One can argue that the first step in any carbon management (or CO2 reduction) program should be maximizing the production efficiency for the amount of carbon that is already utilized and converted into CO2. The patent pending technology we term “BF Plus” can accomplish this through the integration of oxygen-enriched Blast Furnace (BF) hot metal production with high-efficiency power generation. By raising oxygen enrichment of the traditional Blast Furnace operations, and replacing a portion of the expensive charge coke with less-costly injected fossil fuels, the existing BF is turned into a producer of two valuable products: (i) molten iron, and (ii) higher-calorific-value fuel gas. The higher calorific value fuel gas can be converted into power with increased efficiency, thereby expanding the total quantity of value products for essentially the same amount of carbon input, while simultaneously reducing the cost of iron production. Such integration also enables the steelmaker to approach carbon dioxide reductions in a step-wise, and increasingly aggressive fashion: first by properly apportioning the CO2 emitted from the BF across the two value products of iron and power, next by the synergistic inclusion of CO2 capture before the power production step, and finally by the inclusion of a water gas shift step prior to CO2 removal. Each of these steps can be added or retrofitted into the BF Plus design when the economic and environmental drivers justify or require it. BF Plus thus gives a sensible approach to carbon management in steel industry ironmaking. Controlling blast furnace top gas quality to the requirements of the gas turbine is key, and this can be achieved by a number of methods including balanced injection of fossil fuels along with oxygen enrichment of the hot blast.
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