台灣通用塑膠物質流分析

Abstract

塑膠是現代社會中不可或缺的材料之一，低成本、易塑形、重量輕、不易產生反應等特性使其被大量的生產使用，卻也造成極大的廢棄物污染問題。各國針對塑膠聚合物提出許多的管理方法，其中大部分成效有限，主要原因是因為塑膠的種類及用途過於繁雜，管理策略難以了解塑膠使用的實際情況。因此本研究針對回收編號1-6號，世界上最廣泛使用及回收的六種通用塑膠：聚酯粒、高密度聚乙烯、聚氯乙烯、低密度聚乙烯、聚丙烯、聚苯乙烯進行研究，盤查政府機關、供應商及文獻的資料，再透過物質流分析方法（Material Flow Analysis），繪製通用塑膠桑基圖（Sankey Diagram），幫助提供塑膠管理的數據參考。 台灣110年生產的六類通用塑膠共9,437,017噸，塑膠種類以PET最多，占比高達43%。原料進口700,536噸，出口4,667,879噸。製造投入共5,484,214噸，假設5.07%的製造損失，1,475,161噸產品出口，剩餘3,704,764噸在台灣使用。使用的用途以包裝占比(35%)最高，其次是電機電子設備(19%)、紡織品(17%)、家用與其他(7%)、自動車(6%)、農業(3%)。預估當年度生產使用的塑膠會有1,606,952噸在同一年被廢棄，占使用的35%。廢棄物管理系統方面，110年共收集1,909,496噸的廢棄塑膠（包含非通用塑膠），分離的廢棄塑膠占比僅18.44%，皆來自於塑膠包裝或容器，其中還有一部分來自進口塑膠廢棄物。收集的廢棄塑膠有39.85%進入回收處理，剩餘50.11%進入焚化處理、3.28%進入掩埋處理、0.86%進入其他處理。利用塑膠包裝使用需求及回收的分離塑膠量計算包裝回收率及評估2025年25%再生塑膠包裝目標，結果顯示目前包裝的回收率約16%。回收的廢棄塑膠最大可提供約15%包裝需求的再生塑膠，需仰賴進口塑膠廢棄物才能達成2025年的目標。 由研究結果可以顯示台灣在一次性塑膠製品的大量使用，尤其是在包裝方面，且塑膠廢棄物的分離收集率低，可能造成再生塑膠的原料污染及產品品質不佳，進而導致再生塑膠的使用意願降低。

Plastic is an indispensable material in modern society due to its low cost, pliability, lightweight, and non-reactivity. However, these characteristics have also led to significant problems of plastic waste pollution. Many countries have implemented various management methods for plastic polymers, but their effectiveness has been limited mainly due to the complexity of plastic types and applications, making it difficult to understand the actual usage of plastic. Therefore, this study focuses on the six most widely used and recycled general plastic types: polyester (PET), high-density polyethylene (HDPE), polyvinyl chloride (PVC), low-density polyethylene (LDPE), polypropylene (PP), and polystyrene (PS). By examining data from government agencies, suppliers, and literature, this research utilizes Material Flow Analysis (MFA) and Sankey Diagrams, aiming to provide data references for plastic management. In Taiwan, a total of 9,437,017 metric tons of the six general plastic types were produced in 2021, with PET being the most prevalent, accounting for 43%. There were 700,536 metric tons of plastic material imports and 4,667,879 metric tons of exports. The total input for manufacturing was 5,484,214 metric tons, assuming 5.07% manufacturing losses and 1,475,161 metric tons of product exports, leaving 3,704,764 metric tons for domestic use in Taiwan. The major uses of plastic were packaging (35%), followed by electrical and electronic equipment (19%), textiles (17%), household and others (7%), automotive (6%), and agriculture (3%). It is estimated that 1,606,952 metric tons of plastic used in the same year would become waste, accounting for 35% of usage. In terms of waste management, a total of 1,909,496 metric tons of plastic waste (including non-general plastics) were collected in 2021. Only 18.44% of the collected plastic waste was sorted, and it mainly came from plastic packages or containers. Some of the collected plastic waste also originated from imported plastic waste. Of the collected plastic waste, 39.85% went for recycling, while 50.11% went for incineration, 3.28% for landfilling, and 0.86% for other treatments. By considering the demand for plastic packaging usage and the amount of separated plastic waste for recycling, the packaging recycling rate was calculated to be approximately 16%, and it was evaluated that achieving the 25% target of recycled plastic packaging by 2025 would require relying on imported plastic waste. The research findings indicate that Taiwan has a significant reliance on disposable plastic products, especially in packaging, and the separated collecting rate of plastic is low. This may lead to contamination of recycled plastic raw materials and poor product quality, resulting in a decreased willingness to use recycled plastic. The data results can provide a numerical foundation for further research and strategy development by management agencies.