Tannery solid waste valorization for achieving SDGs: An innovative decision-making model for critical success factors analysis and sustainable technology selection

Sustainable tannery solid waste (TSW) management is essential for achieving several sustainable development goals (SDGs) and promoting carbon neutrality in the leather processing industry. However, the sustainable management of TSW in developing countries remains a relatively ambiguous and unexplored area in the research. To expedite the sustainable management of TSW, it is essential to conduct a comprehensive study of critical success factors (CSFs) and valorization technologies considering the uncertainties involved as TSWs are major contributors to environmental pollution and carbon emissions. Unfortunately, existing models are unable to effectively handle uncertainty on a broader scale when evaluating interdependencies and valorization technologies. Therefore, this study proposes a novel integrated model that combines Interval Type-2 Trapezoidal Fuzzy Sets (IT2TrFSs) based Delphi technique, an extended version of the Weighted Influence Non-linear Gauge System (WINGS) method, and IT2TrFSs- Combined Compromise Solution (CoCoSo). This model is then applied to assess the interdependencies among CSFs and TSW valorization technology using a real case study. The IT2TrFSs-WINGS analysis reveals that “Environmental policies for TSW management” is the most crucial causal CSF, with a value of 0.00560. The IT2TrFSs-CoCoSo analysis confirms that “Gasification” is the most promising TSW valorization technology, receiving a significant preference value of 2.03982. These findings will enable decision-makers, relevant stakeholders, and environmental agencies to take necessary actions towards improving the TSW management process in developing countries.