Abstract: The invention relates to a material feeding system (1) for a melter comprising: (i) a substantially horizontal feeding barrel (5) designed to feed solid material through the melter wall (9) into the melt (11) contained in the said melter, and arranged below the level (13) of the melt (11) contained in the melter (30), (ii) said feeding barrel (5) comprising a material input opening (15) and material output opening (17), the material output opening (17) leading into the melt (11) contained in the melter (30), said feeding barrel (5) comprising an internal feeder (20) designed to push solid material (7) loaded through the material input opening (15), in the direction of the longitudinal barrel axis (6) toward the material output opening (17), the end of the internal feeder (20) on the material output side extending at a minimum at a distance from the internal melter surface (19) of two (2) to ten (10) times the diameter of the feeding barrel (5), preferably three (3) to eight (8) times the diameter of the feedi

Abstract: A method includes electrolyzing water into hydrogen, combining the hydrogen with nitrogen to generate forming gas, delivering the forming gas to a reducing environment zone, and processing an intermediate material into a product material in the reducing environment zone. The step of processing the intermediate material into the product material may include processing a glass melt into a float glass ribbon on a tin melt and then cooling the float glass ribbon into sheet glass.

Abstract: The present disclosure relates to an apparatus and method for cleaning an edge director, and more particularly, to an edge director cleaning apparatus that includes two or more nozzle pipes arranged to be parallel to each other, nozzle tips respectively provided at first ends of the two or more nozzle pipes, fuel manifolds respectively connected to second ends of the two or more nozzle pipes, and a fixing guide configured to fix the nozzle pipes, wherein the nozzle tips extend in an oblique direction with respect to an extending direction of the nozzle pipes. When the apparatus and method for cleaning an edge director according to the present disclosure are used, devit can be safely removed without damage to the apparatus while reducing downtime.

Abstract: Described herein are alkali-free, boroalumino silicate glasses exhibiting desirable physical and chemical properties for use as substrates in flat panel display devices, such as, active matrix liquid crystal displays (AMLCDs) and active matrix organic light emitting diode displays (AMOLEDs). In accordance with certain of its aspects, the glasses possess good dimensional stability as a function of temperature.

Abstract: A method of reducing bubble lifetime on the free surface of a volume of molten glass contained within or flowing through a vessel including a free volume above the free surface, thereby, minimizing re-entrainment of the bubbles back into the volume of molten glass and reducing the occurrence of blisters in finished glass products.

Abstract: A composition for glass, alkaline earth aluminosilicate glass, and a preparation method therefor and applications thereof. Based on the total number of moles of each component and the counting of oxides, the composition contains 68-73 mol % of SiO2, 11.5-15 mol % of Al2O3, 2-6 mol % of MgO, 2.5-7.5 mol % of CaO, 0-3 mol % of SrO, 2-7 mol % of BaO, 0-4 mol % of ZnO and 0.05-1.5 mol % of TiO2. The glass has a high strain point, a high Young's modulus, a high specific modulus, a high Vickers hardness, high chemical stability, a high refractive index and high glass formation stability, and has a lower forming temperature, a lower melting temperature, a lower thermal expansion coefficient, a lower surface tension, a lower density, and low glass manufacturing difficulty.

Abstract: A method of reducing the volume of float bath atmosphere lost from an opening in the exit end of the float bath is described. The method comprises directing a first jet of fluid having a first jet velocity followed by a second jet velocity towards a plane a conveyance for a float glass ribbon. An obstruction in the path of the first jet of fluid causes the jet to change from the second to a third jet velocity. The obstruction may be a portion of a roller positioned outside the opening or a float glass ribbon that has been formed on a surface of molten metal contained in the float bath that has subsequently been transferred through the opening. A float bath having sealing means to reduce atmosphere loss from an exit of the float bath is also described, as is an assembly useful in carrying out the aforementioned methods.

