Production of Portland cement clinker from French Municipal Solid Waste Incineration Bottom Ash

Abstract

The amount of bottom ashes generated from the municipal solid waste incineration is increasing considerably. Therefore their recycling is necessary in order to limit the landfilling that presents environmental issues. The aim of this paper is to recycle Municipal Solid Waste Incineration Bottom Ash from the north of France; as a secondary raw material for Portland cement clinker production. In this order Municipal Solid Waste Incineration Bottom Ash is characterized and then used to substitute raw materials for clinker production at laboratory scale. Substitutions rates up to 12.4 % have been tested. The produced clinkers have been characterized by X-Ray Diffraction and the crystalline phases were quantified by Rietveld analysis. The microstructure has been studied by scanning electronic microscopy. After adding gypsum, the compressive strengths of the corresponding cements were measured at 1, 7 and 28 days. The mineralogical composition of the 28 days hydrated cement pastes were studied by X-Ray Diffraction. The results show that up to 12.4 % of Portland cement raw materials can be replaced by the Municipal Solid Waste Incineration Bottom Ash without changing the mineralogical composition. In addition the compressive strengths of the cement pastes produced with Municipal Solid Waste Incineration Bottom Ash are equivalent to the one without bottom ash.