The Effect of Milled Municipal Solid Waste Incineration Bottom Ash on Cement Hydration and Mortar Properties

Abstract

Large amounts of municipal solid waste incineration bottom ash (MSWI BA) are formed worldwide, and this quantity is growing because of the establishment of new waste-to-energy plants. This waste is generally kept in landfills but can be used for the manufacturing of cementitious building materials. This article analyzes the use of MSWI BA as a microfiller in cement mortars. The effects of MSWI BA on the properties of cement binder and mortar were analyzed by using them separately or in combination with other microfillers: milled quartz sand, metakaolin, milled glass, and microsilica. This article investigates the flowability of cement-based mixtures, the volume change as a result of the evolution of hydrogen gas, cement hydration, XRD, TG, the physical and mechanical properties of the mortar samples, and leaching. The addition of milled MSWI BA in cement mortars was found to significantly increase slump flow; therefore, MSWI BA can be used as a microfiller. The addition of metakaolin changed the kinetics of H2, which evolved due to the reaction between Al and alkali, and had a positive effect on the mechanical properties of cement mortar.

Preparation and Hydration Properties of Sodium Silicate-Activated Municipal Solid Waste Incineration Bottom Ash Composite Ground-Granulated Blast Furnace Slag Cementitious Materials

“…MSWIBA is characterized by an unstable source, complex composition, nonuniform particle size distribution, and low reactivity, so it is necessary to adopt an activation treatment method to address the difficulties and problems of MSWIBA in engineering utilization [13]. Numerous scholars have explored the effect of MSWIBA at different blending levels on cement mortar or cement and found that bottom slag reduces the slump value [5,[13][14][15][16][17][18][19][20][21]. In contrast, the opposite trend was observed when used as a cement substitute.…”