Browsing by Author "Lin, Justin Chun-Te"

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Application of nanosilver surface modification to RO membrane and spacer for mitigating biofouling in seawater desalination
(2009-08-01)
Yang, Hui-Ling
;
Lin, Justin Chun-Te
;
Huang, Chihpin
;
環境工程研究所
;
Institute of Environmental Engineering
Biofouling is one the most critical problems in seawater desalination plants and science has not yet found effective ways to control it. Silver compounds and ions are historically recognized for their effective antimicrobial activity. Nanosilver particles have been applied as a biocide in many aspects of disinfection, including healthcare products and water treatment. This study proposes an innovative biofouling control approach by surface modification of the RO membrane and spacer with nanosilver coating. A chemical reduction method was used for directly coating nanosilver particles on the membrane sheet and spacer. The surface-modified membrane and spacer were tested for their antifouling performance in a cross-flow flat-sheet membrane cell, which is a part of a pilot plant in Wukan desalination plant. The silver-coating membranes and spacers, along with an unmodified membrane sheet, were tested in the membrane cell and compared on the basis of their antifouling performance. Permeate flux decline and salt rejection was continuously monitored through the testing period. Meanwhile regrowth of microbial populations on the membrane cell was quantified by a unique microbial counting every three to four days. The results showed that both silver-coated membrane (Ag-cM) with uncoated spacer and silver-coated spacer (Ag-cS) with uncoated membrane perforemed better than the unmodified membrane and spacer (Un-MS), in terms of much slower decrease in permeate flux and TDS rejection. However, the effect of silver-coated spacer on antimicrobial activity was more lasting. In the silver-coated spacer test, there was almost no multiplication of cells detected on the membrane during the whole testing period. Besides, the cells adhering to the membrane seemed to lose their activity quickly. According to the RO performance and microbial growth morphology, the nanosilver coating technology is valuable for use in biofouling control in seawater desalination. (C) 2009 Elsevier Ltd. All rights reserved.
Boron removal with UTC-series reverse osmosis filtration
(2013-03-01)
Chiang, Andrew Cheng-Ting
;
Lin, Justin Chun-Te
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Wijayanti, Dewi Ratna
;
Lee, Duu-Jong
;
環境工程研究所
This study compared performance on boron rejection in seawater reverse osmosis (SWRO) membrane filtration in a high pressure cross-flow cell. Real seawaters were sampled at the north, east and south coast of Taiwan and the intake ports of SWRO plants in Penghu and Matsu islands. Four types of flat-sheet RO membranes (SG from GE Osmonics and UTC80, UTC80A, and UTC80S from Toray Industries) were tested. Permeate flux, feed flow rate and boron concentrations at room temperature were recorded over testing time. The UTC-series membranes have better performance on both boron and sodium rejection than SG membrane at all tested pH's. Test data sets were available for the first time using SWRO membrane for boron rejection from seawaters in Taiwan. (c) 2012 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.
Boron removal with UTC-series reverse osmosis filtration
(2013-03-01)
Chiang, Andrew Cheng-Ting
;
Lin, Justin Chun-Te
;
Wijayanti, Dewi Ratna
;
Lee, Duu-Jong
;
防災與水環境研究中心
This study compared performance on boron rejection in seawater reverse osmosis (SWRO) membrane filtration in a high pressure cross-flow cell. Real seawaters were sampled at the north, east and south coast of Taiwan and the intake ports of SWRO plants in Penghu and Matsu islands. Four types of flat-sheet RO membranes (SG from GE Osmonics and UTC80, UTC80A, and UTC80S from Toray Industries) were tested. Permeate flux, feed flow rate and boron concentrations at room temperature were recorded over testing time. The UTC-series membranes have better performance on both boron and sodium rejection than SG membrane at all tested pH's. Test data sets were available for the first time using SWRO membrane for boron rejection from seawaters in Taiwan. (c) 2012 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.
Effect of Anti-solvent Conditions on Low Density Supercritical Fluids Precipitation of Zeaxanthin Palmitates from Lycium Barbarum Fruits
(2014-03-01)
Lin, Kuo-Li
;
Chng, Lee-Muei
;
Lin, Justin Chun-Te
;
Hsu, Shih-Lan
;
Young, Chiu-Chung
A low density supercritical anti-solvent (SAS) precipitation of zeaxanthin palmitates (ZP) from Lycium barbarum (LB) to increase the purity of zeaxanthin palmitates in precipitates and to reduce the mean particle size of those precipitates was studied. The experimental data herein reveal that the purity of zeaxanthin palmitates increased with pressure, and total yield and purity increased with feed flow rate, but the effect of the anti-solvent time was trivial. A three-factor center composited schemed response surface method was used to study the effects of pressure, feed flow rate and time on total yield, purity, recovery and particle size of the precipitates. A precipitated powder with a mean particle size of approximately 2800 nm, a purity of 92.5%, a total yield of 66% and a recovery of 71%, was obtained at a pressure of 150 bar, a feed flow rate of 0.2 mL/min and an anti-solvent injection time of 48 min. This study demonstrated that low-density SAS precipitation promotes the purity of micro-sized ZP precipitates.
