Abstract: The invention relates to a process for continuously producing a glassy or vitrified blast furnace slag, in which the slag is applied onto a cooling roll or onto articulately interlinked cooling plates conducted as an endless conveyor belt over deflection pulleys and wherein cooling of the slag is effected dry, wherein the liquid slag is supplied to an intermediate storage and from that intermediate storage is continuously applied onto the cooling plate belt, or cooling roll, via a distributing channel in parallel strands at temperatures of above 1350° C., whereupon the cooled slag is thrown off and comminuted or granulated dry in a crusher. The invention, furthermore, relates to an arrangement for carrying out the process.

Abstract: A process of producing granules of a reactive metal. The process comprises providing a source of molten reactive metal (41), forming discrete droplets (53) of the molten metal, contacting the droplets while still substantially molten with a fluidized bed of particles (12) maintained at a temperature substantially below the solidus temperature of the metal and freezing the droplets as discrete granules of the reactive metal in the fluidized bed. The invention also provides apparatus for carrying out the method and product produces by the method, including a magnesium-containing additive for aluminum alloying. The use of a fluidized bed for cooling and freezing the droplets avoids problems encountered in prior methods and also makes it possible to provide coatings of various kinds on the surfaces of the granules, if desired.

Abstract: A process for recycling trash and obtaining a glassy vitreous product by mixing trash with a vitrifying composition comprising 30% Sodium Sulphate, 7% Quartz, 20% Calcium Carbonate, 23% Sodium Carbonate, 13% Organic Sulphate (consisting of 20% Sodium Sulphate and 80% Carbon Hydrates) and 7% Calcium Fluor, the composition comprising the 10-20 weight percentage of the mixture and thermochemically transforming the mixture, the product being used in multiple applications. The glassy product obtained by the process is also provided by the invention.

Abstract: An improved method for modifying slag in an electric arc furnace comprising introducing into the slag, or on top of the slag, vermiculite platelets which have been refined into concentrated form whereby the flakes comprise at least 50%, and more preferably at least 80%, by dry weight hydrated magnesium aluminum (iron) silicate.

Abstract: A method of processing material for use in production of rock wool, comprises providing the material in finely divided form; mixing the finely divided material with a fibrous binding agent; and forming the mixture into solid blocks. The resulting blocks (lacking fines) are in a form suitable for use in the production of rock wool, and may be fed to a smelting furnace, together with other ingredients as appropriate, for processing in conventional manner. In one preferred embodiment, the material is waste rock wool, such as spent hydroponic growth medium or shot. By use of the invention, shot which has hitherto constituted a waste material can be recycled and reused in the production of rock wool, thus obviating the waste disposal problem and improving the overall efficiency of the rock wool production process. The invention also covers the resulting solid blocks and a method of producing rock wool using the blocks.

Abstract: A process for making mineral wool fibers having high-temperature stability consisting essentially of: (a) preparing a mixture containing basalt and a quantity of uncalcined raw bauxite sufficient to provide the resulting fibers with an alumina content of at least 18 weight percent, preferably of from 19 to 23 weight percent; (b) heating the mixture to a temperature sufficient to form a substantially homogeneous melt, e.g., in a cupola furnace using coke in a quantity of from about 11 to 25 percent by weight of the mixture; and (c) forming the melt into fibers. The mixture may optionally contain a flux, e.g., limestone and/or dolomite, such as a flux providing a weight ratio of limestone plus dolomite to basalt of less than about 0.6, e.g., 0.1-0.4. The mixture may also contain slag in a weight ratio of slag:basalt of less than about 1.0, more preferably about 0.6.

Abstract: An environmentally safe abrasive composition which contains at least about 60 weight percent of ferrometalsilicate, at least about 5 weight percent of spinel, and at least about 70 weight percent of crystalline material. This composition has a Vickers hardness of at least about 550 and a density of from about 2.8 to about 4.1 grams per cubic centimeter. It is crystallized in situ from a thermally crystallizable mixture comprising from about 50 to about 75 weight percent of electric arc furnace dust, from about 5 to about 40 weight percent of glass, and at least about 10 weight percent of silica sand.

