電路板剝膜廢液之化學及生物處理

Combined Chemical and Biological Treatment of Printed Circuit Board Wastewater

廖建治(Chien C. Liao)

指導教授 ： 林 勝 雄

元智大學/工程學院/化學工程與材料科學學系/碩士(2002年)

摘要

本實驗將原製程剝膜廢液先做酸化及化學混凝處理將存在於廢液中之大部分有機物質予以混凝沉澱，由pH值、PAC/polymer的加藥比來探討化學混凝法對廢液中有機物之化學混凝及脫色之效果;接著藉由批式實驗來探討電芬法處理剝膜廢液中難分解有機物，由pH值、電流密度、雙氧水加藥量、雙氧水不同加入方式來探討電芬法對製程剝膜廢中難分解有機物之電解氧化破壞及脫色的效果;最後，將電芬水混合一般生活廢水(3:1)，用回分活性污泥法進行最後處理，由pH值、混合比、污泥之MLSS探討處理效果，並以重複操作證明活性污泥可重複利用; 製程剝膜廢水經此階段處理，處理後COD去除率高達80 ％，可大量降低這股廢水的有機污染量，其COD可降至現行排放標準以下(120 ppm)，且其去色率在電芬法及化混處理後，已可達透明無色(ADMI值＜100)，因此，本研究針對難以處理之製程剝膜廢提供了一可行的途徑。

關鍵字

剝膜廢液 ； 化學混凝 ； 電芬法 ； 回分活性污泥法

並列摘要

Printed circuit board (PCB) manufacturing process consumes a large quantity of high-purity water for surface cleaning. The process thus produces a great volume of wastewater, containing various salts and many metal and organic pollutants. The wastewater, if not properly treated, can be detrimental to the environment.
The present study is to investigate treatment of PCB wastewater by combination of physical, chemical and biological methods, including chemical coagulation, electro-Fenton and sequencing batch reactor (SBR) method.
Chemical coagulation was adopted as a pretreatment of the raw PCB wastewater. The important operating variables of chemical coagulation included the initial pH, PAC/polymer ratio and the amount of PAC were examined and operating conditions identified for efficient operations. The test results have indicated that removal of suspended solids, color and some organic compounds by the pretreatment is quite good. After chemical coagulation, the wastewater effluent was treated by electro-Fenton in a batch reactor to investigate the effects of operating variables, including the initial pH, current density, the amount of hydrogen peroxide and hydrogen peroxide input method, on the oxidation performances . The results have shown that removal of color and some non-biodegradable organic compounds is excellent. Finally, sequencing batch reactor (SBR) method was considered as a polishing step for final treatment of the wastewater effluent. Various SBR test runs revealed that the SBR method was able to lower the final wastewater COD to below 120 mg/L and ADMI below 100.
In the kinetic studies, exponential, lumped and generalized kinetic models were adopted to model the electro-Fenton oxidation process. Best fit of these kinetic models was properly evaluated using the collected test data. The Eckenfelder kinetics of completely mixed type was adopted to model the biological reaction of the SBR process and the parameters of the model were empirically identified.

並列關鍵字

PCB wastewater ； chemical coagulation ； electro-Fenton ； sequencing batch reactor (SBR) method

參考文獻

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