The invention Described is a device (1) for dividing a stream of particulate or pulverulent material into at least two substreams. The device has a housing (2) with a substantially vertical inlet duct (3) and two or more outlet ducts (4, 5, 6, 7) emanating from separate openings, and being separated by partition walls (9) extending radially relative to the centreline of the inlet duct (3). The device also has a rotor 11) which is located in immediate extension of the inlet duct (3), with its axis of rotation coinciding with the centreline (10) of the inlet duct. The rotor (11) has a radially configured surface (11a) for directing the falling material stream radially outwards into the free space (12) above the outlet ducts. The device is peculiar in that the radial partition walls (9) can be adjusted in the circumferential direction. The result will be a freely variable ratio between an arbitrary number of outlet substreams.