In this study, we suggested an optimal strategy to sort plastic waste to improve recycling efficiency considering economic feasibility. To derive the optimal sorting strategy, we developed a novel optimization model that considers the overall cost, which is sorting cost minus the revenue obtained by selling the recycling plastic from the sorting cost. Then we used the developed model to identify the optimal strategy to sort plastic waste in mixed-integer programming that minimizes the overall cost of plastic waste sorting systems. We also conducted a sensitivity analysis to analyze the extent to which the results obtained can change under different conditions. The optimization results, identify that the plastics in the optimal sorting strategy are of four types: LDPE, HDPE, PP, and PVC. This optimal sorting strategy increase the overall sorting efficiency slightly by 4 wt%, but considering the revenue obtained by selling the recycled plastic the strategy significantly decreased the overall sorting cost by 69.28 % compared to the conventional case. The developed model can determine the optimal strategy to sort plastic waste considering economic improvement. Therefore, the results allow increase in plastic recycling by minimizing the overall cost of the sorting system.

在这项研究中，我们提出了一种对塑料废物进行分类以提高回收效率的最佳策略，同时考虑到经济可行性。为了推导出最佳分拣策略，我们开发了一种新的优化模型，该模型考虑了总成本，即分拣成本减去分拣成本中销售回收塑料所获得的收入。然后，我们使用开发的模型来确定在混合整数规划中对塑料废物进行分类的最佳策略，从而最大限度地降低塑料废物分类系统的总成本。我们还进行了敏感性分析，以分析所得结果在不同条件下的变化程度。优化结果表明，最优分选策略中的塑料有四种类型：LDPE、HDPE、PP 和 PVC。这种优化的分拣策略将整体分拣效率略微提高了 4 wt%，但考虑到通过销售回收塑料获得的收入，该策略与传统案例相比，整体分拣成本显着降低了 69.28%。所开发的模型可以确定考虑经济改善的塑料废物分类的最佳策略。因此，结果可以通过最小化分拣系统的总成本来增加塑料回收。