Patent ID: 11920204
Assignee: MIDREX TECHNOLOGIES, INC.
Field: Materials, metallurgy (Chemistry)
Classification: CPC C  F  Y | IPC C  F

Claim 6:
7. A method for a direct reduction process for direct reduced iron, comprising:
feeding a gas mixture into an oxygen injection system;
heating a gas mixture comprising natural gas and compressed shaft furnace top gas in a heat exchanger to form a pre-heated gas mixture at about 560°C. prior to feeding the pre-heated gas mixture to an oxygen injection system, wherein the oxygen injection system is positioned between the heat exchanger and a catalytic reformer, and the catalytic reformer is positioned downstream of the heat exchanger;
further increasing a temperature of the pre-heated gas mixture in the oxygen injection system to about 700° C. or above, to mitigate a risk of Boudouard carbon deposition at the catalytic reformer, by burning a fuel and oxygen;
discharging the pre-heated gas mixture with the increased temperature from the oxygen injection system directly to the catalytic reformer;
reforming the pre-heated gas mixture with the increased temperature in the catalytic reformer to produce a reformed gas mixture;
providing the reformed gas mixture directly to a shaft furnace; and reducing iron ore in the shaft furnace using the reformed gas mixture.