Effect of Anti-solvent Conditions on Low Density Supercritical Fluids Precipitation of Zeaxanthin Palmitates from Lycium Barbarum Fruits
(2014-03-01)
Lin, Kuo-Li
;
Chng, Lee-Muei
;
Lin, Justin Chun-Te
;
Hsu, Shih-Lan
;
Young, Chiu-Chung
A low density supercritical anti-solvent (SAS) precipitation of zeaxanthin palmitates (ZP) from Lycium barbarum (LB) to increase the purity of zeaxanthin palmitates in precipitates and to reduce the mean particle size of those precipitates was studied. The experimental data herein reveal that the purity of zeaxanthin palmitates increased with pressure, and total yield and purity increased with feed flow rate, but the effect of the anti-solvent time was trivial. A three-factor center composited schemed response surface method was used to study the effects of pressure, feed flow rate and time on total yield, purity, recovery and particle size of the precipitates. A precipitated powder with a mean particle size of approximately 2800 nm, a purity of 92.5%, a total yield of 66% and a recovery of 71%, was obtained at a pressure of 150 bar, a feed flow rate of 0.2 mL/min and an anti-solvent injection time of 48 min. This study demonstrated that low-density SAS precipitation promotes the purity of micro-sized ZP precipitates.
Low density supercritical fluids precipitation of 9-cis and all trans-beta-carotenes enriched particulates from Dunaliella salina
(2013-07-19)
Chen, Jian-Ren
;
Wu, Jia-Jiuan
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Lin, Justin Chun-Te
;
Wang, Yuan-Chuen
;
Young, Chiu-Chung
In this study, supercritical anti-solvent (SAS) pulverization coupled with reverse phase elution chromatography was employed to isolate 9-cis and trans-beta-carotenes from Dunaliella saline. Total concentration of 9-cis (134.7 mg/g) and trans-beta-carotene (204.2 mg/g) was increased from 338.9 mg/g of the ultrasonic extract to 859.7 mg/g (338.9 for 9-cis and 520.8 for trans) of the elution fraction. The SAS pulverization of the collected fraction further produced submicron-sized particulates containing 932.1 mg/g (355.6 for 9-cis and 576.5 for trans) of total beta-carotenes with a recovery of 86.3% (83.9% for cis and 87.8% for trans). Effects of two SAS operational conditions on the purity, recovery of total beta-carotenes, mean size and morphology of the precipitates were obtained from an experimentally designed method. Generation of micronized particulates enriched with 9-cis and trans-beta-carotenes by low-density SAS was proved to be feasible and environmental benign. (C) 2013 Elsevier B.V. All rights reserved.
Low density supercritical fluids precipitation of 9-cis and all trans-beta-carotenes enriched particulates from Dunaliella salina
(2013-07-19)
Chen, Jian-Ren
;
Wu, Jia-Jiuan
;
Lin, Justin Chun-Te
;
Wang, Yuan-Chuen
;
Young, Chiu-Chung
In this study, supercritical anti-solvent (SAS) pulverization coupled with reverse phase elution chromatography was employed to isolate 9-cis and trans-beta-carotenes from Dunaliella saline. Total concentration of 9-cis (134.7 mg/g) and trans-beta-carotene (204.2 mg/g) was increased from 338.9 mg/g of the ultrasonic extract to 859.7 mg/g (338.9 for 9-cis and 520.8 for trans) of the elution fraction. The SAS pulverization of the collected fraction further produced submicron-sized particulates containing 932.1 mg/g (355.6 for 9-cis and 576.5 for trans) of total beta-carotenes with a recovery of 86.3% (83.9% for cis and 87.8% for trans). Effects of two SAS operational conditions on the purity, recovery of total beta-carotenes, mean size and morphology of the precipitates were obtained from an experimentally designed method. Generation of micronized particulates enriched with 9-cis and trans-beta-carotenes by low-density SAS was proved to be feasible and environmental benign. (C) 2013 Elsevier B.V. All rights reserved.
