On the modeling of paper pulp dewatering and forming processes in the wet end of the paper machine

The quality of paper depends on the efficiency of the dewatering forming processes of paper machines (PMs). Initial forming and dewatering processes, such as filtering water through the fabric to form a settling fiber layer, are performed on the PM fabric table. The efficiency of the forming process is predetermined by the character of changes in the mass concentration and height of the suspension layer along the forming table. At the moment, the issue of program simulation of processes and productions is relevant, because it allows you to get away from the physical experiment. Proceeding from the topicality of the question, the main purpose of the research was to develop an algorithm for modeling the process of dewatering on the PM forming table and its software implementation to justify effective design parameters of dewatering elements. To realize the goal set and solved a number of tasks: specification and substantiation of theoretical principles of calculation of the processes of dewatering; substantiation of the algorithm of calculation and its software realization; simulation of the process as applied to the real process of dewatering for offset paper and the development of recommendations for optimization of constructive parameters of dewatering elements on the basis of the data of simulation; using the developed algorithm and the specially developed program making it possible to carry out calculation of dewatering elements for offset paper. On the basis of the researches made and the results of modeling the scientifically substantiated recommendations for improving the layout of dewatering elements and the angle of hydrofoils slope are developed. Changing the working angle of inclination of hydrofoils at the investigated section increases efficiency of dewatering in the register part by 4.6%, which will allow increasing dryness of paper web at the outlet of the zone and achieving greater energy efficiency without significant investments into modernization.

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