Abstract: An improvement in a method for the batchwise gaseous reduction of iron ore to sponge iron in a multiple unit reactor system including a cooling reactor and a series of reduction reactors. Reduction is effected with a gas composed largely of carbon monoxide and hydrogen generated by reforming a mixture of steam and natural gas or other gaseous hydrocarbons at an elevated temperature. The reducing gas pressure drop through the system is decreased by using an out-of-line cooling reactor and cooling gas loop, thereby making it feasible to use three or more reduction reactors in series and thus enhance the efficiency of utilization of the reducing gas. Also the use of an out-of-line cooling reactor permits independent control of both the gas flow rate and gas composition in the cooling loop.

Abstract: A method for inhibiting carburization of metal-bearing material in the reduction zone of a vertical shaft, moving bed reactor for the direct gaseous reduction of iron ore to sponge iron. Carburization within the reduction zone is decreased by regulating the water vapor content of the reducing gas in any of various ways, e.g., by adding water vapor in the form of steam to the reducing gas either before it enters the reduction zone, while it is within the reduction zone, or after it leaves the reduction zone or by recirculating a portion of the effluent gas from the reactor and cooling the recirculated gas to a predetermined extent.

Abstract: A method and apparatus for measuring the percentage reduction of iron ore in a reduction reactor of a multiple reactor gaseous reduction system. In accordance with a preferred embodiment, the flow and composition of the reducing gas fed to the reduction reactor and the flow and composition of the reactor effluent gas after cooling are measured and the measurements are fed to a computer along with data on the initial weight of the charge to the reactor, the moisture content of the charge and the initial reducible oxygen in the charge. The computer is programmed to compute the rate of oxygen removal from the charge, integrate the rate of removal with respect to time and compare the integral with the initial oxygen content of the charge to evaluate percentage reduction thereof.

Abstract: An improvement in a method for the batchwise gaseous reduction of iron ore to sponge iron in a multiple unit reactor system including a cooling reactor and at least one reduction reactor. Reduction is effected with a gas composed largely of carbon monoxide and hydrogen which may be, for example, generated by reforming a mixture of steam and natural gas or other gaseous hydrocarbons at an elevated temperature. The reducing gas requirement of the system is decreased by adding to the gas fed to one or more of the reduction reactors a minor amount of a hydrocarbon gas or vapor, e.g., natural gas, methane or a combination of methane and recycled spent reducing gas.

Abstract: An improvement in a method for the batchwise gaseous reduction of iron ore to sponge iron in a multiple unit reactor system including a cooling reactor and a series of reduction reactors. Reduction is effected with a gas composed largely of carbon monoxide and hydrogen generated by reforming a mixture of steam and natural gas or other gaseous hydrocarbons at an elevated temperature. The reducing gas pressure drop through the system is decreased by using an out-of-line cooling reactor and cooling gas loop, thereby making it feasible to use three or more reduction reactors in series and thus enhance the efficiency of utilization of the reducing gas.Also the use of an out-of-line cooling reactor permits independent control of both the gas flow rate and gas composition in the cooling loop.

Abstract: A process for the direct gaseous reduction of iron ore to sponge iron wherein the sponge iron is cooled with a carbon-containing cooling gas by a dual temperature procedure that increases transfer of carbon from the cooling gas to the sponge iron and thereby permits the production of a product having a combination of relatively low or moderate metallization and relatively high potential metallization. Increased productivity of the direct reduction plant and of the overall integrated steel plant are achieved.