Abstract: A heavy medium low-specific gravity method for recovering coarse clean coal within a size range of about +28 m and fine clean coal and coal-bearing particles within a size range of -28 x Om from a raw coal feed wherein heavy medium is recovered as a substantially clean product which can be recycled in the heavy medium system. In the method a raw coal feed containing coal, shale and other impurities within a size range of about 3.81 cm.times.0 is mixed withi a heavy medium to produce a slurry of low specific gravity between about 1.27 and 1.70. The slurry is treated in at least one cyclone to separate an overflow product containing substantially all coal and coal-bearing particles from an underflow product containing all shale and sulfur-bearing rejects.The overflow product is treated on standard equipment to separate coarse coal from fine coal and heavy medium. The coarse coal is recovered as a usable product.

Abstract: A method for maintaining a uniform stable operation of a blast furnace susceptible to erratic behavior because of large disturbances introduced into the furnace is described. The method includes:(a) determining a high temperature heat parameter (HTH) over a predetermined period of time,(b) determining a CEEP parameter over a predetermined period of time,(c) comparing the differences between the HTH and the CEEP parameters and their respective averages during selected time periods of operation, and(d) changing the temperature and/or moisture content of the hot blast air dependent upon the values in step (c).

Abstract: Apparatus for monitoring the depth of granular material in a container or on a carrier includes a unique probe tip and complementary apparatus, which includes a support, a positioning mechanism and a cleaner, to which the tip is fastened. The probe tip is comprised of an electrically conductive metallic strip having a metallic grid attached to one end and electrical connections at the opposite end for electrically connecting the strip to electronic equipment. The strip is enclosed in an electrically insulating sheath. A section of the sheath having a known surface area and thickness and contiguous with the metallic grid is filled with electrically conducting material. The ratio of the surface area of the section to its thickness is not less than about 20. The section has a thickness of not more than about 1.0 centimeter. The electrical resistivity of the section can be between about 0.1 and 10 megohms/cm.sup.2.

Abstract: A process for producing mineral wool having a chemical composition comprised of between about 50 and 70 weight percent silica plus alumina, about 20 and 35 weight percent lime plug magnesia and about 5 and 15 weight percent iron oxides is described.The process includes feeding a first particulate waste material having a particle size of 100 weight percent -200 mesh and containing organic combustibles having heating values of about 10 mega J per kilogram of slag and inorganic non-combustibles, a second particulate waste material having a particle size of 100 weight percent -200 mesh and containing fluxstone, and preheated air at a velocity of between about 30 meters to 60 meters per second at a temperature of about 500.degree. C. into a high temperature cyclone-like furnace. The combustibles are substantially instantaneously burned and the non-combustibles and the fluxstone are melted and reacted to form a molten slag which can be fiberized into mineral wool.

Abstract: A hydrostatic extrusion apparatus whereby thermoplastic polymers can be hydrostatically extruded in a solid state is described. The apparatus includes:(a) an outer casing or tooling support means,(b) a container assembly concentrically contained within the outer casing and having pressure means attached thereto to provide extrusion pressure to a fluid in the assembly, sealing means to prevent leakage of the fluid, means for holding a polymer billet and including a die portion, and(c) a receiver assembly axially aligned with the container assembly concentrically within the outer casing having pressure means to clamp the container and receiver assemblies together, a mandrel for holding and aligning a mandrel-head in spaced relationship with the die, and means for receiving, lubricating and cooling the extrudate.Optionally, means for preheating and loading the polymers into the container assembly are provided whereby the press may be operated on a semi-continuous or continuous basis.

Abstract: The invention is directed to biaxially oriented thermoplastic polymer flexible film having a substantially uniform thickness between about 0.005 and 0.030 of an inch (0.13 mm and 0.76 mm) and characterized by a structure comprised of discrete, platelet-like spherulitic crystalline aggregates compressed transversely to the plane of the film and biaxially oriented in the plane of the film and having a combination of improved properties and also to a rigid conduit or extrudate having a plurality of thermoplastic crystalline polymer layers each of which has a unique microstructure and improved properties.

Abstract: A thick-walled, seamless, rigid conduit having a substantially uniform wall thickness which is not less than about 0.5 percent of the outside diameter consisting essentially of an oriented crystalline thermoplastic polymer characterized by a structure comprised of radially compressed discrete, platelet-like spherulitic crystalline aggregates and having a combination of good ultimate tensile strength and low temperature tensile impact strength is described.The conduit is fabricated by solid state hydrostatic extrusion of a substantially non-oriented semi-crystalline thermoplastic polymer preform which may contain up to about 60 weight percent filler. The polymer is substantially simultaneously elongated in both circumferential and axial directions by compressive forces with the circumferential elongation being at least 100 percent.

Abstract: A method for measuring the thickness of a refractory laid-up against the interior surface of the steel shell of a metallurgical apparatus includes placing at least one monitoring device in a critical wear area of the apparatus in a manner such that the free end of the device is at a known distance from the hot face of the refractory and the confined end extends beyond the outer surface of the steel shell. The device is connected to an electronic time-domain reflectometer by electrical connecting means. Timed pulses are generated and impressed in the device by the instrument and reflections of the pulses are received by and are visually displayed on the reflectometer. The length of the device appears on the display as a straight line bounded by two inflections. The straight line is indicative of the thickness of the refractory.The device includes a metallic conductor coaxial with an outer metallic sheath and separated therefrom by a refractory having a desired dielectric constant.

