Abstract：
Aluminum (Al)-based drinking water treatment residue (DWTR) has often been attempted to be recycled as dominant ingredient to produce sintered ceramsite for water treatment. This study aimed to determine the long-term performance of DWTR-based ceramsite in treating domestic wastewater based on a 385-d biofilter test and by using physicochemical, metagenomic, and metatranscriptomic analyses. The results showed that the ceramsite-packed biofilter exhibited high and stable capability in removing phosphorus (P) and chemical oxygen demand (COD), with removal efficiencies of 92.6 ± 3.97% and 81.1 ± 14.0% for total P and COD, respectively; moreover, 88-100% of ammonium-nitrogen (N) was normally converted, and the total N removal efficiency reached 80-86% under proper aeration. Further analysis suggested that the forms of the removed P in the ceramsite were mainly NH4F- and NaOH-extractable. Microbial communities in the ceramsite biofilter exhibited relatively high activity. Typically, various organic matter degradation-related genes (e.g., hemicellulose and starch degradations) were enriched, and a complete N-cycling pathway was established, which is beneficial for enriching microbes involved in ammonium-N conversion, especially Candidatus Brocadia, Candidatus Jettenia, Nitrosomonas, and Nitrospira. In addition, the structures of the ceramsite had high stability (e.g., compressive strength and major compositions). The ceramsites showed limited metal and metalloid pollution risks and even accumulated copper from the wastewater. These results demonstrate the high feasibility of applying ceramsite prepared from Al-based DWTR for water treatment.
摘要：
基于铝(Al)的饮用水处理残留物(DWTR)经常被尝试作为主要成分再循环以产生用于水处理的烧结陶粒。本研究旨在基于385-d生物滤池测试并通过使用物理化学，确定DWTR基陶粒在处理生活污水中的长期性能，宏基因组，和元转录组学分析。结果表明，陶粒填充的生物滤池对磷（P）和化学需氧量（COD）具有较高且稳定的去除能力，总P和COD的去除率分别为92.6±3.97%和81.1±14.0%，分别；此外，88-100%的铵态氮(N)通常被转化，在适当的曝气条件下，总氮去除效率达到80-86%。进一步分析表明，陶粒中去除的P的形式主要是NH4F和NaOH可萃取的。陶粒生物滤池中的微生物群落表现出相对较高的活性。通常,各种与有机物降解相关的基因(例如，半纤维素和淀粉降解)被富集，建立了完整的N循环途径，这有利于富集参与铵氮转化的微生物，尤其是布罗卡迪亚念珠菌,CandidatusJettenia,亚硝化单胞菌,和硝基螺旋体。此外,陶粒的结构具有很高的稳定性(例如，抗压强度和主要成分)。陶粒显示出有限的金属和非金属污染风险，甚至从废水中积累了铜。这些结果证明了将由Al基DWTR制备的陶粒用于水处理的高度可行性。
