Abstract: A lid construction for a heating vessel. Discrete insulating members are supported by water cooled pipes above the vessel. The cooling pipes fit into grooves along the vertical side walls of the insulating members. Each member has a support independent from the supports for the other members so that an individual member can be removed within having to remove additional members.

Abstract: A glass melting furnace including a melting tank heated from above by burners and comprising a melting section as well as a refining and homogenizing section provided with electrodes for the supply of electrical energy; a dam which separates the melting section from the refining and homogenizing section and the upper edge of which is disposed below the surface of the (glass) melt bath; and an outlet for the glass disposed in the bottom portion of the refining and homogenizing section; wherein the bottom of the refining and homogenizing section is in a position deeper than the bottom of the melting section, and the electrodes are arranged in one or more planes (levels) of the refining section, the glass melting furnace being configured such that on the side of the refining section there is provided adjacent to the dam a bottom portion which is disposed at a level substantially above the bottom of the homogenizing section.

Abstract: A forehearth for molten glass having at least one cooling zone which includes a trough and a roof over the trough. A pair of spaced projections extending downwardly from the roof to define a central channel over the molten glass and side channels over the respective side portions of the molten glass. The roof has an area of reduced thickness in the portion over the central channel. An enclosed upper cooling channel extends longitudinally over the area of reduced thickness and has an inlet and an outlet spaced from the inlet, and heating means are provided for each side portion of the forehearth.

Abstract: In a heating vessel wherein corrosive exhaust degrades exposed positions of the vessel, a high velocity gas jet injects gas between the corrosive exhaust and the exposed portions of the vessel. The gas minimizes contact between the exhaust and the exposed portions so as to reduce wear due to corrosive degradation.

Abstract: In a method and apparatus for liquefying material such as glass batch, primary thermal protection for the vessel is provided by a lining of the batch material, with secondary protection being provided by forced cooling of a minor portion of the vessel in regions and at times when the primary protection is irregular.

Abstract: Temperature conditioning of molten glass flowing from a melter to a glassware-forming machine is described. In addition to the attempt at conditioning the molten glass in the forehearth in the usual manner, in accordance with this invention, distribution channels leading from the throat of the molten glass supply to the forehearth are provided with conditioning apparatus. Most particularly, the conditioning apparatus is such that the conditioning temperatures at the opposite sides of the distribution channel may be varied. For example, at one side the interior of the distribution channel may be being heated while the opposite side is being cooled. It is also possible to heat one side to a greater degree than the other while heating both sides. Most particular, the burner construction is such that the burners may be utilized either to heat the interior of the distribution channel or to cool the same.

Abstract: A forehearth for a glass furnace includes a roof formed of a plurality of roof blocks designed to provide below the roof blocks a central longitudinal channel and side channels on each side of the central channel. An electric heating element is positioned in a bore in the roof blocks substantially directly above the side channels to permit radiation of heat to the glass surface above the side channels. The temperature of the molten glass utilizing the construction can be effectively uniformly controlled across its cross-section.

Abstract: Converting thermally meltable materials to a liquefied state is carried out on a lining of pulverulent material. As liquefied material is drained from the surface, additional unmelted material is fed onto the surface to maintain the lining substantially intact.

Abstract: A method of cooling molten glass, which comprises slowly cooling the molten glass while the average temperature of the molten glass is within a certain range extending below and above the temperature at which the speed of absorbing bubbles is highest, and cooling it rapidly when the average temperature of the molten glass is outside said range.

Abstract: A method of an apparatus for heat processing of glass and/or glass forming material wherein cullet and/or the raw materials needed to form glass are heated while suspended in a high temperature gas stream which may comprise products of combustion. The particles heated both in and downstream of a burner, for example, together with products of combustion are accelerated out of the burner, preferably downwardly, through a nozzle and against a closely spaced impact surface in a separation chamber. Upon impact, the particles and/or molten droplets are separated from the products of combustion by adhering to the impact surface and form a continuous flowing layer which flows from the impact surface, over a flow surface and as a molten layer into a pool of molten glass product at the bottom of the separation chamber.

