Abstract: A method is provided for treating diatomaceous earth filteraids having a beer-soluble iron content of less than about 0.01% to further reduce the beer-soluble iron content by maintaining the filteraids in contact with a relatively small volume of an acid. In the filteraids so produced, the beer-soluble iron content can be reduced by as much as 70% to 100%. In making the filteraids of this invention, sulfuric acid in about 0.1 to about 3.0 normal solution can be used to treat the starting filteraids.

Abstract: A method of increasing the magnesia content in dolomite sinter produced from dolomite. Crushed dolomite is calcined to form a physical mixture of particulate magnesium oxide (MgO) and calcium oxide (CaO) and the mixture is hydrated to develop a size differential between the calcium hydroxide and the magnesium hydroxide. The hydroxides are dried without dehydration and separated into two component portions on the basis of size. One portion of the mixture is rich in Ca(OH).sub.2 and the other is rich in Mg(OH).sub.2. The portion of the mixture primarily comprised of Mg(OH).sub.2 is then calcined to form the synthetic sinter.

Abstract: A splicing strip is provided comprising a pair of mastic layers and a porous, flexible reinforcing sheet with the mastic layers in adherent contact through openings in the reinforcing sheet. A release sheet is attached to at least the outside face of one of the mastic layers, and a sheet of non-tacky material is attached to the outside face of the other of the mastic layers.

Abstract: A furnace for firing refractory ware including a vertically movable bell adapted to enclose a car of refractory ware. Means is provided to seal the enclosure defined by the bell, to evacuate air from the sealed bell enclosure, and to deliver a fluidized, chemically inert, non-combustible, high thermal absorption material to the evacuated bell. A plurality of lasers are provided on the bell facing spaced locations therein and are adapted to be fired sequentially. When fired, the light and heat energy from each laser beam is diffused and absorbed by the inert material and is then re-radiated throughout the bell enclosure to fire the refractory ware therein.

Abstract: A construction material in sheet form having at least two water barriers including a water-impermeable foamed intermediate layer, a mineral-based interior layer, and a prefinished, weatherable, water-impermeable non-asphaltic outer layer, with adjoining layers firmly adhered. Sheets of the construction material having a foamed intermediate layer and mitered edges exposing the foamed layers are joined by the steps of positioning the sheets with the mitered edges abutting opposite sides of the stem of a bulb-T rafter, the sheets being supported by the cross-member of the bulb-T rafter, forming a foam filler in the cavity created by the abutted mitered edges, and sealing the cavity with weatherable tape. A roof deck for use with bulb-T rafters, the roof deck constructed of the aforementioned sheets joined by the aforementioned method is also shown.

Abstract: A process is described for making shaped refractories by impregnating cold pitch-bonded shaped refractories with a liquid composition comprising hot pitch.

Abstract: A system for joining and adhering a pair of abutting panels to a rigid substrate and providing a seal against thermal and moisture transfer. The system is comprised of an elongated receptacle member with a base and a pair of spaced vertical elements extending upwardly from the base and forming a channel, to be placed under and between edges of the panels to be joined. The receptacle member is firmly attached to the rigid substrate by fastening means passed through the base. The adjacent side walls of the vertical elements include a plurality of vertically spaced, downwardly angled teeth projecting inwardly towards the center of the channel. An elongated resilient insert member includes a cap and a projection extending downwardly from said cap.

Abstract: Apparatus for sealingly joining sheets of construction material laid with edges abutting over an underlying frame and having edges rabbeted to form a joint channel including a pad for lying in the channel, a cap permanently adhered to the pad member and having edges extending past the pad for sealingly contacting the unrabbeted sheet surfaces, a metal strip embedded in the pad, and screws for securing the metal strip to the frame to capture the rabbeted surfaces of the sheets.

Abstract: A method and apparatus for selectively comminuting particles of a frangible material for the production of filter aid, the apparatus including an air-conveying system for carrying entrained particles of varying masses, a venturi for accelerating the air stream and entrained particles, a duct for receiving the accelerated air stream and particles, and impact bars mounted in the duct for selectively fragmenting the entrained particles. The impact bars are positioned in the accelerated air stream to establish adverse pressure fields which classify the entrained particles and which provide impact surfaces to fragment particles greater than a predetermined mass, the rest of the particles being deflected around the bars by the action of the adverse pressure fields.

Abstract: Unfired, refractory compositions are provided containing a refractory material of magnesia, dolomite, lime or mixtures thereof, a carbonaceous binder, and elementary carbon. The amount of elementary carbon incorporated in the composition is controlled and depends on the amount of Fe.sub.2 O.sub.3 present in the refractory material. The compositions are provided with at most 1.5% elementary carbon if the Fe.sub.2 O.sub.3 content is below 0.5%; at most 1.75% elementary carbon if the Fe.sub.2 O.sub.3 content is 0.5 to 2.5%, at most 2.0% elementary carbon if the Fe.sub.2 O.sub.3 content is above 2.5 to 4.5%, and at most 2.5% elementary carbon if the Fe.sub.2 O.sub.3 content is above 4.5%. Refractory shapes and bricks produced from these refractory compositions where the amount of elementary carbon is controlled according to the Fe.sub.2 O.sub.

