Plant and method for the thermal treatment of solids

A method for the thermal treatment of iron containing oxide, in which fine-grained solids are heated in a preheating calcining stage and are exposed to a reduction gas in a subsequent reduction stage, wherein off-gas from the reduction stage is guided through a separation device, separating the water originating from the reduction stage, wherein off-gas from the preheating calcining stage is guided through a venturi scrubber and a packed bed section downstream of the venturi scrubber to condense water vapor, wherein the water separated in at least one separation device is recycled into a water treatment section, from which the recycled water is supplied to a water electrolysis plant and/or a steam reforming plant producing hydrogen, and that the produced hydrogen is supplied to the reduction stage as reductant and/or to the preheating calcining stage as fuel and/or to the gas heater as fuel and/or from which the recycled water is supplied to at least one separation device as process water, wherein the process water exchanges heat with the off-gas, is cooled in the water treatment section and is recirculated to the separation device.

A plant for the thermal treatment of iron containing oxide comprising a preheating calcining stage, for heating up fine-grained solids and a reduction stage, for reducing the heated solids by exposure to a reduction gas comprising hydrogen, wherein an off-gas outlet of the reduction stage is connected to a separation device to condense water vapor from the off-gas of the reduction stage, wherein an off-gas outlet of the preheating calcining stage is connected to a venturi scrubber and a packed bed section arranged downstream of the venturi scrubber to condense water vapor wherein a water outlet of at least one separation device is connected to a water treatment section for recycling the water, that the water treatment section is coupled to a water electrolysis plant and/or a steam reforming plant producing hydrogen as a reductant for the reduction stage and/or as a fuel for the preheating calcining stage and/or to the gas heater as fuel and/or that the water treatment section is coupled to at least one separation device to provide process water, which exchanges heat with the off-gas, is cooled in the water treatment section and is recirculated to the separation device.