Abstract: The present invention provides a method for treating rotary slag containing iron and sodium compounds. The method involves treating the slag in a sulfuric acid solution to convert the iron and sodium within the slag to iron sulfate and sodium sulfate. The iron sulfate (along with substantially all of the heavy metal contaminants) forms a precipitate, while the sodium sulfate remains in solution. The precipitate can then be separated from the solution.

Abstract: A method for aging steel-making slag comprising the steps of charging normal temperature steel-making slag crushed to the extent that the slag having a grain diameter of 25 mm or less which constitutes 80% or more of the total amount into a pressure vessel which can be closed tight enough to seal a pressure substantially higher than atmosphere. The pressure vessel is closed and pressureized steam is supplied into the said vessel for heating the said pressure vessel and slag to raise the temperature and the pressure in the said pressure vessel while discharging condensed hot water. The interior of the vessel is kept under a condition saturated by steam and pressurized up to 2 to 10 kg/cm.sup.2 G for 1 to 5 hours. The pressure in the pressure vessel is reduced to be equalized with atmosphere. The steel-making slag is then discharged from the vessel. Apparatus is provided for carrying out the above process and includes a pressure vessel having an opening lid for charging and discharging steel-making slag.

Abstract: The present invention concerns a method for melting recycled silicate starting materials. A rotating transport flow with helical flow filaments of transport air and starting material is supplied in the direction of the helix axis into the combustion chamber of a cyclone furnace. Preferably, pre-heated fresh air is used which is supplied partly into the combustion chamber as combustion air therefor and partly in the form of the transport air. Furthermore, the present invention concerns a device for melting recycled silicate starting materials. The device includes a combustion chamber where fuel and combustion air can be burnt up in the presence of the starting material. A forechamber is arranged between an admixer for generating an injector flow and the combustion chamber. The injector flow can be supplied into the forechamber through a charging conduit to generate a transport flow made up of starting material and transport air. The forechamber includes an outlet port opening into the combustion chamber.

Abstract: Molten matte or slag is water granulated by feeding molten matte or slag through a launder to a granulator tank. The tank includes sloping walls and is equipped with adjustable overflow weirs and one or more of spray nozzles. These nozzles are positioned such that the water that they emit impacts on substantially all of the molten matte or slag that is fed to the granulator tank. The granulation tank is optionally coated with a polymeric material to reduce the potential for phreatic explosions. The granulator is also optionally equipped with a gas offtake which can be connected directly to a quench tower which in turn can be connected to an induced ventilation system.

Abstract: A process for making an abrasive composition. In the first step of this process, from about 50 to about 85 weight percent electric arc furnace dust is mixed with at least about 10 weight percent of silica to prepare a thermally crystallizable mixture; the electric arc furnace dust has a particle size distribution such that at least about 70 weight percent of its particles are smaller than about 20 microns, and it contains from about 35 to about 65 weight percent of at least an iron material selected from iron, iron oxide, and mixtures thereof. Thereafter the mixture is melted by subjecting it to a temperature of from about 2,300 to about 2,900 degrees Fahrenheit to form a glass melt, the glass melt is quenched by reducing its temperature at least 1,000 degrees Fahrenheit in less than about 5 seconds to form a quenched glass, and the quenched glass is crushed by subjecting it to a pressure of at least 1.0 MegaPascal.

Abstract: Metallurgical slag is expanded to produce a lightweight solid by forming a stream of molten liquid slag of controlled rate of flow and mixing the stream of slag with a controlled quantity of water and flowing the interacting mixture of slag and water into a receptacle. The interaction between slag and water is allowed to proceed for a predetermined period of time to form an expanded solid without the addition of any additional cooling water which would otherwise quench the material and vitrify it. In the receptacle, a vaned rotor operates to segment the interacting mixture of slag and water and project the segmented mixture through the air for collection into a heap.

