Abstract：
The multi-soil-layering (MSL) systems is an emerging solution for environmentally-friendly and cost-effective treatment of decentralized rural domestic wastewater. However, the role of the seemingly simple permeable layer has been overlooked, potentially holding the breakthroughs or directions to addressing suboptimal nitrogen removal performance in MSL systems. In this paper, the mechanism among diverse substrates (zeolite, green zeolite and biological ceramsite) coupled microorganisms in different systems (activated bacterial powder and activated sludge) for rural domestic wastewater purification was investigated. The removal efficiencies performed by zeolite coupled with microorganisms within 3 days were 93.8% for COD, 97.1% for TP, and 98.8% for NH4+-N. Notably, activated sludge showed better nitrification and comprehensive performance than specialized nitrifying bacteria powder. Zeolite attained an impressive 89.4% NH4+-N desorption efficiency, with a substantive fraction of NH4+-N manifesting as exchanged ammonium. High-throughput 16S rRNA gene sequencing revealed that aerobic and parthenogenetic anaerobic bacteria dominated the reactor, with anaerobic bacteria conspicuously absent. And the heterotrophic nitrification-aerobic denitrification (HN-AD) process was significant, with the presence of denitrifying phosphorus-accumulating organisms (DPAOs) for simultaneous nitrogen and phosphorus removal. This study not only raises awareness about the importance of the permeable layer and enhances comprehension of the HN-AD mechanism in MSL systems, but also provides valuable insights for optimizing MSL system construction, operation, and rural domestic wastewater treatment.
摘要：
多土壤分层（MSL）系统是一种新兴的解决方案，用于对分散的农村生活污水进行环保和经济有效的处理。然而,看似简单的渗透层的作用被忽视了，潜在的突破或方向，以解决MSL系统中次优的脱氮性能。在本文中,不同基质(沸石，研究了绿色沸石和生物陶粒）在不同系统（活性菌粉和活性污泥）中的耦合微生物用于农村生活污水净化。沸石与微生物联用3天内对COD的去除率为93.8%,TP为97.1％，NH4+-N为98.8%。值得注意的是,活性污泥比专用硝化细菌粉具有更好的硝化性能和综合性能。沸石获得了令人印象深刻的89.4％NH4-N解吸效率，大量的NH4-N表现为交换铵。高通量16SrRNA基因测序显示，需氧和孤雌生殖厌氧菌主导了反应器，明显缺乏厌氧菌。异养硝化-好氧反硝化(HN-AD)过程显著,存在反硝化磷积累生物（DPAOs），可同时去除氮和磷。这项研究不仅提高了人们对渗透层重要性的认识，而且增强了对MSL系统中HN-AD机制的理解，而且还为优化MSL系统构建提供了有价值的见解，操作,和农村生活污水处理。
