Porous materials produced from incineration ash using thermal plasma technology

Area of Science:

• Materials Science
• Environmental Engineering
• Waste Management

Background:

• Municipal Solid Waste Incinerator (MSWI) ash poses a disposal challenge.
• Traditional disposal methods can lead to environmental concerns.
• Recycling MSWI ash into valuable materials is highly desirable.

Purpose of the Study:

• To develop a novel thermal plasma melting technique for neutralizing and recycling MSWI ash.
• To investigate the conversion of MSWI ash into water-quenched vitrified slag.
• To explore the use of this slag as a raw material for producing porous building materials.

Main Methods:

• Plasma vitrification was employed to convert MSWI ash into water-quenched vitrified slag.
• Porous materials were fabricated using the vitrified slag, Portland cement, and a foaming agent.
• Properties such as density, porosity, water absorption, thermal conductivity, and flexural strength were evaluated.

Main Results:

• The plasma vitrification process yielded environmentally benign, water-quenched vitrified slag.
• Porous materials exhibited a bulk density of 0.9-1.2 g cm⁻³ and porosity of 50-60% with a closed-cell pore structure.
• The resulting porous materials demonstrated a low thermal conductivity of 0.1946 W m⁻¹ K⁻¹.

Conclusions:

• The developed technique effectively neutralizes and recycles MSWI ash into a valuable resource.
• The slag-based porous materials are lightweight, possess good thermal insulation properties, and are suitable for architectural applications.
• This approach offers a sustainable solution for MSWI ash disposal and promotes resource circularity in the construction industry.