Abstract
This study introduces an integrated decision-making methodology to choose the best "waste-to-energy (WTE)" technology for "municipal solid waste (MSW)" treatment under the "interval-valued Pythagorean fuzzy sets (IPFSs)". In this line, first, a new similarity measure is developed for IPFSs. To show the utility of the developed similarity measure, a comparison is presented with some extant similarity measures. Next, a weighting procedure based on the presented similarity measures is proposed to obtain the criteria weight. Second, an integrated approach called the "interval-valued Pythagorean fuzzy-complex proportional assessment (IPF-COPRAS)" is introduced using the similarity measure, linear programming model and the "complex proportional assessment (COPRAS)" method. Furthermore, a case study of WTE technologies selection for MSW treatment is taken to illustrate the applicability and usefulness of the presented IPF-COPRAS method. The comparative study is made to show the strength and stability of the presented methodology. Based on the results, the most important criteria are "greenhouse gas (GHG)" emissions (P3), microbial inactivation efficacy (P7), air emissions avoidance (P9) and public acceptance (P10) with the weight/significance degrees of 0.200, 0.100, 0.100 and 0.100, respectively. The evaluation results show that the most appropriate WTE technology for MSW treatment is plasma arc gasification (H4) with a maximum utility degree of 0.717 followed by anaerobic digestion (H7) with a utility degree of 0.656 over various considered criteria, which will assist with reducing the amount of waste and GHG emissions and also minimize and maintain the costs of landfills.