Preparation And Properties Of Red Mud-municipal Sludge Thermal Insulation Materials

Red mud is a by-product produced during the production of alumina from bauxite.Because of its high alkalinity and large output,long-term stacking will occupy a large amount of land,resulting in waste of land and human resources.The harmless treatment and effective utilization of urban sludge are also issues that all countries in the world attach importance to.Using red mud and urban sludge as raw materials to prepare building insulation materials is an effective way to effectively use red mud and urban sludge solid waste.It can not only reduce the accumulation of solid waste,but also recycle it.Research is not only of academic value.,Also has great environmental and social significance.This thesis uses red mud and municipal sludge as the main raw materials to prepare sintered thermal insulation materials and obtains the following research contents:(1)When only red mud and soot carbon powder are used as raw materials for sintering reaction,albite and anorthite phases with stronger thermal stability are formed.(2)When the ratio of red mud and municipal sludge is 6:4,6 wt% soot carbon powder is added to sintering at 1100? to achieve the best sintered sample water absorption rate of 2.8%,thermal conductivity 0.38 W/(m·K),The bulk density is 1.263 g/cm3,and the strength is 15.8MPa.It meets the national standard for green building materials and reaches the A-level insulation material.(3)Perform laboratory scale-up experiments on samples with the best ratio.Change the sintering temperature to solve the problem of cracking during the sintering process,and add aggregate alumina to reduce the thermal conductivity and increase the strength of the sample.(4)A magnified sample was carried out at China Nonferrous Metals Group Jinlu Refractory Co.,Ltd.,and a brick-shaped sample of 230 mm × 115 mm × 42 mm was obtained.The sample has a good appearance without obvious deformation,corner drop or bending.