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Effects of effluent organic matters on endocrine disrupting chemical removal by ultrafiltration and ozonation in synthetic secondary effluent

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Journal of Environmental Sciences 2019年第2期31卷 57-64页

作者： Xiurong Si Zunfang Hu Ding Ding Xu Fu Civil Engineering Department North China Institute of Aerospace Engineering Shandong Institute of Geophysical and Geochemical Exploration

Endocrine disrupting chemicals(EDCs) in the secondary effluent discharged from wastewater treatment plants are of great concern when water reuse is intended. Ozonation and ultrafiltration(UF) are powerful technologies reported to eliminate EDCs. Due to the importance of effluent organic matters(EfOMs) in secondary effluent, the effects of three kinds of EfOM on the treatment of five EDCs using ozonation and UF were investigated. The three kinds of EfOM studied were humic acid sodium salt(NaAH), bovine serum albumin(BSA)and sodium alginate(NaAg); and the five EDCs were estrone, 17β-estradiol, estriol, 17α-ethynyl estradiol and bisphenol A. The results showed that EfOM accelerated the decay rate of ozone and inhibited the degradation efficiency of EDCs by ozonation in the order NaAH > BSA > NaAg.The ultraviolet absorbance at 280 nm(UVA_(280)) has potential for use as a surrogate indicator to assess EDC removal via ozonation without conducting difficult EDC analyses. When the decline in UVA_(280) exceeded 18%, the five EDCs had been completely removed. The UF behavior of NaAH,BSA and NaAg was found to follow the cake filtration law. The fouling potential of EfOM followed the order NaAg > NaAH > BSA; while EfOM on the membrane surface enhanced EDC removal in the order NaAH > BSA > NaAg. The mean retention rate of the membrane was increased by 24%, 10% and 8%, respectively. The properties of EDCs and EfOM cakes both influenced the EDC removal rates due to adsorption, size exclusion and charge attraction.

关键词： Endocrine disrupting chemicals ultrafiltration Ozonation Effluent organic matters Secondary effluent

Characterization of dissolved organic matter and membrane fouling in coagulation-ultrafiltration process treating micro-polluted surface water

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Journal of Environmental Sciences 2019年第1期31卷 318-324页

作者： Fan Bu Baoyu Gao Qinyan Yue Xue Shen Wenyu Wang Shandong Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and Engineering Shandong University

Coagulation–ultrafiltration(C–UF) is widely used for surface water treatment. With the removal of pollutants, the characteristics of organic matter change and affect the final treatment efficiency and the development of membrane fouling. In this study, we built a dynamic C–UF set-up to carry out the treatment of micro-polluted surface water, to investigate the characteristics of dissolved organic matter from different units. The influences of poly aluminum chloride and poly dimethyldiallylammonium chloride(PDMDAAC) on removal efficiency and membrane fouling were also investigated. Results showed that the dosage of PDMDAAC evidently increased the UV254 and dissolved organic carbon removal efficiencies,and thereby alleviated membrane fouling in the C–UF process. Most hydrophobic bases(HoB)and hydrophobic neutral fractions could be removed by coagulation. Similarly, UF was good at removing HoB compared to hydrophilic substances(HiS) and hydrophobic acid(HoA)fractions. HiS and HoA fractions with low molecule weight accumulated on the surface of the membrane, causing the increase of transmembrane pressure(TMP). Membrane fouling was mainly caused by a removable cake layer, and mechanical cleaning was an efficient way to decrease the TMP.

