Evaluating and ranking suppliers in sustainable supply chain by WASPAS technique

The main goal of this research is to evaluate the key factors of sustainable supply chain management and ranking of suppliers by combining the factor analysis approach, SWARA and WASPAS.

the method of this research is description-measurement in terms of purpose, function and data collection. The statistical population for the research regarding the evaluation of the influence of factors with the factor analysis test includes approximately 300 experts, managers and experts of the country's gas industry in the field of related issues and involved in the planning, quality assurance, logistics and supply chain units of the gas industry, which in the end is a sample of 190 people taken into consideration.

The output of factor analysis showed that all factors are effective in implementing the system. In the following, using the opinions of 30 experts and using the new technique of SWARA, the aforementioned factors, were evaluated and the weight of the factors was extracted. The output of this technique showed that the fourth factor, "Education of company sustainability to managers" with the highest weight, is more important than other factors. In addition, the seventh factor (implementation of environmental management systems) ranks next in terms of importance in managing the sustainable supply chain of the country's gas industry. The sixth (activities to inform the society about sustainability) and the eighth factors (lawful legal procedures of favorable trade) are equally less important than other factors with the lowest weight. Finally, in order to realize the final goal of the research, the new WASPAS technique was used to rank the five sustainable suppliers of the industry and the ranking of the suppliers was extracted in terms of sustainability factors. The final output of the WASPAS technique showed that the fifth supplier ranked first, the first supplier ranked second, the second supplier ranked third, and the third and fourth suppliers ranked fourth with the same score.

The findings of this research provide a suitable view to domestic industry managers in the successful implementation of sustainable supply chain management. In addition, it can provide practical guidance to companies to implement sustainable supply chain management and, by providing a theoretical basis, encouraging the government in formulating sustainable development industrial policies.