The Experts below are selected from a list of 3726 Experts worldwide ranked by ideXlab platform
Yu Liu - One of the best experts on this subject based on the ideXlab platform.
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Development of an integrated aerobic granular sludge MBR and reverse osmosis process for municipal Wastewater Reclamation.
Science of The Total Environment, 2020Co-Authors: Siyu Wang, Jia Wei Chew, Yu LiuAbstract:Abstract The Reclamation of municipal Wastewater to obtain high-grade product water is a growing need due to the pressing global water shortage. However, the existing municipal Wastewater treatment plants (WWTPs) with the conventional activated sludge process as a core is not a sustainable engineering solution towards future water sustainability. To tackle such an emerging water-Wastewater nexus, a ferrous-assisted aerobic granular sludge membrane bioreactor and reverse osmosis (AGSMBR-RO) process was developed for municipal Wastewater Reclamation. Results show that about 99.9%, 99.7% and nearly 100% of dissolved organic carbon (DOC), ammonium-N and total phosphorus (TP), respectively, could be removed in the ferrous-assisted AGSMBR-RO process, while the product water could meet the typical NEWater quality of Singapore with respect to the parameters analysed in this study. Moreover, it was found that an addition of 6 mg/L of ferrous could improve the stability of aerobic granular sludge (AGS) through the coagulation and flocculation of suspended flocs as well as phosphorus removal. These in turn led to reduced membrane fouling in both AGSMBR and RO units. Consequently, the proposed process is a promising alternative for municipal Wastewater Reclamation.
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Reverse osmosis concentrate: An essential link for closing loop of municipal Wastewater Reclamation towards urban sustainability
Chemical Engineering Journal, 2020Co-Authors: Xiaoyuan Zhang, Yu LiuAbstract:Abstract With rapid global urbanization and increasing population, the water shortage is becoming a pressing issue for urban sustainability due to limited availability of natural water resource and increasing demand on fresh water. In such a situation, reclaimed municipal Wastewater has been actively considered as a supplementary water source for sustaining future water supply. As such, various biological processes coupled with reverse osmosis (RO) for municipal Wastewater Reclamation to high-grade product water have been gaining growing interest worldwide. However, it should be realized that the use of RO membrane units for water treatment is complicated by the buildup of their concentrated waste. So far, the RO concentrate (ROC) has been recognized as an emerging challenge in municipal Wastewater Reclamation. Thus, this article aims to look into (i) integrated biological treatment-RO processes for municipal Wastewater Reclamation which is an emerging source of ROC, (ii) challenges associated with ROC, (iii) post-treatment of ROC and its impacts on overall energy balance in municipal Wastewater Reclamation processes and (iv) an innovative integrated anaerobic nanofiltration membrane bioreactor-RO process coupled with electrodialysis reversal and ozonation lastly proposed for closing water loop which is imperative in more and more countries. The possible engineering solution to tackle ROC is to minimize its volume by improving the productivity of RO unit in the mainstream Wastewater Reclamation process, with the ultimate goal of crystallization for zero liquid discharge at an affordable energy demand. Moving forward, Reclamation of municipal Wastewater to high-grade product water offers a promising path towards urban sustainability.
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membrane distillation bioreactor mdbr a lower green house gas ghg option for industrial Wastewater Reclamation
Chemosphere, 2015Co-Authors: Shuwen Goh, Yu Liu, Jinsong Zhang, A G FaneAbstract:A high-retention membrane bioreactor system, the Membrane Distillation Bioreactor (MDBR) is a Wastewater Reclamation process which has the potential to tap on waste heat generated in industries to produce high quality product water. There are a few key factors which could make MDBR an attractive advanced treatment option, namely tightening legal requirements due to increasing concerns on the micropollutants in industrial Wastewater effluents as well as concerns over the electrical requirement of pressurized advanced treatment processes and greenhouse gas emissions associated with Wastewater Reclamation. This paper aims to provide a consolidated review on the current state of research for the MDBR system and to evaluate the system as a possible lower Green House Gas (GHG) emission option for Wastewater Reclamation using the membrane bioreactor-reverse osmosis (MBR-RO) system as a baseline for comparison. The areas for potential applications and possible configurations for MDBR applications are discussed.
