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A new type of polydimethylsiloxane-based paper transparentizing agent was prepared via a combined method. The performance of the transparentizing agent was investigated systematically by adding and dipping, with use of the surface sizing device of a paper machine. Optimum performance was found at 30% concentration of the transparentizing agent and 30 to 45 °C of dipping temperature. Under the optimal conditions, the transparentizing t agent achieved a rapid penetration in the base paper and filled in the pores of the paper, to be further effectively adsorbed and retained on the fiber surface. The transparency of test paper reached as high as 76±0.97 %, which was 37±1.4% higher than that of the control. However, the addition of transparentizing agent reduced the mechanical strength of paper slightly. The as-prepared transparentizing agent was found to exhibit excellent application stability and biodegradability when applied in the paper machine，When used as plastic film, the transparent paper would lose its strength completely after eight weeks. The resulting transparent paper can be used to develop paper-based film and other related plant based transparent/ translucent paper, which has great potential in replacing plastic products and eliminating white pollution.

Tissue paper conversion consists of the transformation of base tissue papers into finished tissue products to meet specific demands. When base tissue paper arrives at the converting line, it already holds different requirements that were met during its manufacture in the paper machine (e.g., grammage, bulk, tensile index, etc.). However, what happens during converting can still influence the performance and quality of the finished products. The current work addresses this topic and aims to evaluate the influence of converting conditions on the final softness. For that, two 5-ply finished tissue products were analyzed using different methodologies for their proper characterization in terms of softness and surface analysis. The analyzed products are composed by the same base tissue papers, but some changes were applied on their settings in the converting line. In particular, the base tissue papers arrangement and the embossing pressure affected the finished products, resulting in one of them being softer and more pleasant to touch, with a global handfeel (HF) value of 75.3 units, and the other revealed to be rougher and less pleasant, with a global handfeel (HF) value of 68.0 units.

The paper presents the method for assessment the performance of high-speed Yankee hoods in the production of tissue paper grades and the results of its use in working machine. The following parameters are found applying this method: paper web dryness, air pressure in the wet and dry ends of high-speed convective dryers and temperature of the air spilled out of the hoods. The methodology is based on the measurement of these characteristics during the operation of working equipment with further adjustment of the separate system units. Thermal imaging was carried out during the experiment. It has been found that blowing hot air on the front side of the hood and sucking in the cold air on the drive side leads to uneven moisture profile (measured on the paper machine roll) across the paper web width, a decrease in energy efficiency and the machine capacity. Performance indicator may be, for instance, the spilled air temperature, which on the studied machine is significantly different from the standard value and is 175 °C. The rationality of regular monitoring of air characteristics when changing processing modes is proved. The relevance of the cascade system is substantiated, where not only a direct cascade from the dry end to the wet end is possible, but also there is an opportunity to adjust the humidity of exhaust air by addition/reduction of part of it to/from the dry end. The direct effect of adjusting the humidity of exhaust air in the drying section on reduction of energy costs, as well as the effect of make-up air on the amount of infiltration and the air balance of the system are confirmed. A set of measures implemented within the framework of this methodology makes it possible to achieve energy saving in existing industries. The prospective saving potential of gas is 62 m3/h or 17 % of the current consumption and actual electricity consumption is 6.8 kWh or 4 % for the studied machine. For citation: Prokhorov D.A., Smolin A.S. Performance Assessment of the Drying Section of Machines for the Production of Tissue Paper Grades. Lesnoy Zhurnal[Russian Forestry Journal], 2020, no. 2, pp. 159–168. DOI: 10.37482/0536-1036-2020-2-159-168

In article results of balancing of unki-cylinder papermaking machines are submitted. The Unki-cylinder balancing on a place of his installation on papermaking machines on trial and error method of adjusting weights. Parameters of vibration have decreased after balancing on an obverse support – in 2.1 times, приводной to a support – in 2.7 times. Stability of loading of a drive after balancing has considerably improved. Представлены результаты балансировки янки-цилиндра бумагоделательной машины. Янки-цилиндр отбалансирован на месте его установки на бумагоделательной машине по методу подбора корректирующих масс. Параметры вибрации уменьшились после балансировки на лицевой опоре в 2,1 раза, приводной опоре в 2,7 раз. Стабильность нагрузки привода после балансировки значительно улучшилась.

