Falling impact as an isolated disintegration mechanism in drum pulping for packaging board

Falling impact is one of the main mechanisms in the disintegration of packaging board in a drum pulper. In this study, the disintegration effect of falling impact was studied and evaluated with three different materials. Impact disintegration was isolated with a designed device that simulates falling in drum pulping. The falling heights studied were 2.75 m and 3.75 m. Repeated impacts from both of the studied distances were found to be similarly efficient at disintegrating a weaker material, such as testliner. This kind of behavior proposed that every material has an optimal falling height, from an energy consumption perspective. Another way to increase falling impact is to increase the mass of falling pulp. It was found that it is possible to increase the efficiency of the disintegration of stronger materials, such as kraftliner, with an increased falling mass. It was also noticed that motion after impact is important for disintegration as well. The number of impacts needed to disintegrate packaging board was found to be high. This raised the question of whether or not the falling of pulp is the only method for disintegrating packaging board. The results suggest that impacts by falling alone are not enough for the thorough disintegration of packaging board material; rather, other mechanisms are also involved.