Abstract: This invention provides improved high fired direct bonded basic magnesite-chrome refractory shapes, such as brick, characterized by the presence of chromium enriched spinel structures distributed in the matrix and bonding the individual periclase crystals. The shapes are thermally stable and resistant to slag penetration and erosion and enjoy improved service life in industrial furnace linings. Also provided is a method of making the improved refractory shapes which comprises forming a mixture of (1) from about 40% to about 75% by weight high purity magnesite, (2) from about 25% to about 60% by weight chrome ore and (3) from about 0.5% to about 10% by weight chromic oxide powder; pressing the mixture into a refractory shape; and firing the refractory shape to a temperature of at least 1700.degree. C.

Abstract: This invention relates to the manufacture of lime-silica bonded structural materials particularly suitable where structural materials having thermal insulation properties are desired. More specifically, the invention relates to new and improved methods of manufacturing lime-silica bonded structural materials having high modulus of rupture and high compressive strength.

Abstract: A binder composition comprising pitch, an aqueous solution of a water soluble resin, and an organic solvent solution of a thermosetting polymer. The binding composition in combination with particulate refractory aggregate forms a molding composition suitable for use in making shaped refractory articles. Shaped refractory articles prepared from such a molding composition are particularly suitable for use as linings in basic oxygen process steel refining vessels. Shaped refractory articles may be prepared by coating coarse refractory aggregate with the organic solvent solution of a thermosetting polymer, admixing powdered pitch with the coated coarse refractory aggregate, blending fine refractory aggregate and the aqueous solution of the water soluble resin with the coated refractory aggregate-pitch mixture, and forming the resultant composition into shaped refractory articles.

Abstract: Method for the production of cement-bonded molded articles, particularly lightweight boards of wood fiber, wood chips or other lignocelluloses, of mineral fibers, glass fibers, plastic chips and fibers or various lightweight materials, like expanded silicates, expanded clay or expanded glass or granules of foamed plastics as a base material and portland cement as a binder, characterized in that the molded articles are produced in a heated molding duct formed of endless moving belts, for example, steel belts, using a portland cement as a binder in the molding compound which contains 1 to 30% by weight, perferably 15 to 25% by weight, of a calcium-halogen aluminate of the composition 11CaO.7Al.sub.2 O.sub.3.CaX.sub. 2 wherein X is any halogen. The cement with added calcium-halogen aluminate has such a short setting time, which is further accelerated by heating during molding, that boards may be successfully made on a continuous basis using a belt-molding machine.

Abstract: Burned magnesite bricks are impregnated with an aqueous dispersion of carbon black, and then dried using hot dry air at a temperature above about 100.degree.C.

Abstract: Monolithic acoustical panels are provided including relatively coarse particles of expanded volcanic glass, such as perlite, and mineral fiber. The panel provides a highly porous structure that possesses desirable noise suppression characteristics, and comprises by weight 45 to 75% of an expanded volcanic glass of which 65-100% will pass an 8 mesh U.S. Standard screen and will be retained on a 50 mesh U.S. Standard screen; 10 to 30% of mineral fiber; 10 to 20% of nongelatinous cellulosic fiber having lengths in the range of about 0.5 to 3.5 mm.; and a total of 10 to 25% of binder and sizing agent.

Abstract: Improved periclase refractories are prepared by using an alkyd resin binder for tempering and pressing periclase grains into refractory shapes such as bricks. The pressed shapes are dried and fired. After firing, the refractory shapes are impregnated under vacuum with molten pitch and can then be used as lining in basic oxygen steelmaking furnaces. The fired refractory bricks have a greatly improved modulus of rupture at 1482.degree.C. of 3000-4000 p.s.i. The alkyd resin is generally incorporated in amounts of 2.5 to 4.5 weight percent.The green strength of the alkyd resin bonded bricks can be improved by adding a strong organic acid to the alkyd resin prior to mixing it with periclase grains. The green strength of bricks produced from such a mixture is between 30 and 40 p.s.i.

Abstract: Sintered ceramic articles having a high surface area-to-weight ratio and containing a plurality of ducts that extend through the article to permit fluid flow therethrough are prepared by forming an extrudable admixture of pulverized ceramic material. The admixture is forced through a forming zone in which initial shearing forces form the admixture into a plurality of discrete ribbons, and the discrete ribbons are flowed into the upstream ends of a plurality of spaced, longitudinally-extending members to form a web member containing a plurality of longitudinally-extending ducts as the ribbons flow together about the members.