Combustion apparatus for burning two or more kinds of fuel simultaneously or alternatively, at least one kind of fuel being fluent; Combustion apparatus characterized by the shape of the combustion chamber; Disposition of burners with respect to the combustion chamber or to one another; Mounting of burners in combustion apparatus; Combustion apparatus characterized by the combination of two or more combustion chambers; Air-supply arrangements; Combustion apparatus with arrangements for recycling or recirculating combustion products or flue gases; Fluidized bed combustion apparatus.