关键词： Coagulation ultrafiltration Dissolved organic matter Membrane fouling

Influence of floc dynamic protection layer on alleviating ultrafiltration membrane fouling induced by humic substances

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Journal of Environmental Sciences 2020年第4期32卷 10-19页

作者： Baiwen Ma Siqi Wu Bodong Wang Zenglu Qi Yaohui Bai Huijuan Liu Jiuhui Qu Ruijun Wu Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China University of Chinese Academy of Sciences Beijing100049China School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi'an710055China School of Environment State Key Joint Laboratory of Environment Simulation and Pollution ControlTsinghua UniversityBeijing100084China Research Center for Water Quality and Ecology Tsinghua UniversityBeijing100084China State Key Laboratory of Membrane Materials and Membrane Applications Tianjin Motimo Membrane Technology Co.Ltd.Tianjin300457China

Cake layer formation is inevitable over time for ultrafiltration(UF)membrane-based drinking water treatment.Although the cake layer is always considered to cause membrane fouling,it can also act as a"dynamic protection layer",as it further adsorbs pollutants and dramatically reduces their chance of getting to the membrane surface.Here,the UF membrane fouling performance was investigated with pre-deposited loose flocs in the presence of humic acid(HA).The results showed that the floc dynamic protection layer played an important role in removing HA.The higher the solution pH,the more negative the floc charge,resulting in lower HA removal efficiency due to the electrostatic repulsion and large pore size of the floc layer.With decreasing solution pH,a positively charged floc dynamic protection layer was formed,and more HA molecules were adsorbed.The potential reasons were ascribed to the smaller floc size,greater positive charge,and higher roughness of the floc layer.However,similar membrane fouling performance was also observed for the negative and positive floc dynamic protection layers due to their strong looseness characteristics.In addition,the molecular weight(MW)distribution of HA also played an important role in UF membrane fouling behavior.For the small MW HA molecules,the chance of forming a loose cake layer was high with a negatively charged floc dynamic protection layer,while for the large MW HA molecules it was high with a positively charged floc dynamic protection layer.As a result,slight UF membrane fouling was induced.

关键词： ultrafiltration Floc dynamic protection layer Humic substances Fouling alleviation

Nano CuO/g-C_3N_4 sheets-based ultrafiltration membrane with enhanced interfacial affinity,antifouling and protein separation performances for water treatment application

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Journal of Environmental Sciences 2019年第8期31卷 57-69页

作者： Thanigaivelan Arumugham Reshika Gnanamoorthi Amimodu Noel Jacob Kaleekkal Dipak Rana Department of Chemistry School of Advanced Sciences Vellore Institute of Technology (VIT) Department of Integrative Biology School of Bioscience and Technology Vellore Institute of Technology (VIT) Department of Chemical Engineering National Institute of Technology Calicut Department of Chemical and Biological Engineering Industrial Membrane Research Institute University of Ottawa

To improve the interfacial affinity and antifouling properties of polyphenylsulfone(PPSU)membrane, nano CuO/g-C3 N4(g-CN) sheets were synthesized via facile calcination route as one pot synthesis method. The uniformly assembled nanohybrid fillers, CuO on g-CN sheets were confirmed by using XRD, TEM, EDX and FTIR analysis. The non-solvent induced phase inversion technique was used to fabricate the nanohybrid ultrafiltration(UF)membranes by doping different concentration(0.5–1 wt.%) of nano CuO/g-C_3 N_4(g-CN)sheets within the PPSU matrix. The results of contact angle, atomic force microscopy,energy-dispersive X-ray spectroscopy reveal that surface structure and physico-chemical properties of nanohybrid membrane plays lead role in solute interaction and rejection compared to bare membrane, M0. Furthermore, the interfacial affinity of membrane was explored in detail via surface free energy, spreading coefficient, wetting tension and reversible work of adhesion analysis. Nanohybrid UF membrane, with 0.5% of the filler(M1)displayed remarkable permeation flux of 202, 131 L/m2/hr for pure water and protein solution, respectively while maintaining a high protein rejection(96%). Moreover, the exceptional dispersion of the nanosheets in the polymer matrix enhanced FRR(79%) and decreased the overall resistance of M1 compared to the pristine membrane(M0). Overall results suggest that the incorporation of nano sheets is a facile modification technique which improves the comprehensive membrane performance and holds a great potential to be further explored for water treatment.

