BOF Product Management, RHI AG (Vienna, Austria):

Kollmann Th., e-mail: thomas.kollmann@rhi-ag.com
Jandl Ch.

A higher level of product sophistication and unstable charging material quality require an economically optimized basic oxygen furnace (BOF) process operation. Technological benchmarking to assess different operating philosophies (e. g. with bottom gas purging versus without bottom purging) as well as various maintenance approaches (e. g. slag maintenance and maintenance using unshaped refractory products) and their infl uences on process stability and achievable metallurgical results are discussed. BOF maintenance matrix including the investment cost, operator stress, and metallurgical influence is presented and analyzed. It is shown that technical maintenance of converters end expectations of metallurgical results of oxygen purging process can’t be considered separately, because no one of the current repair methods can provide the lowest level of consumption and the best metallurgical results. Today practice of usage of saturated MgO slags as a cheap refractory material holds expenses for lining repair at a low level with simultaneous origination of essential deficiencies in purging process and in ladle treatment. This problem can be solved using reasonable compromise adapting to the concrete requirements.

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