Multi-objective production programming to systematic sorting and remanufacturing in second-hand clothing recycling industry

Abstract

This study proposes a multi-objective production programming model which is established for systematic sorting and remanufacturing second-hand clothes and the objectives are twofold: (1) minimizing the remanufacturing cost to maintain the competitiveness of second-hand clothing industry and (2) maximizing the recycle rate to reduce the environmental impact from the disposed clothes. Previous studies are lacking to involve the features of second-hand clothing recycled from reuse to recycle in optimizing both the remanufacturing costs and recycle rate. The consequential final destination of consumers' second-hand clothes is either resold, donated, or disposed of. This study applied sensitivity analysis by varying production cost and new material cost are conducted to evaluate the suitability of three different types of sorting methods for second-hand clothes before let them entering the remanufacturing processes on (1) categories the used clothes; (2) worn-out conditions (high, medium, low), and (3) clothes materials (cotton, linen, wool, silk, artificial fiber). The results show that the first sorting method by clothing categories outperforms the other two methods in maximizing the recycling rate. The second sorting method by worn-out condition generates a minimal remanufacturing cost. The recycling scenarios are simulated to verify the applicability of the proposed programming model with respect to the three sorting methods. The results show that Taiwan exhibited superior the recycle rates and Bangladesh had lower remanufacturing costs by adopting the sorting method by clothes materials.