OPTIMIZATION MIXTURE RATIO PARAMETERS OF LIGHTWEIGHT AGGREGATES INCORPORATING MUNICIPAL SOLID WASTE INCINERATION FLY ASH AND ELECTROLYTIC MANGANESE RESIDUES USING THE UNIFORM DESIGN METHOD.

In response to the declining availability of natural resources to use as raw and construction materials, the use of waste materials partial or complete alternative of natural resources for the preparation of lightweight aggregate (LWA) has been a hot topic of research. This study investigated the possibility of using the municipal solid waste incineration (MSWI) fly ash, electrolytic manganese residues (EMR) and Coal fly ash as materials to prepare LWA by a high temperature sintering process. The uniform design (UD) method was employed to design the experiments of LWA, and a quadratic regression method was used to establish regression model for studying the mixture ratio of raw materials and the properties of LWA. The results indicated that the data were well fitted by the regressed second-order polynomial models, the interaction between the raw materials was investigated. Optimum the mixture ratio of raw materials to meet three response were obtained and verified, EMR was 49.19%, MSWI fly ash was 12.91% and Coal fly ash was 37.90%. The pellets were prepared according to this optimal recipe and calcined at 1140 °C for 13 min to meet light - aggregate of GB/T 17431.2 - 2010 standard. The heavy metal extraction values of LWA were all much lower than the standard described in "Identification standard of hazardous waste-identification of leaching toxicity (GB 5085.3 - 2007)" and the "landfill standard (GB 16889 - 2008)" achieving the dual purpose of detoxification and utilization of MSWI fly ash and EMR. [ABSTRACT FROM AUTHOR]