Complex BOF Slag Cut-Off System Using Developed Functional Devices Produced by GIR-Engineering LLC
DOI:
https://doi.org/10.15407/steelcast2024.03-04.002Keywords:
BOF, slag, primary cut-off system, secondary cut-off system, stopper, applicatorAbstract
One of the most essential tasks that must be solved in a modern BOF shop is to reduce the amount of final slag that enters the ladle during the tapping.
According to estimates from various researchers and practical experience, the amount of slag entering the ladle during the tapping is distributed as follows: up to 25% - at the beginning, up to 60% - at the end of the tapping and up to 15% - when the converter returns to its working position.
Today, there are two basic schemes for cutting off converter slag: automatic («active») and «passive». The primary automatic schemes include a «gas-dynamic» сut-off system and a «slide gate» type system. An affordable and effective alternative is the scheme of a “passive” primary and secondary BOF slag cut-off system using functional refractory devices.
The industrial facilities of GIR-Engineering LLC and PTIMA NAS of Ukraine have developed a "passive" scheme for the complex BOF slag cut-off system. It includes two systems: a primary cut-off with a plastic «tampon» type stopper and a secondary cut-off with the refractory «ball» / «dart» type stopper. Both systems work with manual applicators, which minimizes the capital costs of introducing them into the production chain.
During 2021-2024 years, at the PrJSC "KametStal" plant (Kamianske, Ukraine) (BOF with a capacity of 250 tons – 2 units.), successful industrial tests of the developed complex BOF slag cut-off system were carried out.
The total economic effect from implementation was ≈ 1.2 USD per ton of steel.
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