Municipal Solid Waste Incineration Fly Ash: From Waste to Cement Manufacturing Resource

Abstract

This study investigates the possibility of using municipal solid waste incineration fly ash as a supplementary cementitious material to replace part of the clinker in cement. Life cycle assessment has shown that the partial replacement of clinker with blast furnace slag (CEM III) reduces cement’s global warming potential by ~30%, while replacing clinker with fly ash reduces it by up to 55%. When using CEM III as the control binder in cement in which 55 wt% of the clinker was replaced with hydrothermally treated fly ash, the flexural strength decreased by ~60% and the compressive strength by ~65%. When the fly ash was mixed with calcined and vitrified demolition materials, flexural strength decreased by ~30% and compressive strength by ~50%. The hardening of the hydraulic binders fixed the heavy metals in the municipal solid waste incineration fly ash.

Resistance and durability of fly ash based geopolymer for heavy metal immobilization: properties and mechanism

“… 5 Out of the various methods used in China for disposing of FA, the S/S technology is considered the most prominent. 6 S/S is a procedure that entails the amalgamation of a fixing agent with an immobilization agent, followed by a reaction conducted under precise conditions to generate a solidified matrix. The stabilization of FA primarily takes place through physicochemical processes, leading to the creation of a stable compound that has minimal toxicity and is highly resistant to migration or dissolution.…”

“…Additionally, the preparation of geopolymers eliminated the need for milling and calcination processes, resulting in carbon dioxide emissions reduction. 6 …”

Study of a Fire-Resistant Plate Containing Fly Ashes Generated from Municipal Waste Incinerator: Fire and Mechanical Characteristics and Environmental Life Cycle Assessment

“…MSWI-FAs can be directly used as a Portland cement replacement [9][10][11] but they are commonly used with other raw materials in cement-making rotary kilns [12]. Another issue with MSWI-FAs high chloride level is that it might lead to corrosion and blockages.…”