolysis of water. However, they major shortcomings as the use of high potential energy to the costs of fossil fuels and therefore significant pollution. The disadvantage of electrolysis of water is a significant level of power consumption. Electrolytic hydrogen is the available, but more expensive product. Today, the world's largest distribution obtained technology of developing hydrogen or a mixture of hydrogen and other gases by steam reforming of natural gas – methane. But almost half of the initial volume of gas consumed in carrying out endothermic steam reforming process. So the world is making an intensive search for such technologies that produces hydrogen, which would meet the requirements of economic and energy efficiency and environmental safety.

    The process of steam reforming of hydrocarbon compounds designed to produce hydrogen technology and other process gases by high-temperature catalytic reforming in the cycle of production of synthesis gas. The process of conversion is one of the most important stages of the process of obtaining gas in ammonia synthesis loop. Despite the complexity of hardware design, steam catalytic conversion of methane in the furnace tube is currently the most economical way to get the process gas and hydrogen.

    Therefore, to improve it is relevant and necessary scientific and technical challenge. Given that the full-scale study of the process of conversion is expensive, very difficult and dangerous. To solve the problems of design of process equipment, synthesis and study of control systems, simulators technical personnel, the challenge of obtaining the mathematical model of the process object that will best reproduce the properties of real prototype to a wide range of operation. However, creating of a model is based on a compromise between the complexity of the mathematical tools and depth of simplifications and neglects. Today we know a few tube type furnace models, including regression models, which are widely used because of its ability to approximate analytical relationship between input, output variables for multiple passively or actively conducted experiments, and mathematical models are based on the theory of fuzzy logic and fuzzy set theory. The general scientific problem is that with most of them do not allow modeling the dynamics of the process and, therefore, not part of the unsolved scientific problem is that it makes it impossible to optimize dynamic processes.


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  • МОДЕЛЮВАННЯ НАСАДКОВОГО АБСОРБЕРА У ПРОЦЕСІ ОДЕРЖАННЯ АЦЕТИЛЕНУ З РЕАКЦІЙНИХ ГАЗІВ

    Розглянуто та проаналізовано математичну модель насадкового абсорбера у процесі виготовлення ацетилену з реакційних газів, у якому проходить основний процес насичення ацетилену. Одержано систему диференційних рівнянь для подальших досліджень.


    There are many different ways to produce acetylene. Among them, such as manufacturing out of calcium carbide, pyrolysis of hydrocarbons and gas separation from gases which consist acetylene. All of these technologies are based on chemical or mass transfer processes, etc. However, they are energy consuming and pour on the environment. Production using pyrolysis spends a lot of heat in the process of selection of the product, so there is an opportunity to significantly improve the technical and economic performance using plasma process, but these measures have not been ever brought in real life. If we consider the process of production of reactive acetylene gas using dimethylformamide, it is certain that a large amount of dimethylformamide can spend to achieve the level of concentration in the reaction of acetylene gas. Only the following reasons, the quality of the incoming gas mixture can vary significantly. In this regard, we seek such factors by which the process will be more meet feasibility requirements and reduce the impact on the environment.

    The manufacture of acetylene gas from the reaction gases is designed to produce high quality acetylene by mass transfer processes taking place in absorbers.

    The process of mass transfer in the absorber is one of the most important steps in being saturated with acetylene production cycle. Production of acetylene from the reaction gas is the most economical way of obtaining acetylene because all unused products in the process of returning to a pure storage, where they can be used again in the process. The research on real objects is expensive, very difficult and dangerous, so this improvement is relevant and necessary.

    To solve the problems of design of process equipment, synthesis and study of control systems the challenge of obtaining the mathematical model of the process object that best reproduce the properties of real prototype to a wide range of operation. For this purpose, a mathematical model is needed, which would most closely corresponds to the actual and also based on the complexity of the device and the usage of simplifications, which could be neglected .

    Today we know a few models of packed absorbers, including regression models and mathematical models are based on the theory of fuzzy logic and fuzzy set theory. However, most of them do not allow simulating the dynamics of the process, and thus make it impossible to optimize dynamic processes.


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  • ЭФФЕКТИВНОСТЬ ИСПОЛЬЗОВАНИЯ РАПСОВОЙ ЦЕЛЛЮЛОЗЫ

    Исследовано влияние пероксида водорода на волокнистые полуфабрикаты, полученные из соломы рапса нейтрально-сульфитным способом. Изучено влияние расхода пероксида водорода и степени делигнификации исходной целлюлозы на белизну и показатели качества белёной целлюлозы. Проанализированы химические и механические потери волокна в процессе пероксидной отбелки недеревесного сырья.

    Исследовано использование отбеленной рапсовой целлюлозы в композиции с белёной сульфитной хвойной целлюлозой для получения офсетной и писчей бумаги. Показано, что увеличение доли рапсовой целлюлозы в бумаге повышает однородность, плотность, непрозрачность, что обеспечивает хорошие печатные свойства такой бумаге. Установлено оптимальные соотношения в композиции бумаг отбеленной рапсовой и сульфитной хвойной целлюлозы без снижения показателей качества. 


