ANALYSIS OF HEAVY METALS CONTAMINATION RISK OF BIOMASS ASH MADE OF CALCINED MUNICIPAL SEWAGE SLUDGE.

In a view of the sustainable development principles, the development of advanced lowcarbon building materials represents one of the most important issues in the construction industry. To follow the current trends in research and development of building materials, special attention is paid to the reuse of all kinds of waste and industrial byproducts. One of the serious problems of today's society is the huge production of sewage sludge from waste water treatment and its disposal. As one of the promising ways of sewage sludge disposal is incineration, there is a need to study biomass ash, its environmental hazards and further use in industrial applications. In this paper, the heavy metal contamination of biomass ash is analysed together with its chemical and phase composition, reactivity, microstructure and morphology. As the biomass ash was found to be pozzolana active, it was admixed to cement mortar, and the structural and mechanical parameters of this material were tested. The use of biomass had no negative effect on the properties of the cement mortar. Since the content of heavy metals in the biomass ash was safely below the valid limits, and the water-soluble salts were immobilised in the blended cement matrix, the biomass ash studied was classified among the alternative low-carbon pozzolans applicable in the development of eco- and energy-efficient construction products. [ABSTRACT FROM AUTHOR]