Abstract: A supporting matrix for catalytically active compounds, for use, for example, in catalysts for the catalytic cracking of nitrogen oxides, is constructed of a metal core (1), an intermediate layer (3) of vitreous enamel bonded onto this core, and a porous ceramic cover coating (5) applied to the vitreous enamel intermediate layer.The supporting matrix is made by dipping the metal core into a vitreous enamel slip followed by firing at 800.degree. to 900.degree. C. The enameled metal core is then fired in a second firing to form the ceramic cover coating which represents the actual support for the catalytically active compounds.

Abstract: Heat exchanging or accumulator structure for thermal transfer between gas streams in regenerative heat exchangers, especially for the transfer of heat between the boiler exhaust gases cleaned in a scrubber and the foul boiler exhaust gases being fed to the scrubber, composed of molded elements (2; 4a; 4b; 4c) of thermoplastic material selected from the group consisting of polyphenylene oxide, a copolymer of polyphenylene oxide, polystyrene, and polyblends of polyphenylene oxide and polystyrene.

Abstract: Apparatus for cleaning the heat-exchanging surfaces of the storage elements of rotary regenerative heat exchangers. The apparatus has a row of nozzles oriented substantially at a tangent and in a radially displaceable manner before the end face of the storage element (1) in the interior of the heat exchanger, which cause the cleaning material, delivered to them from a source of cleaning material, to emerge in an aimed manner onto the storage element (1). The nozzles are provided on at least two spaced-apart nozzle heads (19; 17) disposed a tube (11; 13) extending substantially radially over one half of the end face of the storage element (1), the tube being guided into the interior of the heat exchanger in a sealed manner and being movable by a drive means radially back and forth above the storage element (1). Via movable connecting means, the tube (11; 13) is connected to at least one external, stationary material line delivering the cleaning material.

Abstract: The storage material is intended for the transfer of heat between gas streams in heat exchangers, and has stick-like molded spacing elements (12) on the one hand, and a plurality of plate-like molded elements (12) of heat-resistant plastic serving as storage elements on the other, which are assembled into storage blocks. Polyetherimide is used as the material for the molded elements (10; 12), which combines sufficiently high heat resistance with resistance to aggressive chemical influences.

Abstract: Apparatus and method for cleaning the heat exchanging surfaces of the heat transfer plates of rotary regenerative heat exchangers comprising low to medium pressure gas and/or steam operated nozzles of the injection type having injection tubes for moving by suction ambient heat exchanging gas or air into the interspaces between the heat transfer plates. The nozzles may be designed as supersonic nozzles, especially Laval nozzles.

Abstract: Apparatus for cleaning the heat exchanging surfaces of the heat transfer plates of rotary regenerative heat exchangers by using a row of high pressure directional jets of cleaning fluid directed into the interspaces between the plates and hitting deposits positioned in the interspaces essentially in the shape of a moving row of impact points.