INFLUENCE OF THE PATTERN OF THE COMBINED GRINDING SET OF THE DISC MILL ON INDIVIDUAL PAPER-FORMING PROPERTIES OF FIBROUS SEMI-FINISHED PRODUCTS AND THE PHYSICAL AND MECHANICAL CHARACTERISTICS OF THE FINISHED PRODUCT

Abstract

The improvement of the process of grinding fibrous semi-finished products in pulp and paper production is caused by a reduction in the raw material base, requirements for the quality of finished products, as well as the desire to reduce production energy costs. Changing the grinding parameters allows you to change the properties and characteristics of the resulting materials in a wide range. The main controlled parameters of the grinding process are the gap between the rotor and stator disks, the rotor speed, the concentration of the fibrous mass. One of the important parameters of the grinding process is also the design of the grinding set. The article considers the influence of various configurations of cavities of the combined grinding set of a disc mill on the properties of the fibrous mass and finished paper castings. Individual paper-forming properties were evaluated, including the increase in the degree of grinding of the fibrous mass and the length of the fiber, as well as the physical and mechanical characteristics of the finished castings, which include the breaking length of the paper, the number of double folds and the tear resistance index. The grinding was carried out on a semi-industrial disc mill using a combined grinding set. For comparison, wavy and conical grinding cavities with straight unidirectional knives were selected. It was revealed that the wave-shaped grinding cavity has higher quality indicators in comparison with the conical grinding cavity by the nature of the impact on the fibrous mass.