煤渣資源回收再利用之成本效益分析

Economical Estimation of Reusing of Cinder

以燃燒煤碳取得必要的熱能仍是大部份傳統產業重要的能源來源，但燃燒後之煤渣及飛灰是否能適當的處理，乃業者是否繼續使用的重要因素，而若能將此煤渣及飛灰資源化，不但可節省大筆的廢棄物委托處理費，亦可因資源化產品，如植草磚，而增加額外收入，一舉數得。本文即以燃燒煤碳所產生之煤渣回收再利用、製成植草磚銷售，評估其成本效益；評估成本則以人、機、材及回收方法四種變因，即操作的人工費用、生產設備、材料（水泥）及原料準備，為基準。首先，先確定預定生產之產品在市場是否具備競爭力，即耐壓強度足夠與否及價格是否具競爭力，前者以調整配方、後者則以新購機器及改變原料進貨方式因應。接著，配合節省能源供應成本之公司策略，以垃圾衍生燃料取代部分煤碳，減少購煤成本，重新評估含取代燃料的煤渣再資源化之成本效益；此段成本效益之評估，是以產業獲得相同熱能的條件下進行，然後再依廢棄物委託處理或回收再利用、產品銷售利用、環保、法規及企業形象等多角度考量，評估損益狀況。結果指出，只燃燒煤碳之煤渣回收再利用而製成之植草磚，具市場競爭優勢；惟，如採用替代性燃料取代部分煤碳，雖可節省能源成本，但因所產生的煤渣回收製成植草磚之強度及品質，均無法與市場現有產品競爭，回歸廢棄物委托處理之計算，總實質的效益下降。

It is the major source of energy for the most traditional factory by burning coal. However, the important factor is weather the Cinder and ash are able to be treated well for continuing to use coal as the source of energy. If the Cinder and fly ash can be recycled and utilized, then, it will not only save the treat fee of waste, but also can sell the product of recycle materials, like bricks for plant. In this work, the economical estimation of recycling of Cinder to product bricks was done. The four estimating factors of labor, machine, materials, and method were used to calculate the cost. The first work was to decide the kind of product which has the competition, i.e. impact strength and reasonable price. The impact strength can be adjusted by the prescriptions. And, the reasonable price can be changed by buying new machine and changing the cement purchase. Next, the coal was replaced with the reused derived fuel （RDF） as the source of thermal energy. Because the price of RDF is cheaper than the coal under the same heat obtained. The cost structure of fuel and efficiency for RDF used was necessary to re-estimated. There are the treatment of waste, the price and utility of reused product, the environmental and legal factors, and the image of enterprise during the estimation. The results pointed that the reuse of waste Cinder is feasible. However, the replacement of thermal energy source can save some money, but the new coal tar cannot be reused as the materials of brick again. And, the company will pay more money to treat the waste because the environmental rule.