| Abstract [eng] |
In the master's thesis, slag and phosphogypsum waste were activated and analyzed using alkali activation process. These by-products were generated at the Lifosa AB plant and the Finnish metallurgical industry. Their compositions, physical properties, interactions during hydration and reusability were investigated. The purpose was to create a porous, high temperature resistant composite material that can be used in the construction sector as a sustainable insulating material. The aim of the research is to investigate a porous, alkali-activated composite material using aluminosilicate industrial by-products. The final work includes an analysis of the literature, which describes the relevance of alkali-activated materials, the principle of alkali activation process, the impact of high temperature to material, hardening and porosity-enhancing processes, and the applicability of materials. A research methodology is developed, which describes the research methods used in the master’s thesis, their expediency, and the logics of selection. The results of the research are discussed, and the interdependencies of the properties are determined. The results are described based on compositional studies of 5 different materials: compressive strength after 3-day hardening, compressive strength after 28-day hardening, air pore cross-sectional distribution, thermal conductivity properties, density, and compressive strength after the impact of 200, 400, 600 and 800 °C temperature. Based on the obtained results, the recommended content of phosphogypsum in the alkali-activated material is 3-5%, due to the optimal distribution of mechanical, thermal conductivity and high temperature resistance properties. |
