Improving the energy efficiency in buildings while reducing the waste using autoclaved aerated concrete made from power industry waste

Production of autoclaved aerated concrete (AAC) from power industry waste cinders represents a progressive technology for processing of industrial waste in a new form of building material with good qualities. Despite these positive aspects, the share of cinder concrete in the building industry is less popular. The low popularity is partially caused by the poor aesthetic of cinder concrete in comparison with sand-based AAC; however, the main cause is the slightly smaller thermal and moisture qualities of fly ash-based AAC, respecting uncertainty because there are no supporting scientific research and publications about it. This paper is dedicated to a study of the thermal and moisture properties of the cinder concrete and mutual behaviour with the sand-based AAC. It was determined that fly ash-based AAC demonstrated slightly larger moisture sorption in comparison with sand-based concrete under similar conditions. On the contrary, the thermal insulating properties of fly ash-based concrete, as indicated by the heat conductivity, exhibits less moisture influence in comparison with sand-based AAC. Concerning volume changes, fly ash-based AAC showed, in the condition of low moisture, slightly better properties when compared with autoclaved aerated sand concrete.

► Energy use in the residential sector can be reduced if AAC walls are used.
► Energy saving while reducing the waste is possible with using fly-ash base AAC.
► The low popularity of fly-ash AAC is caused by uncertainty about its hygrothermal behaviour.
► The thermal and moisture qualities of fly-ash AAC and comparison with sand-based AAC were studied.
► Hygrothermal properties of fly-ash AAC are totally comparable to sand-based AAC.