Coloured sintered glass-ceramics from hospital incineration fly ash

•The thermal plasma treatment for the hospital incineration fly ash utilization.•Chemical stabilization studies by leachability tests in raw materials and ceramics.•The physical features comparison of vitrificates in the hardness tests. The thermal plasma treatment is an effective method which can be used to convert hazardous waste into less toxic or inert glassy products. The aim of this paper is to show the experimental use of a thermal plasma treatment process to transform the hospital incineration fly ash into glassy products (vitrificates) that can be stored on the land without harmful environmental effects or sintered for producing with some additives coloured tiles useful as construction materials. The aims were achieved by: (i) optimization of temperature and energy used adjusting the process to minimum cost and (ii) stabilization of vitrificates with different compositions of waste mixtures. The chemical stabilization of final products was examined by heavy metals leachability tests. Hardness measurements were done to verify the physical stabilization of vitrificates. Also, it has been tested if the reinforcement and coloration of raw material by various pigments as well as the chemical compounds affect the stability of the final products. It was seen that chemical composition of raw materials influenced the chemical and physical properties of the vitrificates and decided about their internal structures.