Abstract: A method of pyroprocessing mineral ores, such as iron ore. The method includes receiving a preheated product stream of iron-containing pellets at an infeed end of a rotary kiln and introducing an oxidizing gas into the tumbling bed toward the infeed end of the rotary kiln. Additionally, a combustible fuel is introduced through ports above the tumbling bed such that combustion of the introduced fuel increases the temperature of the product stream toward the infeed end. The increase in the temperature of the product stream allows the intensity of the flame from the centerline burner to be decreased, resulting in a reduction in the production of NOx. The apparatus for introducing both the oxidizing gas and fuel into the rotary kiln are common with each other.

Abstract: An industrial waste management facility (IWMF) for disposing of spent potlining includes a co-current gas-fired rotary kiln for containing a molten pool of spent potlining throughout the entire length of the rotary kiln from the inlet to the outlet, an ash quencher and cooler for receiving molten residue from the discharge end of the rotary kiln, a secondary combustion chamber, and a down-draft transition chamber for channeling discharge gases from the rotary kiln to the secondary combustion chamber. Pneumatic injection slingers feed and distribute spent potlining into the inlet end of the rotary kiln. A discharge dam provides a predetermined average depth of molten bath material in the rotary kiln over its entire length. A blended ratio of comminuted materials injected through the pneumatic injection slinger feeder is adjusted and controlled in response to signals received from a radiative optical kiln bath temperature measurement system.

Abstract: A traveling gate system for treating mineral ores that incorporate a cooling zone intermediate to heating zones to enable the use of a longer gate chain and additional heating zones to further refine the heat treating process of a traveling gate system. In the cooling zone the gas is forced upward to initially contact the gate chain and cool it and prevent the chain parts from exceeding their high temperature limit. Appropriate gases such as air can be selected for the cooling gas to further enhance the treatment of the material being processed on the gate chain.

Abstract: An industrial waste management facility (IWMF) for disposing of spent potlining includes a co-current gas-fired rotary kiln for containing a molten pool of spent potlining throughout the entire length of the rotary kiln from the inlet to the outlet, an ash quencher and cooler for receiving molten residue from the discharge end of the rotary kiln, a secondary combustion chamber, and a down-draft transition chamber for channeling discharge gases from the rotary kiln to the secondary combustion chamber. Pneumatic injection slingers feed and distribute spent potlining into the inlet end of the rotary kiln. A discharge dam provides a predetermined average depth of molten bath material in the rotary kiln over its entire length. A blended ratio of comminuted materials injected through the pneumatic injection slinger feeder is adjusted and controlled in response to signals received from a radiative optical kiln bath temperature measurement system.

Abstract: An industrial waste management facility (IWMF) for disposing of spent potlining includes a co-current gas-fired rotary kiln for containing a molten pool of spent potlining throughout the entire length of the rotary kiln from the inlet to the outlet, an ash quencher and cooler for receiving molten residue from the discharge end of the rotary kiln, a secondary combustion chamber, and a down-draft transition chamber for channeling discharge gases from the rotary kiln to the secondary combustion chamber. Pneumatic injection slingers feed and distribute spent potlining into the inlet end of the rotary kiln. A discharge dam provides a predetermined average depth of molten bath material in the rotary kiln over its entire length. A blended ratio of comminuted materials injected through the pneumatic injection slinger feeder is adjusted and controlled in response to signals received from a radiative optical kiln bath temperature measurement system.

Abstract: A method of pyroprocessing mineral ores. The method includes forming the mineral ore fines into small balls or pellets, drying and preheating the pellets and then subjecting the pellets to further heat with an oxidizing gas to substantially oxidize and indurate the pellets prior to discharging the pellets into a cooler. The essential equipment used in the process are machines such as a balling pan or drum for agglomerating the ore, a grate traveling through a furnace and a rotary kiln for transporting the pellets from the grate to a cooler. Also, means are provided to supply hot oxidizing gas to both the furnace and the kiln to heat the pellets. In addition, means are provided to supply an oxidizing gas beneath the tumbling bed of pellets in the kiln.

Abstract: An apparatus for directly reducing pellets of material without melting the material includes the transporting of the pellets through drying and preheating zones on an oxidizing traveling grate and reduction in a ported rotary kiln. There is a kiln having a first end and a second end with the first end being substantially adjacent to the heating and oxidizing component for receipt of the pellets therefrom. The kiln is inclined downwardly and is rotated to advance the pellets through the kiln from the first end to the second end therefrom. The kiln includes an induration zone for indurating the pellets. The induration zone is adjacent to the first end and remote from the second end and extends for a substantial portion of the kiln from the first end. The kiln includes a reduction zone extending from the downstream end of the induration zone to the second end. A device is used to inject a reducing agent into the reduction zone of its kiln for making contact with the pellets advancing through the reduction zone.

Abstract: An apparatus for directly reducing pellets of material without melting the material includes the transporting of the pellets through drying and preheating zones on an oxidizing traveling grate and reduction in a ported rotary kiln. There is a kiln having a first end and a second end with the first end being substantially adjacent to the heating and oxidizing component for receipt of the pellets therefrom. The kiln is inclined downwardly and is rotated to advance the pellets through the kiln from the first end to the second end thereof. The kiln includes an induration zone for indurating the pellets. The induration zone is adjacent to the first end and remote from the second end and extends for a substantial portion of the kiln from the first end. The kiln includes a reduction zone extending from the downstream end of the induration zone to the second end. A device is used to inject a reducing agent into the reduction zone of its kiln for making contact with the pellets advancing through the reduction zone.