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CONTENTS
Volume 10, Number 2, March 2019
 

Abstract
On the purpose of conform the more stringent government regulation for turbid stormwater from construction sites, the feasibility and availability of synthetic fiber placing after the conventional protection barrier were tested in this study. Initially, comparative work on the filtering performance of fiber media and conventional gravel filter was carried out, 27% higher filtration capacity was obtained under the similar operational conditions. The filter efficiency was about 20 to 52% with a varying filter depth of 5 to 15cm, presuming at extreme storm flow conditions (800-1500 m/day of filtration rates). Fiber filter was found to have a similar filtration prosperity as grain media; namely, the separation efficiency is directly and inversely proportional to filter depth and rate, respectively. The effects of filter aid (polyaluminium chloride) on filter performance was also investigated, it greatly affected the turbidity reduction at the dosage of 2 mg/L. At the time of breakthrough, a simple filter washing was carried out, herein, the solid recovery achieved over than 88% and greatly determined by operational parameters. Based on the operational data, the empirical models aimed for predicting filtration efficiency were established, which can effectively determine the required filter depth and filtration area in field.

Key Words
construction sites; fiber filter; stormwater; turbidity

Address
Department of Environmental Engineering, Hanseo University,
46 Hanseo 1-ro, Haemi-myun, Seosan City, Chungcheongnam-do, Republic of Korea

Abstract
To investigate surface properties and interception performances of the new modified PVDF membrane coated with Graphene Oxide (GO) and nano-TiO2 (for short the modified membrane) via the interface polymerization method combined with the pumping suction filtration way, filtration experiments of the modified membrane on Humic Acid (HA) were conducted. Results showed that the contact angle (characterizing the hydrophilicity) of the modified membrane decreased from 80.6+/-1.8 degree to 38.6+/-1.2 degree. The F element of PVDF membrane surface decreased from 60.91% to 17.79% after covered with GO and TiO2. O/C element mass ratio has a fivefold increase, the percentage of O element on the modified membrane surface increased from 3.83 wt% to 20.87%. The modified membrane surface was packed with hydrophilic polar groups (like -COOH, -OH, C-O, C=O, N-H) and a functional hydrophilic GO-polyamide-TiO2 composite configuration. This configuration provided a rigid network structure for the firm attachment of GO and TiO2 on the surface of the membrane and for a higher flux as well. The total flux attenuation rate of the modified membrane decreased to 35.6% while 51.2% for the original one. The irreversible attenuation rate has dropped 71%. The static interception amount of HA on the modified membrane was 158.6 mg/m2, a half of that of the original one (295.0 mg/m2). The flux recovery rate was increased by 50%. The interception rate of the modified membrane on HA increased by 12% approximately and its filtration cycle was 2-3 times of that of the original membrane.

Key Words
GO-TiO2 modified PVDF membrane; hydrophilicity; the flux attenuation rate; antifouling performance; interception behaviors

Address
Dongmei Li, Jinling Liang,Jun Huang, Li Feng, Shaoxiu Li : Faculty of Civil and Transportation Engineering, Guangdong University of Technology, 510006, Guangzhou, Guangdong, China
Mingzhu Huang: Foshan Water Affairs Group Co. Ltd., 528500, Foshan, Guangdong, China
Yongshi Zhan: The Affiliated High School of South China Normal University, 510000, Guangzhou, Guangdong, China.

Abstract
Chronic exposure to atrazine (ATR) raises concerns about adverse effects on reproductive functions. We tested our previously validated filtering device, the OBP-based filter, onto a biological model constituted of cultured swine granulosa cells treated for 48 h with media conditioned with 0.1 or 10 micrometre ATR evaluating cell viability and steroidogenesis. The tested atrazine concentrations did not change granulosa cell viability and no filtering effects was observed following treatments with media prepared with differently filtered water. As for steroidogenesis, treatment of water with OBP -based filter containing 10 micrometre atrazine completely suppressed the stimulatory effect of 10 micrometre atrazine on progesterone production as well as the inhibitory effect of 0.1 micrometre ATR on estradiol-17 production by granulosa cells. Our data demonstrate that the impairment of steroidogenesis induced by ATR is effectively removed after water filtration in the experimental device thus suggesting potential use in biotechnological applications on living cells and/or organisms.

