Abstract: Calcination of one of the volatile compounds is brought about in a first contacting column, in which the material is driven and put into suspension by an oxidizing gas stream, while being brought therein to a sufficiently high temperature, and the gaseous products desorbed in this first column are re-adsorbed by cooling in a second contacting column.This process applies principally to the regeneration of particles of alumina which have absorbed tars and compounds containing fluorine.

Abstract: A dust separator which has an inlet enclosure having an inlet for dust-laden gas, an outlet enclosure having side walls and connected to a pipe for discharging the dust-freed gas, a separating wall separating the inlet and outlet enclosures, several elongated filtering elements disposed in the inlet enclosure, each element having a longitudinal axis and an opening at the end emerging into the outlet enclosure, and at least one nozzle having an orifice which has an axis for blowing counter flow declogging gas into the outlet enclosure and into the filtering elements. The axis of the nozzle orifice is directed transversely to the axes of the filtering elements and obliquely to the surface of one of the side walls of the outlet enclosure.

Abstract: A filter bag for a filter system, comprising a number of parallel channels embodied by interconnecting, along parallel assembly lines distributed over pocket length, two opposite side walls of the pockets. The side walls meet at the open end of the pocket; a frame is introduced into each channel, the frame having two substantially parallel members which extend in a plane perpendicular to the main direction of the pocket, such plane being equidistant from the two assembly lines forming the lateral boundaries of the particular channel concerned. At the bottom bag end near the bag end remote from the open end of the bag, the two substantially parallel members meet by way of a bottom member which is substantially perpendicular to the plane of the two substantially parallel members - that is which extends substantially in the main direction of the bag.

Abstract: Flow divider for a powdery material, comprising a vertical duct supplied with said material. A knife with a separating upper edge is provided at the outlet of said duct to divide the inflow of said material into two outflows. At least one straight air passage is provided, lateral with respect to the vertical axis of the knife, between the inlets of two eduction chutes for said outflows. The level of said air passage is notably below that of said separating upper edge of the knife.