Concrete may be melted to form a glass product. Methods and batch compositions including concrete may be used to produce amorphous silica materials including, but not limited to, glass, container glass, fiber glass, glass bead, glass spheres, 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 concrete and, optionally, other components, melting the melt batch, and cooling the melted melt batch. Further processing steps may be utilized to produce the glass article.

Disclosed herein is a method for preparing a matrix for vitrifying radioactive waste, including: grinding natural magmatic rocks; and melting the ground product at 1450-1500 C. for 3-4.5 h followed by moulding and annealing to produce the matrix. The matrix includes 45%-65% by weight of SiO.sub.2, 9%-18% by weight of Al.sub.2O.sub.3, 4%-12% by weight of CaO, 3%-10% by weight of MgO, 6%-16% by weight of Fe.sub.2O.sub.3+FeO, 2%-9% by weight of Na.sub.2O+K.sub.2O and 1%-5% by weight of TiO.sub.2. The matrix is doped with simulated radioactive waste, ground, melted, moulded and annealed to obtain a glass wasteform with good chemical and thermal stability.

A furnace system includes a mixing chamber that receives separate streams of raw material and cullet mix and discharges a combined stream. The mixing chamber tapers from an inlet end to an outlet end. One inlet in the inlet end is configured to receive one of the material and mix and is aligned with an outlet in the outlet end along a vertical axis. Another inlet is configured to receive the other of the material and mix and is offset from the outlet relative to the vertical axis such the material or mix is deposited on a sidewall of the tapered chamber before reaching the outlet. A charger receives the combined stream from the mixing chamber and discharges the mixture into a molten bath in a furnace. A duct system may be used to mix exhaust from the furnace with exhaust from the mixing chamber and charger.

Various embodiments of the present disclosure can include at least one of a method, apparatus and system for the efficient melting of a feedstock to at least one of a molten and vitrified state to be used in a manufacturing system comprised of: a melter to which the feedstock is provided; and a heat recovery system configured to capture exhaust waste heat produced by the melter, wherein the heat recovery system transfers an energy recovered from the exhaust waste heat to pre-heat the feedstock provided to the melter.

A method for processing cullet includes detecting a plurality of types of glass contained in the cullet using colorimetry, calculating a quantity of different types of glass detected in the cullet, determining a quantity of oxide and/or a redox potential which are associated with the cullet depending on the quantity of the different types of glass detected in the cullet.

An apparatus for the gasification and vitrification of waste comprises a plasma arc furnace provided with two movable graphite electrodes. The furnace includes an air-cooled bottom electrode adapted for transferring the current through a slag melt. The furnace is entirely sealed and is also provided with gas tight electrode seals adapted to control reducing conditions inside the furnace. An electrical circuit is further provided, which is adapted for switching from transferred io non-transferred modes of heating, thereby allowing the furnace to be restarted in case of slag freezing.

A method of making a hollow container-shaped glass article composed of soda-lime-silica glass includes forming a particulate feedstock comprised of pulverized soda-lime-silica cullet particles into a hollow monolithic glass container preform without melting the cullet particles. The hollow monolithic glass container preform has a container shape that includes a wall defining an interior containment space and an opening to the interior containment space and, upon formation, has a temperature above the glass transition temperature of the soda-lime-silica glass. The hollow monolithic glass container preform is eventually cooled into a hollow, amorphous soda-lime-silica glass article, such as a partially-formed container or a finished container, that retains the previously-established container shape.

A sealing system for isolating the environment inside a vitrification container from the outside environment comprises a vitrification container with a lid. The lid comprises two or more electrode seal assemblies through which two or more electrodes may be operatively positioned and extend down through the lid into the vitrification container. The electrodes may move axially up and down through the electrode seal assemblies or lock into place. The electrode seal assemblies each comprise a housing having two halves with recessed ring grooves. Sealing rings with a split may be placed into the grooves. Gas galleries may be machined or cast into the housing such that they are adjacent to the ring grooves. The gas galleries distribute gas onto the external faces of the sealing rings causing a change in pressure resulting in the sealing rings compressing onto the electrodes and forming a seal.

Process for confinement of waste containing at least one chemical species to be confined, by in-can vitrification in a hot metal can into which waste and a vitrification additive are added, the waste and the vitrification additive are melted to obtain a glass melt which is then cooled, characterised in that at least one oxidising agent is also added into the metal can and in that the concentration of oxidising agent(s) expressed as oxide(s) in the glass melt is between 0.1 and 20% by mass, preferably 4 and 20% by mass, even more preferably 5 and 15% by mass, and even more preferably 10 and 13% by mass of the glass melt mass.

The present invention relates to a method for producing mineral material suitable for use as raw material in a glass melting method, comprising: supplying a main tank with a vitrifiable mixture of materials comprising recycling materials comprising organic matter; melting the vitrifiable mixture of materials in the main tank using submerged burners to obtain a melt; and introducing a solid oxidant into the melt.