School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou, 510006, China.
School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou, 510006, China.
J Environ Manage. 2024 Feb 27;353:120191. doi: 10.1016/j.jenvman.2024.120191. Epub 2024 Feb 6.
The daily discharge of rural sewage in China occupies 30 % of the national wastewater discharge, and developing an energy-efficient, easy to operate, and decentralized rural sewage treatment technology becomes an important task. In this work, a novel rural sewage treatment technology, Electrocoagulation enhanced Gravity-Driven Membrane Bioreactor (EC-GDMBR) was exploited for the rural sewage treatment under long-term operation (160 days). Two EC-GDMBRs with various module structures of ceramic membrane (horizontal module and side module) not only displayed the desirable effluent quality, but also sustained the stable flux (8-13 LMH). The electrocoagulation, electrooxidation, biodegradation, and separation in EC-GDMBRs were able to synergistically remove the particle matter, organic (COD effluent <11.6 ± 1.2 mg/L) and nutrients (NH-N effluent <0.1 mg/L, TN effluent <8.5 mg/L, TP effluent <0.05 mg/L). Besides, the high permeability of ceramic membrane and large porosity of biofilm on its surface improved the sustainability of stable flux during the long-term operation. Moreover, by analyzing bacterial abundance, Extracellular Polymeric Substances, Adenosine Tri-Phosphate and Confocal Laser Scanning Microscopy, a large number of microorganisms grew and accumulated on the carrier, as well as formed the biofilm (23.46-659.9 μm), while Nitrobacteria (1.6-4.1 %) and Nitrate (0.01-0.06 %) exited in the carrier biofilms, promoting the nitrogen removal. Compared with EC-GDMBR with side module of ceramic membrane, EC-GDMBR with horizontal module of ceramic membrane has advantages in flux behavior, organic/nutrient removal, microbial abundance/activity, abundance of nitrogen removal functional bacteria and water permeability of biofilm, because the ceramic membrane of horizontal module can promote the uniform growth of biofilm and improve the uniformity of flow penetration distribution. In general, the findings of this work verify the reliability of EC-GDMBR for the sustainable operation of wastewater treatment and improve its application value of rural sewage treatment.
中国农村污水日排放量占全国污水排放量的 30%，开发一种高效节能、易于操作、分散式的农村污水处理技术成为当务之急。在这项工作中，我们开发了一种新型的农村污水处理技术——电絮凝增强重力驱动膜生物反应器（EC-GDMBR），用于长期运行（160 天）下的农村污水处理。两个 EC-GDMBR 采用不同的陶瓷膜模块结构（水平模块和侧模块），不仅表现出理想的出水水质，而且还保持了稳定的通量（8-13 LMH）。EC-GDMBR 中的电絮凝、电氧化、生物降解和分离能够协同去除颗粒物质、有机物（COD 出水<11.6±1.2mg/L）和营养物质（NH-N 出水<0.1mg/L，TN 出水<8.5mg/L，TP 出水<0.05mg/L）。此外，陶瓷膜的高渗透性和其表面生物膜的大孔隙率提高了长期运行过程中稳定通量的可持续性。此外，通过分析细菌丰度、胞外聚合物、三磷酸腺苷和共聚焦激光扫描显微镜，大量微生物在载体上生长和积累，并形成生物膜（23.46-659.9μm），同时载体生物膜中存在硝化菌（1.6-4.1%）和硝酸盐（0.01-0.06%），促进了氮的去除。与具有侧模块陶瓷膜的 EC-GDMBR 相比，具有水平模块陶瓷膜的 EC-GDMBR 在通量行为、有机物/营养物去除、微生物丰度/活性、氮去除功能细菌丰度和生物膜水渗透性方面具有优势，因为水平模块的陶瓷膜可以促进生物膜的均匀生长，提高流穿透分布的均匀性。总的来说，这项工作的结果验证了 EC-GDMBR 用于废水处理可持续运行的可靠性，并提高了其在农村污水处理中的应用价值。