Abstract: A method of producing a resilient decorative construction material from waste products such as slag granulate or waste glass granulate is taught. The waste glass granulate may contain paper, adhesives, plastic, or other contaminants. The construction material may be in the shape of a tile and used in interior or exterior applications. A layer of material comprising glass granulate, slag granulate, or sand, or mixtures thereof, is placed in a heat-resistant mold. The layer has first and second surfaces. The layer is thermally treated, and is initially heated so that a temperature gradient is established throughout the layer, with the first surface having a first temperature no greater than the softening point, and the second surface having a second temperature less than the first temperature. These temperatures are held for a period of time, and the layer subjected to further heating.

Abstract: Processes and systems for producing cementitious materials from ferrous blast furnace slags. Processes comprise mixing of a source of CaO with molten slag flowing from at least one slag tap hole of a blast furnace. Sufficient CaO is mixed with the molten slag to raise the ratio of CaO to SiO.sub.2, the C/S Ratio, of the slag to between about 1.06 and 1.25, while maintaining the Base Number of the molten slag less than about 1.55. The slag is then water granulated and ground to a predetermined degree of fineness. An activator then is added to the ground granulated slag. The C/S Ratio of the granulated slag determines the degree of fineness to which the granulated slag must be ground to achieve a desired hydration rate in the resultant cementitious material. Cementitious materials with C/S Ratios in this range may be ground less finely, yet possess the same hydration rates, as other more finely ground cementitious materials.

Abstract: A granulator comprises a rotary atomizer on to which the molten material to be granulated is poured in a stream. The rotation of the atomizer causes the molten material to be ejected therefrom in the form of globules. No fluid jets are used to break up the molten material. The globules pass through an enclosure and partially freeze to form granules which are collected in an annular trough. A gas is injected into the trough to induce a circumferential movement of the granules within the trough towards at least one exit from the trough.

Abstract: This invention provides a process wherein hazardous or radioactive wastes in the form of liquids, slurries, or finely divided solids are mixed with finely divided glassformers (silica, alumina, soda, etc.) and injected directly into the plume of a non-transferred arc plasma torch. The extremely high temperatures and heat transfer rates makes it possible to convert the waste-glassformer mixture into a fully vitrified molten glass product in a matter of milliseconds. The molten product may then be collected in a crucible for casting into final wasteform geometry, quenching in water, or further holding time to improve homogeneity and eliminate bubbles.

Abstract: Processes and systems for producing cementitious materials from ferrous blast furnace slags. Processes comprise mixing of a source of CaO with molten slag flowing from at least one slag tap hole of a blast furnace. Sufficient CaO is mixed with the molten slag to raise the ratio of CaO to SiO.sub.2, the C/S Ratio, of the slag to between about 1.06 and 1.25, while maintaining the Base Number of the molten slag less than about 1.55. The slag is then water granulated and ground to a predetermined degree of fineness. An activator then is added to the ground granulated slag. The C/S Ratio of the granulated slag determines the degree of fineness to which the granulated slag must be ground to achieve a desired hydration rate in the resultant cementitious material. Cementitious materials with C/S Ratios in this range may be ground less finely, yet possess the same hydration rates, as other more finely ground cementitious materials.

Abstract: A thermally stable steelmaking slag is produced which is suitable for use in applications requiring dimensional stability, e.g. as aggregate in road construction. Fine particles of slag obtained from a basic oxygen furnace operation or from an arc furnace operation is firstly subjected to a thermal hydration at a temperature in the range of about 100.degree. to 400.degree. C. Thereafter, the hydrated slag particles are carbonated in the presence of carbon dioxide at a temperature in the range of about 500.degree. to 900.degree. C., whereby substantially all free calcium oxide in the slag particles is converted to calcium carbonate. The product obtained is well suited for road construction and cementitious applications.