    The purpose of the present study was to define the impact of hydrogen peroxide at bleaching ability of fibrous semi-products obtained from the rape straw by neutral-sulfite process and their practical application. Rape pulp bleaching was carried out in environmentally friendly way using hydrogen peroxide without any chlorine compounds. Before bleaching, the pulp was treated with chelates. The effect of hydrogen peroxide consumption rate and delignification degree of initial cellulose at brightness and quality indicators of bleached cellulose were studied. The effect of anthraquinone catalyst on bleachability of semi-products was shown. Chemical and mechanical fiber losses in the peroxide bleaching process of non-wood raw materials were analyzed. The reduction the residual lignin content in the bleached pulp was confirmed, that explained the process of partial delignification. The impact of large number of small fibers on the quality of bleaching process and pulp brightness was determined.
    The ability of bleached and non-bleached pulp to fibrillate in the grinding process and their papermaking abilities was shown.
    The application of 100 % bleached rape pulp and its combination with bleached sulfite softwood pulp for producing of offset and writing paper was investigated. Original ash content positively effected paper sizing indicator. It was shown that increased share of rape cellulose in the paper improved the uniformity, density, opacity, that provides good printing properties of such paper. The influence of rapeseed pulp on strength of offset and writing paper was investigated.  The optimal ratio of bleached rape and sulfite softwood pulp in the composite without the reduction of quality was obtained. Writing paper №2 or offset paper № 2 of B grade could be produced from 100 % rape cellulose, while at least 50 % bleached softwood pulp is required for manufacturing of A grade paper, which complies with the standard.
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  • СОСНОВА ТИРСА: ДОСЛІДЖЕННЯ ФІЗИКО-ХІМІЧНИХ ХАРАКТЕРИСТИК СОРБЕНТУ

    Робота присвячена визначенню фізико-хімічних властивостей поверхні сорбенту (питомої площі поверхні, питомої густини кислотних та основних активних центрів), оскільки ці параметри є визначальними для ефективного вилучення важких металів зі стічних вод. Об’єктами досліджень були немодифікована та оброблена розчином карбаміду соснова тирса. Установлено, що після оброблення карбамідом питома площа поверхні тирси збільшилася на 35 %. Визначено, що кількість поверхневих карбоксильних груп зменшилася, лактонних – не змінилася, а відносна кількість фенольних груп значно зросла та з’явилися оснóвні групи, що є додатковими активними центрами сорбції.


    The main goal of the paper was to determine physicochemical properties of sorbents surface (specific surface area, the specific density of the acid and alkaline active centers) as they pay significant role in the effectiveness of water treatment process. The non-modified and modified by carbamide solution pine sawdust were the objects of the study.

    Determining of the surface of functional groups, with the presence of background electrolyte 0.1M NaNO3 to remain the constant value of the ionic power of solution, by acidic-alkali titration among temperature 20˚C the suspension of modified and non-modified pine sawdust were conducted.

    The value of specific surface area for modified and non-modified pine sawdust was determined from adsorption isotherm of methylene blue and constituted respectively 109 m2 and 147 m2. Adsorption of the dye goes on wet sorbent and the obtained numbers of specific surface area show conditions of sorbent, that was used for water purification, in a more realistic way.

    The water suspensions of modified and non-modified pine sawdust were titrated and the results were processed in the ProtoFit software. Best results while modelling 3-acidic active centres in case of non-modified sawdust and
    3-acidic and 1-alkali active centers, which are able to participate in proton exchange reactions in case of modified sawdust, were achieved.

    The improvement of sorption properties of pine sawdust after treatment by carbamide solution may be explained by changes of physical-chemical properties of its surface, namely, due to the formation of additional nitrogen-containing active sites, revealing alkaline properties at titration by acid.

    To sum up this paper, as a result of treatment by carbamide, the specific surface area increased at 35 %. Also, it was investigated by the acid-base titration followed by mathematical processing that quantity of surface carboxylic groups decreased, the quantity of lactonic groups was constant, while relative concentration of phenol acid groups increased and basic groups, which are the active centers of sorption of heavy metals, appeared.


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  • СУШІННЯ ПЕТ-ГРАНУЛЯТУ

    Досліджено вплив діаметра гранул, температури та тривалості сушіння на динаміку зміни вологовмісту ПЕТ-грануляту. Запропоновано регресійну модель сушіння у вигляді степеневої функції.


    Polyethyleneterephtalate (PET) is one of the most mass polymeric materials which are used for domestic and technical aims. Sixty year history of development of production of polymeric materials on the basis of PET includes development of both methods of processing of fusions polymer directly after a synthesis and through the stage of receipt of granulate. Presently anymore 80 % wares on the basis of this polymer make granulation with the use of the stage.

