Sustainability assessment of municipal biowaste nutrient recovery under data scarcity: an integrated decision-support framework.

Sustainability assessment of municipal biowaste treatment pathways for nutrient recovery is often hindered by limited and uncertain data. Existing studies provide valuable evidence on individual treatment processes, but knowledge remains fragmented across technologies and sustainability dimensions, making cross-pathway comparison difficult. This study aims to comparatively assess municipal biowaste nutrient recovery pathways under data-scarce conditions by developing an integrated decision-support framework. In the first phase, a systematic literature review (SLR) was conducted to identify representative recovery scenarios and develop a multi-dimensional sustainability criteria system from a life-cycle perspective. In the second phase, a fuzzy multi-criteria decision-making framework was developed and applied to determine criteria weights and rank the alternative pathways under limited and uncertain data conditions based on expert judgment. Five municipal biowaste treatment scenarios were evaluated by integrating quantitative life-cycle-based evidence with expert judgment. The results identified in-vessel composter (IVC) as the highest-ranked pathway, followed by acid-assisted hydrothermal carbonization (HTC). More importantly, the study demonstrates that municipal biowaste nutrient recovery pathways can be comparatively evaluated and prioritized even when complete local datasets are unavailable. The proposed framework provides a structured basis for feasibility-oriented and context-sensitive decision support by jointly considering social, economic, environmental, and technical criteria.