Abstract: The present invention relates to a process for forming glass-ceramic tiles. Spent aluminum potliner containing carbonaceous material, fluorine, and glass forming materials is oxidized under conditions effective to combust the carbonaceous material and volatilize partially the fluorine in the glass forming materials. The oxidized glass forming materials are vitrified to form a glass melt. This glass melt is then formed into tiles containing fluorine.

Abstract: The present invention relates to a process for the production of metal alloys, metal oxides and slag-based products, such as mineral wool, from industrial waste materials. More specifically, the present invention relates to a process for recycling industrial waste materials into valuable commercial products, including, pure metals, metal alloys, metal oxides, and a molten slag comprising non-reducible metal oxides which thereafter can be converted to vitreous fiber and shot. Industrial waste materials suitable for use in the present invention include metal-containing waste products, particularly inorganic hazardous waste materials. The present process accomplishes total recycling in such a manner that the entire industrial waste material is consumed and converted to useful products.

Abstract: The invention concerns a raw material briquette for mineral wool production containing a mineral raw material as well as a binder therefor. The invention is characterized in that the briquette, as the binder, contains slag which has been activated with an alkaline agent, such as with an alkalimetal compound. The invention also concerns a process for the preparation of the briquette as well as a process for the preparation of mineral fibres using the briquette according to the invention.

Abstract: A method is disclosed for water-granulating calcium ferrite slag which is produced in copper converting processing and contains 10 to 30 weight % of CaO. In the method, water is caused to flow at a flow velocity of 7 to 25 m/sec, and the calcium ferrite slag is introduced into the water flow such that weight ratio of water to slag amounts to no less than 100. With this method, the occurrence of phreatic explosions can be effectively avoided.

Abstract: The initial stages in the manufacture of a glass-like mineral fiber suitable for a multiplicity of industrial uses are essentially conventional; a charge of raw minerals (igneous rock, basalt, slag from a blast furnace or other metal working furnace, phosphate slag, etc.) is melted, then spun and collected to produce a fibrous mineral "blanket". The "blanket" is chopped up, separated, and screened, producing a prilled material constituting a multiplicity of mineral fiber pellets of given average size. These pellets are subjected to brief, rapid acceleration, as by contact with a high-speed toothed rotary wheel, to accelerate and stress the pellets into an industrially usable material constituting a multiplicity of shredded, flake-like mineral fiber elements, at least one such element for each pellet.

Abstract: For obtaining mineral fibers from a thermoplastic material having a high melting point, and more precisely for the regulation of the flow rate and temperature of the stream of molten material distributed on the fiber-drawing machine, the molten material is conveyed via a reservoir where the flow rate is regulated and the height of the molten material at the base of the tapping aperture is controlled by inclining the reservoir. Preferably the molten material is subject to a basic heating process which raises its temperature close to the fiber-drawing temperature and, in the vicinity of the tapping aperture, it is subject to additional heating in order to adjust the temperature precisely.

Abstract: A method of destructing mineral-wool scrap and reusing the scrap in the manufacture of mineral wool includes introducing the mineral-wool scrap in a finally divided state into a container causing the finely-divided mineral-wool scrap to pass through a heating zone generated by an oxygen burner such as to convert the mineral-wool scrap to a liquid state and delivering the molten mineral-wool scrap into a furnace in which a melt for manufacturing mineral-wool is produced or to an intermediate container mounted between the furnace and a spinning machine. When the molten mineral-wool scrap is being delivered to the intermediate container, molten material taken from the furnace is also delivered to the intermediate container.

Abstract: A method for processing hot, liquid slag includes the steps of: conveying the slag to be processed to an upper region of a granular material forming a fluidized bed that has a temperature below the solidification temperature of the slag; cooling the slag to a temperature below its solidification temperature while simultaneously forming granules; and maintaining the temperature of the fluidized bed at a temperature below the solidification temperature of the slag.

