爐碴作為一貫化作業的副產品，伴隨著鋼鐵材料的製造大量產出，現行的處理技術與安定化流程卻不敷使用，導致大量的爐碴變成負資產，不當囤積汙染環境且浪費資源，本研究依循循環經濟的理念，將廢棄物轉為資源，希望能將爐碴重新投入產業鏈循環。本實驗使用脫硫爐碴，此為電弧爐後二次精煉調整304鋼種成分時的副產品，脫硫爐碴經粉末冶金程序，活化並形成穩固的多孔結構，作為濾除磷的材料，不僅可以使體積固定方便運輸，且在過濾過程中不須攪拌混和設備，不會阻塞儀器，其適當的孔洞率也能增加反應面積，平衡濾片的機械性質與濾水效率。
XRF分析顯示，還原碴主要組成元素為鈣與矽，兩者相加，占總成分的95 %以上，其中的鈣為用於濾磷的主要有效成分，占60 %以上。將XRD與SEM的結果相互對照時發現，爐碴經過1000℃熱處理後，將使得有助於濾磷的礦物成分，例如：白雲石，因高溫而變質，且有晶型的轉變，導致連通孔的減少。而800℃的熱處理溫度，不足以固化樣品，部分樣品無法通過萬能試驗機的壓縮測試，未符合ASTM C159 - 06(2016)的標準。900°C的最高熱處理溫度，在活化成分與調節pH值及機械性質都有最佳的表現，因粉末冶金的特性，由阿基米德法測定皆可得到28 vol%以上的孔隙率，經計算，5 wt% PVA 貢獻約8 vol%的孔隙率。
在除磷實驗中，鈣溶出量多與pH值高，均有助於除磷，其中，以pH值的影響較大。未添加造孔劑的濾片，為符合放流水標準且限制3小時濾水時間的情況下，可重複使用6次，有添加造孔劑的濾片則多至8次，其中，LF _900_ 10 在第8次濾水時，去磷率仍可高於99 %。使用磷酸二氫鉀與磷酸二氫銨調配高磷水，結果證明，爐碴在不同背景下的濾磷效能沒有顯著差異，為了完全符合標準，此種濾材使用壽命為6次以下。由於塊狀多孔爐碴的製作及使用過程與安定化相似，有希望在符合相關規範的情況下製成隔音牆等，使得濾後的爐碴塊得以繼續循環使用。

Waste utilization is an attractive alternative to disposal as disposal cost and potential pollution problems are reduced or even eliminated along with the achievement of resource conservation. Steelmaking operations are specifically concerned in this problem because of the generation of a huge quantity of by-products. Approximately 1.5 million furnace steel slag is produced each year in the Taiwan, thus to find out a suitable utility is needed. In this study, ladle furnace steel slag (LF slag) was modified to apply for the filtration of phosphorous-rich water and to save time and resources from other utilities. Powder metallurgy (PM) method was applied for materials processing to prepare a porous steel slag filtering element. Activating the slag prior to incorporation into wastewater treatment filters could remove the aging affect. It then results to higher pH value of the phosphorus-rich water (P-rich water) and the uptake of PO43-. When the effluent pH value fell below 9, the P removal percentage started to decrease significantly. The appropriate heating temperature and higher pH value are favorable for the uptake of PO43-. Lightweight block-forming porous ladle furnace steel slag with low densities, large specific surface, and high strength is expected to reduce transport cost and the frequency of replacement in the process of filtrating.

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