Blast furnace relining strategies for campaign lives of more than 20 years

摘要

Owing to the concentration of hot-metal production on a few large-capacity blast furnaces only, it is imperative to fully utilize all technical opportunities for extending the blast furnace campaigns. Complete or intermediate relinings cause longer shutdown periods. The resulting production shortfall cannot be compensated by means of standby furnaces; projected up to the finished product of an integrated iron and steel mill, considerable economic disadvantages arise. The design and the layout of blast furnaces together with the blast furnace operation are the most important criteria for the campaign life. The possibility to realise blast furnace campaigns with more than 20 years and without reduced productivity of the furnace during the total campaign go back to many years of experiences with blast furnace operation of ThyssenKrupp Stahl especially on the fields of: - optimisation of refractory construction and quality for the hearth and the shaft of the furnace in dependence on the installed cooling efficiency; - strategies for the long term operation of peripheral installations like cast houses, hot stoves and gas cleaning systems; - repair methods to prolong the campaign life of the blast furnace and all the components. This admittedly high level of the state of the art must, however, at the same time be regarded as a challenge for the future to expand the available know-how to ensure minimisation of the abrasive, thermal and chemical wear and as such to massively extend the service life of all units of an integrated blast furnace plant.