Concept and Practice of High Performance Lightweight Castables
1 High Temperature Materials Institute, Henan University of Science and Technology, Luoyang, Henan 471003/China
2 Henan Gengsheng Refractories Co., Ltd., Gongyi, Henan 451271/China
Volume 6, Issue 2, Pages 63 - 74
Technologies and materials leading to reduced energy and material consumptions are receiving more attention and more importance given for the “low carbon era”. Lightweight (LW) castables are an important part of monolithic refractories, and realizing their high performance is very necessary to enhance the role of refractories in energy saving and reducing material consumption under tough working conditions. Concepts for high performance are put forward, summarized as “4-highs and 2-lows”, i.e. high purity, high strength, high service temperature and high resistance to the attack by furnace atmosphere, and low thermal conductivity and low shrinkage at service temperature. Different approaches to such requirements are introduced. Adopting the approaches and using high purity natural or industrial starting materials, LW aggregates in Al2O3–SiO2, MgO–SiO2 and Al2O3–CaO–MgO systems were prepared, featured by hollow sphere or micropore structure. They were used as aggregates to make LW castables in the corresponding system respectively. The developed high strength LW Al2O3–SiO2 castables have been adopted as steel ladle back lining, water cooled skid and post lining of reheating furnace and back lining of tin bath hearth in the glass industry, with very encouraging results. Laboratory work and in-plant trail indicate that the suggested approaches are effective.
lightweight aggregate, lightweight castable, monolithic refractories
Göller Verlag GmbH