关键词： ultrafiltration membrane Copper oxide Graphitic carbon nitride Interfacial affinity Antifouling Protein removal

Effect of coagulation pretreatment on the fouling of ultrafiltration membrane

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Journal of Environmental Sciences 2007年第3期19卷 278-283页

作者： DONG Bing-zhi CHEN Yan GAO Nai-yun FAN Jin-chu State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China

The purpose of this study is to understand the effect and mechanism of preventing membrane fouling, by coagulation pretreatment, in terms of fractional component and molecular weight of natural organic matter （NOM）. A relatively higher molecular weight （MW） of hydrophobic compounds was responsible for a rapid decline in the ultrafiltration flux. Coagulation could effectively remove the hydrophobic organics, resulting in the increase of flux. It was found that a lower MW of neutral hydrophilic compounds, which could remove inadequately by coagulation, was responsible for the slow declining flux. The fluxes in the filtration of coagulated water and supernatant water were compared and the results showed that a lower MW of neutral hydrophilic compounds remained in the supernatant water after coagulation could be rejected by a membrane, resulting in fouling. It was also found that the coagulated flocs could absorb neutral hydrophilic compounds effectively. Therefore, with the coagulated flocs formed on the membrane surface, the flux decline could be improved.

关键词： drinking water treatment ultrafiltration coagulation fouling

Flux enhancement during ultrafiltration of produced water using turbulence promoter

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Journal of Environmental Sciences 2006年第6期18卷 1077-1081页

作者： ZHEN Xiang-hua YU Shui-li WANG Bei-fu ZHENG Hai-feng School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

Concentration polarization and membrane fouling remain one of the major hurdles for the implementation of ultrafiltration of produced water. Although many applications for ultrafiltration were already suggested, only few were implemented on an industrial scale. Among those techniques, turbulence promoter can be more simple and effective in overcoming membrane fouling and enhancing membrane flux. As for the result that turbulence promoter increase fluid velocity, wall shear rates and produce secondary flows or instabilities, the influence of turbulence promoter was investigated on permeate flux during produced water ultrafiltration and the potential application of this arrangement for an industrial development. Experimental investigations were performed on 100 KDa molecular weight cut-off PVDF single-channel tubular membrane module using four kinds of turbulence promoters. It is observed that the significant flux enhancement in the range of 83%--164% was achieved while the hydraulic dissipated power per unit volume of permeate decreased from 31%--42%, which indicated that the using of turbulence promoter is more efficient than operation without the turbulence promoter. The effects of transmembrane pressure and cross-flow velocity with and without turbulence promoter were studied as well. Among the four kinds of turbulence promoters, winding inserts with 20.0 mm pitch and 1.0 mm wire diameter showed better performances than the others did.

关键词： hydraulic dissipated power flux enhancement turbulence promoter produced water ultrafiltration

Metabonomics:A Useful Tool to Reveal Underlying Relationships between Altered Chinese Medicine Syndromes and ultrafiltration in Treatment of Heart Failure

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Chinese Journal of Integrative Medicine 2021年第4期27卷 259-264页

作者： GUO Li-jun CHEN Ke-ji SUN Ming-qian WANG An-zhu GAO Feng ZHENG Yuan MA Xiao-chang Graduate School of Beijing University of Chinese Medicine Beijing(100029)China Cardiovascular Disease Center Xiyuan HospitalChina Academy of Chinese Medical SciencesBeijing(100091)China Institute of Basic Medicine Xiyuan HospitalChina Academy of Chinese Medical SciencesBeijing(100091)China

