CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China; College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
Chemosphere. 2021 May;271:129810. doi: 10.1016/j.chemosphere.2021.129810. Epub 2021 Jan 30.
In this study, the organic matter in an O-based advanced oxidation process (AOP) for treating raw leachate (RL) and bio-treated leachate (BTL) was characterized. The optimal conditions for COD removal in RL and BTL treatment were as follows: initial pH of 6.0 and HO dosage of 9 mL 30% HO L leachate, and initial pH of 12 without HO addition, respectively. HO addition had little influence on COD removal in the BTL treatment as sufficient hydroxyl radicals may not be produced at extremely high pH levels. The differences in the alkalinity between RL and BTL caused differences in the optimum pH of the AOPs. Overall, the initial pH more affected COD removal than the HO dosage. O-based AOP converted organics with high molecular weight fractions into low ones. Meanwhile, it preferentially degraded hydrophobic substances over hydrophilic substances. The organic matter in the BTL contained more refractory and hydrophobic fractions; therefore, higher COD removal was achieved in the treatment of RL. The organics in the treatment of RL and BTL were identified by excitation-emission matrix spectroscopy combined with parallel factor analysis, and their degradation decreased in the following order: terrestrial humic-like > microbial humic-like > combination of tryptophan and humic-like components. O-based AOP significantly enhanced biodegradability. According to the economic analysis results, as an intermediate treatment, O-based AOP is a cost-effective strategy of ensuring that leachate effluent meets the discharge standards, with the lowest operating cost of $4.62 m. This study provides a reference for the application of O-based AOP in full-scale landfill leachate treatment.
在本研究中，考察了 O3 基高级氧化工艺（AOP）处理原渗滤液（RL）和生物处理渗滤液（BTL）中的有机物。RL 和 BTL 处理中 COD 去除的最佳条件如下：RL 初始 pH 为 6.0，HO 投加量为 9 mL 30%HO L 渗滤液；BTL 初始 pH 为 12，不添加 HO。HO 的添加对 BTL 中 COD 去除的影响较小，因为在极高的 pH 水平下可能不会产生足够的羟基自由基。RL 和 BTL 之间的碱度差异导致 AOP 的最佳 pH 不同。总体而言，初始 pH 比 HO 投加量对 COD 去除的影响更大。O3 基 AOP 将高分子量的有机物转化为低分子量的有机物。同时，它优先降解疏水性物质而不是亲水性物质。BTL 中的有机物含有更多的难降解和疏水性物质，因此在 RL 的处理中实现了更高的 COD 去除率。通过激发-发射矩阵光谱法结合平行因子分析鉴定了 RL 和 BTL 处理中的有机物，其降解顺序为：类腐殖质物质>微生物类腐殖质物质>色氨酸和腐殖质物质的组合。O3 基 AOP 显著提高了可生化性。根据经济分析结果，O3 基 AOP 作为一种中间处理技术，是确保渗滤液出水达到排放标准的一种经济有效的策略，运行成本最低，为 4.62 美元/m。本研究为 O3 基 AOP 在全规模垃圾填埋场渗滤液处理中的应用提供了参考。
