Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of.Education, Chongqing University, Chongqing, 400045, China.
Shandong Urban and Rural Planning Design Institute, Jinan, 250013, China.
Chemosphere. 2020 Sep;255:126901. doi: 10.1016/j.chemosphere.2020.126901. Epub 2020 Apr 30.
Enhanced nitrate removal from the secondary effluent in municipal wastewater treatment plants (WWTPs) is essential for avoiding water eutrophication. To this end, a vertical baffled solid-phase denitrification reactor (VBSDR) was developed using a starch and polycaprolactone (PCL) blend plate (S-PCL) as a carbon source and biofilm carrier. In this study, we evaluated the denitrification performance and microbial diversity of the VBSDR. The results of the Fourier transform infrared spectroscopy (FTIR), carbon leaching experiment, and scanning electron microscopy (SEM) demonstrated that the S-PCL structure can be attached and degraded more rapidly. Furthermore, the denitrification performance under varied operational conditions, i.e., influent nitrate loading rate (NLR) and operating temperature, was also investigated. Herein, when treating low C/N ratio and low-strength wastewater, a high denitrification rate (DR) [0.33 gN/(L·d)] was achieved. The effect of temperature on DR can be described by the Arrhenius-type equation, which shows that low temperature has a negative influence on DR and nitrate removal efficiency. Furthermore, DR was simultaneously affected by the NLR and temperature. The microbial diversity and community structure were determined by Illumina high-throughput sequencing. The special carbon source led to Acidovorax (denitrifying bacteria) and Flavobacterium (hydrolysis acidifying bacteria) being the VBSDR biofilm's most predominant functional bacteria at the genus level.
从城市污水处理厂（WWTP）的二级出水（secondary effluent）中去除硝酸盐对于避免水体富营养化至关重要。为此，采用淀粉和聚己内酯（PCL）共混板（S-PCL）作为碳源和生物膜载体，开发了垂直折流固相反硝化反应器（VBSDR）。本研究评估了 VBSDR 的反硝化性能和微生物多样性。傅里叶变换红外光谱（FTIR）、碳浸出实验和扫描电子显微镜（SEM）的结果表明，S-PCL 结构可以更快地附着和降解。此外，还研究了不同操作条件（即进水硝酸盐负荷率（NLR）和操作温度）下的反硝化性能。在此，当处理低 C/N 比和低强度废水时，实现了高反硝化率（DR）[0.33 gN/（L·d）]。温度对 DR 的影响可以用阿累尼乌斯型方程来描述，这表明低温对 DR 和硝酸盐去除效率有负面影响。此外，DR 同时受到 NLR 和温度的影响。通过 Illumina 高通量测序确定了微生物多样性和群落结构。特殊的碳源导致反硝化菌（Acidovorax）和水解酸化菌（Flavobacterium）成为 VBSDR 生物膜中最主要的功能菌属。
