Utilization of Different Grain Size of Municipal Solid Waste Bottom Ash in High-Performance Mortars

Abstract

Globalization is bringing increased industrialization and municipal solid waste (MSW). This is a major concern in heavily populated areas. In order to reduce MSW generation, incineration is commonly used, resulting in two types of ashes: bottom and fly ash. Bottom ash is gathered at the incineration bed and is larger in mass than fly ash. To test the qualities of high-performance mortar, MSW-BA in three sizes (fine, medium, and coarse) was replaced with sand at three replacement levels of 10%, 20%, and 30%. The high-performance mortar integrating MSW-BA was tested for hardened density, mechanical properties such as compressive and flexural strength, resistance to NaOH solution, and heavy metal leaching. The substitution level of MSW-BA increased the hardened density of the mortar mixes. The volume change and residual strength of the mortar mixes were measured following exposure to the NaOH solution. Fine-particle mortar mixes shrank whereas medium-and coarse-particle mortar mixes expanded. The largest loss in flexural and compressive strength was recorded when 20% of sand was replaced with a fine fraction of MSW-BA. Heavy metals including cadmium and copper were not leached from MSW-BA combinations of any size. The minuscule amounts of lead and zinc discovered were well below acceptable limits. The present study illustrates the MSW-BA can be utilized as a substitute for sand in the development of high-performance mortar.