Abstract: The invention relates to a cooling device (100) for cooling at least one element (150, 151) passing through said device, comprising a metal block (115), having a first side and a second side, and comprising a cooling channel (130) for cyrogenic gas. The at least one element (150, 151) can be guided along the sides of the first side of the metal block (115), the cooling channel (130) is at least partially in heat conductive connection with the second side of the metal block (115), and the cooling channel (130) has an attachment (131) on a first end for the entry of cryogenic gas and an attachment on a second end for the exit of cryogenic gas. The invention also comprises a hardening device having such a cooling device (100) and a method for cooling at least one element (150, 151) passing through said device.

Abstract: A glass manufacturing apparatus comprises at least one nozzle facing a conduit and extending transverse to a travel path defined by the conduit. The at least one nozzle is configured to cool molten material within the interior of the conduit with a stream of cooling fluid forced against an exterior of the conduit along a cooling axis extending transverse to the travel path defined by the conduit. In further examples, methods of processing molten material includes cooling the molten material within an interior of a conduit by forcing a stream of cooling fluid against an exterior of the conduit along a cooling axis extending transverse to a travel path defined by the conduit.

Abstract: A method for producing rod lenses with an enveloping diameter of the rod lens face of up to 200 mm and an edge length of at least 800 mm. The method is characterized in that fabrication is performed from a cylindrical rod lens element made from synthetic quartz glass material configured as a fused silica ingot. This is performed using a flame hydrolysis method with a direct one stage deposition process of SIOx particles from a flame stream onto die that rotates and is moveable in a linear manner with respect to the flame stream.

Abstract: The present invention relates to a float glass for chemical strengthening, containing a bottom surface coming into contact with a molten metal at the time of forming and a top surface opposing the bottom surface, in which a difference ?(N—Na2O2) determined by subtracting a square of a normalized Na2O surface concentration of the bottom surface which is a value obtained by dividing an Na2O concentration in the bottom surface by an Na2O concentration at a depth position of 100 ?m therefrom, from a square of a normalized Na2O surface concentration of the top surface which is a value obtained by dividing an Na2O concentration in the top surface by an Na2O concentration at a depth position of 100 ?m therefrom, is 0.040 or less.

Abstract: The present disclosure discloses a float bath that may enhance spreadability of a poured glass melt when pouring the glass melt, an apparatus for manufacturing a float glass comprising the same, a method for manufacturing a float glass using the float bath, and a float glass produced by the method. The float bath according to the present disclosure receives a metal melt and allows a glass melt poured onto the metal melt to float and move from upstream to downstream, and includes a guiding unit provided at a part where the glass melt is poured, to come into contact with the side of the poured glass melt to guide a sidewise spreading path of the glass melt to expand sidewise spreading of the glass melt.

Abstract: An apparatus includes a susceptor and a protective pipe. A gas containing 50% or more of argon or nitrogen is used as a gas to be supplied into the susceptor. The protective pipe has a heat insulating region (17a) enclosed with a heat insulator (18) with a length of Db (mm) at the upper section thereof and a non-heat insulating region (17b) not enclosed with any heat insulators at the lower section thereof. The temperature of the glass fiber at the outlet of the protective pipe becomes 1700° C. or less. The outer diameter of the glass fiber at the outlet of the protective pipe is within a range of the target outer diameter of the glass fiber+6 ?m or less.

Abstract: Titania-doped quartz glass is manufactured by mixing a silicon-providing reactant gas and a titanium-providing reactant gas, preheating the reactant gas mixture at 200-400° C., and subjecting the mixture to oxidation or flame hydrolysis. A substrate of the glass is free of concave defects having a volume of at least 30,000 nm3 in an effective region of the EUV light-reflecting surface and is suited for use in the EUV lithography.

Abstract: Ion transport membranes are integrated with a glass melting furnace and a float glass bath. Only feeds of air, steam and hydrocarbon are necessary for producing hot oxygen for the melting furnace and a mixture of nitrogen, carbon dioxide, and hydrogen for the float glass bath.

