對於不同種類染料之脫色而言,在目前各種廢水處理法中並無任何簡便,有效又能降低成本的適當方法。因此,本文研擬採用過氧化氫-亞鐵離子(Fenton's Reagent, F.R.)之氧化還原系統進行各種染料染色廢水之脫色處理,其中過氧化氫亦爲染色前處理常用助課劑,故期此法能獲得良好的脫色效果並降低廢水處理成本。
本文首先就實驗室配製五種主要應用染料之模擬染色廢水,然後以上述之FR氧化還原系統進行脫色試驗並探討其最佳脫色條件和脫色效果。最後,再實際染整工廠染色廢水之脫色試驗評估其實用性。由各項實驗結果顯示:過氧化氫-亞鐵離子氧化還原系統有極佳的脫色效果,即其最佳脫色效果之pH值範圍在pH1-3.5,過氧化氫與硫酸亞鐵之有效用量分別是584ppm與250ppm,而其有效用量會隨染色助劑含量增加而提高。溫度主要影響其脫色速率,低溫下其脫色處理時間較長,反之則可加速其脫色。另外,實驗室模擬染色廢水之脫色效果與實際工廠染色廢水者相當吻合。亦即經處理後的染色廢水其透視度均在25公分以上,COD去除率平均可達94%且COD值均在250以下,以及脫色率平均更可達97%以上。這些結果均已符合染整工業廢水放流水標凖(COD值250以下,透視度15公分以上)。
Five types of simulated dye wastewater, separately prepared with disperse, reactive, direct, acid and basic dyes, are decolorized in this article with a hydrogen peroxide-ferrous ion redox system, known as Fenton's Reagent. The results are that the best pH of decolorizetion is all lower than 3.5, the average rate of removing chemical oxygen demand (COD) is about 90% and the transparency of wastewater s all above 25 cm and the average decolorization rate is above 97%, And all results of treating the dye wastewater of mills are similar with those in lab. Temperature mainly influences the speed of decolorization, i.e. the lower the temperature, the longer the time for decolorization.