Key Words
atrazine; OBP; granulosa cells; steroidogenesis

Address
Giuseppina Basini, Francesca Grasselli, Simona Bussolati, Virna Conti, Stefano Grolli, Federica Bianchi and Roberto Ramoni: Dipartimento di Scienze Medico-Veterinarie, Università degli Studi di Parma, Via del Taglio 10, 43126 Parma, Italy
Federica Bianchi: Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università degli Studi di Parma,
Parco Area delle Scienze 17/A, 43124 Parma, Italy

Abstract
The D2EHPA/TBP co-extractants immobilized PolyHIPE membrane can be used for the selective separation of Mn (II) from Co (II). By solvent-nonsolvent method, D2EHPA/TBP co-extractants can be effectively immobilized into PolyHIPE membrane. The pore structure of PolyHIPE membrane and the presence of TBP enhance the stability of immobilized co-extractants. The optimal operating conditions for the separation of Mn (II) and Co (II) are feeding phase at pH 5.5, sulfuric acid concentration in the stripping phase of about 50 g/L and stirring speed at 400 rpm. The D2EHPA/TBP co-extractants ratio of 5:1 shows synergetic effect on Mn/Co separation factor about 22.74. The removal rate and recovery rate of Mn (II) is about 98.4 and 97.1%, respectively, while for Co (II) the transport efficiency is insignificant. The kinetic study of Mn (II) transport shows that high initial flux, Jfo = 80.1 (umol/m2s), and maxima stripping flux, Jsmax = 20.8 (micromol/m2s), can be achieved with D2EHPA/TBP co-extractants immobilized PolyHIPE membrane. The stability and reusability study shows that the membrane can maintain a long term performance with high efficiency. High purity of Co (II) and Mn (II) can be recovered from the feeding phase and stripping phase, respectively.

Key Words
Mn (II) and Co (II) separation; D2EHPA; TBP; PolyHIPE membrane; separation factor

Address
Jyh-Herng Chen: Department of Materials and Mineral Resources Engineering, National Taipei University of Technology, 1, Section 3,
Chung-Hsiao East Road, Taipei, 10608, Taiwan, R.O.C.
Le Thi Tuyet Mai: College of Engineering, National Taipei University of Technology, 1, Section 3, Chung-Hsiao East Road, Taipei, 10608, Taiwan, R.O.C.

Abstract
In this study, the removal of MB from saline solutions was evaluated by two methods by adsorption and electrodialysis; the adsorption of the mixture dye/salt on dried orange peel waste (OPW) was studied in batch method. In this study the biosorption of cationic dye by OPW was investigated as a function of initial solution pH, and initial salt (sodium chloride) concentration. The maximal dye uptake at pH >= 3.6 in the absence and in the presence of salt and the dye uptake diminished considerably in the presence of increasing concentrations of salt up to 8 g/L. The Redlich Peterson and Langmuir were the most suitable adsorption models for describing the biosorption equilibrium data of the dye both individually and in salt containing medium. As well, this work deals with the electrodialysis application to remove the dye. Synthetic solutions were used for the investigation of the main operational factors affecting the treatment performance; such as applied voltage, pH, initial dye concentration and ionic strength. The experimental results for adsorption and electrodialysis confirmed the importance of electrostatic interactions on the dye. The electrodialysis process with standard ion exchange membranes enabled efficient desalination of cationic dye solutions; there are two main factors in fouling: electrostatic interaction between cations of dyes and the fixed charged groups of the CEM, and affinity interactions.

Key Words
methylene blue; orange peel waste; adsorption; electrodialysis; fouling; interaction

Address
Laboratory of Water, Membranes and Biotechnologies, Water Researches and Technologies Center (CERTE),
BP 273, Soliman 8020, Tunisia

Abstract
The information matter-element system was built to assess safety of water source. Based on the thought of multiindex fusion, fuzzy matter-element model evaluating water source behavior was constructed by matter-element transform. This model can process comprehensively hydrogeological data, ecological environment, water pollution, surface disturbance, and so on. Water source safety behavior can be described by the qualitative and quantitative manners. According to the development trend of quantitative results, water source safety behavior can be expressed dynamically. As an example, the proposed method was used to assess safety status of 7 water sources in the region. The numerical example shows that the proposed method is feasible and effective, and the evaluation results are reasonable.

