Arrangement and method for reducing build-up on a roasting furnace grate

摘要

The present invention relates to an arrangement and method that help to reduce the build-up formed on the grate of a fluidized-bed furnace in the roasting of fine-grained material such as concentrate. The concentrate is fed into the roaster furnace from the wall of the furnace, and oxygen-containing gas is fed via gas jets under the grate in the bottom of the furnace in order to fluidize the concentrate and oxidize it during fluidization. Below the concentrate feed point, or feed grate, the oxygen content of the gas to be fed is raised compared with gas fed elsewhere using additional gas jets situated in the feed grate higher than the other jets. The extra jets of the feed grate are connected to their own gas distribution unit.