Blast furnace iron production with integrated power generation

#This particular invention relates to enriching air supplied to a coal-injected iron-making blast furnace and using the flue or top gas from the furnace to generate power.

#Methods for combining iron production and power generation are described in “Oxygen blast furnace and combined cycle (OBF-CC)—an efficient iron-making and power generation process”, Y. Jianwei et al., Energy 28 (2003) 825-835.

#Air Separation Units (ASUs) and methods for making oxygen therein are described in U.S. Pat. No. 5,268,019; hereby incorporated by reference. Methods for combining iron making process with an ASU are described in U.S. Pat. No. 5,582,029 and WO 9728284-A1.

#FIG. 1 is a schematic illustration of one aspect of the invention that employs coal gasification and combined cycle power generation in connection with Blast Furnace iron production.

#FIG. 2 is a schematic illustration of another aspect of the invention that employs coal gasification and combined cycle power generation and carbon dioxide capture and removal (for possible sequestration) in conjunction with Blast Furnace iron production.

#FIG. 3 is a schematic illustration of yet another aspect of the invention that employs coal gasification and combined cycle power generation together with carbon dioxide capture and removal (for possible sequestration) that is enhanced by the inclusion of a shift reactor prior to the carbon dioxide capture and removal step.

#The apparatus, components, systems and methods illustrated in these Figures can be employed individually or in combination to obtain additional aspects of the invention that are not illustrated by the Figures.

#The instant invention relates to apparatus, processes and compositions for providing an integrated system that utilizes oxygen enrichment of air supplied to a blast furnace (e.g., via an ASU) to efficiently combine coal gasification and blast furnace iron production. The integrated system gasifies coal in situ within the iron blast furnace and produces a flue or furnace top-gas having improved utility for power generation and, if desired, from which carbon dioxide can removed and sequestered.

#Additional oxygen beyond that which is normally supplied to the air blast is either directly injected or combined with the blast air being supplied to the blast furnace to enhance the effectiveness of the blast furnace to accept a relatively large amount of injected fossil fuels, for example coal from a pulverized coal injection system (PCI), and/or to enable more pulverized coal to be injected. Such a PCI system reduces the amount of coke that is required for iron production in a blast furnace. In addition, supplying oxygen enriched air to the blast furnace can produce: 1) a flue or top-gas that has reduced nitrogen content and increased fuel or calorific value, 2) a top gas that has enhanced value for power generation, 3) a top gas that is compatible with gas turbine power generators, 4) a top gas obtained by in situ coal gasification within the blast furnace, among other benefits. In a marked improvement over conventional methods, the integrated system of the instant invention obtains a top gas that can have an increased concentration of hydrogen and carbon monoxide and, in some cases, a reduced amount of nitrogen.