Abstract: A temperature control system for a forehearth, said forehearth for thermally conditioning molten glass to be fed to a glassware forming machine, and being divided into a plurality of zones. Each of the forehearth zones is provided with devices for monitoring the temperature of molten glass within the zone, and apparatus for selectively heating the glass. A microprocessor-based time sharing system controls the temperature of the plurality of zones, using adaptive control loops. Each zone is assigned a time period for monitoring temperature and taking appropriate corrective action. Temperature adjustments may be made independently zone-by-zone, or in cooperation, and other physical parameters may be taken into account such as glass viscosity or combustion pressure. Certain time-sharing periods may be associated with monitoring and displaying functions only.

Abstract: A method of producing a glass product requiring minimum fining wherein finely pulverized glass batch material is heated very rapidly in suspension in a hot gas stream to at least about its melting temperature in a heating chamber and directing it through a nozzle to impact on an impact surface in a separation chamber where the glass batch material is separated from the hot gas stream by adhering to the impact surface.Upon impact, the particles and/or molten material form a continuously flowing layer which flows over a flow surface as a molten layer into a pool of molten glass product in a collection zone. The melt flow over the flow surface is controlled to effect the immigration of gas therein to and then leave the exposed surface of the melt flow and simultaneously effect at least substantial reaction of the glass batch material before it reaches the collection zone.

Abstract: A process and installation for heating a channel in which flows a mass of molten glass toward one or more forming machines. The channel includes a vault which carries at least one group of oxyfuel burners connected to a source of oxygen and to a source of fuel gas, these burners being so oriented as to produce curtains of flames directed towards the longitudinal marginal zones of the surface of the stream of molten glass.

Abstract: When primary fuel for combustion is combined with an amount of oxygen in excess of the stoichiometric amount required for complete combustion, in the ports of a glassmaking furnace, additional fuel is injected into the melting chamber to consume at least a portion of the excess oxygen and reduce at least a portion of NO.sub.x present in the melting chamber, to thereby reduce or suppress NO.sub.x emissions from the furnace.

Abstract: A method for manufacturing glass by melting a batch of raw material in a melting chamber of a continuous glass-melting tank furnace, permitting the glass to flow through a rising passageway and a sill provided by the furnace to a separate refining chamber in the furnace, the atmospheres in the melting and refining chambers being isolated, and heating the glass at the upstream end of the refining chamber to a higher temperature than that of the glass over the sill so that the glass leaving the sill plunges into the refining chamber and is precluded from forming a return current to the melting chamber.

Abstract: The glass melter has an outlet portion formed as a heating device for controlling the outlet flow rate of molten glass from the melter. Raw batch material that is used to form the molten glass is heated to a molten state at a first temperature range. The molten glass, while flowing toward the outlet of the melter, is cooled to a second temperature range to increase the viscosity of the molten glass to a desired level. The outlet member then heats the exiting molten glass a predetermined amount to decrease the glass viscosity in accordance with desired flow rate requirements. Heating of the outlet member is accomplished by imposing a relatively low voltage and a relatively high amperage on the outlet member. Accordingly, by using the outlet member as a heater a controlled flow rate of molten glass from the melter is achieved.

Abstract: In order to conserve fuel in an apparatus for manufacturing glass, a continuous glass-melting tank furnace is provided with a melting compartment, a refining compartment, and a shadow arch between the compartments. The shadow arch is constituted by a cover which extends from a shadow wall at the downstream end of the melting compartment to an end wall at the upstream end of the refining compartment. The melting and refining compartments communicate via a passage beneath the shadow wall at the downstream end of the melting compartment, and a sill is positioned between this shadow wall and the refining compartment. The top of this sill is at least as high as the top of the passage.

Abstract: Converting thermally meltable materials to a liquefied state is carried out on a support surface of the unmelted material. As liquefied material is drained from the surface, additional unmelted material is fed onto the surface to maintain a substantially constant layer of the unmelted material.

Abstract: A forehearth for the conveyance of molten glass has at least one cooling zone which includes a trough and a roof over the trough. A pair of spaced projections extend downwardly from the roof to define in the space below the roof a central channel over the central portion of the stream of molten glass and side channels over respective side portions of the stream of glass. The roof has at least one area of reduced thickness in the portion over the central channel. An enclosed upper cooling channel extends longitudinally of the forehearth over the area of reduced thickness and has an inlet and an outlet spaced longitudinally from the inlet. Heating means are provided for applying heat to each side portion of the stream of glass.

