Yang Hai-Yan, Xing Jia-Jian, Wang Can, Sun Guo-Sheng, Zhao Yan, Liang Heng, Xu Ye-Qin, Li Gui-Bai
Guangdong GDH Water Co., Ltd., Shenzhen 518021, China.
School of Environmental and Municipal Engineering, Harbin Institute of Technology, Harbin 150090, China.
Huan Jing Ke Xue. 2017 Mar 8;38(3):1046-1053. doi: 10.13227/j.hjkx.201608028.
Pilot-scale performances for ultrafiltration of Dongjiang river water without and with micro-coagulation and coagulation-adsorption-sedimentation pretreatments were conducted to investigate the effects of pretreatments on hydraulic irreversible fouling of ultrafiltration short processes. Scanning electron microscope (SEM) imaging, high performance size exclusion chromatography (HPSEC) and fluorescence excitation-emission matrix (EEM) were employed to identify foulants responsible for irreversible fouling during ultrafiltration with and without pretreatments. The results showed that the hydraulic irreversible fouling rate was 0.16 kPa·d with micro-coagulation pretreatment at 10 L·(m·h), while the rate without pretreatment was 0.32 kPa·d at the same flux. Meanwhile, the fouling rate with coagulation-adsorption-sedimentation pretreatment was almost zero at the same flux. Furthermore, when the flux increased to 17 L·(m·h), the irreversible fouling was not observable with coagulation-adsorption-sedimentation pretreatment (backwashing every 24 hours). Properties of foulants from external membrane and internal membrane after backwashing showed that the protein-like and fulvic-like substances were responsible for irreversible fouling in Dongjiang river water. Furthermore, structural alteration of cake layer resulted in less cake resistance and higher backwash efficiency after micro-coagulation pretreatment, leading to less irreversible fouling. Coagulation-adsorption-sedimentation pretreatment decreased irreversible fouling with higher removal efficiency of protein-like and fulvic substances, which were the foulants responsible for irreversible fouling during ultrafiltration. Both micro-coagulation and coagulation-adsorption-sedimentation pretreatments decreased irreversible fouling during ultrafiltration short process.
进行了东江河水超滤的中试实验，分别考察了无预处理、微絮凝预处理以及混凝-吸附-沉淀预处理对超滤短流程水力不可逆污染的影响。采用扫描电子显微镜（SEM）成像、高效尺寸排阻色谱（HPSEC）和荧光激发-发射矩阵（EEM）来识别有无预处理时超滤过程中导致不可逆污染的污染物。结果表明，在10L·(m²·h)的通量下，微絮凝预处理的水力不可逆污染速率为0.16kPa·d，而无预处理时在相同通量下的速率为0.32kPa·d。同时，在相同通量下，混凝-吸附-沉淀预处理的污染速率几乎为零。此外，当通量增加到17L·(m²·h)时，采用混凝-吸附-沉淀预处理（每24小时反冲洗一次）未观察到不可逆污染。反冲洗后外膜和内膜污染物的性质表明，东江水中的类蛋白质和类富里酸物质是导致不可逆污染的原因。此外，微絮凝预处理后滤饼层结构的改变导致滤饼阻力减小，反冲洗效率提高，从而减少了不可逆污染。混凝-吸附-沉淀预处理通过更高的类蛋白质和类富里酸物质去除效率降低了不可逆污染，这些物质是超滤过程中导致不可逆污染的污染物。微絮凝和混凝-吸附-沉淀预处理均降低了超滤短流程中的不可逆污染。