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Membrane Distillation Bioreactor (MDBR) ‐ A Lower Green‐House‐Gas (GHG) Option for Industrial Wastewater Reclamation
ChemInform, 2015Co-Authors: Shuwen Goh, Yu Liu, Jinsong Zhang, A G FaneAbstract:A high-retention membrane bioreactor system, the Membrane Distillation Bioreactor (MDBR) is a Wastewater Reclamation process which has the potential to tap on waste heat generated in industries to produce high quality product water. There are a few key factors which could make MDBR an attractive advanced treatment option, namely tightening legal requirements due to increasing concerns on the micropollutants in industrial Wastewater effluents as well as concerns over the electrical requirement of pressurized advanced treatment processes and greenhouse gas emissions associated with Wastewater Reclamation. This paper aims to provide a consolidated review on the current state of research for the MDBR system and to evaluate the system as a possible lower Green House Gas (GHG) emission option for Wastewater Reclamation using the membrane bioreactor-reverse osmosis (MBR-RO) system as a baseline for comparison. The areas for potential applications and possible configurations for MDBR applications are discussed.
Euideog Hwang - One of the best experts on this subject based on the ideXlab platform.
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effect of coagulant types on textile Wastewater Reclamation in a combined coagulation ultrafiltration system
Desalination, 2007Co-Authors: Kwangho Choo, Sangjune Choi, Euideog HwangAbstract:Abstract A combination of coagulation and ultrafiltration (UF) processes for textile Wastewater Reclamation was investigated using various types of coagulating chemicals such as polyamine, alum, polyaluminum chloride (PACl), and ferric salts. The potential of the combined system was evaluated to replace the existing treatment processes which are composed of a flotation tank (primary step) and a series of filtration beds including sands, granular carbons, and diatomaceous powders. Regardless of the type and dosage of the coagulants, the UF system achieved substantial colloidal particle removal (>97% of turbidity was removed), but membrane fouling was mitigated in a different manner. The degree of fouling reduction was highly dependent upon the type of coagulants used, even though the turbidity and organics removal efficiencies were nearly the same. The polymeric coagulant aggravated membrane fouling, whereas the inorganic coagulants always helped reduce fouling. A residue of the coagulating polymer, which was added in the primary step and its concentration in the effluent was at an immeasurable level, was found to cause serious membrane fouling. The use of polymeric coagulants should be prevented or minimized if UF is considered for textile Wastewater Reclamation. Polymerized aluminum was found to be the most effective among the coagulants tested, although ferric salt was better than alum in controlling fouling. In particular, it seemed that the characteristics of coagulation chemistry and the coagulated particles had a great impact upon membrane fouling.
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Effect of coagulant types on textile Wastewater Reclamation in a combined coagulation/ultrafiltration system
Desalination, 2007Co-Authors: Kwangho Choo, Sangjune Choi, Euideog HwangAbstract:Abstract A combination of coagulation and ultrafiltration (UF) processes for textile Wastewater Reclamation was investigated using various types of coagulating chemicals such as polyamine, alum, polyaluminum chloride (PACl), and ferric salts. The potential of the combined system was evaluated to replace the existing treatment processes which are composed of a flotation tank (primary step) and a series of filtration beds including sands, granular carbons, and diatomaceous powders. Regardless of the type and dosage of the coagulants, the UF system achieved substantial colloidal particle removal (>97% of turbidity was removed), but membrane fouling was mitigated in a different manner. The degree of fouling reduction was highly dependent upon the type of coagulants used, even though the turbidity and organics removal efficiencies were nearly the same. The polymeric coagulant aggravated membrane fouling, whereas the inorganic coagulants always helped reduce fouling. A residue of the coagulating polymer, which was added in the primary step and its concentration in the effluent was at an immeasurable level, was found to cause serious membrane fouling. The use of polymeric coagulants should be prevented or minimized if UF is considered for textile Wastewater Reclamation. Polymerized aluminum was found to be the most effective among the coagulants tested, although ferric salt was better than alum in controlling fouling. In particular, it seemed that the characteristics of coagulation chemistry and the coagulated particles had a great impact upon membrane fouling.