    Apparatus registration of drying of granulate is on enterprises which produce different wares on the basis of PAT, very various, but it is mainly realized in the vehicles of continuous action. Thus there is structural alteration of polymer which accompanies the deep (to 0,005 %) moving away of moisture from it that predetermines stability of further technological process. In this connection systematic studies of aspects of continuous drying of granulate of different size and development on this basis of corresponding recommendations are actual tasks.

    In this article results of experimental researches of drying PET-granulate are considered. The influence of pellet diameter, temperature and time of drying are researched. Mathematical model is indicated adequate to the process of drying.


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  • КІНЕТИКА БІОГАЗОВОЇ УТИЛІЗАЦІЇ ПАПЕРОВОГО ПАКОВАН-НЯ

    Розроблено математичну модель біогазового перероблення відходів паперового паковання, одержано її аналітичний розв’язок. Наведено теоретичні та експериментальні залежності кількості виділеного біогазу від тривалості перероблення за різних температур субстрату, за сталих концентраціях сухих речовин й ферменту та результати перевірки їх адекватності.


    One of the main objectives of developed countries is rational and economical use of energy. Despite the low development level of renewable energy today and disadvantages of energy strategy, Ukraine has good preconditions for further development of renewable energy and in particular bioenergy. Hundreds of tons of waste paper packaging are annually produced in Ukraine. Time of decomposition of paper packaging is from 1 to 400 years in the case of exclusion of film and foil lamination. Biogas released as a result methane fermentation of any organic matter. Therefore, studies to solve this problem by recycling paper packaging by means of fermentation and fermentation anaerobic fermentation in biofuels is important.

    Biogas – is a product of metabolism as a result of Vital Functions many groups of organisms of bacterias, that is a mixture of gaseous substances obtained by anaerobic, namely without air, and methane fermentation of organic matter. This mixture consists of approximately 65 % methane, 30 % carbon dioxide, hydrogen sulfide and 1 % minor impurities of nitrogen, oxygen, hydrogen and carbon monoxide. Regularities of methane fermentation process is extremely complex and depends on many factors, the most important of which are temperature, pH and concentration of dry matter.

    Highlight the four most important stages, namely: hydrolysis, acidogenesis or biological oxidation or acetogenesis or acid fermentation and the last stage, methanogenesis, at this stage 90 % methane is synthesized, 70 % of which comes from acetic acid.

    Among the technological parameters on the speed decoupling most valuable impact is the temperature of the substrate, for her, there are three modes, each of which has the speed of substrate cleavage and the speed of biogas. Temperature is the main parameter in terms of research and process optimization for the temperature regimes.

    The aim of this article is analytical research of the kinetics of the concentration field of the liquid and gas phases in bioreactors operating without stirring.

    Developed a mathematical model of the biogas process of recycling waste of paper packaging, the analytical solution of a mathematical model for a given initial and boundary conditions, which provides new biogas dependence of selected depending on the time and temperature at a given solids concentration and amount of enzyme.

    In order to conduct a pilot study to confirm the adequacy of dependency, the analytical solution of the mathematical model developed laboratory setup consisting of insulated bioreactors periodic operation and the gas container, which are interconnected.

    From Dependence found that most slow release biogas process takes place at a temperature of 20 оС, the maximum rate is observed at 50 оС. However, the specific biogas yield at different temperatures remains the same, changing only the rate of release of biogas.

    Analysis of the theoretical and experimental dependences shows that temperature influences the rate of biogas yields during biochemical processing of laminated paper packaging. A mathematical model with sufficient accuracy describes the kinetics of the process at different temperatures of the substrate.

    Adequate theoretical dependences experimental data was checked and confirmed by the Fisher criterion.


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  • ВПЛИВ ВИБІЛЮВАЛЬНИХ РЕАГЕНТІВ НА ЯКІСТЬ ЛЛЯНОЇ ЦЕЛЮЛОЗИ

    Досліджено вплив двооксиду хлору, пероксиду водню й хлору на вихід, вміст залишкового лігніну, a-целюлози, в’язкість, зольність і білість натронної лляної целюлози для хімічної переробки. Установлено, що одностадійне оброблення лляної целюлози з витратою двооксиду хлору 0,4...0,5 % і пероксиду водню 2...3 % від маси абсолютно сухої целюлози є ефективнішою, аніж оброблення хлорною водою з витратами хлору 3…4 % від маси абсолютно сухої целюлози  із подальшим лужним обробленням, оскільки сприяє кращому видаленню лігніну зі збереженням вмісту a-целюлози і незначному зменшенню в’язкості, а також підвищенню білості целюлози вдвічі.


    The paper studies the impact of bleaching chemicals such as chlorine dioxide, hydrogen peroxide and chlorine on the product yield, residual lignin content, a-cellulose, viscosity, ash content and whiteness of flax natron cellulose for chemical processing.

