Constructing and selecting optimal sustainable sanitation system based on expanded structured decision-making for global sanitation and resources crisis

Abstract

Facing with global sanitation and resources crisis, developing and identifying optimal sustainable sanitation system (SSS) is particularly challenging in most of global areas through conventional solution. A novel method by coupling macro-environmental content analysis, compatibility assessment, and multi-criteria decision analysis into structured decision-making is developed and applied to select the optimal SSS to improve the rural human settlements environment of Beijing, China. A predictive model of weighting coefficient has been proposed to deal with the interactions based on the data-driven method considering temporal (56-y time frame) and geographic (87 countries) factors. The technologies space with mature technologies of SSS came from 402 demonstration projects of the world. The results show that vacuum toilet + vacuum sewer + anaerobic digestion/composting (for blackwater) + struvite crystallization (for yellowwater), and biogas/composting toilet + gravity sewer + anaerobic digestion/composting is suitable for high and middle income Districts of Beijing, respectively, in the coming 5–10 years. Although the novel method is the first application in SSS planning, the proposed method can also be extended to apply to other complex infrastructure decision-making.