Abstract: Methods and systems for controlling bubble size and bubble decay rate of glass foams formed during submerged combustion melting. Flowing a molten mass of foamed glass comprising molten glass and bubbles entrained therein into an apparatus downstream of a submerged combustion melter. The downstream apparatus has a floor, a roof, and a sidewall structure connecting the floor and roof. The foamed glass has glass foam of glass foam bubbles on its top surface, and the downstream apparatus defines a space for a gaseous atmosphere above and in contact with the glass foam. The downstream apparatus includes heating components to heat or maintain temperature of the foamed glass. Adjusting composition of the atmosphere above the glass foam, and/or contacting the foam with a liquid or solid composition controls bubble size of the glass foam bubbles, and/or foam decay rate.

Abstract: The present invention relates to a glass melting furnace comprising a channel-shaped melting tank, the batch materials being introduced at an upstream end, the molten glass being recovered at the downstream end, said furnace being heated by means of burners, in which the combustion energy is produced by oxy-fuel combustion in respect of at least 65% thereof, the burners being distributed on the walls along the length of the furnace, in which flue gas discharge is mostly localized close to the upstream end near the openings through which the batch materials are introduced, the rest of the flue gas being removed close to the downstream part so as to maintain dynamic sealing with respect to the surrounding atmosphere.

Abstract: An apparatus for manufacturing 3D glass, the apparatus including: a molding part for molding a glass substrate; an assembling and disassembling part for carrying-out the molded glass substrate and replacing the molded glass substrate with an other glass substrate; and a loading part for loading the molded glass substrate is disclosed. A method for manufacturing 3D glass including: carrying-in a mold including a glass substrate into a chamber of a molding part; preheating the carried-in mold; molding the glass substrate by pressing the heated mold; cooling the molded glass substrate; and carrying-out the molded glass substrate and carrying-in an other glass substrate into the mold is also disclosed.

Abstract: A method and apparatus for manufacturing high-purity long silicon seed rods with controlled resistivity for Siemens and similar processes with using a film of silicon dioxide, wherein a film of silicon dioxide is formed on the seed rod in the course of a reaction between a silicon melt and oxygen. The rod is formed with a quartz die and cooled by direct immersion into a cooling fluid, such as de-ionized water and/or by cooling fluid vapor in the gas cooling zone.

Abstract: A substrate ion exchange system is provided for a multi-component ion exchange bath that minimizes stratification effects within the bath, along with methods of mixing such baths. The system includes a substrate having an outer region containing a plurality of substrate metal ions; an ion exchange bath with a first metal salt and a second metal salt; and a vessel for containing the ion exchange bath and the substrate. The system further includes a mixing apparatus configured to mix the bath such that the metal ion concentration associated with the first metal salt in the bath is substantially uniform within the vessel. The substrate metal ions are exchangeable with metal ions from the first and second metal salts. Further, the first and second metal salts are miscible and molten.

Abstract: A method is disclosed for scribing a contained crack or vent in a chemically strengthened glass sheet. The glass has shallow surface regions under compressive stress, bounding a central region under tensile stress. The vent is formed by rapidly bulk-heating the glass, using radiation from a carbon monoxide laser, to a depth just below a surface compressive region and extending marginally into the tensile stress region then rapidly cooling the heated region with a water mist spray. The glass sheet can be subsequently divided along the vent by application of mechanical or thermal stress.

Abstract: Provided is an apparatus for producing a sheet glass, including: a forming device that forms a glass ribbon by allowing molten glass continuously supplied onto molten metal in a bath to flow on the molten metal; a rotary roll disposed in an outer vicinity of the bath and configured to draw the glass ribbon obliquely upward from the molten metal; and a supporting device supporting the rotary roll from below.

Abstract: An apparatus for manufacturing a glass optical element includes: a heating unit that heats a glass material; a pressurizing unit that pressurizes the glass material; a cooling unit that cools the glass material; a molding room in which the heating unit, the pressurizing unit, and the cooling unit are located; an inert-gas supplying unit that forms a plurality of flows of an inert gas within the molding room by blowing the inert gas in a plurality of directions crossing each other; and an inert-gas emitting unit that emits, from within the molding room, the inert gas supplied into the molding room by the inert-gas supplying unit.