Abstract: Converting thermally meltable materials to a liquefied state is carried out by a plasma heat source encircled by a layer of the unmelted material. As liquefied material is drained from the surface, additional unmelted material is fed onto the surface to maintain a substantially constant layer of the unmelted material, thereby maintaining the temperature of the melting vessel relatively low and eliminating the need for forced cooling of the vessel.

Abstract: Molten material is heated by submerged combustion of hydrogen with oxygen so that the product of combustion injected into the melt is low in volume and consists essentially of water vapor which is relatively soluble in a material such as molten glass. Preferred embodiments involve liquefying the batch materials in a first stage and subjecting the liquefied materials to submerged combustion in a second stage.

Abstract: In a two stage glass batch liquefying process, calcium source material is preheated in a first stage in the absence of the major sodium source material, and the heated calcium source material and the sodium source material are combined and liquefied in a second stage.

Abstract: Apparatus for improving oxygen burner performance in a glass furnace having a chamber with a bottom wall connected to a roof wall by side walls, said walls having refractory surfaces, and an opening in the roof wall, comprises a burner for injecting a flame downwardly into the chamber through the roof opening with the flame being adapted to impinge against a bath of molten glass on the bottom wall of the chamber, a hopper for inserting a shower of cullet into the chamber through the roof opening, and a burner spout having a flared end for forming the shower of cullet into a shroud around the flame and for heating the shower of cullet and for forming the cullet into an annular ridge of unmelted cullet on the top surface of the molten glass bath, whereby said ridge deflects the flame upwardly when the flame bounces from the bath of molten glass so that the flame does not bounce horizontally and impinge against the near surface of the side walls, and the shower of cullet shrouds the flame and protects the furnac

Abstract: Glass batch materials and the like are liquefied in a first stage and the liquefied materials are subjected to submerged combustion in a second stage.

Abstract: According to the process, a mixture of powdered mineral substances is introduced at one end of a furnace and this mixture is heated, and the molten glass thus obtained is continuously discharged at the other end of the furnace. The mixture is heated by means of at least one air-fuel flame and at least one oxygen-fuel flame. A current of auxiliary gas which is concentric to and surrounds the oxygen-fuel flame is injected into the furnace.

Abstract: A melting furnace is disclosed which heats by joule effect to supply molten material of uniform temperature at the floor of the melter. During formation of molten material, an essentially isothermal condition across a given horizontal plane of the body of molten material is established. Spaced apart opposed electrodes and controlled current flow establish these uniform temperatures and allow molten material to be formed directly from the melter without further processing.

Abstract: There is disclosed an apparatus and method of recovering a portion of the waste heat produced in a high temperature industrial process, such as a glass melting furnace, where the furnace has at least a pair of regenerators which are alternately used to preheat the combustion air and serve as hot exhaust heat storage means. The hot exhaust gases from the process are passed through a heat exchanger where the heat is indirectly transferred to the clean compressed air at 100 psi from the compressor of a Brayton cycle energy recovery system with the hot compressed air being expanded in a high performance turbine. The exhaust from the turbine will be at atmospheric pressure and at a temperature between 750.degree. F. and 900.degree. F. This turbine exhaust is fed to the opposite side regenerator as clean preheated combustion air.

Abstract: In a process for liquefying glass batch and the like, wherein a layer of batch is maintained as a lining in the liquefaction vessel, the thickness of the lining is monitored by measuring the temperature in a region facing an end portion of the lining. Preferably, a series of thermocouples serves to determine the location of the face of the lining on which liquefaction is taking place.

Abstract: Process control method and apparatus for an ablation liquefaction chamber including primary and secondary burners positioned to direct a primary combustion flame for electively heating portions of the chamber interior for control of product temperature and chamber pressure.

Abstract: Liquefying of pulverulent batch materials (e.g., glass batch) is carried out in two stages. The first stage utilizes extended gas/solid contact to heat the materials to an intermediate temperature, and may recover waste heat. The second stage rapidly liquefies the material in a cavity lined with the batch material, and may employ substantially nitrogen-free heat sources. Another aspect involves maintaining a wet condition in the first stage to entrap particulates.

