College of Environmental Science and Engineering, Ocean University of China, 266100 Qingdao, China.
Key Lab of Marine Environment and Ecology, Ministry of Education, Ocean University of China, 266100 Qingdao, China; College of Environmental Science and Engineering, Ocean University of China, 266100 Qingdao, China.
Sci Total Environ. 2019 Dec 20;697:134047. doi: 10.1016/j.scitotenv.2019.134047. Epub 2019 Aug 22.
In this study, simultaneous nitrification and denitrification (SND) process was successfully established in a hybrid sequencing batch biofilm reactor (HSBBR). High removal efficiency of NH-N (98.0±2.4% to 99.8±0.4%) and COD (86.6±4.0% to 91.6±1.8%) was observed in the salinity range of 0.0 to 2.4%. SND via nitrite, replacing SND via nitrate, became the main nitrogen removal pathway at 1.6% and 2.4% salinity. Suspended sludge and biofilm shared similar microbial composition. Dominant genera were substituted by salt-adaptable microbes as salinity increasing. Abundance of autotrophic ammonia-oxidizing bacteria (Nitrosomonas) increased with elevated salinity, while autotrophic nitrite-oxidizing bacteria (Nitrospira) exhibited extreme sensitivity to salinity. The presence of Gemmata demonstrated that heterotrophic nitrification co-existed with autotrophic nitrification in the SND process. Aerobic denitrifiers (Denitratisoma and Thauera) were also identified. Thiothrix, Sedimenticola, Sulfuritalea, Arcobacter (sulfide-based autotrophic denitrifier) and Hydrogenophaga (hydrogen-based autotrophic denitrifier) were detected in both S-sludge and biofilm. The occurrence of ANAMMOX bacteria Pirellula and Planctomyces indicated that ANAMMOX process was another pathway for nitrogen removal. Nitrogen removal in the HSBBR was accomplished via diverse pathways, including traditional autotrophic nitrification/heterotrophic denitrification, heterotrophic nitrification, aerobic and autotrophic denitrification, and ANAMMOX.
在这项研究中，混合序批式生物膜反应器（HSBBR）成功实现了同步硝化反硝化（SND）过程。在盐度范围为 0.0 至 2.4%时，NH-N（98.0±2.4%至 99.8±0.4%）和 COD（86.6±4.0%至 91.6±1.8%）的去除效率很高。在 1.6%和 2.4%的盐度下，通过亚硝酸盐进行的 SND 取代了通过硝酸盐进行的 SND，成为主要的氮去除途径。悬浮污泥和生物膜具有相似的微生物组成。随着盐度的升高，优势属被耐盐微生物取代。随着盐度的升高，自养氨氧化菌（硝化菌）的丰度增加，而自养亚硝酸盐氧化菌（硝化螺菌）对盐度表现出极端的敏感性。动胶菌的存在表明，异养硝化与自养硝化在 SND 过程中共存。还鉴定出好氧反硝化菌（反硝化杆菌和硫杆菌）。硫丝菌、沉积物杆菌、硫单胞菌、弧菌（基于硫化物的自养反硝化菌）和噬氢菌（基于氢气的自养反硝化菌）在 S 污泥和生物膜中均有发现。浮霉菌和黏球菌的出现表明 ANAMMOX 过程是另一种脱氮途径。HSBBR 中的氮去除是通过多种途径完成的，包括传统的自养硝化/异养反硝化、异养硝化、好氧和自养反硝化以及 ANAMMOX。
