bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrated Resources Planning in Australia - Innovative Planning and Management Approaches in Practice
Authors: Beatty Russell , Dawson Matthew , O'Brien Shane , Stewart Brett , Gabriel Grant
Published: August 2018

With much of Australia currently in the grip of one of the worst droughts on record, the focus on balancing supply and demand through the use of Integrated Water Resource Planning approaches has never been more important. Where once it was sufficient to plan for new dams, the falling reliability of traditional surface water supplies and the threat of global warming, which most believe will further reduce rainfall, has led to an acute focus on the role of water conservation, water recycling and rainwater use in securing the water future for both major cities and towns.

This paper provides an overview of the innovative new planning frameworks and modelling approaches that have been developed to support the Integrated Water Resources Planning effort.
Water Stewardship in the Desert: Water Conservation Projects in the Kingdom of Saudi Arabia
Authors: Puffer Matthew , Al-Musallam Loay Bin Ahmed
Published: August 2018

The purpose of this paper is to describe the results of a dynamic water conservation program currently being implemented in the Kingdom of Saudi Arabia (KSA). Responding to a growing water crises and the need to defer the development of future desalination plants, the Ministry of Water & Electricity (MOWE) initially retrofitted 3.2 million households over an 18 month period with aerators and toilet displacement devices. This experience enabled MOWE to expand the programs to high-efficiency showerheads and other conservation devices. MOWE faced significant and unique challenges in implementing the programs due to program needs and cultural structures. Customer follow-up surveys were conducted in the twelve cities and eight provinces targeted by the program. This is an ongoing program where the savings, the issues and customers will be continually surveyed and documented.
The Plan on the Adjustment of Water Distribution System in Korea Waterworks System
Authors: Jeong Jinwoo , Wi Wuk-Ryang , Kang Geum-bai , Lee Kuk-Yang , Park Chang-Shin , Yoo Man-Sik
Published: August 2018

The primary objective of this plan is to consolidate the current water supply system of Korea organized in the unit of city and county into wide area in order to supply the deficient region by fully utilizing the superfluous water volume of neighboring city and county. Furthermore, it also aims to prepare for the penetration of large foreign water supplier into domestic market by securing competitiveness through consolidation of domestic medium and small water suppliers in consideration of the forthcoming market opening. We determined the regions for which supplying system needs to be adjusted by analyze regions with deficient and superfluous water through the forecast of water supply and demand for established life areas. Further, we established plan to utilize the superfluous water volume as an adjust multi-regional water supply system local water supply system such as water supply plan in the life areas, water supply plan between the life areas.
Legal consequences of data reporting and public perception: pitfalls of the regulatory system in municipal wastewater treatment facilities' pursuit of environmental advancement
Authors: Barry Q. C. J. P. , LeBlanc J. G.
Published: August 2018

Municipal wastewater treatment facilities undertake the challenge of furthering governmental and public policy objectives of protecting human health and minimizing negative impacts on the environment by treating wastewater gathered from municipal sewer systems. Current regulations and public opinion often fail to realize that these facilities are not polluters, but rather are treaters of pollution. Municipalities and treatment facilities are completely different creatures than for-profit industries yet broad and general application of environmental legislation often does not acknowledge their unique purpose. Required by law to engage in regular data reporting to regulators, facilities do not receive protection from civil proceedings or prosecution in exchange for this mandatory reporting. Facility operators are reasonably hesitant to volunteer any information at the risk of it later being used against them as an adversarial climate persistently shadows the relationship between facilities and regulators. Internationally recognized principles and practical realities must be considered in developing a regulatory scheme which fosters a philosophy of collaboration between every level of government and municipal wastewater treatment facilities.
Four ‘Well-beings’ - Social, Economic, Environmental & Cultural - A Sustainable Development Approach To Biosolids Management
Authors: Bradley JW , Winefield PB , Mikaere B.
Published: August 2018

