Abstract: Silica is reacted with sodium carbonate to form sodium silicate as a preliminary step in a glass melting process. Preferably, calcium carbonate-containing batch materials are calcined separately and then combined with the sodium silicate as liquefying is initiated. The materials may be substantially free of bubble-producing carbonates as the molten phase begins to form.

Abstract: A method of converting fine particle size alkaline earth metal carbonate, e.g., barium or strontium carbonate, into a free-flowing granular form with relatively high bulk density, without sintering, grinding, or briquetting, is disclosed. It involves the following steps:(a) forming a suspension of the carbonate in water with enough deflocculating agent, e.g., sodium polyacrylate or sodium hexametaphosphate, to substantially completely deflocculate the carbonate;(b) drying the resultant suspension at a temperature that is elevated, but without heating the carbonate to its sintering point, for example by spray drying in a spray drier operating at an inlet temperature in the range of about 400.degree. to 600.degree. C., to obtain a granular material primarily passing 10 mesh and held on a 150 mesh screen (Tyler); and(c) heating the granular material to about 600.degree. to 700.degree. C., which causes it to shrink, thereby increasing its bulk density by at least about 5%, preferably at least 10 or 20 percent.

Abstract: A glass manufacturing process using a granular, free-flowing form of alkaline earth metal carbonate, e.g., barium or strontium carbonate, is disclosed. The alkaline earth metal carbonate has a relatively high bulk density and is made without sintering, grinding, or briquetting. The carbonate is prepared from a fine particle size material by the following steps:(a) forming a suspension of the carbonate in water with enough deflocculating agent, e.g., sodium polyacrylate or sodium hexametaphosphate, to substantially completely deflocculate the carbonate;(b) drying the resulting suspension, at a temperature that is elevated, but without heating the carbonate to its sintering point, for example, by spray drying in a spray drier operating at an inlet temperature in the range of about 400.degree. to 600.degree. C., to obtain a granular material primarily passing 10 mesh and held on a 150 mesh screen (Tyler); and(c) heating the granular material to about 600.degree. to 700.degree. C.

Abstract: The invention relates to alkaline resistant glasses, particularly glass fibers, which comprise silica, calcia and at least one lanthanide series metal oxide effective to enhance the alkali resistance of the glasses.

Abstract: The invention described and claimed in the specification relates to the discovery that effective addition of Fe.sub.2 O.sub.3 to a lead phosphate glass results in a glass having enhanced chemical durability and physical stability, and consists essentially of the glass resulting from melting a mixture consisting essentially of, in weight percent, 40-66 percent PbO, 30-55 percent P.sub.2 O.sub.5 and an effective concentration up to 12 percent Fe.sub.2 O.sub.3.

Abstract: A filter cake formed of a glass precursor material and impregnated with a normally leachable toxicant can be heated, preferably with at least one other glass precursor material, at a sufficiently high temperature to form a molten composition which solidifies, upon cooling, to form a glass. The normally leachable toxicant becomes fixed within the glass rendering it substantially more non-leachable allowing for a more environmentally sound means for disposal, e.g., by landfill techniques. The process can be used to treat the arsenic sulfide-impregnated filter cake derived from the manufacture of food grade phosphoric acid.

Abstract: Wate asbestos is converted into a glass by maintaining within an electrical glass melting furnace a body of molten glass at a temperature above the decomposition temperature of asbestos; supplying asbestos to the furnace by a conveyor discharging above the body of molten glass so that the asbestos falls onto the molten glass and becomes decomposed and melted into glass; and withdrawing molten glass from the furnace at a temperature of at least 1000.degree. C. The asbestos is advantageously mixed with cullet and a melt accelerator and fed into the furnace by means of a screw mixer/conveyor. The furnace is advantageously operated at a pressure less than atmospheric pressure.

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: Platinum corrosion reducing amounts of a premelted oxide mixture that is PbO and B.sub.2 O.sub.3, or PbO and SiO.sub.2, or PbO, SiO.sub.2 and B.sub.2 O.sub.3 are added to raw batch ingredients for a lead-containing solder glass. All or part of the Pb.sub.3 O.sub.4 or PbO normally used in the raw batch is replaced for advantages including reducing the amount of platinum corrosion in a platinum melter used to melt the raw batch to provide the glass.

Abstract: The invention relates to glasses formed from naturally occurring zeolites which are modified by inclusion of additional alumina.

Abstract: A glass composition specially useful in the glass envelope of TV receiver tubes and which is of the lead silicate type is disclosed comprising in weight percent 30-65% SiO.sub.2, 20-40% PbO, 5-20% alkali metal oxides, 0-2% Al.sub.2 O.sub.3, 0-10% alkaline earth metal oxides, 0.2-2% Sb.sub.2 O.sub.3, and 0.1-0.5% CeO.sub.2. The improvement resides in employment of a novel refining system when the glass is formed which employs Sb.sub.2 O.sub.3, niter and CeO.sub.2 as the refining agents in particular weight proportions to reduce the seed count in the molten glass while also reducing thermal shock breakage when the solid glass product is thereafter thermally reworked.

