The aim of the study was to determine the effects of disrupting strips on the drying sewage sludge process. The research was carried out for four cases: without strips, three strips on the circumference of the drum and one central strip arranged horizontally and vertically. Due to the loosening of the bed at low velocity preferred is use of three strips situated on the circumference of the drum, which reduces drying time. Using one strip in the central part of the drum is not effective - there is no increased degree of bed relaxation. The experimental and calculated results from the models available in the literature for characteristic rotational velocity were compared. The biggest distinction was observed for centrifuging - 24.2 rpm and the smallest for critical velocity - 1.4 rpm.