Dynamic changes of the fouling layer in forward osmosis based membrane processes for municipal wastewater treatment
Dynamic changes of the fouling layer in forward osmosis based membrane processes for municipal wastewater treatment
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城市污水处理正渗透膜工艺中污垢层的动态变化
DOI：
10.1016/j.memsci.2017.12.055
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发表时间：
2018-03-01
影响因子：
9.5
通讯作者：
Cui, Fuyi
中科院分区：
文献类型：
--
作者：
Sun, Yan;Tian, Jiayu;Cui, Fuyi
在这项工作中，污染层的组成作为一个功能的运行时间的动态变化进行了系统的研究和比较，在正渗透（FO）为基础的膜工艺处理城市污水。从四个不同的操作周期（3，8，16和30天）收集污染的膜，并准备用于定量分析的有机和无机污垢和显微镜观察共聚焦激光扫描显微镜（CLSM）。采用平板计数法和Illumina MiSeq测序法分别对细菌浓度和群落结构的动态变化进行了表征。结果表明，随着运行时间的延长，直接FO膜表面沉积的有机污染物、无机物和细菌数量呈逐渐增加的趋势，导致膜的污染阻力相应增加，水通量下降。对于OMBR，除多糖和蛋白质等有机污染物外，无机污染物和膜表面细菌浓度在运行8 d后均达到平台期，导致膜的污染阻力和通量降低。细菌群落分析表明，OMBR生物膜中有2个优势菌属，而直接FO膜表面的细菌群落多样性较高，但丰度较低。
In this work, the dynamic changes in the composition of fouling layer as a function of operating time were systematically investigated and compared in forward osmosis (FO) based membrane processes for municipal wastewater treatment. Fouled membranes were collected from four different operational cycles (3, 8, 16 and 30 days) and prepared for quantitative analyses of organic and inorganic foulants and microscopic observation by confocal laser scanning microscopy (CLSM). Moreover, the dynamic changes of bacterial concentration and community structure were characterized by the plate count method and Illumina MiSeq sequencing, respectively. The results showed that with the extension of operation time, the amount of organic foulants, inorganic species and bacteria deposited on the membrane surface exhibited a gradual increase trend in direct FO, resulting in a corresponding increase of fouling resistance and decline of water flux. As for OMBR, apart from the organic foulants such as polysaccharides and proteins, both the inorganic species and membrane surface bacterial concentration reached to a plateau phase after 8 days of operation, leading to a much lower fouling resistance and flux reduction. The bacterial community analysis indicated that two dominant genus were detected in the biofilm of OMBR; however, the bacterial community on the membrane surface of direct FO exhibited a significantly higher diversity but with a lower abundance.