In New Zealand, since 2002, it has been mandatory for local government decision-makers to consider the environmental, economic, social and cultural well-being of the community in every decision they make. This applies very much to sludge and biosolids management and is additional to strong resource management laws. This new legislative prescription (particularly the social and cultural imperatives) is creating significant new challenges for the management of sludge and biosolids and New Zealand's experience in this area is considered relevant to all countries and communities that have a strong social agenda and a commitment to the rights and obligations of indigenous people.
Rethinking wastewater biosolids, phosphorus recovery and sustainability
Authors: Davelaar D.
Published: August 2018

This paper aims at bringing about an urgently required, scientific shift of perception in the field of biosolids management and phosphorus recovery from domestic wastewater. The paper shows that under a combination of the prevailing sludge, phosphorus and sustainability paradigms, the worldwide rapidly growing issue on biosolids production leads to a paradox that proper management cannot resolve alone. Change demands for a sound fundamental ecological approach in all sectors involved. To produce low quantities of biosolids of high fertilizing quality that can harmlessly be stored or, functionally applied in relation to agricultural demand is a master challenge for the future, not only technologically. A deep transformation of societal beliefs and structures, economic processes and environmental understanding is equally imperative. The traditional pillars of sustainability will collapse under the tons of daily sludge production unless individually fortified and collectively integrated in a fundamental ecological, single-bottom-line concept of sustainability. Moving forward by meticulously matching, in all domains, practice with ecological theory and science will develop the synergy required for progress and success. The best management device reverses to ‘act globally, think locally’.
The United States National Biosolids Partnership: Improving Biosolids Management
Authors: DeMichele E. , Machno P. S. , Stone L. A.
Published: August 2018

The U.S. National Biosolids Partnership (NBP), an alliance of the U.S. Environmental Protection Agency (USEPA), National Association of Clean Water Agencies (NACWA) and Water Environment Federation (WEF), was formed in 1997 in response to public acceptance issues dealing with biosolids management. The United States Congress provides funding to assist public agencies to improve existing biosolids management programs to maintain/achieve public support. The key to a successful program is systematic management and an independent third party audit to assure organizations are managing biosolids to meet the requirements of an excellent biosolids management program. The NBP program utilizes the ISO 14001 Environmental Management System principles. The program has defined 17 components of excellent biosolids management and the independent third party audit program. One hundred organizations are participating in the program and 16 agencies have been “certified” though a third party audit. The smallest agency serves a community of 200 people and the largest treats over a billion gallons a day. Participants are benefiting through cost savings, efficiencies and better public trust.
The Australasian Biosolids Partnership and Public Perceptions
Authors: Gale A. J.
Published: August 2018

The Australian water industry recognized the need for the public, along with the managers of biosolids, to be better educated about the benefits and risks, along with management of these risks, for biosolids in Australia. Public perceptions and their influence on biosolids management were considered the most significant issue. After several years of discussions a national Biosolids Steering Group was established to develop a model for Australia and New Zealand. The result is the Australasian Biosolids Partnership (ABP). This paper reports on the drivers for the ABP, the differences to the NBP and SORP and the key components of the partnership. The approach to ownership and funding to ensure sustainable operation of the partnership are also discussed. The potential for wider application is explored. The paper also reports on the process in developing the ABP and gaining water industry buy-in.
Public acceptance and independent certification of biosolids in Canada
Authors: Hébert M.
Published: August 2018

Reclamation of biosolids through land application generally meets 2 key components of Sustainable Development: environment and economics. Unfortunately, societal acceptance is the weakest part of it, despite the scientific evidence that risks with biosolids are low or lower than with farm manures. Beside unacceptable odor problems in some areas - that have to be dealt with - there is a general pre-conception that biosolids are at risk. This pre-conception has to deal with modern urban culture, beliefs, values and taboos. Communication must therefore be an important part of every biosolids strategy. However, since some actors of the private and public sectors are not always trustworthy in the minds of the general public, it is necessary to have some kind of independent organization that states that a given biosolids is safe. Therefore, third-party standardization and certifications of biosolids appear to be a key component to Sustainable Development. However, it is important that the certification label is well known and trustworthy by stakeholders. Pro's and con's of the Canadian voluntary certification of biosolids will be presented.
Wastewater Sludge Management in the Russian Federation: the Current Status and Perspectives
Authors: Kalyuzhnyi S. V.
Published: August 2018

