Our STAG Impact Mill PM has been specially developed for breaking up nodulized bulk material. This application is mainly employed in the treatment of boiler ash from incineration plants. By means of the variably adjustable impactor of the STAG Impact Mill PM, the bulk material is broken up to adegree of granulation suitable for pneumatic conveyance. This is a prerequisite for guaranteeing a high degree of functional safety in pneumatic conveyance, even for critical bulk materials.