Process combination for mechanical co-processing of residues from municipal solid waste treatment

Area of Science:

• Waste Management
• Environmental Engineering
• Materials Science

Background:

• Municipal solid waste (MSW) management involves distinct thermal recovery (waste incineration - MSWI) and mechanical-biological treatment (MBT) methods.
• While valuable fractions from MBT are utilized in MSWI, their treatment residues are handled differently; MSWI slags undergo processing, but MBT residues are landfilled.
• A gap exists in connecting MBT residue treatment with established MSWI processing infrastructure.

Purpose of the Study:

• To develop a mechanical pre-treatment process for separating a usable stream from MBT rotting residues.
• To evaluate the suitability of this separated stream for processing using existing MSWI slag technologies.
• To establish a link between MBT and MSWI at the residue treatment level.

Main Methods:

• Development of a mechanical pre-treatment process to fractionate MBT rotting residues.
• Evaluation of the separated stream's compatibility with established MSWI slag processing techniques.
• Quantification of recovered materials (metals, glass, ceramics/stone) and generated feedstock (refuse-derived fuel, organic material).

Main Results:

• A partial stream from MBT residues was successfully separated and integrated into MSWI slag processing.
• Recovery rates include 1% metals, 7.9% glass, and 4.3% ceramics/stone.
• A 5% high-calorific refuse-derived fuel feedstock and 65.3% organic material (potential pyrolysis feedstock) were generated, reintegrating 28.4% of MBT residues into the material cycle.

Conclusions:

• Mechanical pre-treatment enables the reintegration of a significant portion of MBT rotting residues into the material cycle via existing MSWI infrastructure.
• This study establishes a novel connection between MSWI and MBT at the residue treatment level, promoting circular economy principles.
• The developed process offers a sustainable alternative to landfilling MBT residues, enhancing resource recovery.