Above 80 million m3 of sludge are annually generated in the Russian Federation from a very huge domestic sewerage system and numerous municipal wastewater treatment plants. This paper discusses the status of sludge management in the country having more than one century experience in this field. Since Russia goes through a complicated period of transforming its economy with a focus on the expansion of private sector activity, this also includes reforms in the field of municipal waste water treatment and disposal. Current management practices are reviewed and the problems associated with them are evaluated including technological aspects as well as institutional issues, such as enforcement of legislation and problems with utilization/disposal. Perspectives for more sustainable sludge management are outlined and briefly discussed.
The Creation of a Regional Voice: The Care and Feeding of the Northwest Biosolids Management Association
Authors: Lono-Batura M. , Thompson D.
Published: August 2018

The biosolids producers in southwest Canada and the northwest United States have banded together to form a biosolids information network with the purpose of advancing the environmentally sound management of biosolids through education and information, regulations development and research and demonstration. This organization currently known as the Northwest Biosolids Management Association (NBMA) has grown from a gritty band of 14 sludge management visionaries to a fully incorporated non-profit association of over 200 members in both the private and public sectors. What spark ignited this conflagration of creativity? What calamity could possibly convince 200 relatively sober agencies to pony up a collective $200,000 American every year? What great cosmic bellows continues to force the airs of inspiration into the dry and desiccated souls of Biosolids managers across beautiful British Columbia and beyond? The answers lie in the modern day alchemy that is biosolids management. It is the inspiration gained from spinning gold out of something less aesthetically pleasing. It is the satisfaction in communicating to a mass audience the technical and counter intuitive science of residuals treatment. Creation and maintenance of a Biosolids information network is an essential tool in fostering the environmentally sound use of this extremely useful product.
Australia's National Biosolid Research Program - how it came about, and what has it discovered?
Authors: McLaughlin M.J. , Warne M. St.J. , Stevens D.P. , Whatmuff M.S. , Heemsbergen D. , Broos K. , Barry G. , Bell M.J. , Nash D. , Pritchard D. , Penney N.
Published: August 2018

The National Biosolids Research Program (NBRP) was established by the CSIRO Centre for Environmental Contaminants Research in 2002 in order to coordinate research relating to the benefits and risks of using biosolids for Australian agriculture. Prior to the establishment of the NBRP, research on biosolid use in agriculture had been concentrated in one state (New South Wales), with pockets of uncoordinated activity in other states. The NBRP is a coalition of seven research agencies around Australia, with support from several metropolitan and regional water authorities, and from several state environmental and natural resource management agencies. In terms of potential environmental risks, the NBRP initially concentrated on metals and focussed field experimentation on cadmium, copper and zinc. The research has subsequently moved onto examining potential risks from pathogens, pharmaceuticals, endocrine disrupting compounds and personal care products. As well as potential risks, the benefits of nutrients and organic matter in biosolids on crop growth are also being assessed, with various cropping systems around Australia being evaluated.
Management of Wastewater and Faecal Sludge in Southern Africa
Authors: Snyman Heidi G.
Published: August 2018