Abstract: Waste is incinerated in a rotary furnace which discharges slag and exhaust gas connected to an afterburning chamber. The slag is discharged from the afterburning chamber directly into a glass melting furnace while the exhaust gas is removed to scrubbers which remove residues which are then fed to the glass melting furnace. Cullet and other glass forming materials are also added to the furnace in order to form a vitrified product.

Abstract: The present invention provides a new process and a new apparatus for the treatment of steel-mill slag in a vessel which allows a wet granulation of the slag without the risk of explosions. The slag is caused to flow through a taphole at the bottom of the vessel, and the flow rate of the slag is determined by means of a continuous check of the weight of the vessel. One or more jets of granulating water, the flow rate of which is adjusted as a function of the slag flow rate, are directed onto the stream of slag flowing from the vessel. The apparatus comprises a vessel containing molten slag. This vessel is equipped with weighing means, with a taphole, with a device for shutting off the taphole, with means for maneuvering the shut-off device between an operating position and a stored or parked position away from the taphole and with a device for opening or freeing the taphole, engageable through the latter in order to initiate the flow of slag.

Abstract: A method for processing ash residues and other solide combustion products, derived from combustion of waste materials in furnaces whereby the ash and other combustion products are gradually supplied in a continuous manner into the high side of a glaze-kiln, showing a sloping course, which is heated from its lower side, and are fused and glazed in a continuously proceeding process at high temperatures and a glaze-kiln, useful in this method.

Abstract: A method and device for the economic and environmentally safe disposal of waste material and molten slag from a cupola furnace comprises admixing the waste material with either molten slag or granulated slag so as to form a homogeneous mixture of the waste material in the slag material and thereafter feeding the mixture to a collection container.

Abstract: The invention provides a new enclosure for slag pelletizers, and a new method of operating such an enclosure, that minimizes the noise and the escape into the ambient atmosphere of hydrogen sulfide and airborne particulate material produced by the pelletization. The enclosure consists of impereable walls and a roof, the pelletized material being removed through an openable door at one end that is closed during the process. The enclosure has three successive zones, in the first of which contains the pelletizer, this being supplied with only the amount of water needed for pelletization. In the second zone containing the slag pile a plurality of very fine mist producing nozzles supply water to the gases to cool them using its latent heat of evaporation, the amount of water supplied being such as to cool them as much as possible while being limited so that it all remains vaporized and cannot enter the slag pile to increase its moisture content.

Abstract: A process for producing mineral fibers and the fibers thus produced are disclosed. The process involves forming a melt comprising an alumina-containing residue from a metal melting operation and one or more mineral raw materials suitable for forming mineral fibers, dividing the melt into streams and cooling the streams to produce the fibers. The residue from the metal melting operation acts as an inexpensive, substantially non-polluting source of alumina which can be used to increase the alumina content of the fibers and thus improve their properties, or which can be used as a replacement for more expensive or less desirable sources of alumina.

Abstract: An enclosure for slag pelletizers, and a method of operating such an enclosure, that minimizes the escape into the ambient atmosphere of airborne fibres produced by the pelletization process, while permitting the necessary free passage of the steam and gases that are also produced. The enclosure roof consists of at least one layer of wire mesh and a system of overlapping baffles is provided beneath the roof at least above the pelletizer to intercept the particulate material, so that the pellets do not disrupt a blanket of the fibre which is allowed to accumulate on the wire mesh to facilitate removal of the remainder of the fibre from the air stream. The method allows the deposition of an effective blanket, while preventing the deposition of too much fibre, so that the gas stream is diverted and flows out of the open end of the enclosure.

Abstract: A method and means for producing mineral wool from coal slag is described wherein molten coal slag is transferred from a coal slag tank in an electrical generation plant. The molten coal slag is transferred to a fiberization apparatus and is heated during the transfer process to maintain the coal slag in a molten state. In the fiberization apparatus, the molten coal slag is subjected to compressed air streams which creates mineral wool fibers which are collected in a collection apparatus.

