The invention relates to a process for the preparation of a glass-ceramic blank for dental purposes with lithium silicate as crystal phase, in which lithium silicate blanks that are no longer required and in particular residues thereof are used as starting material and which allows the production of a homogeneous starting glass within a short time.

An apparatus for the wet attrition of particulate material comprising an attrition scrubber; a dewatering screen comprising a deck and a sump beneath the deck, the dewatering screen being mounted upstream of the attrition scrubber whereby oversize material from a downstream end of the deck of the dewatering screen passes into the attrition scrubber; and a hydrocyclone wherein an underflow, containing a coarser fraction of the feed slurry, passes out of a lower outlet of the hydrocylone while an overflow, containing a finer fraction of the feed slurry and most of the water, passes out of an outlet at the upper end of the hydrocyclone, a pump being provided for pumping material from the sump of the dewatering screen to the inlet of the hydrocyclone, wherein the underflow from the hydrocyclone is passed into the attrition scrubber.

The present invention relates to the methods of recycling electrochromic devices and also designing such devices while keeping recyclability in perspective. Recyclability includes recovering of certain materials for re-use within the same application or other applications. Using recycling reduces or eliminates waste stream quantities to be disposed of and/or reduces toxicity of these waste streams.

A glass/quartz composite structure comprises quartz grit, quartz powder and glass grit wherein the glass grit is in an amount greater than 50% by weight of the composite structure, and a binding resin. The glass/quartz composite structure may be formed into a 1.2-1.5 cm thick slab for countertops using standard cabinet perimeter support. The slab may be made by mixing the quartz grit, the quartz powder, the glass grit, and the binding resin, pouring the mixture in a mold, and compacting the mixture in the mold. Specific natural mineral components may be added to the glass/quartz/resin composite structure to provide aesthetics of specific natural stones.

A glass/quartz composite structure comprises quartz grit, quartz powder and glass grit wherein the glass grit is in an amount greater than 50% by weight of the composite structure, and a binding resin. The glass/quartz composite structure may be formed into a 1.2-1.5 cm thick slab for countertops using standard cabinet perimeter support. The slab may be made by mixing the quartz grit, the quartz powder, the glass grit, and the binding resin, pouring the mixture in a mold, and compacting the mixture in the mold. Specific natural mineral components may be added to the glass/quartz/resin composite structure to provide aesthetics of specific natural stones.

Methods have been developed to produce amorphous silica materials including, but not limited to, glass, container glass, fiber glass, glass bead, sheet or plate glass, glass aggregate, glass sand, abrasives, proppants, foamed glass, and manufactured glass articles. The initial processing steps include preparing a melt batch comprising at least one silica containing component and other processing or product enhancing components, melting the melt batch, and cooling the melted melt batch. The batches include high concentrations of metal oxides, slags, combustible materials, limestone, other product or process enhancing compounds and combinations thereof.

Glass melting process including the introduction of a vitrifiable solid charge into a furnace, heating and melting of charge thereby obtaining molten glass. Discharging the molten glass from the furnace and discharging a CO.sub.2-containing gaseous effluent from the furnace. The charge having at least one carbonate undergoing a dissociation reaction and releasing gaseous CO.sub.2 when heated and melted. The gaseous effluent discharged from the furnace being used to produce, at least one additive in the form of an alkali metal or alkaline earth metal carbonate, at least a part of which is incorporated in the charge which is introduced into the furnace.

There is disclosed an antibacterial glass composition, a preparing method of an antibacterial glass coating film using the same and an electric home appliance including the same. The antibacterial glass composition according to the present disclosure and the antibacterial glass coating film using the same are applied to an electric home appliance, thereby exhibiting excellent antibacterial properties and heavy metal elution safety, and exhibiting excellent transmittance (70% or more) when applied to a transparent glass substrate.

There is disclosed an antibacterial glass composition, a preparing method of an antibacterial glass coating film using the same and an electric home appliance including the same. The antibacterial glass composition according to the present disclosure and the antibacterial glass coating film using the same are applied to an electric home appliance, thereby exhibiting excellent antibacterial properties and heavy metal elution safety, and exhibiting excellent transmittance (70% or more) when applied to a transparent glass substrate.

A method for producing a low iron silica sand product suitable for glass production has an SiO.sub.2 content of at least 99.8% by weight, an Fe.sub.2O.sub.3 content of less than 0.008% by weight, an Al.sub.2O.sub.3 content of less than 0.1% by weight, and a CaO content of less than 0.05% by weight includes preparing a slurry of crude ore, wherein the crude ore has a sand content of about 75% to 80% by weight, a kaolin/mica content of about 15% to 25% by weight, a dark, heavy mineral content of about 1% by weight, and an Fe.sub.2O.sub.3 content of about 0.5% to 1.0% by weight. Particles having a size of less than about one hundred forty mesh are removed, and contaminant material is removed. The sand is then separated from the slurry, dried, and passed through a rare earth magnetic separator.