以實驗設計法探討微波輔助過硫酸鹽氧化垃圾滲出水之最佳化研究

Optimization of Landfill Leachate Treatment by Microwave-assisted Persulfate Oxidation using Experimental Design Method

葉致榮(Chih-Jung Yeh)

指導教授 ： 駱尚廉

國立臺灣大學/工學院/環境工程學研究所/博士(2020年)

https://doi.org/10.6342/NTU202003809

摘要

臺灣的垃圾掩埋場滲出水，因色度、臭味及其處理技術、效果和成本等，而經常受到社會的關注。垃圾滲出水一般以物理及生物等處理方式均無法有效去除，本研究以非傳統式之高級氧化處理程序-微波(MW)技術，結合過硫酸鹽(PS)氧化劑進行滲出水處理。研究中探討三個實驗因子：MW功率設置、PS濃度及MW反應時間(T)，對三個目標參數：總有機碳(TOC)、色度及UV254處理效果之影響。另外，本研究首先利用田口(Taguchi)方法L16正交陣列(OA)設計，結合訊噪比(S/N)方法及變異數分析(ANOVA)，對微波氧化程序(MOP)進行滲出水處理實驗，探討各項操作參數對處理效果的影響；另外再以反應曲面方法(RSM)中的Box-Behnken (BBD)設計，進一步來達成最適實驗之設計及整體參數最佳化。
本研究在田口方法中求得最佳條件為：在550 W、20 mM及130 min時，TOC去除率為80%，色度去除率為96%；在775W、20 mM及130 min時，UV254去除率為55%。實驗因子的顯著性排名為：對於TOC的去除率，MW > PS > T；對於色度的去除率，PS > MW > T；對於UV254的去除率，MW > PS > T；可見在田口方法設計階段，MW之設置對MOP影響顯著。田口方法和ANOVA在最佳條件下預測的目標參數去除率與確認實驗所得之實際結果相似。接著摒除不顯著之水準，進一步的在RSM方法中進行二次迴歸模型建置，並使用ANOVA得出預測相關係數以及每個參數與測試參數之間的關係，其中等值線圖(2D)和反應曲面圖(3D)可顯示去除三個參數的最佳操作條件，而初始PS濃度對所有三個參數的去除影響最大。研究分析在個別的最佳操作條件下，TOC、色度及UV254的最高去除率分別為79.5%、100%及68.4%；而在整體最佳操作條件下，TOC、色度及UV254操作條件分別為447.7 W、20.0 mM及116.3 min，去除率分別為78.8%、100%及66.4%；在RSM設計階段PS則為顯著性因子。
田口方法應用在滲出水處理程序上，有容易及可快速找出最佳操作條件且較易理解之優點，但對中間反應過程變化較無描述；而反應曲面法針對處理之參數條件變化有較細微的分析，但相對理解或描述上略有難度，二者各有其優缺點。本研究結合此二種方法對微波加熱催化過硫酸鹽處理垃圾滲出水之處理程序加以探討，達成去除目標參數的目的。

關鍵字

垃圾滲出水 ； 微波氧化 ； 過硫酸鹽 ； 田口方法 ； 反應曲面法 ； 變異數分析

並列摘要

Landfill leachate issue in Taiwan was often to be concerned about for its treatment technology, effects, and costs. In this study, an experimental study using microwave oxidation process (MOP) to treat leachate was designed and optimized using Taguchi L16 orthogonal array (OA) design, coupled with the signal-to-noise (S/N) ratio method and the analysis of variance (ANOVA) method and compare the relationships in them. To go a step further, the experiment were optimized via response surface methodology (RSM) with a Box-Behnken design (BBD). Three experimental factors, microwave (MW) power settings, persulfate (PS) concetrations, and MW reaction time (T), as well as three target parameters, total organic carbon (TOC), color, and UV254, were studied.
In the Taguchi method, the optimal conditions were found to be: 550 W, 20 mM, and 130 min for TOC removals of 80% and color removals of 96%; 775W, 20 mM, and 130 min for UV254 removals of 55%. The ranking of significance of experimental factors were: MW > PS > T for TOC removals, PS > MW > T for color removals, and MW > PS > T for UV254 removals. The quality loss function values were used to compare the quality loss situation among different experimental conditions in the Taguchi OA design. The predicted removals of target parameters under the optimal conditions by Taguchi method and ANOVA were similar to the actual results from the confirmation experimental runs.
Further analysis in RSM design, the construction of second-order polynomial model, and ANOVA was used to derive the prediction correlation coefficient and the relationship of each factor on the test parameters. The contour-line plots and surface plots revealed the optimal operating conditions for removals of three parameters. The initial PS concentration had the most significant effect on the removals of all three parameters. The highest removals of 79.5%, 100%, and 68.4% for TOC, color, and UV254 attained under separate optimal operating conditions, respectively. The optimal operating conditions for TOC, color, and UV254 removals as a whole were derived to be 447.7 W, 20.0 mM, and 116.3 min with removals of 78.8%, 100%, and 66.4%, respectively.

並列關鍵字

Landfill leachate ； Microwave oxidation ； Persulfate ； Taguchi method ； RSM ； ANOVA

參考文獻

Abbas, A.A., Jingsong, G., Ping, L.Z, Ya, P.Y., Al-Rekabi, W.S., 2009. Review on landfill leachate treatment. Journal of Applied Sciences Research, 5, 534-545.

Abou-Gamra, Z.M., 2016. Kinetic and thermodynamic studies for oxidation of rosaniline hydrochloride dye by persulfate in ambient temperatures. Desalination and Water Treatment, 57, 8809-8814.

Al-Yaqout, A.F., Hamoda, M.F., 2003. Evaluation of landfill leachate in arid climate—a case study. Environment International, 29, 593-600.

Appleton, T.J., Colder, R.I., Kingman, S.W., Lowndes, I.S., Read, A.G., 2005. Microwave technology for energy-efficient processing of waste. Applied Energy, 81, 85-113.

Bashir, M.J., Aziz, H.A., Yusoff, M.S., 2011. New sequential treatment for mature landfill leachate by cationic/anionic and anionic/cationic processes: optimization and comparative study. Journal of Hazardous Materials, 186, 92–102.