Loading patent…
AssigneeOutotec Oyj
InventorsMartin Hirsch, Michael Ströder, Peter Weber
Estimating the term…
A method for the heat treatment of solids containing iron oxide, in which fine-grained solids are heated to a temperature of about 630° C. in a fluidized-bed reactor (1). To improve the utilization of energy, it is proposed to introduce a first gas or gas mixture from below through a supply tube (3) into a mixing chamber (7) of the reactor (1), the gas supply tube (3) being at least partly surrounded by a stationary annular fluidized bed (10) which is fluidized by supplying fluidizing gas. The gas velocities of the first gas or gas mixture and of the fluidizing gas for the annular fluidized bet (10) are adjusted such that the Particle-Froude-Numbers in the gas supply tube (3) are between 1 and 100, in the annular fluidized bed (10) between 0.02 and 2, and in the mixing chamber (7) between 0.3 and 30.
A method for the heat treatment of solids containing iron oxide, in which fine-grained solids are heated to a temperature of about 450 to 950° C. in a fluidized-bed reactor, wherein a first gas or gas mixture is introduced from below into a mixing chamber region of the reactor through a preferably central gas supply tube, the gas supply tube being at least partly surrounded by a stationary annular fluidized bed which is fluidized by supplying fluidizing gas, and the gas velocities of the first gas or gas mixture and of the fluidizing gas for the annular fluidized bed are adjusted such that the Particle-Froude-Numbers in the gas supply tube are between 1 and 100, in the annular fluidized bed between 0.02 and 2, and in the mixing chamber between 0.3 and 30.
The method as claimed in 1, wherein the Particle-Froude-Number in the annular fluidized bed is between 0.115 and 1.15, in particular about 0.28.
Dependencies are inferred from the claim text.