Optimization of preparation process and performance analysis of fly ash foam glass

Abstract

Foam glass was prepared with fly ash and glass powder as main raw materials, sodium carbonate as foaming agent, and trisodium phosphate as suds-stabilizing agent. The influence of the amount of fly ash and sodium carbonate, foaming temperature and foaming time on the compressive strength, flexural strength, apparent density and thermal conductivity of foam glass was studied by orthogonal experiment and the optimum technological conditions for preparing foam glass were obtained. The pore structure, morphology, pore size distribution, morphology and crystal precipitation of foam glass were investigated by means of Occhio Scan v750, Nano Measurer, SEM and XRD. The result shows that the amount of fly ash has a significant influence on the mechanical and thermal conductivity of foam glass, the foaming temperature has the greatest influence on the apparent density, and the influence of sodium carbonate content on the average pore size is the most obvious. The pore numbers of 9 sets of samples are approximately normal distribution with the change of average pore sizes, and the average pore sizes of 0.1-2.0mm exceed 85%. There is a certain amount of crystal precipitating inside the foam glass and the major and secondary crystalline phase are nepheline and diopside respectively.