Abstract: A method for treating a water slurry of granulated blast furnace slag containing particles of granulated slag having a size consist of about 0.635 centimeter .times. 0 (1/4 inch by 0) wherein a size separation of the particles is made at about 100 sieve. The sink fraction i.e. coarse particles larger than 100 mesh are partially dewatered and thermally dried prior to being comminuted with raw materials to make portland blast furnace slag cement. The float fraction i.e. fine particles smaller than 100 mesh can be used as is or partially dried prior to being used as an additive or extender for a cementitious material in the production of concrete products.

Abstract: Molten blast furnace slag is quenched by a volume of water divided into two streams. The first stream is directed downwardly against the slag while the second stream is directed horizontally against the slag. The molten slag is broken down into relatively fine sand-like granules which are kept submerged in the water. The vapors formed during granulation are substantially free of detectable SO.sub.2 and the H.sub.2 S formed and vented to the atmosphere is insufficient to be a detriment to the surrounding environment.

Abstract: An improved method for producing calcined coke agglomerates having good stability including adjusting the fluidity of coals or blends of coals to within a range of 1300 DDPM and 3000 DDPM, mixing the coals or blends of coals with char and optionally topped tar in a rotating agglomerating drum and agglomerating the mixture at a temperature between 750.degree. F. and 875.degree. F. (399.degree. C.and 468.degree. C.) for a time to form partially coked green coal agglomerates generally spherical in shape and calcining the partially coked green coal agglomerates at a temperature between 1500.degree. F. and 2000.degree. F. (815.degree. C. and 1093.degree. C). The calcined coke agglomerates are characterized by having a stability of not less than 60%.

Abstract: A method for preparing a steel mill waste material comprised of inner metallic cores encased in outer shells of iron oxides for use as size-graded metallic abrasives and the product so produced are described.The waste material is screened to simultaneously separate it from all the foreign matter collected therewith and also to separate it into a fraction containing particles larger than about 6.35 mm and a fraction containing particles smaller than about 6.35 mm. The fraction containing the particles larger is recycled in the steel mill. The fraction containing the smaller particles is charged into a grinding mill containing appropriate grinding media. The smaller fraction remains in the mill for a time so that the outer shells are broken into small pieces substantially all of which are removed from the surfaces of the inner cores. The pieces of the shells and the metallic cores are separated from each other by screening. The metallic cores are graded into a plurality of sizes by screening.

Abstract: A process for producing calcined coke agglomerates characterized by having a low reactivity to carbon dioxide. The process includes calcining green coal agglomerates at a temperature within the range of 1700.degree. F. to 1950.degree. F. (927.degree. C. to 1066.degree. C.) in a calciner. The agglomerates are exposed to a gaseous atmosphere which before cracking contains not less than 20% by volume of at least one straight chain aliphatic hydrocarbon gas containing one to four carbon atoms. The gaseous atmosphere is preheated to a temperature within the range of 200.degree. F. to 700.degree. F.(93.degree. C. to 371.degree. C.) prior to being introduced into the calciner. Carbon produced when the hydrocarbon gas is cracked, is deposited as vitreous carbon on the surfaces, in the fissures and in the pores of the agglomerates. The calcined coke aggglomerates discharged from the calciner have a reactivity to carbon dioxide of between 2% to 8%.

Abstract: A mixer block used in rotary drums to improve the efficiency of mixing, drying, cooling, heating, or calcining of solid materials such as gravel, stone, fluxes and the like to produce a more uniform product with minimal production of fines and dust is described. The mixer block is especially useful when used as part of the refractory lining in a rotary kiln to calcine fluxstone such as limestone, dolomite, dolomitic limestone, magnesite and the like.

Abstract: A non-toxic abrasive material used to manually blast clean the surface of ferrous metals prior to painting comprised of generally spherical particles containing 85% iron, the remainder being substantially oxygen and minor amounts of elements usually found in carbon and alloy steels, and having a metallic core containing 30% to 50% of the iron as metallic iron surrounded by a shell containing the remaining 50% to 70% of the iron as iron oxides. The abrasive material is characterized by having a specific gravity of 5 to 6 and a bulk density of 180 pounds per cubic foot (2.88 grams per cubic centimeter). It is preferred to use particles within the size range of -6,+100 mesh for manual blast cleaning purposes, however particles which are -100 mesh size can be used in special applications.

Abstract: Green balls suitable for charging into a metallurgical furnace characterized by having sufficient strength to resist degradation during transport and charging into said furnace, made by agglomerating iron-bearing fume produced in steelmaking furnaces.

Abstract: A method for preparing moist iron-bearing fume for use in steelmaking furnaces to recover the iron contained in the fume. The fume is thickened, substantially instantaneously dried, impact-fractured and balled. Moisture is added to the fume on the balling device to bind the fume to produce "green" balls which resist degradation during handling and transport. The "green " balls have sufficient strength to resist degradation during handling prior to and during charging to steelmaking furnaces.

Abstract: A method for preparing strong, stable "green" balls of dry-collected iron-bearing fume, which contains not less than about 8% combined amount of lime (CaO) and magnesia (MgO). The fume is charged to a balling device where there is added to the fume a quantity of water equal to both the stoichiometric amount required to completely hydrate such lime and magnesia and to produce in the "green" balls a water content between about 7%-12%. The residence time of the fume on the balling device is not less than about 8 minutes.

Abstract: Green balls suitable for charging into a metallurgical furnace characterized by having sufficient strength to resist degradation during transport and charging into said furnace, made by agglomerating iron-bearing fume produced in steelmaking furnaces.

Abstract: A polyolefin composition having a high level of impact resistance and high temperature flow resistance comprising 30 to 90 weight percent resin containing greater than 50 to less than 75 weight percent of polyolefin and greater than 25 to less than 50 weight percent elastomer, and 10 to 70 weight percent filler.