Key Words
water source; extension theory; fuzzy matter-element model; dynamic evaluation

Address
Bin Ou, Aimin Gong, Chunxiang He and Shuyan Fu:College of Water Conservancy, Yunnan Agricultural University, Kunming 650201, China
Bin Ou,Shuyan Fu: State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, 210098, China


Abstract
The roles of polypropylene (PP) beads and pH on membrane fouling and treatment efficiency were investigated in a hybrid advanced water treatment process of tubular carbon fiber membranes (ultrafiltration (UF) or microfiltration (MF)) and PP beads. The synthetic feed including humic acid and kaolin flowed inside the membrane, and the permeated contacted the PP beads fluidized in the space between the membrane and the module with UV irradiation and periodic water back-flushing. In the hybrid process of UF (0.05 micrometer) and PP beads, final resistance of membrane fouling (Rf) after 180 min increased as PP beads increased. The turbidity treatment efficiency was the maximum at 30 g/L; however, that of dissolved organic matters (DOM) showed the highest at PP beads 50 g/L. The Rf strengthened as pH of feed increased. It means that the membrane fouling could be inhibited at low alkali condition. The treatment efficiency of turbidity was almost constant independent of pH; however, that of DOM showed the maximum at pH 5. For MF (0.1 micrometer), the final Rf was the minimum at PP beads 40 g/L. The treatment efficiencies of turbidity and DOM were the maximum at PP beads 10 g/L.

Key Words
hybrid process; carbon fiber; membrane; polypropylene bead; pH; water back-flushing

Address
Department of Environmental Sciences & Biotechnology, Hallym University, Gangwon 24252, Korea

Abstract
Mixed matrix membranes (MMMs) of poly (vinyl alcohol) (PVA) containing certain amounts of H-beta zeolite for pervaporation were manufactured by using a solution casting protocol. These zeolite-embedded membranes were then characterized with scanning electron microscope (SEM), X-ray diffraction (XRD) and swelling tests. The membrane separation performance has been examined by means of isopropanol (IPA) dewatering from its highly concentrated aqueous solutions via response surface methodology (RSM). The results have demonstrated that the influences of feed IPA composition (85-95 wt.%), feed temperature (50-70 Celcius degree), zeolite loading (15-25 wt.%) and their interactive influences are all statistically significant on both pervaporation flux (398-1228 g/m2.h) and water/isopropanol separation factor (617-2001). The quadratic models based on the RSM analysis have performed excellently to correlate experimental data with very high determination coefficients and very low relative standard deviations. The optimal pervaporation predictions given by using the RSM models demonstrate a total flux of 953 g/m2.h and separation factor of 1458, and are excellently verified by experimental results. As reflected by these results, PVA MMMs embedded with hydrophilic H-beta zeolite entities have performed considerably better than its pure counterpart and indicated great potential for isopropanol dehydration applications.

Key Words
isopropanol dehydration; pervaporation; H-

Address
Department of Packaging Engineering, Institute of Materials Science & Chemical Engineering,
Tianjin University of Commerce, Tianjin 300134, PR China

Abstract
This study aimed to investigate the effect of temperature and solid retention time (SRT) on membrane fouling in a membrane bioreactors (MBRs). For this purpose, a lab-scale submerged MBR system was used. This system operated at two SRTs of 15 and 5 days, three various temperatures (20, 25 and 30 C) and hydraulic retention time (HRT) of 8 h. The results indicated that decreased the cake layer resistance and increased particles size of foulant due to increasing temperature and SRT. Fourier transform infrared (FTIR) analysis show that the cake layer formed on the membrane surface, contained high levels of proteins and especially polysaccharides in extracellular polymeric substances (EPS) but absorbance intensity of EPS functional groups decreased with temperature and SRT. EEM analysis showed that the peak on the range of Ex/Em=220-240/350-400 in SRT of 15 and temperature of 30 C indicates the presence of fulvic acid in the cake. In addition, as the temperature rise from 20 to 30 C, concentration of soluble microbial products (SMP) increased and COD removal reached 89%. Furthermore, the rate of membrane fouling was found to increase with decreasing temperature and SRT.

Key Words
submerged membrane bioreactor, solid retention time, temperature, membrane fouling

Address
Atoosa Mirzavandi, Hossein Hazrati and Sirous Ebrahimi:Faculty of Chemical Engineering, Sahand University of Technology, Tabriz, Iran
Hossein Hazrati:Environmental Engineering Research Center, Sahand University of Technology, Tabriz, Iran




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