Abstract: A conditioning section of a forehearth is disclosed with sidewall electrodes for Joule effect heating of glass positioned and connected to confine the current and Joule effect heating separately to the side portions of the molten glass flow path therein. Separate circuits, controls, temperature sensors and temperature set point control means are provided for the sidewall electrodes on each side. Glass temperature across the flow path is controlled and can be adjusted by separately controlling the flow of Joule effect current along each side of the flow path through manual or automatic, thermally actuated, controls for each side.

Abstract: Forehearths for use in glass production comprise a refractory trough (52) for molten glass with an insulating roof thereover, means for heating glass in the trough and means for blowing cooling air across the inside of the roof surface; the forehearth being constructed of at least two sections (A, B and C) which have different insulating characteristics from each other. Preferably the forehearth roof is made up of prefabricated block members of refractory material lying side by side and each of which member spans across the trough. Different insulation is provided over the prefabricated block members to provide different insulating characteristics within sections of the forehearth. The invention also provides prefabricated members for use in the construction of the forehearth according to the present invention.

Abstract: In an arrangement for liquefying pulverulent materials such as glass batch, the material to be liquefied is deposited onto a sloped surface comprised of a compatible pulverulent material retained in place by a grid-like member.

Abstract: The outside walls of the regenerator of a glass melting furnace is coated with a high temperature silicone elastomer. Several coats are applied in those areas of high differential pressure and low relative resistance to air flow therethrough. The cleanout panels in particular are provided with several coats.

Abstract: A conventional glass tank furnace used in the manufacture of glass is provided with a system for recovering heat which inevitably escapes from the furnace roof or crown above the melting and refining tanks of the furnace. A heat recovery plenum means is mounted on top of the furnace roof or crown, and an air blower supplies cool air to the plenum means through a first duct means. The cool air directed to the plenum means cools the furnace crown and in the case of a suspended flat arch crown, the supporting steel work. The cool air in the plenum means is heated by heat escaping from the furnace crown, and thereafter is directed through second duct means to a main combustion air blower where the heated air from the plenum means is mixed with primary combustion air and directed to the furnace and to the furnace burners. Control means are provided to maintain the air in the plenum means at positive pressure so as to prevent air in the furnace from escaping through the furnace crown.

Abstract: A method and apparatus for electrically melting solidified glass in difficult to reach regions of a glass melting furnace not readily accessible with fossil fuel heating means and, more particularly, to an electrode arrangement for electrically heating solidified glass in difficult to melt regions such as a submerged outlet throat between a furnace melter section and the riser through which the glass is supplied in production.

Abstract: A container between the output of a melting furnace wherein the molten mass is also refined, such as for glass, and the ducts to a plurality of forming machines comprising a larger first zone and a plurality of smaller second zones corresponding to each forming machine, in which container the molten mass is controlled in temperature above and below its liquid level as it flows through the first and second zone toward a forming machine so that the cross-sectional area of the molten mass at the outlet duct from each second zone has substantially a uniform temperature.

Abstract: An apparatus and method is disclosed for cooling a molten stream of glass flowing in a firebrick hearth from an entrance end to an exit end of a glass furnace forehearth, the method comprising the steps of: cooling the bottom of the hearth which cools the molten glass by forcing air through ducts in the hearth bottom insulation; cooling each side of the hearth which cools the molten glass by forcing air through ducts along the side of the hearth.

Abstract: A method for controlling a glass melting furnace comprises measuring the temperature T of the glass in the furnace, measuring the heat being supplied to the glass in the furnace, calculating the entropy E according to the equationE=(Q/T)comparing E with a predetermined entropy E.sub.O, changing Q to a new value of heat Q' responsive to (E-E.sub.O), and supplying heat Q' to the furnace.

Abstract: Molten glass entering from a refiner is conditioned, in an optimum operation, such that its temperature along the center of the flowing glass just in advance of its entry into the feeder, will be of equal temperature near the surface near the bottom and intermediate these two points. A tri-level thermocouple is positioned along the center line at approximately nine inches from the feeder for monitoring these temperatures, and to serve as an aid to the operator in controlling the actual glass temperature. Positioned at opposite sides of the forehearth, approximately eight inches from the center line, are tri-level thermocouples. The three couples will be positioned at the same relative depths as those at the center line. The center thermocouple on the right side will have its output used as the control temperature for a temperature override circuit connected to the electrodes.

