Method for operating a blast furnace plant

A method for operating a blast furnace plant that comprises a blast furnace, at least one material hopper for charging raw materials to the blast furnace, having an upper seal valve and a lower seal valve, and at least one hot stove that produces hot blast for the blast furnace, the method comprising at least one charging cycle with the following steps:

• opening the upper seal valve,
• introducing raw materials into the material hopper,
• closing the upper seal valve,
• pressure equalization of the material hopper with blast furnace top pressure, and
• opening the lower seal valve to discharge the raw materials into the blast furnace, wherein an offgas from the at least one hot stove is transferred by a transfer system to the at least one material hopper and the offgas is injected into the material hopper and the material hopper is pressurized to blast furnace top pressure before the lower seal valve is opened and the raw materials are discharged into the blast furnace, wherein the offgas is injected to constitute at least 70% v/v of a gas inside the material hopper when the lower seal valve is opened.