2.Prepare regenerated magnesia carbon brick.
Baosteel takes the waste magnesia-carbon brick of ladle slag line as raw material, after sorting, removing surface inclusions, slag and oxide layer, adding 3%~4% thermosetting phenolic resin to mix, hydraulically pressing at 200 Celsius and 260MPa and curing for 5h, the regenerated magnesia-carbon brick is made, and the effect is similar to that of using new magnesia-carbon brick. After sorting, removing impurities, crushing, hydrating, drying and secondary crushing, the waste MgO-C bricks were treated with special purification technology to obtain excellent magnesia aggregate. The density, anti-spalling, oxidation resistance and corrosion resistance of regenerated magnesia-carbon bricks made from this raw material are equivalent to those of new bricks. The content of fused magnesia is selectively increased by purification treatment technology, so that it can be used as a high value-added raw material in practical production.
3. Prepare tundish dry materials.
The main raw material of magnesia dry vibration material in tundish is fused magnesia. In recent years, with the change of market demand, its price has far exceeded the cost, which makes the production of magnesia dry vibration material basically have no economic benefits. This situation promotes the development of the technology of preparing tundish dry materials from recycled magnesium-carbon materials. Guangzhou Iron and Steel Co., Ltd. and Maanshan Iron and Steel Co., Ltd. The preparation of recycled tundish dry materials with waste magnesia-carbon bricks instead of medium-grade magnesia was studied in Guangzhou Iron and Steel Company. Waste MgO-C brick particles are used to partially replace the middle-grade sintered magnesia in the original composition, and the properties are tested after being made into strips. It is found that both shaped and unshaped waste MgO-C brick particles can be used for tundish dry materials, and the comprehensive properties are better when shaped particles are used.
4. Prepare ladle gunning material.
According to the experimental results, the more recycled raw materials are added, the higher the porosity and lower the strength of gunning materials. Therefore, the added amount of recycled raw materials in field test is set at 20%. Hot gunning test was carried out in ladle of Steelmaking Plant of Meigang. The research shows that the regenerated gunning material has good gunning attach rate, dense coating and fast curing speed, which indicates that the regenerated gunning material can replace the existing gunning material.