Abstract: An apparatus and method are disclosed for processing glass-making materials under oxidizing conditions, and for processing materials, such as hazardous or toxic wastes, or smelting under reducing conditions. As a glass-making apparatus the invention includes a cyclone melt reactor for forming a liquid glass melt and a combustion preheater for receiving the glass-making materials and combusting the fuel and oxidant therein to heat the glass batch materials to a temperature at least equal to the melt temperature of the glass batch material. The combustion preheater has an outlet connected to the glass melt reactor, and at least one inlet is provided into the combustion preheater for introducing oxidizing materials and for creating a well-stirred region within the combustion preheater means.

Abstract: A process and apparatus for granulating slag in which molten slag is charged into a drum and is solidified and granulated therein on cooled surfaces. To ensure a rapid cooling at a high thruput rate, the molten slag is applied to the inside surface of a drum, which rotates on a horizontal axis and has a cooled shell, and the solidified film of slag is mechanically detached from the inside surface after about three-quarters of a revolution of the drum and is discharged.

Abstract: A steel slag or iron slag which is a by-product generated at the time of steel or iron metallurgy and a method of manufacturing the same are disclosed. This slag is characterized in that it contains at least 0.15 wt % of boron component in the form of B.sub.2 O.sub.3 and has resistance against degradation in the fused slag cooling-down process and against generation of yellowish turbid water at the time of contact of slag with rain water.

Abstract: The operation of mineral wool cupolas is improved in several respects and a waste material is efficiently disposed of by using spent pot lining from electrolytic aluminum reduction vessels in the mineral wool cupolas as a partial or complete replacement for coke. The spent pot lining is impregnated with a cryolytic type slag material which aids in both reducing the reactivity of an already unreactive graphitic material such that it burns low in the cupola with desirable thermal results and also prevents the formation of siliceous build-up in the cupola hearth areas. Several variations of cryolytic impregnated carbonaceous materials having the desirable effect of the invention are possible and described.

Abstract: An improved charging process for an enclosure for melting materials such as blast furnace slags or basaltic glasses. The supply of combustive gas is carried out nonuniformly in order to create a gas circulation velocity gradient in the section of the cupola corresponding to the level of the tap hole, with the lowest circulation velocities meeting in the vicinity of the tap hole.

Abstract: Method of preparing a melt for the production of mineral wool wherein suitably composed raw material and coke are fed into a preheating zone in the upper portion of a shaft furnace and are caused to descend down through the oxidation zone in which air is introduced to effect a combustion of the coke and to heat the raw material to a temperature not exceeding 1000.degree. C., and wherein the actual melting is effected by plasma heating in the lower portion of the shaft furnace where which the melt formed is discharged.

Abstract: In order to reduce or avoid the discharge of gaseous pollutants H.sub.2 S and SO.sub.2 to the environment in a process for the production of slag sand (granules) from blast-furnace slag by granulation of the slag by means of a water jet, the propulsion jet interspersed with water vapor, granules and pollutants is injected directly into a water receiver, the residual vapor still remaining and the pollutants H.sub.2 S and SO.sub.2 not yet washed out are cooled down in a condenser in counter-current with spray water and condensed, and the residual gas remaining after the vapor condensation is taken off from the top end of the condenser and recycled via a recycle line back to the injector.

Abstract: A process for making a homogeneous melt for producing mineral wool insulation. This insulating material is made from waste products namely, bottom ash, cement kiln dust, slag, and waste from mineral wool production. These materials, along with a binder, are homogenized into a mixture. Thereafter, the process includes briquetting the mixture into agglomerated pieces. The agglomerates are then melted in a cupola furnace and the molten agglomerate is discharged into a receiver. Hot combustion gases are then passed into the melt or molten agglomerate to chemically homogenize the melt and heat the melt to preselected temperature. Thereafter, the melt is converted into fibers using conventional practices.

