A novel inorganic thermal insulation material utilizing perlite tailings

Installing thermal insulation materials on the external and/or interior wall is a primary means for the conservation of building energy. Expanded perlite is one of the most widely used inorganic building insulation materials nowadays. However, it not only consumes a large amount of energy in the fabricated process, but also produces a great deal of perlite tailings during the exploiting or smashing process. In this work, a new kind of light foamy thermal insulation materials were prepared utilizing perlite tailings by an energy-saving and environment-friendly method. The influences of each raw materials, including perlite/sodium silicate, H2O2, cetyltrimethyl ammonium bromide and rock wool, on the physical properties (such as pores characters, thermal conductivity and mechanical strength) were discussed in detail based on the formation processes of the foamy thermal insulation materials. The optimized foamy materials showed low thermal conductivities (0.040–0.060 W·m−1·K−1) with low apparent densities (0.1–0.2 g cm−3) and relatively high mechanical strength (0.09–0.6 MPa). As compared with other reported inorganic thermal insulation materials, this new type of thermal insulation material was very light and exhibited much better heat-insulated performance. Therefore, this work not only proposed a new energy-saving method for obtaining a kind of promising non-flammability insulating materials, but also solved the problem of solid tailings utilization.