    It was found that one-step processing of flax pulp with chlorine dioxide consumption rate 0,3…0,5 % and with hydrogen peroxide consumption rate 2…3 % by weight of abs. dry cellulose is more effective than treatment with chlorine water at chlorine consumption rate 3 ... 4 % by weight of abs. dry cellulose followed by alkaline extraction because it provides better removal of lignin, the retaining of a-cellulose and slight decrease of viscosity as well as and increase pulp brightness as much as twice compared to unbleached pulp.


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  • ЛУЖНО-СУЛЬФІТНО-СПИРТОВА ДЕЛІГНІФІКАЦІЯ СТЕБЕЛ СОНЯШНИКУ І СВЕРБІГИ

    Доведено, що стебла соняшнику і свербіги східної можна переробити лужно-сульфітно-спиртовою делігніфікацією у волокнисті напівфабрикати (ВНФ), які за фізико-механічними показниками наближаються до технічної целюлози з листяних порід деревини. Одержано залежності показників якості ВНФ від температури й тривалості делігніфікації.


    Stems of Helianthus annuus and Bunias can be processed into semi-finished fiber products using alkaline sulfite-alcohol delignification. These semi-finished fiber products in their physical and mechanical characteristics are similar to those of the pulp of hardwood. The dependences of quality semi-finished fiber products on the temperature and duration of delignification are obtained.


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  • ОСОБЛИВОСТІ ВИРОБНИЦТВА БІОДИЗЕЛЬНОГО ПАЛИВА

    Проаналізовано переваги та недоліки, джерела сировини, технологію виробництва та застосування біодизельного палива. Надано рекомендації щодо розвитку біопаливної галузі в Україні.


    Biodiesel has several advantages compared with conventional fuels, both environmental and operational. But these benefits should not be offset by the potential negative environmental impacts associated with land use or improper use of obsolete technologies.

    Biodiesel is not a panacea for energy diseases. Its implementation requires solving a number of problems: biodiesel are usually made from plant material, the scope of which is limited to the needs of the food industry; use of energy efficient technologies is not enough until you can reduce high compared to conventional fuel production cost of biofuel; due to the presence of oxygen biofuel has less energy consumption than its hydrocarbon analogs, which affects the efficiency of its use and performance; application does not guarantee biofuels reduce emissions of toxic gases; any biofuel enjoys limited support from consumers (because its operational and economic characteristics need to be improved), car manufacturers (which is primarily concerned about its corrosivity), and oil refiners (see it as a opponent).

    In addition, biofuels is the same finite resource, like oil, because during its production is consumed (often – irreversibly) the fertility of agricultural land. Therefore grown in our country, the raw material for the production of biofuels should be directed primarily to the needs of Ukrainian consumers, and the task of the state – contribute to this.

    For sustainable biofuels industry in Ukraine need a coherent and systematic plan of action aimed at least ten years. According to the authors, it would be advisable to do the following steps to complete the following areas: fiscal and regulatory support, regional development, infrastructure development, environmental sustainability, information and education.


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  • ХАРАКТЕРИСТИКА БАКТЕРІЙ, ВИДІЛЕНИХ ІЗ ВУГІЛЬНОГО ФІЛЬТРА СИСТЕМИ ПІДГОТОВКИ ВОДИ БРОВАРНОГО ВИРОБНИЦТВА

    Зі змивів з активованого вугілля виділено та охарактеризовано три найпоширеніші спорові бактеріальні культури, що можуть відігравати вирішальну роль в утворенні біоплівки у вугільному фільтрі під час доочищення води, яку використовують у виробництві пива.


    When using the sorption coal filters for treatment and advanced water treatment, a biofilm – aggregate of contamination particles, microbial cells and the products of their metabolism – is formed on the coal surface. The named particles are attached to each other and enclosed in a matrix of their extracellular polymeric synthesized compounds. Such community of microorganism has the changed phenotype which is occurred in other parameters of growth, a reproduction speed and an expression of specific genes. A uniform genetic system is established in a biofilm in the form of plasmids which define social behavior of microorganisms. The coordinated activity of microbes’ community makes biofilms to be low-vulnerable to disinfectants and factors of macro-organism protection, and the removal of the film from any surface becomes a challenging task. Therefore over time, there is a need in filters flushing for the biofilms removal in order to restore the filter effectiveness and to prevent secondary contamination of purifying water as it can be dangerous to human health. The study of morphologic-cultural and physiological-biochemical properties of bacteria forming a film is necessary for the development of rational methods of filters cleaning and the improvement of the quality of treated water.

    The paper studies biological features of biofilms at active carbon filters used in industrial process water treatment systems of an enterprise producing special drinks. The three most common bacterial cultures, which can play a key role in the biofilms formation in the carbon filter in advanced water treatment for beer production, have been isolated and characterized from swabs from the activated carbon. All three selected bacterial cultures are identified as members of the genus Bacillus. The obtained data are the basis for the development of more effective methods for a biofilm removal from the activated carbon surface at the industrial filters for the brewing industry, and/or combination temperature sanitation with other technologies.

