Zhang Ting, Wu Peng, Shen Yao-Liang, Lü Gang, Xu Yue-Zhong, Samwine Thomas
School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China.
Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou 215009, China.
Huan Jing Ke Xue. 2017 Aug 8;38(8):3399-3405. doi: 10.13227/j.hjkx.201701080.
In order to achieve fast start-up of shortcut nitrification, a continuous stirred tank reactor (CSTR) and a membrane bioreactor (MBR) were selected for a comparative study about the start-up characteristic of shortcut nitrification. The differences in three aspects of the two reactors were investigated, namely start-up time, nitrogen transformation, and sludge performance. The results showed that the start-up of shortcut nitrification was successfully achieved in the CSTR and MBR after 44 and 56 days of operation, respectively, with influent C/N=1, temperature around 30℃±1℃, pH of 7.5-8.0, and dissolved oxygen (DO) of 0.6-1.0 mg·L, as well as combining anoxic/aerobic ratio 1:3 (15 min:45 min) with shortened hydraulic retention time (HRT). The start-up period of the MBR was shorter. On the 14th, 28th, and 56th day, the average nitrite accumulation efficiencies in the CSTR were 51%, 66%, and 89%, respectively, and 50%, 71%, and 93% in the MBR, and nitrate formation rates of the CSTR was successively 7.4, 4.0, and 1.7 mg·(g·h) (NO-N/MLVSS), respectively, and 7.6, 3.5, and 1.0 mg·(g·h) (NO-N/MLVSS) for the MBR. A higher nitrite accumulation efficiency and a lower nitrate formation rate were detected in the MBR on the 28th and 56th day, respectively, which could be beneficial to the fast start-up of shortcut nitrification. During the operation period, the shortcut nitrification sludge in the two reactors was yellow, the sludge volume index (SVI) was between 55 and 110 mL·g, and the mixed liquor volatile suspended solids (MLVSS)/mixed liquor suspended solids (MLSS) ratio was around 0.6-0.8. The good sludge performance created favorable conditions for the fast start-up of shortcut nitrification in both the CSTR and MBR. In conclusion, the MBR exhibited better performance in the fast start-up of shortcut nitrification.
为实现短程硝化的快速启动，选用连续搅拌釜式反应器（CSTR）和膜生物反应器（MBR）对短程硝化的启动特性进行对比研究。考察了两个反应器在启动时间、氮转化和污泥性能三个方面的差异。结果表明，在进水C/N=1、温度约30℃±1℃、pH为7.5 - 8.0、溶解氧（DO）为0.6 - 1.0 mg·L，以及缺氧/好氧比为1:3（15 min:45 min）且水力停留时间（HRT）缩短的条件下，CSTR和MBR分别运行44天和56天后成功实现了短程硝化的启动。MBR的启动周期较短。在第14天、28天和56天，CSTR中平均亚硝酸盐积累效率分别为51%、66%和89%，MBR中分别为50%、71%和93%，CSTR的硝酸盐生成速率依次为7.4、4.0和1.7 mg·(g·h)(NO-N/MLVSS)，MBR的硝酸盐生成速率依次为7.6、3.5和1.0 mg·(g·h)(NO-N/MLVSS)。分别在第28天和56天，MBR中亚硝酸盐积累效率更高，硝酸盐生成速率更低，这有利于短程硝化的快速启动。在运行期间，两个反应器中的短程硝化污泥均呈黄色，污泥体积指数（SVI）在55至110 mL·g之间，混合液挥发性悬浮固体（MLVSS）/混合液悬浮固体（MLSS）比值约为0.6 - 0.8。良好的污泥性能为CSTR和MBR中短程硝化的快速启动创造了有利条件。总之，MBR在短程硝化的快速启动方面表现出更好的性能。
