印刷電路板顯影去墨廢液以Fenton法配合PAC吸附處理之研究

The study of Develop¬-Etch-Stip wastewater from Printed Circuit Board manufacture process treated by Fenton accompany with PAC adsorption

鄭永富(Yong-fu Cheng)

指導教授 ： 曾迪華

國立中央大學/工學院/環境工程研究所碩士在職專班/碩士(2008年)

摘要

印刷電路板業(Printed Circuit Board，PCB)的顯像、剝膜或去墨製程中，會排放出高濃度的有機廢液。傳統的處理方式，大多以酸化作為前處理，並介由其他低COD 濃度的廢水大量混合稀後，再進行後續處理，以期符合放流標準。近年PCB業由於積極配合政府節約用水政策，使得可用於稀釋顯影去墨廢液的水量減少，因而使得最終放流水COD值往往無法符合放流水標準。有鑑於此，本研究以某PCB廠的顯像、剝膜/去墨顯廢液為對象，評估以Fenton法配合PAC吸附作為後續處理程序，而使放流水可直接符合COD管制值(COD≦120mg/L)的可行性。
本研究首先分別探討Fenton及PAC操作參數對COD處理效能影響，並建立合適操作條件。主要內容係利用田口直交法分析影響Fenton程序的顯著因子，並以平衡及動力吸附試驗，評估PAC的吸附能力。最後再探討酸化前處理、Fenton法及PAC吸附之程序組合的處理成效。
研究結果顯示，影響 Fenton法去除顯影去墨廢液，COD之最顯著因子，為過氧化氫濃度，其次是亞鐵濃度。此兩者最適重量比(Fe2+/H2O2 )為0.7，其中當Fe2+=2100mg/L且H2O2=3000mg/L時，COD去除率較高 (約75%)。PAC的平衡吸附實驗，所顯示之曲線圖型屬第一型之單層吸附現象，對COD的吸附能力極高，去除率約在75%。PAC的動力試驗顯示，對COD的吸附速度極快，吸附5分鐘即可得到92%吸附量，經50分鐘可達吸附平衡。去墨顯影廢液酸化後,再以Fenton法與PAC吸附法各別進行處理時，在相同的COD去除率下，Fenton法成本將較PAC吸附法低。若顯影廢液經酸化處理後,再以Fenton與PAC進行組合處理時，發現以PAC+Fenton之組合對COD之去除效果最好， COD值可1800mg/L降至≦120mg/L之國家放流標準。

關鍵字

顯像、剝膜/去墨廢液 ； PAC ； Fenton ； 印刷電路板 ； 田口直交法

並列摘要

The develop-etch-strip (DES) process of the printed circuit board (PCB) essentially produced wastewater with high concentration of organic matter. The acids treatment was applied as a pre-treatment processes in many of the traditional treatment methods. In that, huge amount of the low COD wastewater was use to dilute the wastewater with high COD content in order to meet the regulation of the discarge. Recently, most PCB manufacturers reply save water policy of the government. However, it makes dilution water quantity decrease and the effluents of PCB processes become more difficult to meet the regulation standard of the discharged. In order to resolve the problems mentioned above, this study focused on the primary COD wastewater of PCB manufacturers, such as DES wastewater to treat by Fenton method combined with powder activated carbon (PAC) adsorption processes.. It was expect the COD of the treated wasdtewater can be under the current wastewater discharge standard of 120mg/L, and make more water resource reuse.
The research focused on the relationship among the parameters of Fenton, the PAC operation, and the COD reduction. Meanwhile, sets up an acceptable operation conditions. The obviously factors were analyzed by Taguchi orthogonal arrays. The adsorption ability of the PAC was evaluated by the equilibrium adsorption examination. The efficiency of the combination of acidic pre-treatment, Fenton, and PAC adsorption were then investigated.
The results shown that most of the important factors of COD reduction of develop-etch-strip wastewater is the concentration of hydrogen peroxide, the second one is the ferrous concentration. The optimum mass ratio (Fe2+/H2O2 ) is 0.7. When Fe2+ is 2100mg/L and H2O2 is 3000mg/L, the greater COD reduction (around 75%) was achieved. Concerning the PAC adsorption examination, the result demonstrate the mono-layer first type adsorption model, and 75% adsorption efficiency was obtained. The dynamic adsorption examination of PAC showed the COD adsorption with a related quite high speed. By 5-min adsorption with 92% adsorption quantity and achieve the equilibrium condition after 50-min. When treating acidized DES wastewater with Fenton and PAC adsorption, the running cost of Fenton is lower than PAC adsorption under the same COD reduction efficiency. While using the acidized DES wastewater treated combination with Fenton and PAC, the COD reduction efficiency of PAC plus Fenton is optimum one, and the COD could be reduced from 1800mg/L to less than 120mg/L of the National Effluent Standard.

並列關鍵字

Develrp-Etch-Strip ； PAC ； Fenton ； Printed Circuit Board ； Taguchi orthogonal arrays

參考文獻

4. 行政院環境保護署，環保法規，2008年4月。

溫吸附模式之建立」，國立中山大學環境工程研究所，碩士論

板協會2007年10年。

11. Fenton, H. J. H., J Chem. Soc., 65, pp. 899, 1894.

Future in Hazardous WasteTreatment”, Waste and