    The present paper studies biological features of biofilms at active carbon filters of water treatment systems for process water at the enterprise of special drinks. Three most common bacterial cultures, which can play a critical role in the formation of biofilms in the carbon filter at water purification used for beer production, were isolated from swabs from the activated carbon and characterized. The obtained data are the basis for the development of more effective methods for the removal of biofilm from the surface of the activated carbon filters at the brewing industry, and/or combination of temperature sanitation with other techniques.


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  • ВИКОРИСТАННЯ МАГНЕТИТУ ДЛЯ ОЧИЩЕННЯ СТІЧНИХ ВОД ВІД НАФТОПРОДУКТІВ

    Проаналізовано використання сорбентів із магнітними властивостями для очищення водних середовищ від нафтопродуктів і відокремлення частинок магнетиту від очищеної води. Визначено чинники вкливу на дисперсність гранульованого магнетиту й вивчено його сорбційні властивості. Досліджено вплив швидкості фільтрування на ефективність сорбції нафтопродуктів гранульованим магнетитом. 


    The article deals with the problems of global hydrosphere pollution by oil and petroleum products. The application of different magnetic sorbents for the removal of petroleum products from water is analyzed. The problem of separation of magnetic particles of sorbents from treated water is discussed. The possibility of using magnetite particles for oil separation from water and simultaneous localization of solid phase in the sorption column in a dynamic mode is investigated. In cases of chemical condensation techniques, very low filtration properties of a media formed with magnetite particles are obtained. The possibility of increasing the dispersion of magnetite particles by extension and different methods of granulation magnetic sorbents has been studied. A number of factors affect the dispersion of granular magnetite. Particle size distribution of the suspension is influenced by the concentration of the initial solution. A significant impact of synthesis and thawing temperatures on the size distribution of magnetite slurry has been observed. The graphs, illustrating the effect of concentration of initial components and different thawing temperatures on a variety of granular magnetite particles used as a filter media for sorption filters, have been presented. The influence of freezing/thawing temperature on size distribution of granular magnetite has been investigated. A sorbent based on granular magnetite with satisfactory filtration properties has been obtained. The absorption properties of granular magnetite have been studied. It was defined that despite the lower dispersion of magnetite particles after freezing, its absorption properties were better than conventional magnetite. The maximum sorption capacity to oil products has been determined for traditional and granulated by freezing magnetite. It is shown that the curves of sorption for both types of magnetite are characterized by relatively clear and steep slope. It is concluded that the absorption properties of granular magnetite allow the application of the studied sorbent for treatment of industrial water, polluted by oil and petroleum products. The impact of filtration rate using filtration and sorption systems operating in dynamic mode has been analyzed. It has been determined an optimal flow rate of contaminated water and relations between the filtration rate and oil sorption effectiveness of granular magnetite. The influence of the height of the layer of granular magnetite on oil removal efficiency of sorption filters has been defined. Even though the freezing and thawing processes in an industrial conditions are costly, the increase of the filter layer thickness or multi-use cleaning system allow to effectively run water treatment at filtration rate appropriate for industrial equipment.

    The use of magnetic sorbents for the purification of water environments from oil was analyzed. The problem of separation of magnetite particles from purified water was considered. A number of factors affect the dispersion of granular magnetite. The absorption properties of granular magnetite were studied. The effect of velocity filtering efficiency of oil sorption granular magnetite was defined. 


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  • ВИЛУГОВУВАННЯ ВАЖКИХ МЕТАЛІВ ІЗ МАТЕРІАЛІВ ХВОСТОСХОВИЩ УРАНОПЕРЕРОБНОЇ ПРОМИСЛОВОСТІ

    Наведено дослідження кінетики вилуговування Mn, Ni, Cu, Pb, Fe із матеріалів хвостосховищ «Дніпровське» і «Центральний яр». Експерименти з вилуговування важких металів проводили за методикою визначення швидкості вилуговування радіонуклідів із радіоактивних відходів (ГОСТ 29114-91). За отриманими даними обчислили константи швидкості вилуговування важких металів із твердої матриці та константи їх виходу у розчин.


    Mining and processing of uranium ores associated with many environmental problems. Along with the pollution of natural radionuclides environment, waste tailings uranium processing industry is also a source of contamination of ground and surface waters with heavy metals. Tailing waste on processing of uranium former «Prydniprovsky chemical plant» studied only in terms of distribution and migration ability of radionuclides. Any data on migration ability of heavy metals, but their content in the solid phase of waste and natural waters is not available.

    Purpose of work is study the kinetics of leaching of metals from tailings materials industry in uranium processing.

    In this paper deals with the kinetics of leaching of Mn, Ni, Cu, Pb, Fe material from tailing «Dneprovske» and «Central yar» Experiment with the leaching of heavy metals was carried out by the method of determining the rate of leaching of radionuclides from radioactive waste (GOST 29114-91). From the data obtained were calculated rate constant leaching of heavy metals from a solid matrix and constant release of their solution.

