Treating glass cullet to remove paper, plastic and low m.pt. metal contaminants - by heating cullet to specified temp. range in order to burn off or melt contaminants from molten clinker

摘要

The clinker is subjected to a treatment temp. of between 300 and 400 deg.C for sufficient time to burn off the accompanying paper and plastic materials and to melt any low melting point metals that can be separated from the clinker in the molten state. Also claimed is a device for the application of this method and consists of a treatment chamber of great height through which the combustion gases pass from the bottom to the top. It is equipped in its upper part with some means for introducing the clinker and incorporates in its lower part some means (4) for submitting the clinker to the above temp. and for separating the molten metals produced. USE/ADVANTAGE - Used for the treatment of clinker contg. broken glass emanating from the recovery of used bottles, in order to eliminate the accompanying paper labels as well as any plastic materials or low melting point metal such as lead and tin which are present in the capsules of the bottles. The method also incorporates screens to remove fine materials thus allowing the prodn. of a clinker that can be used directly in a glass melting furnace. The method is less costly and more efficient than conventional water cleaning methods used for these purposes.