A direct reduction plant is disclosed. The direct reduction plant includes an oxygen injection system, a reformer, and a shaft furnace. The oxygen injection system includes an oxygen injection reactor and a main oxygen burner. The oxygen injection reactor is adapted to receive a gas mixture. The main oxygen burner is adapted to increase a temperature of the gas mixture by burning a mixture of fuel and oxygen fed to the main oxygen burner. The reformer is adapted to reform the gas mixture with the increased temperature. The shaft furnace is adapted to reduce iron ore using the reformed gas mixture.