    The results showed that the rate of leaching of heavy metals from tailings samples «Central yar» is almost an order of magnitude higher than samples from tailings «Dniprovske». This can be caused by several factors, including the first differences of the material composition of waste materials, physical and chemical conditions that occur in the tailing. In particular, the tailings are significantly different for the acid-alkaline conditions: the tailing «Central yar» pH are acidic or weakly acidic region, while in tailing «Dniprovske» – in near neutral or even slightly alkaline in. For the lower horizons of the studied both tailing characteristic are lowest rate of leaching of heavy metals. This is especially noticeable for the sample tailing «Dniprovske» 18,7…19,2 m of depth. This can be explained by the fact that the lowest horizon from which sampling was carried out, is underlain by breeds and contain no technogenic waste. The exception іs the lead (plumbum), which is the lowest rate of leaching tailings sample «Dniprovske» 14,8…15,2 m of depth. In tailing «Central yar» migration ability of metals is decreases in the number Mn > Fe > Pb > Ni > Cu. Such a trend is observed for all samples of the tailings. As for tailing «Dniprovske”, a series of migration ability of heavy metals can be set as follows: Mn > Fe ≈ Pb > Cu. Speed Ni leaching into the solution of tailings material «Dniprovske» significantly decreases with depth compared with other metals, so each patient horizon of the tailing position of nickel in some migration ability of metals will be different. The difference between these two tailings on the migration behavior of nickel can be explained by several factors, which are mainly caused by chemical and mineral composition of waste. Also play an important role physical (porosity, humidity) and water (permeability, swelling, filtration coefficient) properties of rocks contained in the tailing. However, these issues have not been fully addressed and require detailed study.


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  • ОЦІНКА ВПЛИВУ ІОНІВ ТВЕРДОСТІ НА ЕФЕКТИВНІСТЬ ОЧИЩЕННЯ ВОДИ ВІД ІОНІВ МІДІ

    Вивчено сорбцію іонів міді та йонів твердості на сильнокислотному КУ-2-8 і слабокислотному Lewatit TP-207 катіонітах за динамічних і статичних умов. Показано, що слабокислотний катіоніт має обмінну ємність за іонами міді на рівні сильнокислотного катіоніту. Установлено, що за динамічних умов під час сорбування йонів міді у присутності йонів жорсткості обмінна ємність іонітів за йонами міді зменшується. При цьому більше зниження помічене для сильнокислотного катіоніту та йонів кальцію. За невисоких концентрацій іонів міді іони кальцію менше знижують ємність сильнокислотного катіоніту за іонами міді порівняно із слабокислотним, а за концентрацій понад 100 мг/дм3 більш селективним є слабокислотний катіоніт. Установлено, що сильнокислотний катіоніт ефективно регенерується розчинами хлориду й сульфату натрію, а слабокислотний – соляної кислоти.

    The sorbtion processes of copper ions and hardness ions are studied on strong-acid kationite KY-2-8 and low-acid kationite Lewatit TP-207 in dynamic and statistic conditions. It was shown, that low-acid kationit has an exchange capacity toe copper ions of at the level similar to strong-acid kationite. It is determined that in dynamic conditions the sorption of copper ions is declined in presence of hardness ions. Greater decline is observed in case of strong-acid kationite compared to low-acid one; calcium ions reduce exchange capacity to larger extent compared to magnesium ions. As derived from the sorption isotherms, at the low concentrations of copper ions, calcium ions reduce the capacity of strong-acid kationite to copper ions to less extent compared to low-acid one, but at concentration of copper >100 mg/dm3 low-acid kationite is more selective.

    The regeneration processes of kationites are studied and it is shown that strong-acid kationite is effectively regenerated by solutions of sodium chloride and sodium sulfate, while low-acid kationit – by muriatic acid solutions.

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  • ГІДРАВЛІЧНА СЕПАРАЦІЯ ПОЛІМЕРНИХ ПАКУВАЛЬНИХ МАТЕРІАЛІВ

    Розглянуто проблему гідросепарації вторинних полімерів. Розроблено математичну модель процесу, проаналізовано умови занурення полімерів у воду та їх відокремлення від інших твердих побутових відходів.


    Hydraulic separation is a way of separating solid waste (MSW) into components with water. The technology is cheaper than incineration, with relatively rapid deployment. With the technology of hydro solid waste can be recycled up to 85 % of unsorted waste, which then will be used to rework both recyclables and organic waste – production of biogas and electricity.

    For hydraulic sorting of solid waste using water, which is a natural odor neutralizer. Originally unsorted waste coming into the emergency department, equipped with exhaust fans. They were then passed through a stream of water where organic and inorganic components are separated by gravity regulate water flow.

    The purpose of this paper is the problem of sorting waste by hydro polymer material in which plastics are sorted from the total weight of waste by adding air to the water, which changes its density, resulting in getting water-air mixture in which the polymers are not emerges the surface, and begin to settle, as their bulk density greater than the density of the resulting mixture.