Abstract: An apparatus and method for removing volatilized chemical compounds from within enclosed or partially enclosed spaces containing molten glass. One or more condensing devices are positioned within the enclosure to produce preferential condensation of the vapor on condensing elements of the condensing devices, thereby facilitating easy removal of the condensates from the enclosure. The condensing elements may have a variety of shapes and sizes depending on the design of the enclosure.

Abstract: Methods and systems for controlling bubble size and bubble decay rate of glass foams formed during submerged combustion melting. Flowing a molten mass of foamed glass comprising molten glass and bubbles entrained therein into an apparatus downstream of a submerged combustion melter. The downstream apparatus has a floor, a roof, and a sidewall structure connecting the floor and roof. The foamed glass has glass foam of glass foam bubbles on its top surface, and the downstream apparatus defines a space for a gaseous atmosphere above and in contact with the glass foam. The downstream apparatus includes heating components to heat or maintain temperature of the foamed glass. Adjusting composition of the atmosphere above the glass foam, and/or contacting the foam with a liquid or solid composition controls bubble size of the glass foam bubbles, and/or foam decay rate.

Abstract: Apparatus including a flow channel defined by a floor, roof, and sidewall structure connecting the floor and roof. One or more combustion burners is positioned in either the roof, the sidewall structure, or both, and transfer heat to a molten mass of glass containing bubbles having a bubble atmosphere flowing through the flow channel. The burners contribute to formation of a channel atmosphere above the molten glass. Apparatus includes a device, at least a portion of which is positionable under a level of the molten glass in the flow channel, configured to emit a composition into the molten glass under the level to intimately contact the composition with the molten glass and bubbles therein. The composition diffuses into the bubbles to form modified atmosphere bubbles sufficiently different from the channel atmosphere to increase diffusion of a species in the channel atmosphere into the modified atmosphere bubbles.

Abstract: The device for manufacturing glass, in which bubble formation on precious metal components is prevented, has a precious or refractory metal wall (12, 43) at least partially surrounding a glass melt from which the glass is made, a first electrode pair (20, 21) for measuring oxygen partial pressure at an interface between the glass melt and the wall to obtain an actual value, a second electrode pair (12, 43, 20) for measuring an oxygen partial pressure in the glass melt to obtain a set point value and a regulating system (39, 45) for adjusting the oxygen partial pressure at the interface according to a comparison between the actual value and the set point value, so that the oxygen partial pressure at the interface is within a safe range.

Abstract: An apparatus and method for removing volatilized chemical compounds from within enclosed or partially enclosed spaces containing molten glass. One or more condensing devices are positioned within the enclosure to produce preferential condensation of the vapor on condensing elements of the condensing devices, thereby facilitating easy removal of the condensates from the enclosure. The condensing elements may have a variety of shapes and sizes depending on the design of the enclosure.

Abstract: A crucible is filled with silicon material and is arranged in a process chamber. The silicon material in the crucible is melted and is subsequently cooled below the solidification temperature. During a time period, a plate element that has at least one passage may be arranged over the molten silicon in the crucible, and a gas flow may be directed onto the surface of the molten silicon at least partially via the at least one passage. Alternatively a crucible arrangement includes a crucible and a holding ring arranged on or above a crucible filled with silicon material. Additional silicon material may be received and held above the crucible by the holding ring. During the heating of the silicon material in the crucible and the holding ring, molten silicon is formed in a crucible, which is subsequently cooled below the solidification temperature of the silicon.

Abstract: According to one embodiment, a laser annealing apparatus includes a laser device, an anneal chamber including a stage, a first housing, and an incidence window which is attached to the first housing, an optical module including a second housing and an emission window which is attached to the second housing, and a seal member which surrounds an optical path which connects a position where the emission window is attached and a position where the incidence window is attached, and effects sealing between the optical module and the anneal chamber, an inside of the seal member being an atmosphere of an inert gas.

