台灣地區稀土元素釹之物質流分析與資源管理

Abstract

稀土元素中的釹元素因具有特殊物化特性，目前廣泛應用在能源、通訊、電子和電器產品，是產品運作不可或缺的重要物質。然而，釹元素因產源掌控在少數國家且開採加工成本高，能開採使用的釹元素量有限，被許多國家列為戰略性稀有物質。臺灣之釹元素都依靠國外進口，若是未來供應出現短缺，勢必影響我國經濟產業與民眾生活，因此必須及早做好資源管理，將現有資源發揮最大效益，以減少對進口資源的依賴。 本研究之目的為藉由盤查台灣地區釹元素流量與流布，了解台灣對釹元素之使用情形，進而對釹元素提出資源管理策略，使其能達永續利用。研究方法以物質流分析量化台灣地區在2011年之釹元素流動與流布，再以物質流指標和情境分析法，計算2011年、未來相關綠能需求和回收情境之釹元素之物質流會計、資源使用效率和物質循環度，幫助提出適合的釹元素管理策略。 研究結果顯示2011年台灣地區釹元素之進口總量為5,859公噸，出口總量為3,783公噸，國內製造使用總量為5,632公噸，其中皆以電動機之流動量為最大佔比產品，分別佔79%、81%和79%，顯示電動機為目標年主要影響台灣地區釹元素進出口之產品項目。在國內含釹產品製造業方面，以機械設備製造業之釹元素資源生產力最高，能創造最大之單位釹元素附加價值。建議推行廢棄含釹產品之回收再利用，以產品之廢棄釹元素量大小建立回收優先順序，將回收之釹元素取代進口原料，並應用於資源生產力較高之產業。

Neodymium is a rare earth element with special physical and chemical properties, which is an essential material for energy, communication and electrical products. Because the sources of neodymium are dominated by only a few countries and usually take high cost on mining, the total amount of neodymium utilization is limited. Therefore, neodymium is regarded as strategic critical material by many countries. In Taiwan, resource of neodymium is relied on import. If there is a shortage of supply in the future, it will affect the economy and public life. In order to eliminate the dependence on the imported resources, we should manage the resource and optimize the benefit of existing resources. This study aims to investigate the usage conditions of neodymium in Taiwan by the inventory of its flow and distribution, and further propose the resource management strategy for neodymium to achieve sustainable utilization. The method of material flow analysis (MFA) is used to quantify the flow and distribution of neodymium in Taiwan 2011. The material flow indicators and scenario analysis are adopted to calculate the material flow accounts, resource productivity and circulation of neodymium of green energy demand as well as recovery scenario in 2011 and the future, contributing to propose the resource management strategy for neodymium. The result shows that total amount of imported neodymium is 5,859 tons, the exported neodymium is 3,783 tons and the domestic neodymium manufactured is 5,632 tons in 2011. The product motors dominates in all of the three product flows, as 79%, 81% and 79% respectively, presenting that motor is the main product affects the import and export of neodymium in Taiwan 2011. In the aspect of manufacturing neodymium in Taiwan, machinery and equipment manufacturing has the maximum resource productivity of neodymium, so it could create the largest adding value of neodymium per unit. This study suggests that according to the amount of neodymium in waste products, the priority of recycling could be decided to promote the reuse and recycling of the waste products containing neodymium. Then the recycling of neodymium will substitute parts of imported source and be applied to the industry which has higher productivity.