    Ten years ago, the term hydraulic separation was very new to the vocabulary used in the North American hydronics market. Back then the contemporary topic being discussed and applied was primary/secondary piping. The idea being that several loads, each served by its own secondary circuit and associated circulator, could be connected to a common primary loop, with its own circulator. The «magic» of closely-spaced tees is what prevented the flow rate in any of these circuits from interfering with the flow rate in the others.

    In essence, that is what hydraulic separation is: the ability of two or more circulators within the same piping system to simultaneously operate without interfering with each other.


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  • ФІЛЬТРУВАЛЬНИЙ МАТЕРІАЛ ДЛЯ БАРОМЕМБРАННОГО ОЧИЩЕННЯ ВОДИ

    Стаття присвячена отриманню з сульфатної хвойної вибіленої целюлози фільтрувального матеріалу для очищення води від завислих і колоїдних частинок, що обумовлюють її каламутність. Досліджено вплив вмісту лавсанового волокна та клею на основі полівінілового спирту на механічні та експлуатаційні характеристики фільтрувального матеріалу. 


    This article is devoted to the obtaining of filter material from bleached softwood sulphate pulp for water treatment under increased pressure from suspended solids and colloidal particles, which determine water turbidity, and the evaluation of the filter material properties. The influence of the filter material composition (the content of lavsan fibers and adhesives based on polyvinyl alcohol) as well as surface sizing and the mechanical performance of the filter material. The mechanical strength of the samples was determined by the bursting strength factor. The maximum values of the factor for the samples without surface coatings were obtained at the consumption rate of adhesive 50 % and lavsan 15 % by weight of absolutely dry fiber. Adhesive surface coating can improve bursting strength of the filter material by 66…77 %, and the filter material composition has almost no effect at the growth rate.

    The evaluation of the effectiveness (performance characteristics) of the samples was carried out by their selectivity for turbidity and productivity. The investigations were conducted by filtering distilled water, barium sulfate suspension with concentration 4250 mg/dm3, obtained by deposition, and kaolin slurry with concentration of 5000 mg/dm3. The filtration was carried out at increased pressure: from 0.25 to 1.75 atm for samples with no surface coating, from 3 to 4 atm for samples with surface coating. The decrease of performance during filtration with constant pressure was observed for all samples. Samples with the maximal initial performance showed the largest (almost twofold) loss of productivity in the first minutes of filtration. The increasing of the pressure improved the performance while keeping selectivity.

    As a result of studies, samples of filter material were obtained, that provided selectivity to suspended and colloidal particles, causing water turbidity, at a level of microfiltration membranes. These materials can be used for rough water treatment or water preconditioning before advanced purification.


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  • ВПЛИВ КОНСТРУКТИВНИХ І ТЕХНОЛОГІЧНИХ ПАРАМЕТРІВ ПРОЦЕСУ ФОРМУВАННЯ ТЕРМОПЛАСТІВ НА ЯКІСТЬ ЕКСТРУДОВАНОЇ ПРОДУКЦІЇ

    Розглянуто процеси екструзійного формування безперервних виробів із термопластичних матеріалів та устатковання для їх реалізації. Проаналізовано проблеми, що виникають під час екструзійного формування, і засобів їх усунення, запропоновано шляхи  удосконалення існуючих формувальних пристроїв. 


    Meeting the needs of geometric complicated articles of plastic is impossible without optimizing design and process parameters of equipment and processes of polymers and compositions with their use. Ultimate parameters of the polymeric and composite production are takes into forming tool.

    In the design of the forming equipment we must consider that its working channels can has different geometry and processed material – different hydrodynamic and thermal regimes. All of these parameters bound to change the rheological properties of the processed material.

    The aim of the paper is to analyze the main factors that affect the quality of the process of polymer products extrusion forming, and means to eliminate defects in extruded products.

    For high speed extrusion the conditions for achieving marginal adhesion strength can be created and defective surface arise as a result of highly turbulence. This phenomenon is predicted to achieve a theoretical or experimentally determined critical shear rate. Typically, this problem can be eliminated by reducing the rate of extrusion, increasing the temperature in the forming extrusion die channels, and by addition of external lubricants into the polymer.

    For compensation of these effects a new extrusion die design was proposed, which structural elements can absorb vibrations occurring. Annular extrusion die contains a matrix that forms the outer surface of the polymer product, and mandrel, forms the inner surface of the product and which the input and output parts consists. The output parts of the matrix and mandrel are fixed in the moving part of mandrel support, and creates a channel for the melt flow with the output area, and besides the matrix and the output of the mandrel can move back and forth along the axis relative to the fixed part mandrel support with changing of the channel length for the melt flow. In matrix elastic and damping elements are placed that transmit force from it on the cover. The melt was included in the die, enters in the channel between the output mandrel part and the input part, and forms a pressure drop, which leads to the formation of an axial force that moves the matrix of the original part mandrel and moving parts of the mandrel support relatively fixed part of the mandrel support. The length of the channel increases, and the pressure in the die starts to decrease. Matrix, moving in the axial direction, passes through the efforts of the lid damper that reduces the speed of movement, and the spring that tries to take the matrix to its original position. As the process is continuous, as the matrix of the input part of the mandrel takes reciprocates, thereby absorbing pulsation.


