The article describes the process of cleaning dusty gases. Attention is paid to the devices for fine cleaning of dusty gases. Attention is focused on the fact that the most simple and, at the same time, effective dust cleaning device is a granular filter. Its advantage is shown when cleaning dusty air from very aggressive devices, when working on high-temperature and aggressive gases. The prospects of granular filters, in which a cement clinker is used as a filter material, with a granule size of up to 10 mm, are shown. The main causes of dust deposition on grains, filaments or fibers are presented. Various approaches to determining the empirical dependences of the dust span on the design parameters of the filter apparatus are presented. The criterion dependence of the cement dust span is presented, which approximates the results of the experiment. It allows you to determine the efficiency of the granular filter from its design and technological parameters.