Abstract: A sheet wafer furnace has a chamber having an opening, and a crucible, within the chamber, and spaced from the opening. The furnace also has a puller configured to pull a sheet wafer from molten material in the crucible and through the opening in the chamber, and a seal across the opening of the chamber.

Abstract: A vacuum recycling apparatus for refining solar grade polysilicon is provided which contains a vacuum degassing (VD) device and a vacuum recycling (RH) device. By storing liquid silicon in a bucket in the VD device, controlling the pressure inside the VD and RH devices, and introducing inert gas into the apparatus, the liquid silicon is stirred for the removal of impurities. With the present invention, solar grade polysilicon can be directly produced with a specified purity, significantly reducing the production time and cost.

Abstract: The regionally coated noble metal element used in glass production has an uncoated region for contacting a glass melt and an H2-impervious layer or an H2-impervious and O2-impervious layer on a side opposite from the uncoated region, which has a layer thickness ?1 mm, is heat-resistant, and is either liquid or solid. This layer is made from at least one glass or glass mixture, an at least partly crystallized glass or a ceramic material. The coated noble metal element can be a Danner channel, a Vello draw head, an A-draw head, a Vello needle, a drawdown needle, a discharge ring or a Danner blowpipe. A process for coating a noble metal element to produce the regionally coated noble metal element is also described.

Abstract: During fabrication of a vitreous silica crucible, contamination of the vitreous silica crucible due to wear particles and debris of components of an apparatus for manufacturing a vitreous silica crucible is reduced by preventing damage and wear of the components of the apparatus due to silica fume. The apparatus for manufacturing a vitreous silica crucible is divided into a lower section for accommodating a mold and a mold driving system and an upper section for accommodating an arc electrode driving system, wherein a sectioning member including one or more communication paths for allowing penetration of arc electrodes, thereby the air flow is controlled so as to reduce exchange between gas in the upper section and gas in the lower section.

Abstract: A sealing apparatus for use in conveying molten glass from a first vessel to a second vessel, wherein at least a portion of the first vessel is nested within the second vessel without contact between the first and second vessels, and a flexible member comprising a gas-tight seal separates an atmosphere enclosed by the sealing apparatus and an ambient atmosphere. The sealing apparatus is useful for flexibly sealing a non-contact joint between conduits for supplying molten glass to a forming body.

Abstract: Embodiments of a system and method for melting feedstock and casting ingots are disclosed. The system comprises a feedstock source, a stationary melting furnace, and one or more solidification modules capable of receiving molten feedstock from the melting furnace. In some embodiments, the system further includes a feed system for transferring feedstock from the feedstock source to the melting furnace. Feedstock is fed into the melting furnace and heated to produce molten feedstock. Molten feedstock flows into a solidification crucible within the solidification module. The solidification crucible is cooled to provide directional solidification and production of an ingot. The melting furnace may include a thermal valve system to prevent molten feedstock from flowing into the solidification crucible until substantially all of the feedstock within the melting furnace is molten. In some embodiments, the feedstock consists essentially of silicon and a multi-crystalline silicon ingot is produced.

Abstract: The present disclosure provides a method and apparatus for manufacturing a silicon substrate using inert gas blowing during continuous casting to provide excellent productivity and surface quality. The apparatus includes a raw silicon feeder through which raw silicon is fed, a silicon melting unit disposed under the raw silicon feeder and melting the raw silicon to form molten silicon, a molten silicon storage unit storing the molten silicon supplied from the silicon melting unit and tapping the molten silicon to provide a silicon melt having a constant thickness, a transfer unit transferring the silicon melt tapped from the molten silicon storage unit, and a cooling unit cooling the silicon melt transferred by the transfer unit. Here, the cooling unit cools the silicon melt by blowing inert gas at a rate of 0.1˜2.5 Nm3/h.