Measurement of transparent Alcian blue-stainable materials in freshwater by a centrifugation-based method
(2017-02-01)
Nguyen Thi Thuy
;
Huang, Chihpin
;
Lin, Justin Chun-Te
;
環境工程研究所
;
防災與水環境研究中心
Transparent exopolymer particles (TEP) are particularly abundant in diverse aqueous environments and regarded as a main contributor to biofilm and membrane biofouling. In this study, we optimized a centrifugation- based approach to analyze Alcian blue-stainable materials (ABSM), which cover TEP and acidic polysaccharide-related substances, for reservoirs in Taiwan. Stability of the dye in terms of time and acidic conditioning was firstly monitored intensively at pH 2.5 and 4.0, with and without stirring. Absorbance of dye-reacted solutions of the reference materials ( xanthan gum) and natural ABSM sampled from reservoirs were both examined under different relative centrifugal forces (RCF). Separation efficiency of complexes generated between Alcian blue and the targeting materials under broad range of RCFs (from 1,089 to 34,957 xG) was further assessed based on particle hydrodynamic size distributions, which then provided an insight of their fates that former methods were not addressed. Our results showed centrifugation at high RCFs ( higher than 12,096 xG) was effective to separate these complexes comparing with previous studies only conducted at lower RCFs. Application of the proposed method for five freshwater samples revealed notable high concentrations of Alcian blue-stainable dissolved fraction that could be a critical factor in developing feasible antifouling strategies for membranes used in water treatment.
Membrane Fouling Mitigation: Membrane Cleaning
(2010)
Lin, Justin Chun-Te
;
Lee, Duu-Jong
;
Huang, Chihpin
;
環境工程研究所
;
Institute of Environmental Engineering
Fouling is an inevitable hurdle limiting flux and performance of membrane processes. This paper reviewed the literature studies on physical cleaning methods and chemical cleaning and commented on the indices for cleaning efficiencies therein used in literature works.
Pre-Treatment of Natural Organic Matters Containing Raw Water using Coagulation
(2010)
Cheng, Ya-Ling
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Wong, Ruei-Jyun
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Lin, Justin Chun-Te
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Huang, Chihpin
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Lee, Duu-Jong
Coagulation is a commonly adopted process as a pretreatment step for minimizing membrane fouling. Three coagulants, polyaluminum chloride (PACl), alum, and FeCl3 were tested under four mixing-settling schemes for turbidity and natural organic matters (NOM) removal. The organic matters in the raw waters were fractionated by high performance size exclusion chromatography (HP-SEC) system and were characterized using the excitation-emission matrix (EEM) fluorescence spectra. Sufficient rapid mixing and slow mixing or applying two-stage coagulation benefit turbidity removal using PACl or FeCl3 under oelectrostatic patch coagulationo (EPC) mechanism. The EPC mechanism is not efficient for alum coagulation. At higher coagulant doses, the NOM removal is not affected by mixing condition. Intensive rapid mixing alone benefits NOM removal using PACl or FeCl3. Alum is a poor coagulant for NOM removal under EPC mechanism.
Profiling vertical distribution of scalants in RO membranes by LA-ICP-MS and fouling models
(2014-11-05)
Lin, Justin Chun-Te
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Wang, Tsinghai
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Ku, Yu-Hsuan
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Hsieh, Yi-Kong
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Wang, Chu-Fang
The vertical distribution of scalants as a result of 24 h of filtration of simulated low-level radioactive liquid waste in the reverse osmosis (RO) membranes was characterized by means of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Our results suggested that the development of scalants is associated with the formation of metal hydroxide colloids, while these colloids might penetrate relatively deeper into the membrane under the acid environment than under the alkaline environment. Fitting with a two-phase fouling Hermia\'s model suggested that the development of cake-like scalants in the first 5 h under alkaline environment is responsible for hindering the assess of metal hydroxides into the membrane so that they would not penetrate as deep as they do under the acid environment. (C) 2014 Elsevier B.V. All rights reserved.
Release of silver nanoparticle from nanocomposite membranes in water treatment processes
(2014-08-10)
Lin, Justin Chun-Te
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Ling, Ronald
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Qian, Jianjiang
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Yang, Hui-Ling
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Huang, Chihpin
Seasonal fouling on seawater desalination RO membrane
(2010-01-15)
Yang, Hui Ling
;
Huang, Chihpin
;
Lin, Justin Chun-Te
;
環境工程研究所
;
Institute of Environmental Engineering
A pilot study has been performed to investigate the seasonal characteristic of seawater reverse osmosis (RO) membrane fouling. Two batches of experiment during summer and winter were both performed 18 days to provide a clear picture on microbial population variability. The feed water of the pilot from seawater desalination plant has significant difference in temperature and silica content between the two seasons. In our experiments, scaling and biofouling are more serious in summer. And the permeate flux decline is closely related to the rise in microbial population, and it was dominated by cell multiplication rather than adhesion. In addition, the summer cell multiplication is much more abundant. Moreover, the extracellular polymeric substance (EPS) feature intensity detected by Fourier-transform infrared spectroscopy was also stronger in summer. The abundant EPS was one of the major reasons to cause the inorganic matter adsorption. Si, Al, Fe, Ca and Mg were found as the major inorganic foulants deposited on the Ro membranes. Silica and calcium in summer appeared obvious higher amounts than that in winter, which indicated that they should be affected by microbial action directly or indirectly more than other elements. In summary, there exists a seasonal effect on membrane scaling and fouling, and scaling is associated with biofouling in some degree. Further researches could be focus on actual association between microbial action and inorganic fouling. (C) 2009 Elsevier B.V. All rights reserved.
