People pay more and more attention to the recycling and reuse of refractory materials. If refractory materials can be fully and effectively used, it will not only reduce the mining of refractory minerals, reduce the production of refractory raw materials, but also save costs and energy consumption during the preparation process. The transportation cost of refractory raw materials is conducive to resource saving, energy saving and environmental protection.

　　1. Refractory materials can be recycled and used abroad

　　Foreign developed countries attach great importance to the reuse of refractories after use. They understand from the perspective of resources and environmental protection, and even formulate laws and regulations to strictly limit the emissions of refractories after use, which greatly promotes the research on the reuse of refractories after use. , The reuse rate of refractory materials after use has reached more than 60%, and it is continuously improving.

　　A Japanese steel plant uses waste bricks as the main raw material to develop ramming materials around the bottom of the ladle, ladle castables, and shaped products, such as: 85% recycled materials and 15% new materials are used to produce the electric furnace molten pool without burning Magnesia bricks, 90% recycled materials and 10% new materials are used to produce magnesia carbon bricks for electric furnace slag lines, and RH bottom-fired magnesia-chrome bricks are produced from all recycled materials. Kurosaki Company developed immersion nozzle bricks using waste corundum graphite products as raw materials. Kashima Iron and Steel Co., Ltd. has developed the secondary utilization technology of skateboard bricks. The repaired skateboard achieves the same use effect as the new skateboard by using surface polishing, castable casting restoration method, and ring inlay method; Repeated use, mainly used as aggregate of A12O3-SiC-C castable.

　　Italy OfficineMeccanichediPon-zanoVenetto company has developed a recycled post-refractory technology, which is mainly used to recycle various kilns, tundishes, ingot molds and ladle lining refractories, and directly inject the recycled refractories into the furnace , To protect the furnace wall. The United States used to recycle only a small amount of discarded refractory materials, and almost all of the rest was buried. In 1998, the U.S. Department of Energy, the Department of Industry and Technology, and steel producers jointly formulated a three-year plan to extend the service life of refractory materials and recycle waste refractory materials. Government support, cooperation between enterprises and research institutions have strengthened the research on refractory materials after use. The applicable scope mainly includes: desulfurization agent, slag modifier (slag forming agent), slag splashing furnace protection additive, calcium aluminate cement Raw materials, refractory concrete aggregates, paving materials, ceramic raw materials, glass industry raw materials, granular materials for roof construction, abrasives, soil modifiers. The cooperation between the refractory plant and the user minimizes the amount of waste refractory materials. The United States has also conducted research on the use of dolomite bricks as a soil conditioner and slagging agent, and good results have been achieved.

　　India’s earliest research on waste refractory materials can be traced back to 1978. It was first carried out in a steel pipe company, using the waste high alumina bricks (60%~62%) produced by the heating furnace of the Indian Steel Pipe Company (now TISCO Steel Pipe Branch). Alumina) produces castables (56% alumina), fire mud (50% alumina) and refractory plastics. The pouring materials developed are mainly used to produce burner bricks, dampers, tiles, etc., and can meet the internal requirements of the industry.

　　2. Domestic overview of the recycling and utilization of refractory materials

　　The research on the reuse of refractories after use in my country started late, and the reuse rate is relatively low. According to related reports, the recycling rate of refractories after use in my country is about 20%, and even the part that is used is at the cost of lowering the quality of the product. In recent years, major domestic steel plants and most refractory material plants have attached great importance to the recovery and reuse of refractory materials after use, and have continuously carried out research and application work in various aspects.

　　Baosteel's post-use refractory recycling work is going well. The blast furnace main ditch castables have been fully recycled and used as raw materials for slag ditch castables. The recycled magnesia-carbon bricks prepared after the used magnesia-carbon bricks have been regenerated and have antioxidant properties The advantages of strong slag resistance and long service life.

　　WISCO sorts the used aluminum-magnesium-carbon residual bricks and removes impurities, manually removes the sticky slag layer and transition layer, and conducts magnetic separation and hydration treatment. The materials are crushed to less than 25mm with a jaw crusher, and finally a hammer is used. The crusher is processed into the required particle size to prepare recycled aluminum-magnesium-carbon bricks.

　　Jinan Iron and Steel uses aluminum-carbon refractory materials (disused skateboard bricks, seat bricks, nozzles, and stoppers after use) as iron ditch ramming materials to replace some of the high-aluminum materials. The used magnesia-chrome bricks are used as raw materials and added to the RH gunning material in a certain proportion, and the effect is good. At the same time, the prepared recycled magnesia-chrome bricks have better performance and have better application prospects in non-critical parts of cement kilns and RH.

　　At present, domestic scientific researchers have also proposed: by adding appropriate amount of beneficial oxides to the refractory after use, improving and optimizing high-temperature performance, and preparing high-quality modified materials; preparing transformation materials through high-temperature reduction reactions, such as SiC, -Sialon, Maglon, etc. ;Use used clay bricks and used slide bricks to synthesize mullite; use used silica bricks and use C as reducing agent to synthesize SiC; use rear slide bricks to synthesize -Sialon; use rear slide bricks and used magnesia carbon bricks Synthesize Maglon and other oxide and non-oxide composite materials, so that the product has excellent performance such as high strength, thermal shock resistance and corrosion resistance, as a new type of high-efficiency refractory material for the key parts of high-temperature equipment, so as to realize the effective use of resources and energy.

　　The recyclability of refractories has become the current development trend of the refractory industry. If you want to make a breakthrough in the refractory industry, you must develop with the needs of society.