Abstract: An apparatus 10 for producing a plate glass, comprising a bath 14 for float-forming for reserving a molten metal 16 for forming a band-shaped plate glass having a predetermined thickness by feeding a molten glass ribbon 20 in a predetermined direction on the molten metal 16, and a pair of partition walls 46 provided substantially above left and right edges 22 of the molten glass ribbon 20 and substantially along the edges 22 to partition a space above a bath surface of the molten metal into an upper space A above a region covered with the molten glass ribbon 20 and upper spaces B above regions not covered with the molten glass ribbon 20; wherein the partition walls 46 each has a vertically dividable structure dividable into an upper partition wall 46A and a lower partition wall 46B, and the lower partition wall 46B is constituted by strip-shaped lower strip members 58 provided continuously to each other in a lateral direction, and the strip members 58 are configured to be removable or openable from the upper

Abstract: The present invention provides a mold for molded glass and its protection method; the protection method permits reducing gas to be generated within the mold for molded glass, thus preventing oxidation of core assembly during temperature rise of glass and protecting the core assembly; the reducing gas is formed by the reaction between oxygen and carbon-containing element in the mold; the mold comprises a core assembly, a core sleeve sleeved onto exterior of the core assembly and a reaction member, of which the reaction member made of graphite material is arranged onto exterior of the core sleeve or into the chamber of core assembly, and used to generate reducing gas from reaction with oxygen within the mold; moreover, the mold also comprises a core assembly, a core sleeve and a fixed molding ring; a carbon film is coated onto the inner side of the fixed molding ring, and the reducing gas is formed from reaction with oxygen within the mold space.

Abstract: A method for manufacturing an optical fiber preform and an optical fiber preform apparatus are provided which can reduce hydroxyl groups in an optical fiber preform to a sufficient level without requiring any special equipment or operating conditions. When an optical fiber preform is manufactured by the vapor-phase deposition method, the dehydrating treatment is performed on a porous core preform that is obtained by depositing glass microparticles. In this treatment, a dehydrating agent is supplied to a dehydration apparatus through a feeding pipe and a main feeding pipe made of a material having a water permeance factor of 1.0×10?11 g·cm/cm2·s·cmHg or less, thereby manufacturing an optical fiber preform.

Abstract: Corrosion of the inner surface of the crown of a glassmelting furnace is reduced or avoided by directing at low velocity along that surface a gaseous stream comprising water vapor, or comprising the combustion products of an oxy-fuel burner operated at a stoichiometric ratio of at least 1.0, or the combustion products of a burner operated at a stoichiometric ratio less than 1.0, or by injecting into the furnace interior a gaseous reactant which reacts with alkali species in said space.

Abstract: A method for manufacturing an optical fiber preform and an optical fiber preform apparatus are provided which can reduce hydroxyl groups in an optical fiber preform to a sufficient level without requiring any special equipment or operating conditions. When an optical fiber preform is manufactured by the vapor-phase deposition method, the dehydrating treatment is performed on a porous core preform that is obtained by deposing glass microparticles. In this treatment, a dehydrating agent is supplied to a dehydration apparatus through a feeding pipe and a main feeding pipe made of a material having a water permeance factor of 1.0×10?11 g·cm/cm2·s·cmHg or less, thereby manufacturing an optical fiber preform.

Abstract: The present invention is directed to a device and method for shaping optical components with improved uniformity and higher throughput. A curved oven provides a plurality of sequential chambers arranged in a curved path, with walls separating the chambers. The walls of the chambers may have openings shaped to match the profile of shaping molds and pedestals which are transported through the oven. An optional dual temperature control system may provide for the separate temperature regulation of upper and lower regions of the chambers. Optical components, such as for solar energy sytems, are manufactured by conveying material and molds on a transport system through the curved oven and shaping them by controlled heat and vacuum assisted slumping. The chambers may be grouped into regions, with the materials undergoing different processes as they traverse each region.

