Multi-layer high-strength thermal insulation ceramsite and preparation method thereof

The invention belongs to the technical field of solid waste resource utilization and high-strength thermal-insulation aggregate preparation, and particularly relates to a multi-layer high-strength thermal-insulation ceramsite and a preparation method thereof.The preparation method comprises the following steps that 1, molybdenum tailings, fly ash, sludge, steel slag and calcium carbonate are smashed, mixed, granulated and dried, and inner-layer pellets are obtained; (2) crushing molybdenum tailings, fly ash, sludge, steel slag and carbon powder, and adding water for mixing treatment to obtain middle-layer slurry; (3) the molybdenum tailings are smashed, water is added for treatment, and outer layer slurry is obtained; (4) wrapping the surface of the inner-layer material ball obtained in the step (1) with the middle-layer slurry obtained in the step (2), and drying to obtain a mixed material ball; and wrapping the surface of the mixed material ball with the outer layer slurry obtained in the step (3), and sint