Yang Yang, Zhou Dandan, Xu Zhengxue, Li Aijun, Gao Hang, Hou Dianxun
Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun, 130021, China.
Appl Microbiol Biotechnol. 2014 Jun;98(12):5737-45. doi: 10.1007/s00253-014-5637-3. Epub 2014 Mar 19.
In this study, the possibility of using backwashed biofilm as seed in an aerobic granular sludge continuous-flow airlift fluidized bed (CAFB) reactor was investigated. After the addition of the inoculated backwashed biofilm, the start-up period of this reactor fed with municipal wastewater was reduced to 25 days, and aerobic granulation and stabilization were enhanced. At steady state, the chemical oxygen demand (COD) removal efficiency and nitrification efficiency were as high as 80-90 and 60 %, respectively. The CAFB was operated continuously and totally for 90 days, and its performance was much more stable when compared with system inoculated with activated sludge. Microbial distribution analyzed by fluorescence in situ hybridization (FISH) showed that the nitrite-oxidizing bacteria (NOB) and ammonium-oxidizing bacteria (AOB) were compatible with heterotrophic bacteria and distributed evenly throughout the granules. Such unique population distribution might be attributed to the low COD level and abundant dissolved oxygen in the entire granule as simulated by the mathematic models. Moreover, scanning electron microscopy revealed broad holes in the granules, which might promote the mass transfer of the nutrients from the surface to the center and enable simultaneous COD removal and nitrification. In conclusion, backwashed biofilm is an alternative seed of the conventional flocculent activated sludge in the aerobic granular sludge system to enhance carbonaceous oxidization and nitrification.
本研究考察了在好氧颗粒污泥连续流气升式流化床（CAFB）反应器中使用反冲洗生物膜作为接种物的可能性。添加接种的反冲洗生物膜后，该以城市污水为进水的反应器启动期缩短至25天，好氧颗粒化和稳定性得到增强。在稳态下，化学需氧量（COD）去除效率和硝化效率分别高达80 - 90%和60%。CAFB连续运行90天，与接种活性污泥的系统相比，其性能更稳定。通过荧光原位杂交（FISH）分析的微生物分布表明，亚硝酸盐氧化菌（NOB）和氨氧化菌（AOB）与异养菌共存且在颗粒中分布均匀。这种独特的种群分布可能归因于数学模型模拟的整个颗粒中较低的COD水平和丰富的溶解氧。此外，扫描电子显微镜显示颗粒中有宽大的孔洞，这可能促进营养物质从颗粒表面到中心的传质，实现COD去除和硝化的同步进行。总之，反冲洗生物膜是好氧颗粒污泥系统中传统絮凝活性污泥的替代接种物，可增强碳氧化和硝化作用。
