台灣主力科技種類為降低廢棄物處理與回收成本,出現事業廢棄物的清運與回收作業規劃問題,而多間工廠事業廢棄物縱使含有相同的有價回收物,但仍含有其他危險化學成分,以致回收中心無法同時回收多樣事業廢棄物,也衍生出在回收中心需決定一較佳的回收順序與回收時間分配,此部分為本研究之特色,而一般的回收處理產出型態中回收率為固定常數,但大部分印刷電路板與半導體等種類其回收率會隨著處理時間的增長而逐漸下降,故本研究設定回收率為非線性。根據以上環境限制,制定一套有效率的回收清運策略,探討應如何制定工廠與回收中心之間最佳清運週期,使雙方皆可在有效率的時間內得到最大利潤;以及探討如何使用回收策略於多工廠的廢棄物回收上有顯著的效益。 本研究的系統為多種類與單一回收中心,該系統下又分為單一種類來源為單一工廠與單一種類來源為多工廠,並分別建構整合式與分批式回收策略數學模型,並利用該模型透過程式撰寫來搜尋出不同目標下的最佳週期與目標。經實驗結果分析,無論工廠數量差異與工廠間規模大小差異,分批式回收策略均表現較好但在管理層面難度是較高的,且發現製程回收上限與製程回收率指數對回收中心而言,分批式策略影響效益較大。最後針對系統中影響非線性回收物收益的因子,工廠年總廢棄物數量、回收物定價、工廠數量及工廠間規模的差異進行敏感度分析,以提供企業經營管理參考之用。
High-tech companies in Taiwan face with the planning of disposal and recycling operations of industrial wastes to reduce related costs. There are various types of industrial waste that require services of recycling centers. The recycling center has to process batches of waste separately, even for those who are from the same industry. as a result, the sequence and time duration of batches of waste to be processed need to be carefully planned. Furthermore, in the process of recovering valuable materials from industrial waste, the recovering rate may drop as the processing time increases. Examples can be found in semiconductor and printed circuit board manufacturing industries. This research studies the planning of waste disposal and recycling operation in a green supply chain with multiple plants and multiple types of industrial waste. The goal is to identify optimal disposal cycles that minimize costs or maximize profits. This research considers systems with multiple manufacturing plants and a recycling center. Various types of waste can be from a single plant or many plants. Mathematical models are constructed under integrated recycling strategy and sequential recycling strategy. A search algorithm is developed to find the optimal disposal cycles. Numerical experiments and sensitivity analysis are conducted. We conclude that the sequential recycling strategy has better performance than the integrated recycling strategy, regardless the amounts of wastes and the size difference of plants. However, it requires more effort in management. The findings from this research can serve as valuable reference in management and operation for enterprises.