Система керування напірним ящиком відкритого типу має високу складність, що пов'язано із необхідністю не тільки стабілізувати параметри об’єкта, але й здійснювати координоване керування ним у випадку автоматичного переведення папероробної машини з одного виду продукції на інший за мінімальний час. Розроблено математичну модель напірного ящика відкритого типу як об’єкта керування рівнем маси. У моделі вихідною змінна об’єкта керування є рівень маси у напускній камері, а керувальним діянням є витрата маси, що подається до напускної камери. В моделі враховано збурювальне діяння – площу випускальної щілини. На основі розробленої моделі розглядається два варіанти побудови алгоритму керування напірним ящиком під час переведення його із одного режиму у інший. Розроблено структуру алгоритму координованого керування напірним ящиком. Наведено ілюстративний приклад застосування розробленого алгоритму. Здійснено розрахунки оптимального перехідного процесу в об’єкті які підтверджують ефективність розробленого алгоритму керування. Алгоритм координованого керування застосовано для стандартного напірного ящика ЯНО-180. Продемонстровано розробку алгоритму переведення напірного ящика з робочої (0,485 м) на максимальну (0,575 м) висоту рівня маси у напірному ящику за час 180 с. Результати розрахунків показують, що алгоритм координованого керування забезпечує переведення рівня маси на максимальну висоту за заданий час. Розроблений на основі отриманої математичної моделі алгоритм дозволяє здійснювати керування рівнем маси у такому складному об’єкті, як напірний ящик відкритого типу при переведенні папероробної машини з одного режиму роботи на інший за час, вказаний системою координованого керування. The control system of an open-type headbox has a high complexity, which is associated with the need not only to stabilize the parameters of the object, but also to carry out coordinated control of it in the case of automatic transfer of a paper machine from one type of product to another for a minimum time. A mathematical model of an open-type headbox as an object of mass level control has been developed. In the model, the output variable of the control object is the level of mass in the injection chamber, and the control action is the mass flow rate supplied to the injection chamber. The model takes into account the disturbing action - the area of the discharge slot. On the basis of the developed model, two options for constructing an algorithm for controlling the pressure box during its transfer from one mode to another are considered. The structure of the algorithm for coordinated control of the pressure box is developed. An illustrative example of application of the developed algorithm is given. The calculations of the optimal transient process in the object confirm the effectiveness of the developed control algorithm. The algorithm of coordinated control is applied to the standard pressure box YANO180. The development of the algorithm for transferring the pressure box from the working (0.485 m) to the maximum (0.575 m) height of the mass level in the pressure box for 180 seconds is demonstrated. The calculation results show that the coordinated control algorithm provides the transfer of the mass level to the maximum height for a given time. The algorithm developed on the basis of the obtained mathematical model allows to control the level of mass in such a complex object as an open-type headbox when transferring a paper machine from one mode of operation to another for the time specified by the coordinated control system.

Technological factors of influence on the paper web processing quality in paper machines are analysed. Тhe process of paper web pressing theoretical aspects are considered from the standpoint of the mechanics of dispersed moisture-saturated materials. The microfragment model of a moisture-saturated porous paper material is proposed. A method for determining the technological parameters of paper pulp mechanical dehydration in the manufacture of printing paper has been developed. A methodological approach to the creation of a mathematical model of the process of pressing paper semi-finished products in a paper machine from the standpoint of the mechanics of dispersed moisture-saturated materials. Analytical equations describing the regularities of the kinetics of liquid phase separation and compaction of the solid framework of the dispersed system are obtained. The proposed methodological aspects can be used to determine the rational modes of operation of press equipment in the technology of paper production for various printing purposes. The mathematical model of the paper web pressing process allows taking into account the shape and particle size of the material and the kinetics of water separation. Regularities of the liquid phase separation and the solid frame consolidation of the dispersed system at the stage of paper web pressing have been established. The proposed models allow the development of ecological regimes for the paper semi-finished products dehydration by reducing the use of water and greenhouse gas emissions., Проаналізовано технологічні чинники впливу на якість обробки паперового полотна у папероробних машинах. Розглянуто теоретичні аспекти процесу пресування паперового полотна з позицій механіки дисперсних вологонасичених матеріалів. Запропоновано модель мікрофрагменту вологонасиченого пористого паперового матеріалу. Розроблено методику визначення технологічних параметрів механічного зневоднення паперової маси при виготовленні друкарського паперу. Математична модель процесу пресування паперового полотна дозволяє враховувати форму і розміри часток матеріалу та кінетику відокремлення води. Встановлено закономірності відокремлення рідкої фази та ущільнення твердого каркасу дисперсної системи на етапі пресування паперового полотна. Запропоновані моделі дозволяють визначити екологічні режими зневоднення паперових півфабрикатів шляхом зменшення використання води та викиди парникових газів.