| 摘要: | 本研究以ABS製程廢水為實驗對象，採用鋁鹽、三氯化鐵為混凝劑進行處理，實驗結果發現，兩種混凝劑對COD去除率只有9%（鋁鹽）與16%（三氯化鐵），可見廢水中含有大量的COD物質無法以混凝去除。探討原廢水之COD成份分佈，顯示廢水中能通過薄膜孔徑為10K之成份佔總COD之69%，足見廢水中含有大量小分子之有機物。添加粉狀活性碳實驗結果顯示，粉狀活性碳與混凝劑同時進行混凝時，COD去除率可提升至58%~61%。粉狀活性碳對石化廢水之吸附作用符合Freundlich等溫吸附模式理論。在混凝過程中添加粉狀活性碳，可明顯提升COD去除率，但對濁度的去除改善並不顯著，且添加之活性碳劑量越高，混凝沉降後上澄液濁度值越高。固定性固體物實驗 顯示，上澄液之高濁度值乃由過剩之粉狀活性碳所造成。本研究顯示COD的去除率與粉狀活性碳加入時間無關。當粉狀活性碳為低劑量添加時，濁度的去除率與粉狀活性碳加入時間無關，但當粉狀活性碳的添加劑量提升至25mg/L時，粉狀活性碳越晚加入，濁度之去除效果越差。
The application of powder activated carbon (PAC) for the enhancement of coagulation of nitrogen-containing industrial wastewater was studied. The sample got from a petroleum-chemical plant with a high TKN/COD value about 0.2, and 3500 mg/L in terms of COD, was available in this study. A jar test apparatus was used for the experiment followed by COD, turbidity, and fixed solid detects. There were two phases of this study, the first goal of this res t dosage of alum and FeCl3, respectively. The results showed the optimal operating pH of both coagulants for COD removal was with the almost same range from pH 6-8. For turbidity removal, alum was with a wide range from pH 6-11. However, it is independent on operating pH of FeCl3 for the removal of turbidity from pH 3-13. In general, the efficiency of turbidity removed by FeCl3 was higher than alum, but for COD, the reverse result was obtained. In addition, the optimal dosage for the removal of whatever COD or turbidity, less amount of alum was used than FeCl3. The further membrane analysis showed that there is 69% COD composed of the smaller molecular less than 10K. Furthermore, the adsorption of batch
experiments for raw wastewater by PAC fitted to Freundlich equation. The results showed the addition of PAC during the operation of coagulation could enhance the removal of COD, but it was not significant for the removal of turbidity for both coagulants. The results also indicated that the higher amount of PAC, the higher turbidity data was found in the supernatant after earch was to estimate the efficiencies of coagulation and determine the optimal pH and coagulan settling. The FS tests showed that the high turbidity was caused by the excessive PAC in the supernatant. The results of this study also showed that the removal of COD was independent on the addition timing of PAC during coagulation. This phenomenon could also be observed at low dosage of PAC (1mg/L and 10mg/L). On the other hand, at high dosage of PAC (25mg/L), the turbidity removal efficiency decreased with increasing the addition duration of PAC. |