Kwangho Choo - One of the best experts on this subject based on the ideXlab platform.
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effect of coagulant types on textile Wastewater Reclamation in a combined coagulation ultrafiltration system
Desalination, 2007Co-Authors: Kwangho Choo, Sangjune Choi, Euideog HwangAbstract:Abstract A combination of coagulation and ultrafiltration (UF) processes for textile Wastewater Reclamation was investigated using various types of coagulating chemicals such as polyamine, alum, polyaluminum chloride (PACl), and ferric salts. The potential of the combined system was evaluated to replace the existing treatment processes which are composed of a flotation tank (primary step) and a series of filtration beds including sands, granular carbons, and diatomaceous powders. Regardless of the type and dosage of the coagulants, the UF system achieved substantial colloidal particle removal (>97% of turbidity was removed), but membrane fouling was mitigated in a different manner. The degree of fouling reduction was highly dependent upon the type of coagulants used, even though the turbidity and organics removal efficiencies were nearly the same. The polymeric coagulant aggravated membrane fouling, whereas the inorganic coagulants always helped reduce fouling. A residue of the coagulating polymer, which was added in the primary step and its concentration in the effluent was at an immeasurable level, was found to cause serious membrane fouling. The use of polymeric coagulants should be prevented or minimized if UF is considered for textile Wastewater Reclamation. Polymerized aluminum was found to be the most effective among the coagulants tested, although ferric salt was better than alum in controlling fouling. In particular, it seemed that the characteristics of coagulation chemistry and the coagulated particles had a great impact upon membrane fouling.
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Effect of coagulant types on textile Wastewater Reclamation in a combined coagulation/ultrafiltration system
Desalination, 2007Co-Authors: Kwangho Choo, Sangjune Choi, Euideog HwangAbstract:Abstract A combination of coagulation and ultrafiltration (UF) processes for textile Wastewater Reclamation was investigated using various types of coagulating chemicals such as polyamine, alum, polyaluminum chloride (PACl), and ferric salts. The potential of the combined system was evaluated to replace the existing treatment processes which are composed of a flotation tank (primary step) and a series of filtration beds including sands, granular carbons, and diatomaceous powders. Regardless of the type and dosage of the coagulants, the UF system achieved substantial colloidal particle removal (>97% of turbidity was removed), but membrane fouling was mitigated in a different manner. The degree of fouling reduction was highly dependent upon the type of coagulants used, even though the turbidity and organics removal efficiencies were nearly the same. The polymeric coagulant aggravated membrane fouling, whereas the inorganic coagulants always helped reduce fouling. A residue of the coagulating polymer, which was added in the primary step and its concentration in the effluent was at an immeasurable level, was found to cause serious membrane fouling. The use of polymeric coagulants should be prevented or minimized if UF is considered for textile Wastewater Reclamation. Polymerized aluminum was found to be the most effective among the coagulants tested, although ferric salt was better than alum in controlling fouling. In particular, it seemed that the characteristics of coagulation chemistry and the coagulated particles had a great impact upon membrane fouling.
Arne Verliefde - One of the best experts on this subject based on the ideXlab platform.