Abstract: The initial step of melting glass, converting particulate batch materials to a partially melted, liquefied state, is carried out on a support surface of batch. As liquefied batch is drained from the surface, additional batch is fed onto the surface to maintain the surface substantially constant.

Abstract: A skimmer for use in a throat of a melting furnace. The skimmer comprises a plate having a plurality of passages therein with the passages being through the plate from a first side to a second side. Adjacent passages are in communication with each other to form a continuous passage through the plate. A first means for blocking the ends of the passages on the first side of the plate and a second means for blocking the ends of the passages on the second side of the plate are attached to the plate. A first port means is in communication with one end of the continuous passage for connecting with a cooling inlet located outside of the furnace, and a second port means is in communication with the other end of the continuous passage for connecting with a cooling outlet located outside of the furnace.

Abstract: A combination comprising a recuperator, a crown vent and a furnace having a crown vent opening is supplied, the crown vent extending upwardly into the recuperator and downwardly beneath the wall of the crown vent opening.

Abstract: Method and device for reducing NO.sub.x content in the waste gas generated in a glass melting furnace of side firing or end firing type equipped with a heat recovering device, comprising supplying hydrocarbons in a counter flow to that of the waste gas by combustion, or from the corners of the combustion chamber into the combustion chamber over the melt tank.

Abstract: NO.sub.x emissions from a glass melting furnace are reduced by injecting ammonia into the exhaust gas stream on a flue between primary and secondary regenerator chambers in one embodiment, and in staged zones within a regenerator in another embodiment.

Abstract: A continuous tank-type glass melting furnace containing a bath of molten glass and having a waist section of reduced width whereat a submerged weir extends across the path of the molten glass bath flowing therethrough. The weir is located adjacent the floor of the waist section for modifying the flow path in the lower regions of the molten bath between the refining and conditioning zones of the furnace. Also, a surface barrier and stirrers may be provided in the waist section for improving the homogeneity of the molten bath.

Abstract: An electrically heated and/or gas heated forehearth channel has a heat conductive refractory roof structure with arch blocks supported from the sides of the channel on side blocks, some of which side blocks may include gas burners for achieving rapid initial heating of the glass contained in the channel. Once the glass temperature has been raised close to normal operating temperature electrodes heat the glass by Joule effect electrical resistance heating, and the gas burners are no longer required. A roof superstructure is provided of insulating brick, and defines muffled cooling passageways such that the gas or electrically heated forehearth can be effectively operated by removing heat from the top of the conductive refractory arch block roof structure. Means is provided for selectively cooling the underside of these arch blocks when the gas burners are operated, or directing the flow of cooling air through the muffled cooling passageways in the roof superstructure when electric heat is employed.

Abstract: A glassmaking tank furnace which comprises a basin, a heating system, a housing which includes a roof and a gas flue, a cooling system, a feed port and a discharging port. The bottom and walls of the basin and at least a part of the housing formed with the feed port are defined by fittingly adjoining metal tubes of the cooling system, which ensure a continuous operation and long service life of the furnace and set up favorable conditions for further intensification of the melting process.

Abstract: In a regenerative furnace of the type used for melting glass, localized overheating of the regenerating regenerator packing is minimized and heating of the regenerator packing is made more uniform by the utilization of a manifold flue. The gas distribution space is in continuous contact with the regenerator packing while the manifold flue is joined to said gas distribution space at a plurality of points below the regenerative packing. Further, flow control dampers may be located in the flue between the regenerative packing and the joining point of the manifold flue and another damper may be in the manifold flue itself to regulate the passage of gas to and from the regenerative packing so that the packing is evenly heated or cooled.

Abstract: The initial step of melting glass, converting particulate batch materials to a partially melted, liquefied state, is carried out on a support surface of batch. As liquefied batch is drained from the surface, additional batch is fed onto the surface to maintain the surface substantially constant.The questions raised in reexamination request No. 90/000,701, filed Dec. 31, 1984 have been considered and the results thereof are reflected in this reissue patent which constitutes the reexamination certificate required by 35 U.S.C. 307 as provided in 37 CFR 1.570(e).