Abstract: The invention relates to glasses formed from modified naturally occurring zeolites and in particular to alkaline-resistant glasses containing a high calcia loading.

Abstract: A refractory fiber composition and method for making refractory fiber from the composition. The refractory fiber composition includes kaolin clay as a source of alumina and silica to which is added zircon.

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 a preselected temperature. Thereafter, the melt is converted into fibers using conventional practices.

Abstract: SiO.sub.2 /MeO metallic silicates, wherein Me is lead or an alkaline earth metal, have a molar ratio of SiO.sub.2 to MeO of greater than 2, and same are well suited as pigments, fillers, and especially as glass-formers.

Abstract: The present invention relates to neutron-absorbent oxide or oxynitride glasses containing gadolinium and a process for their preparation.The glasses according to the invention, which incorporate silicon, aluminum, oxygen or oxygen and nitrogen, additionally contain gadolinium in a proportion of approximately 5 to 15 atom %.

Abstract: A glass composition is disclosed which is formed from a mixture comprising one or a plurality of natural mineral zeolites and having a melting point in the range of from about 1000.degree. to about 1500.degree. C. The glass compositions of this invention can be formed into various glass articles, including flat glass, glass containers, glass fiber and glass foam.

Abstract: Energy savings are attained by employing an organic liquid such as fuel oil as a glass batch wetting agent. Also, inclusion of fuel oil in a sulfur-containing glass batch yields improved melting rates.

Abstract: The dusting and segregation of the glass batch during the manufacture of opal borosilicate glass can be reduced by adding the phosphorus values to the glass batch as phosphoric acid, and calcium values as limestone, calcium carbonate or calcium oxide.

Abstract: An at least double silicate of an alkali metal and at least one other metal is prepared by interreacting (i) an aqueous solution of an alkali metal silicate and (ii) a solution of an oxide of such at least one other metal, or salt thereof, in the presence of (iii) a water-miscible polar organic liquid, whereby said at least double silicate is suspended in the organic reaction medium in insoluble and finely divided form. The separated product is an admirable glass-former.

Abstract: The chemical durability of alkali phosphate glasses is improved by incorporation of up to 23 weight percent of nitrogen. A typical phosphate glass contains: 10 to 60 mole % of Li.sub.2 O, Na.sub.2 O or K.sub.2 O; 5-40 mole % of BaO or CAO; 0-1 to 10 mole % of Al.sub.2 O.sub.3 ; and 40-70 mole % of P.sub.2 O.sub.5. Nitrides, such as AlN, are the favored additives.

Abstract: A glass having a composition which would result by mixing from 20 to 80 weight percent of glass A with 80 to 20 weight percent of glass B and melting the mixture to form a homogeneous glass:______________________________________ Glass A Glass B Weight Weight Percent Percent ______________________________________ SiO.sub.2 1.8-2.2 SiO.sub.2 67-70 B.sub.2 O.sub.3 14-16.5 Li.sub.2 O 14-17 PbO 69-72 Al.sub.2 O.sub.3 4-5.5 ZnO 8.2-9.2 CaO 9-12 BaO 2.7-3.5 ______________________________________said glass having a coefficient of thermal contraction from 15.degree. C. below the annealing point to room temperature of from 106 to 115.times.10.sup.-7 /.degree.C.

Abstract: A lead additive containing a lead oxide and an alkaline silicate which is resistant to dusting, abrasion and segregation. The weight ratio of lead to alkaline silicate, calculated as PbO and SiO.sub.2, respectively, is greater than about 95:5; the moisture content is less than or equal to about 2%; and the density is less than about 5 g/cm.sup.3.The process for producing these additives involve forming a paste of the lead oxide and alkaline silicate, conditioning the paste to form granules and heat treating the granules.

Abstract: A novel flux for glass compositions which is an eutectic mixture of lithium carbonate and sodium sulfate (liquidus temperature 496.degree. C.) is used in fiberizable glass compositions to improve fluidity and reduce the temperature of fusion of the raw materials of which the glass is formed.

Abstract: A method of manufacturing gel powder suitable for use as a starting material in the manufacture of hollow glass microspheres having a high concentration of silica. The powder is manufactured from a gel containing boron in the amount of about 1% to 20% (oxide equivalent mole percent), alkali metals, specifically potassium and sodium, in an amount exceeding 8% total, and the remainder silicon. Preferably, the ratio of potassium to sodium is greater than 1.5.