Temporal variation and interaction of full size spectrum Alcian blue stainable materials and water quality parameters in a reservoir
(2015-07-01)
Nguyen Thi Thuy
;
Lin, Justin Chun-Te
;
Juang, Yaju
;
Huang, Chihpin
;
環境工程研究所
This paper reports on the fate of different fractions of Alcian blue, (AB) stainable material in Pao-Shan reservoir, Taiwan, in a one-year study (2013-2014) and an intensive study during phytoplankton bloom (2014). The interactions between the fractions, including AB stained particles, particle and colloidal transparent exopolymer particles (pTEP and cTEP), dissolved acid polysaccharide (dAPS), and their relationship to other water quality parameters were analyzed. The Flow Cytometer and Microscope (FlowCAM) was for first time used to characterize AB stained particles. The results of the one-year study likely showed relationships of pTEP concentration to phytoplankton count and chlorophyll a, while in the intensive study, AB stained particles abundance and pTEP concentration were correlated neither phytoplankton count nor chlorophyll a, but strongly positively correlated with some phytoplankton species\' abundance. The difference indicates that sampling frequency and phytoplankton composition should be addressed for studying the links between AB stained fractions and phytoplankton. The interaction between different AB stained fractions further suggests that the majority of AB stained particles and pTEP would be directly generated by some phytoplankton species, whereas their abiotic generation by cTEP or dAPS may only have contributed partly to their formation. This differs from previous studies which generally posited that pTEP are mainly formed abiotically from dissolved precursors. Successful application of FlowCAM for visualization of AB stained particles recommends this technique by which particle morphologies can be conserved and morphological features of particle can be simultaneously elucidated. (C) 2015 Elsevier Ltd. All rights reserved.
Visualization of clogs developed from interaction between APDC and low-level radwaste relevant nuclides on RO membranes: A LA-ICP-MS study
(2014-04-15)
Chen, Lian-Song
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Wang, TsingHai
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Hsieh, Yi-Kong
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Hsu, Chien-Hua
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Lin, Justin Chun-Te
In this study, we used LA-ICP-MS to visualize the fouling induced by seeded filtration for efficient removing liquid low-level radwaste relevant nuclides using a reverse osmosis (RO) membrane. Evidenced by a significant permeate flux drop, these APDC additives pronouncedly increased the rejection by around 20% (from 68% to 84%) for cobalt, 30% for strontium (from 55% to 71%), and 70% for cesium (from 20% to 34%). Surface mapping using LA-ICP-MS showed that the hot zones of Co, Sr, and Cs in the APDC-Co, APDC-Sr and APDC-Cs systems were perfectly superimposed with the locations of the S moiety of APDC. This suggested that the improved rejection is closely related to the formation of APDC-metal complexes, and the possible coprecipitation of these elements with APDC-metal complexes. Further depth profile analyses revealed that the fouling mainly occurred in the first 2-6 pm of the RO membrane. Fitted with the Hermia model, it was evident that APDC additives facilitate the formation of complete blocking, intermediate blocking, and standard blocking, and as a consequence enhance Co rejection. By contrast, cake formation induced by APDC additives was mainly responsible for the better rejection of Sr and Cs. Importantly, our depth profile analyses undoubtedly suggested that a large particle/colloid is able to penetrate deeply into the membrane despite its pore size is much smaller than those particles/colloids. (C) 2014 Elsevier B.V. All rights reserved.
Water Coagulation Using Electrostatic Patch Coagulation (EPC) Mechanism
(2010)
Cheng, Ya-Ling
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Wong, Ruei-Jyun
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Lin, Justin Chun-Te
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Huang, Chihpin
;
Lee, Duu-Jong
Coagulation of fine particles to form large flocs is an essential step to reach efficient dewatering of wet materials. The electrostatic patch coagulation (EPC) mechanism was applied in this study to remove turbidity and natural organic matters in water using four different dosing-mixing schemes. Sufficient rapid mixing and slow mixing or applying two-stage coagulation benefit removal of turbidity. The EPC mechanism could only efficiently remove organic matters of molecular weight of 7500-10,000Da. Only sufficient rapid mixing is relevant to organic matter removal. The mechanisms for natural organic matters (NOM) removal are proposed to be complexation of ions and NOM to form insoluble aggregates to be separated by membrane filtration.