Circular economy for municipal solid waste: A systematic review on resource management, recycling, and recovery

Municipal solid waste management (MSWM) is a central urban sustainability challenge, particularly in lower-income contexts where increasing waste volumes coincide with limited infrastructure, environmental pressures, public health risks, and social constraints. Yet municipal solid waste (MSW) is also a resource stream. Through thermal, hydrothermal, and biological treatment, MSW can be converted into energy, nutrients, and value-added materials while reducing greenhouse gas (GHG) emissions and diverting waste from landfills. Resource recovery and recycling extend the function of MSWM beyond collection and disposal, enabling materials, energy, and nutrients to be recaptured in line with circular economy (CE) principles and the sustainable development goals (SDGs). However, selecting suitable treatment options remains difficult because assessments often apply inconsistent criteria and insufficiently account for feedstock variability, local management conditions, and environmental, economic, and social trade-offs. This review synthesizes global advances in MSW-to-resource technologies and develops an integrated comparison of thermal, hydrothermal, and biological processes. The assessment links process suitability and technology readiness with MSW characteristics, economic viability, environmental impact, air pollution risks, and social acceptance. Advanced thermal processes can achieve electricity recovery of 544–816 kWh per tonne of MSW and reduce waste mass by 80–90%. Biological processes may offer stronger economic and environmental benefits, higher community acceptance, and greater technology readiness where organic waste streams are suitable. Together, these findings identify source segregation, revenue generation, public-private partnerships, public awareness and education, and carbon capture and storage as key enablers for aligning MSWM technology choices with CE objectives and local implementation conditions.