Abstract: The furnace according to the invention makes it possible to continuously vitrify and/or densify toxic materials, such a nuclear waste, by using microwaves. The furnace contains two vertical ends connected by a horizontal melting vessel. The materials to be melted and the microwaves are introduced at the first end. The melting vessel has a constant cross-section as a result of a horizontal upper wall in order to aid the distribution of the power of the microwaves over the surface of the molten bath. Preferably, the second end is provided with a piston making it possible to regulate the return of non-absorbed microwaves.

Abstract: An incineration apparatus is provided, preferably of the thermal heat regeneration type, in which noxious or other gases are passed to an incineration chamber, to be burnt at a sufficiently high temperature that they are disposed of, and in doing so, pass through heat-exchange beds of elements such as stones or the like, whereby the direction of gas flow may optionally be reversed. The stoneware beds reside in recovery chambers adjacent but contiguous with the combustion chamber, separated therefrom by built-up refractory blockwalls. The walls are of arcuate configuration and support the heat-retention elements in the recovery chambers. The walls are generally the thickness of a single refractory block, and are of a radius that is less than any radius of the combustion chamber and are of a sufficient radius such that the forces of the stone or other heat-retention elements outside the walls may be resisted to prevent wall collapse.

Abstract: A refractory brickwork wall having an opening therethrough has incorporated therein, at a position above the opening, a relief brickwork configuration in the form of a gable or roof. The relief brickwork includes a plurality of relief bricks each having an upper inclined surface, a lower inclined surface and a lower, generally horizontal step surface. The relief bricks are arranged one above the other in an inclined formation with the lower inclined surface of the upper relief brick of each pair of adjacent relief bricks resting on the upper inclined surface of the lower relief brick of such pair of adjacent relief bricks, and with the upper relief brick of each pair of adjacent relief bricks being partially offset in a horizontal direction from the lower relief brick of such pair of adjacent relief bricks.