Abstract: In an apparatus for applying rock dust with foam to a mine wall to suppress mine fires and prevent explosions, foam and air-entrained rock dust are separately conveyed to a combination nozzle and mixing device. The air-entrained rock dust moves axially through a passage into an enlarged chamber while foam moves through an array of openings surrounding the passage that direct the foam in a helical path. The helical movement of the foam, and the reduction of the velocity of the air-entrained rock dust resulting from its movement into the enlarged chamber, enhance mixing. The mixture passes from the enlarged chamber through a restricted nozzle to increase the velocity of the mixture for effective spraying. The restricted nozzle has an array of internal flow-interrupting baffles that further promote mixing by generating turbulence, condense the stream, and shape the spray pattern.

Abstract: Rock dust is applied to a mine wall for mine fire suppression in combination with a chemical foam, by generating the foam from air and a foamable liquid in a mixing chamber, and delivering the foam through one flexible conduit and air-entrained rock dust through another flexible conduit to a portable assembly composed of a Y-joint and a delivery nozzle for combining the foam and rock dust and applying the combination directly to a mine wall.

Abstract: Rock dust is applied to a mine wall for mine fire suppression in combination with a chemical foam, by generating the foam from air and a foamable liquid in a mixing chamber, and delivering the foam through one flexible conduit and a suspension of rock dust in water through another flexible conduit to a combiner, and causing the combined foam, rock dust and water to pass through a flexible hose to a delivery nozzle from which it is applied to a mine wall.

Abstract: Rock dust is applied to a coal mine wall for mine fire suppression in combination with a chemical foam containing a saturated fatty acid, preferably stearic acid, which imparts hydrophobic properties to the rock dust particles, avoiding agglomeration. The rock dust and foam containing a saturated fatty acid are combined by causing the rock dust and foam to flow through separate conduits to a combiner from which the resulting mixture is caused to flow through a nozzle for application to the mine wall.

Abstract: Rock dust is applied to a mine wall for mine fire suppression in combination with a chemical foam, by generating the foam from air and a foamable liquid in a mixing chamber, and delivering the foam through one flexible conduit and a suspension of rock dust in water through another flexible conduit to a combiner, and causing the combined foam, rock dust and water to pass through a flexible hose to a delivery nozzle from which it is applied to a mine wall.

Abstract: Rock dust is applied to a mine wall for mine fire suppression in combination with a chemical foam, by generating the foam from air and a foamable liquid in a mixing chamber, and delivering the foam through one flexible conduit and air-entrained rock dust through another flexible conduit to a portable assembly composed of a Y-joint and a delivery nozzle for combining the foam and rock dust and applying the combination directly to a mine wall.

Abstract: Foams suitable for such uses as landfill coverage, frost protection, volatile emission control, gas control in mining, are composed of a hydrolyzable protein and a pre-gelatinized cationic modified starch along with other ingredients. The foam concentrate can be made at ambient temperature, is stable over time, can be easily tailored to achieve a desired foam stiffness and drain time characteristic over wide ranges, and can be easily diluted at ambient temperature to produce a foamable composition.

Abstract: Foams suitable for such uses as landfill coverage, frost protection, volatile emission control, gas control in mining, are composed of a hydrolyzable protein and a pre-gelatinized cationic modified starch along with other ingredients. The foam concentrate can be made at ambient temperature, is stable over time, can be easily tailored to achieve a desired foam stiffness and drain time characteristic over wide ranges, and can be easily diluted at ambient temperature to produce a foamable composition.

Abstract: Compositions useful in generating a foam particularly well adapted for use as a barrier are provided. These compositions contain keratin protein, a modified starch composed of at least 75% amylopectin, a ferrous ion component, and a dispersant.

Abstract: A composition for forming an essentially biodegradable foam for application to a substrate to provide a barrier between the substrate and the atmosphere formulated from a mixture in water of specified materials in certain proportional relationships. Its use in preparing such a foam barrier is also provided.

Abstract: Aqueous thixotropic foam-producing chemical compositions are presented which are comprised of an anionic sulfonate or sulfate surfactant, a fatty acid having 10-30 carbon atoms, an acrylic-based thixotropic thickener, an acrylic acid polymer processing aide and a base present in a concentration sufficiently high to neutralize all of the acid components of the mixture and adjust the pH to above 7.5. The thixotropic foam-producing compositions are useful for producing thixotropic foams which have the ability to resist slumping on sloped surfaces. Also disclosed is a process for mixing highly viscous, low density chemical foaming compositions with water without causing foaming of the resulting mixture.

Abstract: A foam generating apparatus is disclosed which generates foam from a foamable liquid by pumping the liquid by means of a high pressure pump from a storage tank to a combining device in which the liquid is combined with compressed air. The apparatus is capable of both operation and storage under extremely cold ambient conditions without the components of the apparatus becoming frozen. When the apparatus is not generating the product foam, a foamable liquid is recirculated throughout the apparatus to prevent the components of the apparatus from becoming frozen. The recirculation system is especially useful in preventing the high pressure pump from becoming frozen during storage in cold environments, while also reducing the amount of wear on the pump.

Abstract: In an apparatus for laying down a blanket of foam on a waste disposal landfill or the like, an enlongate manifold carried across the rear end of a vehicle delivers foam to nozzle assemblies which are spaced apart along the length of the manifold. Each nozzle assembly includes a holder in the form of a block with a first bore communicating with the manifold and bifurcating into second and third bores which communicate with nozzles having fan-shaped flat spray patterns. The axes of the bores generally define an inverted Y-configuration with the nozzle of the second bore arranged to spray the foam downwardly to one side and within a plane angled forwardly from a transverse vertical plane with respect to the direction of forward movement of the vehicle, and with the nozzle of the third bore arranged to spray the foam downwardly to the opposite side and within a plane angled rearwardly from the transverse vertical plane.

Abstract: An aqueous foamable membrane-forming composition comprised of a water dispersible polymeric latex, preferably styrene-butadiene latex, and an alkyl ether sulfate surface active agent. The composition desirably contains a alcohol having 12 to 14 carbon atoms, an acrylic acid polymer viscosity modifying agent and powdered carbon. Compositions of the invention in dilute aqueous form can be foamed and deposited on a surface to be covered, such as a landfill. Upon standing, the foam develops into a substantially stable, weather resistent membrane.

Abstract: A method of forming a temporary barrier between a substrate and the atmosphere by applying to the substrate a layer of foam generated from an aqueous composition comprising specified agents. Certain compositions especially adapted for this purpose are also provided.