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  • ПІДВИЩЕННЯ КОРОЗІЙНОЇ СТІЙКОСТІ ПЛАЗМОВИХ ПОКРИТТІВ НА ОСНОВІ ПЛАКОВАНОГО ПОРОШКУ ОКСИДУ АЛЮМІНІЮ

    Експериментально досліджено корозійну стійкість покриттів, отриманих плазмовим напилюванням порошку оксиду алюмінію плакованого двошаровими оболонками з титану, алюмінію або міді на сталеву та магнієву основу. Проведена термодинамічна оцінка взаємодії оксиду алюмінію з металевими оболонками при плакуванні. Встановлено вплив плакованих порошків на мікроструктуру та пористість плазмових покриттів і зміну поляризаційного опору під час випробувань в рідких агресивних середовищах.


    Corrosion resistance coatings deposited by plasma spraying of alumina powders with clad metal PVD film were studied. Thermodynamical evaluation of the interaction of alumina with titanium and copper in cladding was produced. Possibility of interaction was evaluated assuming that the alumina dissolved in the titanium. The result was defined atomic percentage of oxygen and aluminum in the titanium at temperature of cladding. The influence of clad powders on the microstructure, porosity and polarization resistance of plasma-sprayed coatings during testing in corrosive environments was studied. The corrosion behavior of coating was studied by technique of a polarization change based on the measurement of the current between the two electrodes from the same metal and a coating when applied the polarization less than 20 mV.

    Alumina powder for plasma spraying coated dual layer of titanium, aluminum or copper reduces the total porosity and improves in a 2–3 times the corrosion resistance of coated steel in 10 % solution H2SO4, HNO3 as well as more than an order of corrosion resistance of magnesium alloy in a 3 % NaCl solution.

    Largest values at spraying on steel substrate of the polarization resistance in acid solutions respond coatings from alumina powder with dual layer clad PVD film of titanium and copper. This increase in the corrosion resistance depends more on the thickness of the top sprayed coating than to the material and thickness of sprayed underlayer. It is associated with a decrease in the amount connected pores. Largest values at spraying on the magnesium alloy of the polarization resistance in 3 % NaCl solution had coating on base of clad alumina powder with underlayer and the additional activation of the substrate surface by electrospark doping for improving adhesion strength.

    Further research perspectives are to enhance materials for clad powders and more detailed studying of the corrosion damage mechanism at elevated temperatures of plasma-sprayed coatings from clad powders.


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  • ДВОСТАДІЙНЕ ТЕРМОУСІДАННЯ ПОЛІПРОПІЛЕНОВОЇ ТЕРМОУСАДНОЇ ПЛІВКИ

    Наведено результати експериментальних досліджень двостадійного термоусідання поліпропіленової термоусадної плівки. Визначено залежності коефіцієнта усідання поліпропіленової плівки в поперечному та поздовжньому напрямках від температури. Порівняно одно- і двостадійне термоусідання.


    Shrinkage called polymer films capable to contract under the influence of a temperature exceeding the softening temperature of the polymer. Different polymers have different properties at shrink, among which the most important is the shrink degree (shrink coefficient) and shrink stress. Shrink coefficient determines the multiplicity of reducing the linear dimensions shrink film, so that it gets the ability to tightly encircle the products subject to packaging, reproducing its outer contours.

    The process of packaging products in shrink film consists of two phases: formation package by sealing it in shrink film; shrinkage of the film through its blowing hot air. Hot air is blowing of package realizing by heat chamber or by heat tunnel.

    The aim of the paper is to investigate the shrink coefficient polypropylene film in the transverse and longitudinal directions, depending on the process temperature.

    During the implementation of the shrink method in case the object is subjected packing, sharp transitions or sharp edges possible undesirable deformation and/or damage to the object itself, or injury (up to fracture) packaging film (that is destroying the integrity of the package), it would be appropriate to use a two-step incremental shrinkage. Stepwise shrinkage was carried out in two stages: the first stage of the film was in the heat chamber 2 s, and at the next shrink stage – 5 s. In carrying out the experiment was seen addiction at the time that the first shrink stage exceeding 2 s, the relaxation of the film makes it almost fully realized and further shrinkage is negligible. After finishing shrinkage processes coefficient determined after the first stage and the overall shrink and total in the transverse and longitudinal directions, depending investigated transverse and longitudinal coefficients shrink temperature.

    A comparison of the experimentally obtained graph of the one-step and two-step in shrink follows that when shrink film at one stage, shrink ratio is increasing with increasing operating temperature, whereas the two-stage shrink biggest factor shrink was obtained at a temperature 170oC . The total shrink degree in two-stage process is almost the same as in the one-step shrink.


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