This paper deals with the trends, legislative framework and current sludge management practices in southern Africa. Recognising that a large percentage of the Southern African population is not serviced with full waterborne systems, a paper on the management of sludge in the region would not be complete without discussing the management of faecal sludge (FS) from on-site sanitation systems as well. The first half of the paper focuses on the management of wastewater sludge from waterborne sewage systems. The research papers from the region focus primarily on the impact of sludge application on land and agricultural use. The wastewater sludge disposal practices and legislative trends in South Africa are discussed in detail including an overview of the technologies that are used to stabilise, dewater and dry the wastewater sludge. The majority of plants in South Africa do not treat the sludge further than the traditional anaerobic digestion and activated sludge extended aeration. Final disposal methods are still dominated by on-site disposal methods including direct land application (dedicated land disposal) and stockpiling of the sludge on site. The second half of the paper focuses on the management of FS from on site sanitation systems. The FS, which is often contaminated with domestic waste, originating from these on-site sanitation systems requires responsible handling and disposal. The problems and challenges in FS management are highlighted as well as the recommended legislative trends.
The use of a national communication program to secure future biosolids outlets in Norway
Authors: Tornes O. , Nybruket S. , Haarr A.
Published: August 2018

Norway is among the leading countries in the world regarding the quantity and quality of treated sludge (biosolids) recycled to agriculture. However, for nearly 3 years ago the Norwegian Farmer's Union requested a scientific risk assessment of the use of biosolids for agricultural purposes. Considering the scepticism towards use of biosolids in agriculture in the neighbouring countries and possible impacts on domestic market mechanism, it cannot be taken for granted that agricultural outlets will continue to be the main recycling route in Norway in the future

To meet these challenges the Norwegian Water and Wastewater Association (NORVAR) has developed a national communication program in order to enhance mutual confidence and information transfer between the major stakeholders. The main objective of the program is to promote public acceptance and confidence in the utilitarian value of recycled biosolids. The program was implemented in 2005 as a 3 year program period and comprises objectives, strategies and measures respectively.

Experiences indicate that implementing the communication strategy will play an important role in securing biosolids recycling routes in Norway in the future. The paper will give a brief presentation of the program, experiences, results achieved, challenges and the way forward.
The First Two Years of Full-Scale Anaerobic Membrane Bioreactor (AnMBR) Operation Treating High-Strength Industrial Wastewater
Authors: Christian Scott , Grant Shannon , McCarthy Peter , Wilson Dwain , Mills Dale
Published: August 2018

The anaerobic membrane bioreactor (AnMBR) incorporates anaerobic digestion and membrane filtration in one process to form an innovative technology for treating high-strength industrial wastewater. The first AnMBR installation in North America, also known as the largest AnMBR installation in the world, was built at Ken's Foods in Massachusetts, USA.

Ken's Foods existing anaerobic process was upgraded to AnMBR in July 2008 to treat raw wastewater from the production of salad dressings and barbeque sauces. The system was converted to AnMBR due to lack of space, positive economics, and the ability to provide additional capacity for flow and organic load beyond the original anaerobic system design parameters.

This AnMBR system has a design influent flow rate of 475 m3/d with 39,000 mg/l COD, 18,000 mg/l BOD, and 12,000 mg/l TSS. The AnMBR system consistently produces a high quality effluent with non-detectable TSS concentrations and average COD and BOD concentrations of 210 and 20 mg/l, with removals of 99.4 and 99.9 percent, respectively. The AnMBR system provides superior performance and a very low rate of membrane fouling with the aid of biogas scour across the membrane surface.

The first 20 months of AnMBR operating expenses were reduced by 50 compared to the prior 12-month fiscal period due to increased system capacity, ability to treat wastewater with higher biomass, and elimination of the need to dewater and dispose of dewatered solids.
Remediation of model wastewater polluted with methyl parathion by reverse micelle entrapped peroxidase
Authors: Karim Zoheb , Husain Qayyum , Adnan Rohana , Akhtar Naseem
Published: August 2018