Objective:To reveal the underlying relationships between Chinese medicine(CM)syndromes and ultrafiltration(UF)in the treatment of heart failure based on a metabonomic approach.Methods:Seventeen acute decompensated heart failure(ADHF)patients were enrolled,and their CM syndromes before and after UF were collected.In addition,their venous plasma collected before and after UF was used for liquid chromatographmass spectrometer-based metabonomic analysis.Both reversed phase liquid chromatography and hydrophilic interaction liquid chromatography were used to analyze the plasma samples.Partial least-squares to latent structure-discriminant analyses were used for data analysis.Results:An obvious difference was observed preand post-treatment.A total of 17 potential biomarkers associating with alterd syndromes with UF including hypoxanthine,1-methylhistidine,phytosphingosine,O-decanoyl-R-carnitine,etc.were screened out,showing a significant change after UF.The major adjusted m etabolic pathways were purine metabolism,histidine metabolism,leucine and isoleucine metabolism,arginine and proline metabolism,carnitine shuttle,sphingolipid metabolism and phospholipid metabolism.Conclusions:Metabonomic approach is a useful tool to identify potential biomarkers of altered syndromes link to UF and could provide a theoretical basis for further research on the therapeutic mechanism of UF combined with CM.

关键词： metabonomics heart failure ultrafiltration Chinese medicine

Influence of ultrafiltration membrane on ophiopogonins and homoisoflavonoids in Ophiopogon japonicus as measured by ultra-fast liquid chromatography coupled with ion trap time-of-flight mass spectrometry

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Chinese Journal of Natural Medicines 2017年第2期15卷 121-141页

作者： LIU Chun-Hua QI Jin ZHOU Da-Zheng JU Ai-Chun YU Bo-Yang Jiangsu Key Laboratory of TCM Evaluation and Translational Research China Pharmaceutical UniversityNanjing 211198China Department of Technology Development TianJin Tasly Pride Pharmaceutical Co.Ltd.Tianjin300410China State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China Guizhou Provincial Key Laboratory of Pharmaceutics Guizhou Medical UniversityGuiyang 550004China

ultrafiltration is one of the most fascinating technologies, which makes it possible to improve the quality of traditional medicines for application in the pharmaceutical industry. However, researchers have paid little attention to the effect of ultrafiltration membrane on traditional medicines chemical constituents. In this work, Ophiopogon japonicus(L.f) Ker-Gawl. was used as an example to illuminate the influence of ultrafiltration with different material and molecular weight cut-off(MWCO) membrane on natural chemical constituents as measured by ultra-fast liquid chromatography coupled with ion trap time-of-flight mass spectrometry(UFLC-IT-TOF/MS). Our results indicated that ultrafiltration membrane significantly impacted homoisoflavonoids, especially homoisoflavonoids that were almost completely retained on the polyethersulfone(PES) membrane. We also found that the larger number of aglycone hydroxy and sugar moiety in steroid saponins, the higher the transmittance. Furthermore, the passage rate(%) of ophiogenin type saponins was higher than that of others. The possible adsorptive mechanisms were hydrogen bonding, hydrophobic interactions, and benzene ring interaction by π-π stacking. In conclusion, it is crucial to choose appropriate ultrafiltration membrane based on the characteristics of produce products for application of ultrafiltration technique.

关键词： Homoisoflavonoids Ophiopogon japonicus(L f) Ker-Gawl Ophiopogonins ultrafiltration UFLC-IT-TOF/MS

LUMPED-PARAMETER MODEL OF MASS TRANSFER IN HEMODIALYZER WITH ultrafiltration

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Chinese Journal of Chemical Engineering 1995年第1期3卷 60-65页

作者：张凤宝张国亮陈涛王绍亭天津大学化学工程系天津

1 INTRODUCTIONHemodialysis with ultrafiltration,also called hemodiafiltration(HDF),is a main methodof treatment for patients with chronic renal failure.The HDF procedure providesadequate removals of both small and middle molecular weight toxic substamces fromuremic blood,which is not possible by dialysis or ultrafiltration alone.According toclinical experience[1],the HDF procedure is well accepied by the patients,and thetreatment time is reduced by using it.

关键词： lumped-parameter model hemodialysis ultrafiltration mass transfer perturbation