Sustainable Closed-Loop Mask Supply Chain Network Design Using Mathematical Modeling and a Fuzzy Multi-Objective Approach

The outbreak of the deadly coronavirus, which is increasing the number of victims every
day, has created many changes in today�s world. The use of various masks is the most important
social tool against this virus. Given the importance of rapid and quality supply of masks in the
current situation, it is necessary to study supply chain in particular. In this research, the design of
a closed chain supply chain network for different types of masks is assessed. The studied supply
chain includes suppliers, manufacturers, distributors, and retailers in the forward flow and collection
centers, separate centers, recycling centers, and disposal centers in the backward flow. In this regard,
a multi-objective mathematical model with the objectives of increasing the total profit and reducing
the total environmental impact, and maximizing social responsibility is presented. The optimization
of this mathematical model has been done using a fuzzy optimization approach in GAMS software.
The results of this study show that maximizing the total profit and minimizing the environmental
effects and maximizing social responsibility are in contrast to each other. In addition, the sensitivity
analysis indicated that the customers� demand can affect all aspects of the sustainable supply chain
simultaneously.