The peroxidase/reverse micelle (RM) system effectively catalyzed the oxidation reaction in cyclohexane, while peroxidase from bitter gourd in aqueous buffer exhibited low catalytic activity. The oxidation of methyl parathion (MPT) has been optimized with effects of pH in the water pools, concentration of peroxidase and degree of surfactant hydration (Wo). The peroxidase/RM system showed a strong pH dependency. Its optimum catalytic activity was obtained when the peroxidase/RM was prepared in a buffer of pH 3.0. The effect of different redox mediators on the peroxidase-catalyzed oxidation of MPT was investigated. MPT was slowly oxidized by the peroxidase/RM system while the addition of phenol as a redox mediator strongly enhanced the catalytic performance of the peroxidase/RM system. Hydrogen peroxide strongly inhibited the activity of peroxidase; when the H2O2 was present at more than 0.80 mM, the MPT transformation was significantly reduced.
A water efficiency rating system for land developments implementing integrated urban water management
Authors: Hunt J. , Anda M. , Mathew K. , Ho G.
Published: August 2018

Integrated Urban Water Management (IUWM) in land developments is becoming increasingly necessary in order to more efficiently utilise and manage water resources. Techniques including the control of stormwater runoff, increasing infiltration and providing opportunities for retention, treatment and reuse of both stormwater and wastewater, are well suited to being designed into the development rather than considered post-construction or not at all. There can be extensive capital investment by developers to implement IUWM which is often not returned in the land sales. This produces a disincentive for the developer unless the contribution is recognised and rewarded either financially or with appropriate marketing advantage. A system to rate land developments based upon IUWM has been developed that would quantifiably assess how effectively water resources would be utilised in a proposed land development. This assessment would provide a point of comparison between developments allowing property purchasers, developers, utilities and legislators to quickly compare how well the development performs in terms of IUWM, providing a mechanism for financial reward or recognition. This paper discusses the development of a model to quantifiably assess land developments for water efficient use and introduces a rating system with which land developments can be compared in terms of IUWM.
Development of evaluation methods to introduce a nanofiltration membrane process in drinking water treatment
Authors: Ohgai T. , Oguchi Y. , Ohno K. , Kamei T. , Magara Y. , Itoh M.
Published: August 2018

The objective of this study was to develop a new prediction method for evaluating performance of full-scale nanofiltration (NF) pilot plant by using small-scale pilot plants. Operating experiments using both multistage array pilot plant and two small-scale pilot plants in parallel had been conducted for about a year. From this experiment, it was revealed that data obtained from small-scale pilot plants could predict the performance of multistage pilot plant from the viewpoint of flux and rejection. In other words, both permeate water quantity of multistage pilot plant without noticeable fouling caused by aluminium from coagulant and permeate water quality of multistage pilot plant could be estimated.
Adsorptive fouling of a polypropylene microfiltration membrane with dissolved natural organic matter: do membranes possess an adsorption capacity?
Authors: Koh M. , Clark M.M. , Ishida K.P.
Published: August 2018

Rejection by membrane adsorption has been observed and widely reported. However, little is known about whether membranes possess an adsorption capacity. Experimental data showed that when a hydrophobic polypropylene (PP) microfilter was used to filter a large volume of particle-free surface water containing dissolved natural organic matter (NOM), later batches of microfiltration (MF) permeate caused more flux decline to a fresh 20K-Dalton polyethersulfone (PES) ultrafilter. This suggests that membranes can have an adsorption capacity for foulants. In this research, the gradual increase in absorbance of ultraviolet (UV) light by subsequent batches of MF permeate was observed, and supports the findings from previous studies, that only a small fraction of NOM causes membrane fouling. Attenuated total reflectance Fourier transform infrared spectrometry and energy dispersive spectroscopy of fouled PP and PES membranes suggests foulants containing amide, aromatic, ether, hydroxyl and silicate functional groups. Silicates appear to participate in membrane fouling, and its removal with the small fraction of fouling NOM can reduce the fouling potential of water. These data improve our understanding of membrane fouling by natural waters, and have implications for the design of membrane plants that filter natural waters.
Estimation of geographical variation of cancer risks in drinking water in Japan
Authors: Ohno K. , Kadota E. , Kondo Y. , Kamei T. , Magara Y.
Published: August 2018

