Abstract: A porous silicate granular material, especially as aggregate for the production of construction materials such as lightweight concrete, mortar or heat-insulating plaster containing glass and a glassy crystalline component comprising 45 to 85 wt. % SiO2, 5 to 20 wt. % alkali oxide, 5 to 30 wt. % alkaline earth oxide and 2 to 30 wt. % of other oxides such as Al2 O3 and/or Fe2O3. The glassy crystalline component accounts for 5 to 75 wt. % of the granular material. The glassy crystalline component of the granular material is a sinter reaction product. There is also a method of producing such a granular material in which the mixture is agglomerated at a temperature of 20° C. to 150° C. at normal pressure with the water vapour partial pressure being adjusted, selected or controlled as a function of time-temperature and carbon dioxide being excluded or admitted, whereby the admission of carbon dioxide is controlled by adjusting or selecting the carbon dioxide partial pressure.

Abstract: The invention relates to a porous silicate granular material, especially as aggregate for the production of construction materials such as lightweight concrete, mortar or heat-insulating plaster containing glass and a glassy-crystalline component comprising 45 to 85 wt. % SiO2, 5 to 20 wt. % alkali oxide, 5 to 30 wt. % alkaline earth oxide and 2 to 30 wt. % of other oxides such as Al2O3 and/or Fe2O3, whereby the glassy crystalline component accounts for 5 to 75 wt. % of the granular material. The glassy crystalline component of the granular material according to the invention is the sinter reaction product of a mixture of quartz powder and/or another essentially pure fine-grained SiO2 carrier, a powdered clay and/or powdered clay mineral, Portland cement, caustic soda and an expanding agent as least one additive.

Abstract: The present invention is directed to an apparatus and process for the ion change hardening of glassware by passing the glassware through a stream of molten salt. The glassware may be arranged at different levels on a conveying means, provided with perforations to allow the molten salt to fall from level to level from an overhead salt distributor. The glassware may be positioned on a horizontally spinning rack so that molten salt continuously fills up and empties from the glassware. The molten salt is recycled from the bottom of the apparatus and may be replenished by adding salt to the recycle stream.