Blast Furnace Lining and Cooling Technology: Experiences at Corus Ijmuiden

摘要

The latest experiences at blast furnaces No. 6 and No. 7 of Corus IJmuiden prove the effectiveness of the plate-cooled lining and cooling concept selected in the early 1970s and improved and optimized over subsequent campaigns. This state-of-the-art design has now achieved a campaign length of 16 years without any interim repairs to the bosh, belly and stack. Due to the replacement of refractories for the bottom, hearth, tuyeres and lower bosh, BF No. 6 began a new, fifth campaign in June 2002. For the major bosh part, the belly and the stack, BF No. 6 has continued its 17th year of its fourth running campaign, with a productivity of 14,700 thm/m^ WV (12,810 thm/m~3 IV) as of the spring of 2002 for that bosh part, belly and stack. It is expected that a considerable number of years can be added to the campaign length of the bosh, belly and stack refractories, while the new bottom and hearth refractories are anticipated to achieve at least 16 years again. Blast furnace No. 7 had completed 11 years of its third running campaign at the time of this writing, and it was expected to achieve at least the same campaign length as BF No. 6. The lining and cooling system of the bosh and stack is very forgiving with respect to high heat loads and process deviations. The blast furnace can therefore reliably be driven to the unknown limits of production and PCI injection, which is exactly what the operators wish to achieve. Current productivity up to 3.0 thm/m~3 WV/24hrs and higher can be achieved at a constant hot metal quality with a traditional burden composition. In addition, coal injection rates of up to 230 kg/thm are accepted as standard practice. The longer campaign life is due not only to the integrated lining and cooling system design, but also to the investigations and long-term trials that have translated into operational procedures for high productivity at acceptable heat losses.