Combined use of MSWI bottom ash and fly ash as aggregate in concrete formulation: Environmental and mechanical considerations

Background: Municipal solid waste incineration (MSWI) bottom ash contains a not insignificant amount of metallic aluminum, while circulating fluidized bed combustion (CFBC) fly ash is rich in active SiO2. Objective: To reduce the materials cost of autoclaved aerated concrete (AAC) production, these two types of solid waste could theoretically be used as the aerating agent and silica source, respectively. Method: In the present work, the metallic aluminum concentration in an MSWI bottom ash sample was determined from hydrogen generation and this ash was used to make AAC in conjunction with CFBC fly ash. The extent of air entrainment in the resulting AAC specimens was varied by changing the bottom ash to fly ash ratio, and the effects of this ratio on the properties of the AAC were investigated. Results: Results showed that the ratio has a negligible effect on both the type and the morphology of the hydrates in the AAC, but is inversely proportional to the compressive strength, density and volume stability. Conclusion: This study proves that AAC having satisfactory properties can be successfully prepared from a combination of MSWI bottom ash and CFBC fly ash.

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Characterization of lead-bearing phases in municipal waste combustor fly ash

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100165045 ◽

1996 ◽

Vol 54 ◽

pp. 516-517

Author(s):

L. L. Sutter ◽

G. R. Dewey ◽

J. F. Sandell

Keyword(s):

Fly Ash ◽

Bottom Ash ◽

Municipal Waste ◽

Primary Concern ◽

Leaching Behavior ◽

Waste Combustion ◽

Lead And Cadmium ◽

Lead Speciation ◽

Accepted Practice

Municipal waste combustion typically involves both energy recovery as well as volume reduction of municipal solid waste prior to landfilling. However, due to environmental concerns, municipal waste combustion (MWC) has not been a widely accepted practice. A primary concern is the leaching behavior of MWC ash when it is stored in a landfill. The ash consists of a finely divided fly ash fraction (10% by volume) and a coarser bottom ash (90% by volume). Typically, MWC fly ash fails tests used to evaluate leaching behavior due to high amounts of soluble lead and cadmium species. The focus of this study was to identify specific lead bearing phases in MWC fly ash. Detailed information regarding lead speciation is necessary to completely understand the leaching behavior of MWC ash.

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Effect of Additive on the Rheological Characteristics of Slurries of Fly Ash and Bottom Ash Mixture at High Concentrations

International Journal of Fluid Mechanics Research ◽

10.1615/interjfluidmechres.v36.i6.50 ◽

2009 ◽

Vol 36 (6) ◽

pp. 538-551

Author(s):

Sunil Chandel ◽

S. N. Singh ◽

V. Seshadri

Keyword(s):

Fly Ash ◽

Bottom Ash ◽

Rheological Characteristics ◽

High Concentrations

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Ternary Mixes of Self-Compacting Concrete with Fly Ash and Municipal Solid Waste Incinerator Bottom Ash

Applied Sciences ◽

10.3390/app11010107 ◽

2020 ◽

Vol 11 (1) ◽

pp. 107

Author(s):

B. Simões ◽

P. R. da Silva ◽

R. V. Silva ◽

Y. Avila ◽

J. A. Forero

Keyword(s):

Fly Ash ◽

Municipal Solid Waste ◽

Solid Waste ◽

Bottom Ash ◽

Chloride Diffusion ◽

Waste Incinerator ◽

Chloride Diffusion Coefficient ◽

Municipal Solid Waste Incinerator ◽

Self Compacting Concrete ◽

Solid Waste Incinerator

This study aims to evaluate the potential of incorporating fly ash (FA) and municipal solid waste incinerator bottom ash (MIBA) as a partial substitute of cement in the production of self-compacting concrete mixes through an experimental campaign in which four replacement levels (i.e., 10% FA + 20% MIBA, 20% FA + 10% MIBA, 20% FA + 40% MIBA and 40% FA + 20% MIBA, apart from the reference concrete) were considered. Compressive and tensile strengths, Young’s modulus, ultra-sonic pulse velocity, shrinkage, water absorption by immersion, chloride diffusion coefficient and electrical resistivity were evaluated for all concrete mixes. The results showed a considerable decline in both mechanical and durability-related performances of self-compacting concrete with 60% of substitution by MIBA mainly due to the aluminium corrosion chemical reaction. However, workability properties were not significantly affected, exhibiting values similar to those of the control mix.

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