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hydrophilic fouling resistant go zno pes membranes for Wastewater Reclamation
Journal of Membrane Science, 2017Co-Authors: Oranso T. Mahlangu, Ruben Nackaerts, Justice M. Thwala, Bhekie B. Mamba, Arne VerliefdeAbstract:Abstract Fouling of pressure-driven membranes remains a major challenge in membrane technology applications to Wastewater treatment as it results in the deterioration of membrane performance. Several studies focusing on novel anti-fouling membranes incorporated with nanoparticles have been carried out but these membranes are not yet a viable solution due to their high energy requirements and poor trace organic compound (TOrC) rejection properties. Therefore, the aim of this study was to fabricate novel energy-efficient polyethersulfone (PES) membranes modified with graphene oxide – zinc oxide (GO-ZnO) and polyvinylpyrrolidone (PVP) for Wastewater Reclamation. A unique membrane synthesis approach called double-casting phase inversion (DCPI) was adopted. In this technique, the casting solutions are cast twice before coagulation. The addition of PVP and GO-ZnO increased membrane pure water permeability, hydrophilicity, and tensile strength while salt rejection increased slightly. The rejection of TOrCs and anti-fouling properties were also improved due to reduction in membrane-solute and membrane-foulant non-electrostatic or affinity interactions. These interactions were computed from contact angles of membranes, foulants and TOrCs based on the Lifshitz-van der Waals/acid-base approach. Compared to commercial NF-270 membranes under similar experimental conditions, the novel membranes exhibited higher fluxes, with less fouling and high rejection of TOrCs. Therefore, novel GO-ZnO membranes have the potential to compete with commercial membranes for Wastewater Reclamation.
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Hydrophilic fouling-resistant GO-ZnO/PES membranes for Wastewater Reclamation
Journal of Membrane Science, 2017Co-Authors: Oranso T. Mahlangu, Ruben Nackaerts, Justice M. Thwala, Bhekie B. Mamba, Arne VerliefdeAbstract:Abstract Fouling of pressure-driven membranes remains a major challenge in membrane technology applications to Wastewater treatment as it results in the deterioration of membrane performance. Several studies focusing on novel anti-fouling membranes incorporated with nanoparticles have been carried out but these membranes are not yet a viable solution due to their high energy requirements and poor trace organic compound (TOrC) rejection properties. Therefore, the aim of this study was to fabricate novel energy-efficient polyethersulfone (PES) membranes modified with graphene oxide – zinc oxide (GO-ZnO) and polyvinylpyrrolidone (PVP) for Wastewater Reclamation. A unique membrane synthesis approach called double-casting phase inversion (DCPI) was adopted. In this technique, the casting solutions are cast twice before coagulation. The addition of PVP and GO-ZnO increased membrane pure water permeability, hydrophilicity, and tensile strength while salt rejection increased slightly. The rejection of TOrCs and anti-fouling properties were also improved due to reduction in membrane-solute and membrane-foulant non-electrostatic or affinity interactions. These interactions were computed from contact angles of membranes, foulants and TOrCs based on the Lifshitz-van der Waals/acid-base approach. Compared to commercial NF-270 membranes under similar experimental conditions, the novel membranes exhibited higher fluxes, with less fouling and high rejection of TOrCs. Therefore, novel GO-ZnO membranes have the potential to compete with commercial membranes for Wastewater Reclamation.
Takashi Asano - One of the best experts on this subject based on the ideXlab platform.
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The Role of Advanced Treatment in Wastewater Reclamation and Reuse
Water Science and Technology, 1999Co-Authors: Rafael Mujeriego, Takashi AsanoAbstract:The role of advanced Wastewater treatment in Wastewater Reclamation and reuse is reviewed. Most of the current Wastewater Reclamation and reuse technologies are essentially derived from those used in water and Wastewater treatment. However, opportunities for adopting technological innovations are much greater for water reuse applications, because reclaimed water will have an economic value as an alternative water supply. Significant progress has been made in developing sound technical approaches to producing high quality and reliable water sources from reclaimed Wastewater. This overview paper provides an assessment of technological advances in water Reclamation and reuse, which has been dubbed as “the greatest challenge of the 21st century.” The paper was presented at the Opening Plenary Session of the IAWQ's Advanced Wastewater Treatment, Recycling and Reuse Conference in Milan, Italy on September 14, 1998.
