Abstract: A vertical shaft melting furnace is operated in a method that includes firing a plurality of burners to generate combustion products, and directing jets of the combustion products into the shaft in a bottom region of the shaft. The method further includes directing a jet of hot gas into the shaft in an upper region of the shaft in a non-radial direction, whereby the jet of hot gas can induce a swirl to disperse a concentrated channel of combustion products rising from the bottom region to the upper region through a void in unmelted portions of a load of metal pieces in the shaft. The jet of hot gas directed into the upper region of the shaft can include recirculated flue gas, a mixture of air and recirculated flue gas, or combustion products that are generated by a burner. If the jet of hot gas includes combustion products that are generated by a burner, the burner is a secondary burner that preferably is fired into the shaft with a relatively low heat input.

Abstract: A submerged combustion vaporizer may include a premix burner with multiple integral mixers for forming premix and discharging the premix into the duct system that communicates the burner with the sparger tubes. The SCV may further include a NOx suppression system that injects a staged fuel stream into the exhaust in the duct system, and/or a NOx suppression system that mixes water with the premix.

Abstract: An apparatus for melting a metal load includes a furnace having a melting chamber with a hearth and a molten metal outlet. The apparatus further includes non-regenerative burners that are operative to fire into the melting chamber, and regenerative burners that also are operative to fire into the melting chamber. The method includes the steps of firing non-regenerative burners into the chamber to provide heat for melting the load, and also firing regenerative burners into the chamber to provide heat for melting the load.

Abstract: A vertical shaft melting furnace is operated in a method that includes firing a plurality of burners to generate combustion products, and directing jets of the combustion products into the shaft in a bottom region of the shaft. The method further includes directing a jet of hot gas into the shaft in an upper region of the shaft in a non-radial direction, whereby the jet of hot gas can induce a swirl to disperse a concentrated channel of combustion products rising from the bottom region to the upper region through a void in unmelted portions of a load of metal pieces in the shaft. The jet of hot gas directed into the upper region of the shaft can include recirculated flue gas, a mixture of air and recirculated flue gas, or combustion products that are generated by a burner. If the jet of hot gas includes combustion products that are generated by a burner, the burner is a secondary burner that preferably is fired into the shaft with a relatively low heat input.

Abstract: An apparatus includes a furnace structure defining a reaction zone. A burner structure communicates with the reaction zone through a burner port. The burner port is centered on a burner axis and has a radius. A fuel inlet structure communicates with the reaction zone through a fuel port. The fuel port is centered on a fuel port axis that is spaced radially from the burner axis a distance within a range from about twice the radius to about six times the radius. The fuel port axis is skewed relative to the burner axis to direct the fuel emerging from the fuel port to flow into the reaction zone along a spiral flow path.

Abstract: A plant pot assembly characterized by a container covered by a substantially impermeable cover such that water may be drawn upwardly through a capillary space between the covering and the container to irrigate a plant disposed within the container. The assembly also includes an outer enclosure which distills irrigation water, and which further aerates the growing medium within the container by forcing vapor saturated air into the medium. Due the combination of a capillary pumping action and an evaporation/condensation cycle, the plant pot assembly provides continuous irrigation for a plant at most ambient temperatures.