| 초록 |
Plastic waste is a mixture of different types of plastics, and thus it is difficult to recycle these materials because of their association with other incompatible type of plastic. However, due to the cost-intensive sorting process of plastic waste, only 27.2 wt% of plastic waste is recycled. This work, we optimized the plastic waste sorting system to increase recycling efficiency considering economic feasibility. To derive the optimal sorting strategy of plastic waste, a novel optimization model is developed and it determined the overall cost calculated by subtracting the profit of recycling plastic from the sorting cost. Then the proposed optimization model is used to identify the optimal sorting strategy of plastic waste in mixed-integer programming that minimizes the overall cost. As a results, in the derived optimal sorting strategy, the sorted plastics are four types of plastics (i.e., LDPE, HDPE, PP, and PVC). The overall sorting efficiency is slightly decreased by 3 wt% according to selective sorting. However, the overall cost considering the profit of plastic recycling is significantly increased by 92.5 % compared to the conventional case. |