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Estimating the safety of Wastewater Reclamation and reuse using enteric virus monitoring data
Water Environment Research, 1998Co-Authors: Hiroaki Tanaka, Takashi Asano, Edward D. Schroeder, Hiroaki Tanaka, George TchobanoglousAbstract:The reliability of Wastewater Reclamation and reuse to meet a given annual risk of infection, considering the variability of enteric virus concentrations, has been investigated. Two concepts related to the reliability and safety of Wastewater Reclamation and reuse are presented. The first is reliability, defined as the probability that the risk of infection from enteric viruses in reclaimed Wastewater does not exceed an acceptable risk. The second is based on the expectation of the acceptable annual risk in which the exposure to enteric viruses may be estimated stochastically by numerical simulation. To assess the potential risks associated with the use of reclaimed Wastewater in various reuse applications, four exposure scenarios were tested : golf course irrigation, food crop irrigation, recreational impoundments, and groundwater recharge. Past monitoring data on enteric virus concentrations in unchlorinated secondary effluents in Califomia were used. Because enteric virus concentrations in unchlorinated secondary effluents were found to vary over a wide range, characterizing their variability was found to be extremely important. The reliability criterion of meeting the less than 10 -4 annual risk of infection (less than or equal to one infection per 10 000 population per year) at least 95% of the time was used to assess the safety of using reclaimed Wastewater in the four different exposure scenarios. The methodologies used in this study should be refined, based on a larger enteric virus database developed using standardized field and laboratory protocols.
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The role of physical-chemical treatment in Wastewater Reclamation and reuse
Water Science and Technology, 1998Co-Authors: Avner Adin, Takashi AsanoAbstract:Amid the heightened public health concerns for emerging microorganisms such as cryptosporidium and enteropathogenic E. coli in the water environment, there have been many instances where optimization of chemical coagulation-flocculation processes and filtration of Wastewater was not achieved in practice, resulting in waste of coagulant chemicals and breach of the multiple barriers to pathogen removal and inactivation; thus, unnecessarily endangering public health. In addition, lack of information on the optimization of these processes has hampered the establishment of alternative and more cost-effective Wastewater Reclamation methods for tertiary and advanced Wastewater treatment. Thus, the purpose of this paper is to evaluate the basic factors affecting the optimization of chemical coagulation-flocculation and filtration processes in municipal Wastewater Reclamation and reuse, based on the theoretical developments and practical applications. Reference is also made to the Wastewater treatment processes and operations that can produce reclaimed water with an extremely small probability of enteric virus contamination.
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Wastewater Reclamation and reuse in Japan: overview and implementation examples
Water Science and Technology, 1996Co-Authors: Takashi Asano, M. Maeda, M. TakakiAbstract:To alleviate potentially catastrophic water supply and Wastewater disposal problems as well as expand dependable water supply infrastructure, Japan has launched comprehensive urban Wastewater Reclamation and reuse projects since 1968. In this paper, the status of national policies on Wastewater treatment, Wastewater reuse characteristics, and some Wastewater reuse experiences are presented. Two implementation examples in Tokyo and Fukuoka are discussed in detail, with special reference to application for toilet-flushing in high-rise business buildings and stream restoration and flow augmentation. It was found that the key to the success of Wastewater Reclamation and reuse is the quality of reclaimed water; public acceptance is closely associated with water quality and water supply dependability.
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Environmental assessment for Wastewater Reclamation and reuse projects
Water Science and Technology, 1996Co-Authors: Nick Kontos, Takashi AsanoAbstract:The purpose of an environmental review and assessment is to incorporate environmental considerations into the planning process. Prior to the selection of a specific project alternative, a thorough and unbiased analysis of the environmental impacts of every reasonable project alternative should be made. It is intended that environmental concerns be considered on an equal basis with engineering feasibility, economics, and social considerations in Wastewater Reclamation and reuse. This paper discusses the “procedural” and “substantive” provisions of environmental law in the United States; National Environmental Policy Act (NEPA), and more specifically the law in California; California Environmental Quality Act (CEQA). The procedural aspects require the preparation of an environmental document such as an environmental impact statement (EIS) or an environmental impact report (EIR) and the substantive provisions require mitigation of harmful environmental impacts. Suggested outlines of the content of an EIS and an EIR are provided. Specific impacts associated with Wastewater Reclamation projects such as groundwater impacts and growth inducing impacts are discussed. This paper is intended to be a useful tool for the planning of any Wastewater Reclamation and reuse project. Two examples are given for this purpose.