Bouchareb Raouf, Isik Zelal, Ozay Yasin, Karagunduz Ahmet, Keskinler Bulent, Dizge Nadir
Department of Environmental Engineering, Process Engineering Faculty, Saleh Boubnider University, Constantine, Algeria.
Department of Environmental Engineering, Mersin University, Mersin, Turkey.
Water Environ Res. 2022 Apr;94(4):e10717. doi: 10.1002/wer.10717.
In this study, a hybrid process for leachate wastewater treatment including evaporation and reverse osmosis (RO) membrane or biological treatment systems was suggested. Experiments were performed on a real landfill leachate wastewater. The leachate was subjected to evaporation; as a result, a distillate was obtained containing less organic matter and less substantial amounts of other pollutants, as ammonium salts and total phenols were removed. Tests were carried out at different evaporation temperatures and times. The initial leachate pH was adjusted and optimized. For optimum conditions, each of chemical oxygen demand (COD), total phenol, and ammonium salt concentrations were reduced to 99.99%, 95.00%, and 83.00%, respectively. The distillate of the first stage of the proposed process was then exposed to RO membrane system, as a first study, under different transmembrane pressure of 20, 30, and 40 bar and at different pH values of 7, 8, and 9. As a second suggested treatment system, the distillate was subjected to a biological treatment process for 30 days as a retention time, pH = 6, and room temperature 25°C ± 1°C. At the end of the research study, a comparison was conducted between results obtained with RO membrane separation and biological treatment system as two distinct treatment systems proposed for leachate landfill wastewater treatment. Although both systems were effective for landfill leachate wastewater treatment, however, with the RO membrane separation system, COD removal efficiency reached 99.99%. In the other hand, with biological treatment process, COD elimination was as much as 90.00%. Certainly, evaporation and RO are not novel ways of landfill leachate treatment; however, few studies have attempted to use similar combined system for landfill leachate wastewater treatment and attained effective results of treated water. PRACTITIONER POINTS: A hybrid process of evaporation and RO membrane or biological treatment systems was suggested for leachate wastewater treatment. For optimum conditions, COD, total phenols, and ammonium salt reductions were achieved to 99.99%, 95%, and 83%, respectively, after the first evaporation stage. The distillate of the first stage of the proposed process was then exposed to RO membrane system and biological treatment system. Different transmembrane pressure and different pH values were optimized for RO.
本研究提出了一种包括蒸发和反渗透（RO）膜或生物处理系统的渗滤液废水混合处理工艺。对实际垃圾填埋场渗滤液废水进行了实验。渗滤液经过蒸发处理；结果得到了一种馏出物，其有机物含量较低，其他污染物（如铵盐和总酚）的含量也大幅减少。在不同的蒸发温度和时间下进行了测试。对初始渗滤液的pH值进行了调整和优化。在最佳条件下，化学需氧量（COD）、总酚和铵盐浓度分别降低到了99.99%、95.00%和83.00%。然后，作为初步研究，将所提工艺第一阶段的馏出物在20、30和40巴的不同跨膜压力以及7、8和9的不同pH值下进行RO膜系统处理。作为第二个建议的处理系统，馏出物在pH值为6、室温25°C±1°C的条件下进行30天的生物处理，作为停留时间。在研究结束时，对作为渗滤液垃圾填埋场废水处理提出的两种不同处理系统（RO膜分离和生物处理系统）所获得的结果进行了比较。尽管两种系统对垃圾填埋场渗滤液废水处理都有效，然而，采用RO膜分离系统时，COD去除效率达到了99.99%。另一方面，采用生物处理工艺时，COD去除率高达90.00%。当然，蒸发和RO并不是垃圾填埋场渗滤液处理的新方法；然而，很少有研究尝试使用类似的组合系统处理垃圾填埋场渗滤液废水并取得了有效的处理水结果。从业者要点：提出了一种蒸发与RO膜或生物处理系统的混合工艺用于渗滤液废水处理。在最佳条件下，经过第一阶段蒸发后，COD、总酚和铵盐的去除率分别达到了99.99%、95%和83%。然后将所提工艺第一阶段的馏出物进行RO膜系统和生物处理系统处理。对RO系统的不同跨膜压力和不同pH值进行了优化。