Abstract: An apparatus for preventing the solidification and accumulation of material from the tapping jet in and on the tapping spout in the manufacture of mineral wool includes at least one oxy-fuel burner at the discharge section of the tapping spout to the spinning machine. The burner (13) is disposed at such a distance and directed such that the discharge section of the tapping spout and the first portion of the tapping jet departing from the spout are heated by the burner flame and the impulse of the burner flame is of such a size that the configuration and position of the jet will remain unaffected.

Abstract: To produce basalt wool having a large fibre diameter of if desired 10 .mu.m with high output and low bead formation, the exit cross-section of the exit orifices (6) of the distributor tank (5), the vertical distance (vA) between the exit orifices (6) and the blow-in slits (29) for propellant gas, the horizontal width (hB) of the nozzle slot (10) and the vertical length (vL) of the nozzle slot (10) downstream of the blow-in slits (29) are dimensioned to be unusually large for an apparatus for producing rock fibres by blast drawing. As a result, it is possible to operate at a low melt temperature and a high propellant gas rate combined with a low propellant gas pressure in order, surprisingly, to obtain a coarse-fibered product with low bead formation and high output.

Abstract: A valve apparatus for the precise regulation of a stream of molten material such as molten rock or slag as it issues from a primary melter or holding device, comprising a frame retaining a valve, the valve comprising a pair of plate-form valve members, one fixed and one movable with respect to the other, each having an aperture or orifice provided therein. Maximum rate of discharge occurs when the apertures are in juxtaposition, and flow cut-off occurs when the apertures are not in juxtaposition. Power operated means is provided for the movable valve member to obtain proper stream regulation or complete cut-off. The apertures are so contoured that, as the valve is moved toward closed position, the cross-sectional shape of the effective opening and the flowing stream of molten material remains substantially uniform and unchanged.

Abstract: An apparatus for air-pulverizing high-temperature molten slag by blowing air at high speed through a nozzle into a flow of molten slag that is falling from an inclined container by the intermediary of a turndish. A heat detector is provided for detecting the quantity of heat in the flow of molten slag after being air-pulverized by the high speed air flow, and a feedback control device which is responsive to a detection signal issued from the detector is provided for calculating a desirable inclination angle of the container or the turndish and transmitting a control signal obtained as a result of the calculation to a controller for controlling the inclination of the container or turndish thereby stabilizing the air-pulverizing of the high-temperature molten slag.

Abstract: A valve apparatus for the precise regulation of a stream of molten material such as molten rock or slag as it issues from a primary melter or holding device, comprising a frame retaining a valve, the valve comprising a pair of plate-form valve members, one fixed and one movable with respect to the other, each having an aperture or orifice provided therein. Maximum rate of discharge occurs when the apertures are in juxtaposition, and flow cut-off occurs when the apertures are not in juxtaposition. Power operated means is provided for the movable valve member to obtain proper stream regulation or complete cut-off. Each valve member is formed of a plate of metal having an internal channel through which water is circulated to reduce the temperature of the valve member and to prevent its destruction by overheating.

Abstract: A process is provided for treating an aqueous stream of nonradioactive hazardous waste containing inorganic compounds capable of forming oxides upon thermal treatment in which at least one of the oxides is a glass former, glass intermediate or a glass modifier. The process comprises (a) introducing the waste stream into a thermal treatment zone; (b) heating the inorganic compounds in the thermal treatment zone to convert the compounds to the corresponding inorganic oxides and form a melt solution while vaporizing volatile components to form an off-gas; (c) scrubbing the off-gas to provide a ventable flue gas and a liquid condensate with the condensate being recycled to the thermal treatment zone; and (d) removing the melt solution from said thermal treatment zone and cooling the melt solution to form a nonleachable glass containing the hazardous waste. An apparatus particularly adapted to practice the process is also provided.

Abstract: The invention relates to the production of mineral fibers from a material melted in a cupola. To regularize the supply of material to the fiber-forming apparatus, the material emanating from the cupola and conveyed to the apparatus passes through a reserve.