- 期刊
含銅污泥資源化處理與實廠化可行性之評估研究
The Economic Evaluation of Resource Recycling Technology and Pilot Plant for Copper-Contaminated Sludge Treatment
摘要
本處理程序係將含銅污泥與鹼性溶液在攪拌或加熱曝氣攪拌之操作條件下，以單一浸漬步驟或重複浸漬程序提高含銅污泥中鋁成分的溶出量，經鹼浸漬處理後進行固液分離，藉由逆向流操作提高水溶液鋁離子濃度，使得鋁溶出率為49～87%，而污泥中的銅成份則累積在浸漬殘渣，使得殘渣中的銅回收率為73～93%。含銅污泥經過鹼浸漬處理後可以使污泥達到減量效果，污泥減重率為24～58%，同時銅成分被濃縮在過濾殘渣中。由於浸漬殘渣之乾基銅含量6～44%，不但符合銅冶煉精礦要求，可做為煉銅原料販售，而且節省有害污泥委託清除處理費用。而鹼浸漬處理之浸漬液含有濃度甚高之氫氧化鈉及鋁離子，能做為中和劑及混凝劑再使用，大幅減少處理藥劑費用，且處理後符合放流水排放標準。現今電鍍工廠每年花費於廢水處理費用約97.6萬元，若採用上述鹼浸漬資源化處理，不但不需付費，還能因販售氧化銅每年獲得3.1萬元利潤。而北部某一工業區之聯合污水廠目前每年處理費用高達2,318萬元，若改採加熱曝氣式資源化處理，除了可以舒緩污泥堆置的壓力外，每年尚可獲得142.4萬元之氧化銅產品利潤。初步估算若在電鍍工廠內設置一套1噸資源化設備，考量設備費用、操作維護費用、資源化產品產值與節省委託處理費用等因子，試算投資設備回收時期約僅需約2年後即可回收成本。相較於在聯合污水廠若設置一套6噸資源化設備，其投資設備回收時期僅需半年後即可回收成本，創造業者更大商機。
並列摘要
The purpose of this treatment process was to provide the method which could be utilized to recover copper and coagulant from copper-contaminated sludge by alkaline leaching. Alkaline reagent was used to mix with the sludge, and the leaching and stirring steps were followed and the temperature was controlled at 700C. When the reaction was completed, the pH value maintained stable and the solid-liquid separation was carried out. The filtrated residue was leached again by the same conditions until the dissolution percentage of Al from the sludge samples was about 49~87% and the Cu content was about 73~93% to be maintained in the residue solids. The weight losses of these sludge samples should be between 24% and 58%. By this treatment method, not only the waste reduction of copper-contaminated sludge can be achieved, but also the copper can be recovered from the sludge for the pyrometallurgic treatment. Owing to the great amount of alkaline and coagulant reagents exit in the leachate, it can be reused as neutralizer and coagulant in wastewater treatment to reduce the treatment cost. Nowadays, the costs of wastewater treatment in the electroplating plant and united wastewater treatment plant were 9.76X10^5 NT$/Year and 2.318 X10^7 NT$/Year respectively. If the both plants adopt the alkaline leaching process, the cost of wastewater treatment could be decreased greatly. The preliminary economic evaluation of the treatment capacity of I ton/day in the electroplating plant was discussed for copper-containing sludge which treated by alkaline leaching process. These cost parameters such as construction, operating and maintenance were considered. Therefore, the total investment which was utilized in alkaline leaching process could be returned in 24 months. However, the preliminary economic evaluation of the treatment capacity of 6 tons/day in united wastewater treatment plant was discussed which treated by alkaline leaching process. The profit of leached residue (i.e., copper oxide) could be calculated and the value is about 1.23X106 NT$/Year. Therefore, the total investment which was utilized in alkaline leaching process could be paid back time of 6 months.