With increased population, treatment of solid waste landfill and its leachate is of major concern. Municipal landfill leachate shows variable, heterogeneous and incontrollable characteristics and contains wide range highly concentrated organic and inorganic compounds, in which hampers the application of a solo method in its treatment. Among different approaches, biological treatment can be used, however it is not effective enough to elimination all refractory organics, containing fulvic-like and humic-like substance. In this experimental study, the UV Electroperoxone process as a hybrid procedure has been employed to treat landfill leachate. The effect of various parameters such as pH, electrical current density, ozone concentration, and reaction time were optimized using central composite design (CCD). In the model fitting, the quadratic model with a P-Value less than 0.5 was suggested (< 0.0001). The R², R² adj, and R² pre were determined equal to 0.98,0.96, and 0.91 respectively. Based on the software prediction, the process can remove 83% of initial COD, in the optimum condition of pH = 5.6, ozone concentration of 29.1 mg/l. min, the current density of 74.7 mA/cm², and process time of 98.6 min. In the optimum condition, 55/33 mM H₂O₂ was generated through electrochemical mechanism. A combination of ozonation, photolysis and electrolysis mechanism in this hybrid process increases COD efficiency removal up 29 percent which is higher than the sum of separated mechanisms. Kinetic study also demonstrated that the UV-EPP process follows pseudo-first order kinetics (R² = 0.99). Based on our results, the UV-EPP process can be informed as an operative technique for treatment of old landfills leachates.

Graphical abstract

中文翻译：

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UV-Electroproxone工艺处理垃圾渗滤液的优化：能耗研究

随着人口的增加，固体废物填埋场及其渗滤液的处理成为主要关注的问题。市政垃圾填埋场渗滤液显示出可变，异质和不可控制的特征，并且包含范围广泛的高度浓缩的有机和无机化合物，这在其处理过程中不利于采用独奏法。在不同的方法中，可以使用生物处理，但是它还不足以消除含有难治性和腐殖质样物质的所有难处理有机物。在该实验研究中，采用紫外线电过氧化物处理工艺作为混合程序来处理垃圾渗滤液。使用中央复合设计（CCD）优化了各种参数（例如pH，电流密度，臭氧浓度和反应时间）的影响。在模型拟合中 建议使用P值小于0.5的二次模型（<0.0001）。R^{如图2所示}，确定R ² adj和R ² pre分别等于0.98、0.96和0.91。根据软件预测，在pH = 5.6，臭氧浓度为29.1 mg / l的最佳条件下，该工艺可以去除83％的初始COD。分钟，电流密度为74.7 mA / cm ²，处理时间为98.6分钟。在最佳条件下，通过电化学机理生成了55/33 mM H ₂ O ₂。在此混合过程中，臭氧化，光解和电解机理的结合使COD去除效率提高了29％，这高于分离机理的总和。动力学研究还表明，UV-EPP过程遵循伪一级动力学（R ² = 0.99）。根据我们的结果，可以将UV-EPP工艺作为一种处理旧垃圾填埋场渗滤液的有效技术。

图形概要