School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, United States; Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China.
School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, United States.
Water Res. 2017 Oct 15;123:224-235. doi: 10.1016/j.watres.2017.06.073. Epub 2017 Jun 27.
The removal of precursors of 36 disinfection byproducts (DBPs) in effluents from flocculation/sedimentation process was evaluated across a pilot-scale two-stage biofiltration process, i.e., a sand/anthracite (SA) biofilter (empty bed contact time (EBCT) of 7.5 min) coupled with a biologically-active granular activated carbon (GAC) contactor (EBCT of 15 min). The biofiltration process exhibited a good capacity for removal of the total DBP formation potential (DBPFP) (by 25.90 ± 2.63%), and GAC contactors contributed most to the DBPFP removal (accounting for 60.63 ± 16.64% of the total removal). The removal percentage of DBPFPs of different structure types was in the following order: halonitroalkanes (58.50%) > haloaldehydes (33.62%) > haloacetic acids (HAAs, 28.13%) > haloalkanes (20.46%) > haloketones (13.46%) > nitrosamines (10.23%) > halonitriles (-8.82%) > haloalkenes (-9.84%). The precursors of bromo-DBPs (containing only bromine atoms) and maximal halogenated DBPs (containing 3 & 4 halo atoms) were removed largely compared to other DBPs. Among the total DBPFP, trihalomethanes (THMs), HAAs, and chloral hydrate were the dominant DBPs, and they accounted for >92% of the total targeted DBPs by weight. Pearson correlation analysis (CA) and principal components analysis (PCA) indicated a significant association among these dominant DBPs. Canonical correspondence analysis (CCA) revealed specific ultraviolet absorbance (SUVA) could serve as a good surrogate parameter for DBPFP. Pre-chlorination upstream of the biofilters may not greatly impact the overall removal of DBPFP by SA/GAC biofiltration. In addition, results showed that SA/GAC biofiltration was a useful procedure to remove the inorganic DBP chlorite.
采用中试规模两段生物过滤工艺（即砂/无烟煤（SA）生物滤池（空床接触时间（EBCT）为 7.5min）与生物活性颗粒活性炭（GAC）接触器（EBCT 为 15min）耦合）评估了在絮凝/沉淀工艺出水中去除 36 种消毒副产物（DBP）前体的效果。生物过滤工艺对总 DBP 形成潜力（DBPFP）的去除能力很强（去除率为 25.90±2.63%），GAC 接触器对 DBPFP 的去除贡献最大（占总去除率的 60.63±16.64%）。不同结构类型的 DBPFPs 的去除率按以下顺序排列：卤代硝基烷烃（58.50%）>卤代醛（33.62%）>卤代乙酸（HAAs，28.13%）>卤代烷烃（20.46%）>卤代酮（13.46%）>亚硝胺（10.23%）>卤代腈（-8.82%）>卤代烯烃（-9.84%）。与其他 DBP 相比，溴代 DBP（仅含溴原子）和最大卤代 DBP（含 3 和 4 个卤原子）的前体被大量去除。在总 DBPFP 中，三卤甲烷（THMs）、HAAs 和水合氯醛是主要的 DBPs，它们占总目标 DBPs 重量的>92%。Pearson 相关分析（CA）和主成分分析（PCA）表明这些主要 DBPs 之间存在显著关联。典范对应分析（CCA）表明，特定紫外吸光度（SUVA）可以作为 DBPFP 的良好替代参数。生物滤池上游的预氯化可能不会对 SA/GAC 生物过滤对 DBPFP 的整体去除产生重大影响。此外，结果表明，SA/GAC 生物过滤是一种去除无机 DBP 亚氯酸盐的有效方法。
