Abstract: A method for melting thermosplastic material is disclosed. A protective liner for the interior of the furnace protects the refractory walls of the furnace from corrosion caused by the molten thermoplastic material. The improvement comprises confining a thermoplastic material between the liner and the refractory walls which is a viscous material such that its characteristics closely match those of a refractory composition.

Abstract: A process and apparatus for reducing the particulate emissions in exhaust gases for a glass melting furnace. This invention also may preheat glass batch to be charged to the furnace. An electrical charge is used to collect particulate from the exhaust gases and deposit them on oppositely charged solids. The counterflow of exhaust gases past the solids heats the solids for further processing resulting in the conservation of heat.

Abstract: A process for the manufacture of glass is disclosed. Glass batch agglomerates are formed, fed to a vertical bed preheat hopper, dried and preheated with furnace exhaust gases, and then fed to a glass melting furnace. The spent exhaust gases are electrically charged and passed through an electrified bed of granules to remove glass batch particulate from the spent gases.

Abstract: Volatile borates and/or fluorides are removed from the hot stack gases of a glass furnace by passing the hot stack gases up through a layer of wet pellets containing ions of an alkaline earth metal or an alkali metal. The pellets may contain solid borates and/or fluorides as part of the feed to the glass furnace, and still absorb volatile materials from the stack gases, so long as the borates and/or fluorides in the pellets are in, or are converted to a less soluble and volatile form that are the volatile materials in the stack gases. Ca(OH).sub.2 is a preferred material for converting the volatiles into an essentially nonvolatile form. Ion exchange materials, such as clay, can also be used to capture these volatiles.

Abstract: An improved method of preparing a molten glass composition is presented. The constituents of the molten glass composition are classified into two or more melting groups according to mutual melting properties or characteristics such as volatility, corrosiveness or fusion point. Of the constituent groups one is selected and prepared as a molten base glass composition into which the remaining groups are sequentially introduced and homogenized into the base glass forming a molten glass composition of desired forming characteristics.

Abstract: Boron and/or fluorine values are reclaimed from a boron and/or fluorine laden gas stream emanating from a glass melter by means of a preheating bed of glass-forming batch agglomerates. The boron and/or fluorine values in such gases are first reacted with a boron and/or fluorine reactive material and the gases then conveyed into such a preheating bed to separate at least a portion of the reaction products.

Abstract: An improvement is provided in glass manufacturing processes of the type wherein combustion products are passed upwardly and in countercurrent flow through a bed of gravitationally downwardly moving agglomerates of glass forming batch constituents. The improvement resides in utilizing excess sensible heat in the combustion products by passing raw colemanite through such a bed in indirect heat exchange contact with the combustion products so as to heat such colemanite to a temperature in excess of that needed to release its chemically bound water and then employing such colemanite as a batch ingredient.

Abstract: A glass melting furnace in which glass can be heated by sources below its upper surface, as electrically by Joule effect, and by means above its upper surface, as by fossil fuel firing or by heat reflectors. A cold top melting mode is employed in the charging region of the furnace while the glass discharge region maintains an exposed molten, upper surface on the glass. In a disclosed embodiment a high crown over the charging region enables cold top melting and refining to be accomplished by Joule effect while flues and burner ports in that region are closed. A low crown, which may be adjustable in its height above the glass line, is provided over the discharge region to increase heating at the exposed, molten upper surface of the glass by reflection. Heating in the discharge region can be augmented by above surface heaters distributed across the crown. A flue in the discharge region carries gases from that region.

Abstract: Method and apparatus are presented for thermally intermixing, blending and homogenizing additive constituents into a molten host glass composition as it flows through a forehearth channel. The additive composition in solid or molten form, is introduced into a thermally rising flow of molten host glass and thermally intermixed therein by successive descending and rising thermal currents.

Abstract: An electrically-heated, glass-melting furnace has an infrared-absorbing material located along the side walls to intercept energy from the heat source in the pool of molten glass in the furnace and thereby enable the side walls to be at a lower temperature. The furnace is heated electrically by means of electrodes immersed in the molten glass and with this arrangement, the glass and the side walls of the furnace tend to be at higher temperatures than furnaces utilizing fuel-fired burners firing above the molten glass. The higher wall temperatures result in a shorter life for the furnace, requiring more frequent, costly rebuilding. To overcome this, a material capable of absorbing infrared rays is supplied to the furnace along the side walls thereof. This material forms a curtain disposed between the side walls and the heat source to intercept the infrared rays and thereby reduce the operating temperatures of the side walls.

Abstract: Electrical erosion of refractory in a tank of a furnace for melting thermoplastic materials is reduced by orienting electrodes employed in Joule effect heating of the thermoplastic to limit the current density in the refractory. High electrical resistivity of certain thermoplastics tends to cause a flow of shunted current in relatively low electrical resistivity refractory of the furnace walls during Joule effect heating. Inter electrode spacing and electrode to furnace wall spacing is arranged according to the relative electrical parameters of the furnace system to achieve sufficient Joule effect heating of the thermoplastic without appreciable electrical corrosion. The effects of three phase power sources with various connections is disclosed.