Method of manufacturing porous ceramic products by reacting flue gas dust and filter dust with clays or the like, such as expanded clay

Abstract

A method for manufacturing porous ceramic products by mixing ceramic material with a fly dust containing silica and metal oxides and having a large specific surface area of at least 20 m.sup.2 /g. The mixture is heated to at least 800.degree. C to convert it into a porous ceramic material. The process is carried out so as to result in either products having mainly closed pores by heating at sintering temperatures or products having mainly open pores by heating at consolidation temperatures. The admixture may be wrapped in a sheet of material which upon heating the admixture to form pores in the material encloses the gases formed at low temperatures but which ruptures at high temperatures to expose the clay to an oxidizing atmosphere.

Dependencies are inferred from the claim text.