Long-term performance: strength and metal encapsulation in alkali-activated iron ore tailings.

Understanding the strength behavior and leaching characteristics of mining tailings stabilized with alkali-activated cements in the short, medium, and long term is crucial for the feasibility of material applications. In this context, this study assessed the stabilization/solidification of iron ore tailings (IOT) using alkali-activated binder (AAB) composed of sugarcane bagasse ash and eggshell lime at curing times of 7, 28, 60, 90, 180, and 365 days. Additionally, leaching tests were conducted, along with the examination of possible changes in the chemical and mineralogical composition resulting from exposure to acidic environments.

Technological characterization and environment-friendly possibilities to reuse water treatment sludge in building materials.

Water treatment plants (WTPs) produce thousands of tons of sludge annually, which is destined for landfill disposal, an environmentally and economically impractical alternative. Chemical, mineralogical, and morphological characterization besides environmental classification has been performed for WTP sludge and it was evaluated application potential in building materials, from a literature review. The characterization was carried out by X-ray fluorescence spectrometry, X-ray diffraction, scanning electron microscopy analysis, and leaching and solubilization tests.

Paint booth waste as an alternative aggregate for the production of interlocking concrete blocks.

Inadequate disposal of hazardous waste results risks to the environment and human health. Although the use of hazardous waste in new processes and/or products has received limited attention in the literature, there is still significant potential to be investigated. Reducing the usage of natural resources and waste management are important for sustainable practices during concrete production.

Metal encapsulation of waste foundry sand stabilized with alkali-activated binder: Batch and column leaching tests.

Waste stabilization processes are important to add value and reduce environmental risks related to metal contamination of soils and groundwater. This study evaluated the metal encapsulation of: (i) waste foundry sand (WFS) stabilized with an alkali-activated binder (AAB), compared to (ii) WFS-Portland cement (PC) mixture. The AAB was composed by sugar cane bagasse ash (SCBA), hydrated eggshell lime, and sodium hydroxide solution.

Mechanical and microstructural properties of iron mining tailings stabilized with alkali-activated binder produced from agro-industrial wastes.

This study evaluated the stabilization of iron ore tailings (IOTs) with an alkali-activated binder (AAB) produced from sugar cane bagasse ash, hydrated eggshell lime, and sodium hydroxide solution. Unconfined compressive strength, split tensile strength, initial shear stiffness, mineralogy, chemical composition, and microstructure of IOTs-AAB were evaluated. Strength values up to 6.

Experimental investigation of binder based on rice husk ash and eggshell lime on soil stabilization under acidic attack.

This study evaluates the use of rice husk ash (RHA)-eggshell lime (ESL) and RHA-commercial lime (CL) as alternative binders for clayey soil stabilization, as well as the performance of soil-binder mixtures under acidic attack. A central composite design was carried out to analyze the reactivity by batch tests with a sulfuric acid solution. Physical and mechanical behavior was evaluated by compaction test and unconfined compressive strength (UCS).

Leaching assessment of cemented bauxite tailings through wetting and drying cycles of durability test.

Disposal of mine tailings can cause negative environmental effects by releasing contaminants to surface and underground water. Alkali activation is a promising technique for immobilizing metals in stabilization/solidification of these wastes. This study evaluates the leaching behavior of cemented bauxite tailings (BT) submitted to weathering conditions.