目前世界各國正致力於「節能減碳」政策之推動與執行，行政院在政策白皮書亦宣示2025回到2008年二氧化碳排放量之目標。根據過往研究，廢棄混凝土回收再利用，已被證明足以節省材料及能源，以此觀點評估，理應有減碳之效益，如今國內廢棄混凝土再利用技術逐漸成熟，卻尚未針對廢棄混凝土不同再利用方式建立起二氧化碳評估模式，使得再利用減碳效益無法以量化數據評估，在總體二氧化碳減量目標下未能納入其貢獻，甚為可惜。 本研究依產品碳足跡計算精神，以生命週期觀點(Life cycle perspective)，評估產品從原物料取得，經能源與物料生產、製造，而至生命最終處置時，各階段二氧化碳排放量。國際間目前尚未建立混凝土產品類別規則(Product Category Rule, PCR)，使得產品系統邊界設定與計算範疇尚未確立，本研究參考國外計算案例，配合實地訪查及專家訪談下，確認混凝土產品評估時應納入之項目，並建立起再利用評估模式，用以評估廢棄混凝土不同再利用方式之減碳效益。 廢棄混凝土再利用方式種類繁多，本研究選擇高壓磚、CLSM、骨材為評估產品，調查其再利用製造流程，並蒐集各工廠間生產耗能數據，依功能單位強度下之配比，計算出產品碳排放量，再針對各單元碳排放量，探討其影響因素，提出具減碳成效之建議。 Countries around the world are advocating “energy conservation and carbon reduction” programmes. According to previous research, waste concrete recycling, saves material and conserves energy, it aids carbon reduction. This study is based on the carbon footprint guidelines to assess the product’s life-cycle of carbon dioxide emissions in each stage. There are no International rules in the concrete product category yet, so the system boundary and calculation of the product categories is not established. This study through the research methods, and establish a recycling model to assess the recycling of waste concrete in different ways to reduce carbon emissions. Three products evaluated in this study were high-pressure brick, CLSM, aggregate. This study investigated the recycling - product of the manufacturing process, and collect plant data to calculate the carbon emission products. The study based on these data to explore factors affecting carbon dioxide emissions. Finally, the study provides the proposed method of reducing carbon dioxide.
