Comparative Evaluation of Municipal Solid Waste Treatment Technologies: A Comprehensive Review and Sustainability Assessment Using Analytic Hierarchy Process

Abstract

Rapid urbanization, increasing population density and changing consumption patterns have intensified municipal solid waste (MSW) generation, making sustainable treatment selection a complex multi-criteria decision problem. This study presents a comprehensive review and sustainability assessment of major MSW treatment technologies with emphasis on stream-wise treatment planning for urban local bodies. The review covers biological treatment, thermal conversion, recycling/material recovery and special urban waste streams, including vermicomposting, mechanical composting, bio-methanation, waste-to-energy, plastic recycling, construction and demolition waste processing, hazardous waste treatment, e-waste processing and biomedical waste management. The sustainability performance of treatment alternatives was evaluated using the Analytic Hierarchy Process (AHP) based on four criteria: initial cost, operation and maintenance cost, environmental positive impact and social impact. The criteria weights indicated that environmental positive impact received the highest importance, followed by operation and maintenance cost, social impact and initial cost. The consistency ratio of the AHP matrix was below the acceptable threshold of 0.10, confirming the logical consistency of the decision model. The AHP-based ranking showed that bio-methanation achieved the highest sustainability priority, followed by waste-to-energy and mechanical composting. Bio-methanation was found most suitable for segregated wet organic waste due to its energy recovery potential, digestate generation, landfill diversion and social benefits. Waste-to-energy was suitable only for dry combustible rejects or RDF after source segregation and material recovery. The study concludes that sustainable MSW management cannot be achieved through a single treatment technology. Instead, a stream-wise integrated treatment framework is required, where each waste fraction is matched with an appropriate technology based on waste characteristics, resource recovery potential, operational feasibility and environmental sustainability.