Recycling waste incineration fly ash to prepare foam glass as building insulation material

Abstract

In this study, waste incineration fly ash and waste glass were used as the main raw materials for sintering to prepare foam glass, which has good application prospects as building insulation materials. The effects of different Na₂CO₃ additions and sintering atmospheres on the physical properties, microstructure and heavy metal leaching rate of the foam glass were investigated. It was shown that the best overall performance of the sintered foam glass was obtained when air sintering atmosphere and the maximum sintering temperature were 993 ℃, the fly ash content was 48 wt%, the waste glass powder content was 35 wt%, the Na₂CO₃ content was 5 wt% and the Na₂B₄O₇·10H₂O content was 12 wt%. Its water absorption is 5.7%, bulk density is 1.615 g/mL, alkali resistance is 99.3%, acid resistance is 97.6%, compressive strength is 9.52 MPa, thermal conductivity is 0.6653 W/mK, and its heavy metal leaching toxicity test is much lower than China’s national standard “hazardous waste identification standard leaching toxicity identification” (GB 5085.3-2007). It fully complies with the industry standard of foam glass. Therefore, the use of waste incineration fly ash and waste glass to prepare foam glass is an effective way to achieve efficient waste recycling and reduce the cost of construction material products.