ARRANGEMENT AND METHOD FOR REDUCING BUILD-UP ON A ROASTING FURNACE GRATE

• Main Authors: SIIRILAE, KEIKKI, NYBERG, JENS, JAERVI, JUHA
• Format: Patent
• Language: English; French
• Published: 19.09.2002
• Edition: 7
• Subjects: AIR; BLASTING; CHEMISTRY; COMBUSTION APPARATUS; COMBUSTION PROCESSES; DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS,IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KINDOF FURNACE; FERROUS OR NON-FERROUS ALLOYS; FURNACES; FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; HEATING; KILNS; LIGHTING; MECHANICAL ENGINEERING; METALLURGY; METHODSOR APPARATUS FOR COMBUSTION USING FLUID FUELOR SOLID FUEL SUSPENDED IN; OPEN SINTERING OR LIKE APPARATUS; OVENS; PRETREATMENT OF RAW MATERIALS; PRODUCTION AND REFINING OF METALS; RETORTS; TREATMENT OF ALLOYS OR NON-FERROUS METALS; WEAPONS

The present invention relates to an arrangement and method that help to redu ce 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 f ed via gas jets under the grate in the bottom of the furnace in order to fluidi ze the concentrate and oxidize it during fluidization. Below the concentrate fe ed 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 fe ed grate higher than the other jets. The extra jets of the feed grate are connected to their own gas distribution unit.