Abstract: The present invention is to provide a molten glass producing apparatus realizing simultaneously the production of a glass article of high quality and save-energy in producing molten glass, a molten glass producing method employing the molten glass producing apparatus and a method for producing a glass article. In the molten glass producing apparatus having a vacuum degassing apparatus, the melting tank is provided with a separating means for separating the area for circulating the molten glass in the melting tank into an upstream circulation flow and a downstream circulation flow, the distance from the separating means to the downstream end of the molten glass flow path in the melting tank is from 0.1 LE to 0.

Abstract: An atmosphere regulator for coating and a coating apparatus on float glass production line are disclosed. Said atmosphere regulator for coating disposed between the district of lift out rolls and the A district of annealing lehr comprises a housing where a plurality of conveyor rolls which transfer sheet glass from said district of lift out rolls to the A district of said annealing lehr are installed, a curtain, an up-turning door and down-turning door are disposed at the joint where said district of lift out rolls and A district of annealing lehr connects. Said coating apparatus comprises a plurality of parallel base boards having a slot in between of the length corresponding to the width of said sheet glass and communicated with the entrance and the exhausting chamber. The present invention has effectively solved the drawbacks occurred in prior arts such as single function for coating, limited adjusting range of film thickness and bad film quality.

Abstract: The process of making synthetic silica glass occurs in a combustion chamber of a muffle furnace. It includes producing a gas flow containing a fuel, an oxidizer, and a silicon compound that is converted by flame hydrolysis and/or by chemical oxidation to SiO2 particles, and depositing them on a target to form a roll-shaped silica glass body. The combustion chamber is provided with a gas inlet and a gas outlet arranged at opposite ends of the combustion chamber, which widens from the inlet to the outlet. The gas flow is produced by a central nozzle for the silicon compound, a first concentric ring-shaped nozzle for the oxidizer, and a second concentric ring-shaped nozzle for the fuel. The process is characterized by a ratio of areas of ring gaps of the ring-shaped nozzles of from 1:4 to 1:6.1. The apparatus for the process is also part of the invention.

Abstract: A process and device for abating air-borne particles during glass melt handling processes by using electrostatic precipitation. The invention is effective in abating both precious metal inclusions and non-metallic inclusions in the produced glass.

Abstract: A mold-press forming apparatus for applying a molding pressure to a mold containing a forming material to perform press forming includes a loading chamber (that is, an airtight chamber) P1 kept airtight. The loading chamber P1 is connected to a pressure reducing member which includes evacuating members 14 and 13 arranged in an evacuating path 7 connected to the loading chamber P1 for evacuating a gas in the loading chamber P1, and a plurality of valves 11 and 12 arranged in the evacuating path 7 in parallel to each other. When the loading chamber P1 is evacuated, the pressure reducing member changes a pressure reducing rate in the course of pressure reduction.

Abstract: A combustion method for melting glass in which two fuels of the same nature or different natures are fed into a fusion furnace at two locations remote from each other for distributing the fuel to reduce NOx emissions. The combustion air is supplied at only one of the locations. In a method for operating a glass melting furnace, the fuel injection is distributed to reduce NOx emissions. The furnace includes a melting vessel for receiving the glass to be melted and containing a bath of molten glass, walls defining the furnace, a hot combustion air inlet, a hot smoke outlet, at least one burner for injecting a first fuel, and at least one injector for injecting a second fuel. The injector has an adjustable flow complementary relative to the flow to the burner so that up to 100% of the totality of the first and second fuels used may be injected.

Abstract: A porous preform production apparatus having a reaction vessel which includes an upper deposition chamber having an air supply inlet and an exhaust outlet, a lower deposition chamber having an air supply inlet, and a top chamber disposed on top of the upper deposition chamber and adapted to lift and store a porous preform formed by deposition, characterized in that the floor of the upper deposition chamber is disposed at a height between the lower end of a straight body part and the deposition tip of the porous glass preform during deposition, and a connection opening which connects the upper deposition chamber with the lower deposition chamber, is provided on the floor of the upper deposition chamber, and that when the aperture diameter of the connection opening is designated as A and the diameter of the porous preform passing through the connection opening as B, the ratio B/A satisfies the expression 0.05?B/A?0.6.