método de alimentação de carga em um alto-forno

The present invention proposes a method for feeding a burden to a blast furnace (32), wherein the method comprises providing a charging device (38) having at least one material hopper (40), the material hopper (40) comprising a hopper chamber (42), a material inlet aperture for feeding a burden into the hopper chamber (40), and a material discharge aperture for feeding a burden from the hopper chamber (40) to the blast furnace (32); the material inlet aperture having an associated inlet seal valve 44) for opening and closing the material inlet aperture and the material discharge aperture having an associated material discharge valve (46) for opening and closing the material discharge aperture. The method further comprises opening the material inlet aperture and closing the material discharge aperture; feeding a burden into the hopper chamber (40) through the material inlet aperture; closing the inlet seal valve (44); pressurizing the hopper chamber (40) by feeding pressurizing gas into the hopper chamber (40); and opening the material discharge valve (46) and feeding the burden from the hopper chamber (40) to the blast furnace (32). According to an important aspect of the invention, the method further comprises subjecting at least a portion of a top gas recovered from the blast furnace (32) to a recycling process wherein carbon dioxide is removed from the recovered top gas; and feeding at least a portion of the recovered carbon dioxide as pressurizing gas into the hopper chamber (40) for pressurizing the hopper chamber (40).