The cancer risks posed by ten substances in raw and purified water were estimated for each municipality in Japan to compare risks between raw and purified water, and inter-municipality. Water concentrations were estimated by use of statistical data. Assigning cancer unit risks to each substance and applying the assumption of additive toxicological effects to multiple carcinogens, total cancer risks of the waters were estimated. As a result, the geometric means of total cancer risks in raw and purified water were 1.16×10−5 and 2.18×10−5, respectively. In raw water, the contribution ratio of arsenic to total cancer risk accounted for 97%. In purified water, that of four trihalomethanes (THMs) accounted for 54%. The increase of total cancer risks in purified water was due to THMs. In regard to the geographical variation, the relationship between population size and total cancer risks were investigated. The result was that there were higher cancer risks in the big cities with the population more than a million both in raw and purified water. One plausible reason for the higher risks in purified water in the big cities is a larger chlorination dose due to the huge water supply areas. The reason for the increase in raw water remained unclear.
Water quality deterioration after roof-top storage: implications on their maintenance and management
Authors: Wang G.S. , Chen H.W.
Published: August 2018

This study analyzed 323 water samples from 178 buildings in Taipei, Taichung and Kaoshiung cities to evaluate the water quality deterioration after roof-top storage. Water quality in distribution systems, household intake tanks (point-of-entry) and the tap (point-of-use) were compared. It was observed that chlorine decay is the major factor in deteriorating the water quality after storage. Relatively high water temperature and the presence of higher organic/inorganic impurities are the main reasons that cause the large chlorine decay in Kaoshiung. Most of the microbial regrowth was observed in the samples with chlorine residuals less than 0.2 mg/L, indicating that 0.2 mg/L of chlorine residual is a suitable criterion to prevent the microbial contamination. After roof-top storage, the chlorine residual, total dissolved solids and turbidity were decreased; however, total bacteria counts and pH were increased. For better management of household storage systems, some preventive actions has been taken to improve the water quality at point-of-use.
Occurrence of 1,4-dioxane and MTBE in drinking water sources in Japan
Authors: Simazaki D. , Asami M. , Nishimura T. , Kunikane S. , Aizawa T. , Magara Y.
Published: August 2018

Nationwide surveys of 1,4-dioxane and methyl-t-butyl ether (MTBE) levels in raw water used for the drinking water supply were conducted at 91 water treatment plants in Japan in 2001 and 2002, prior to the revision of the drinking water quality standards. 1,4-dioxane was widely and continuously detected in raw water samples and its occurrence was more frequent and its concentrations higher in groundwater than in surface water. However, its maximum concentration in raw water was much lower than its new standard value (50 μg/L), which was determined as a level of 10−5 excessive cancer risk to humans. Trace levels of MTBE were also detected in several surface water samples.
Identification of 2-MIB and geosmin producers in Feng-Shen reservoir in south Taiwan
Authors: Tung S.-C. , Lin T.-F. , Tseng I.-C. , Lin H.-M.
Published: August 2018

Musty and earthy odor are present in the source water of Feng-Shen waterworks (FSW) in south Taiwan all year round. Although 2-methylisoborneol (2-MIB) and geosmin are responsible for the musty and earthy odor, respectively, the possible odor producers remained unknown. In this study, actinomycetes that produce 2-MIB and geosmin were studied. Based on the 16S rDNA sequence, three species were identified after comparison with the GenBank database at the NCBI. The three species are Streptomyces malaysiensis as a 2-MIB and geosmin producer, Streptomyces caelestis as a 2-MIB producer, and Streptomyces roseoflavus as a geosmin producer. For S. malaysiensis and S. caelestis, the production of MIB and/or geosmin was increased with incubation temperature (20–30 °C) in starch–glutamate broth medium. The optimal MIB, geosmin and biomass occurred at 30 °C. The maximal geosmin/biomass (G/B) and/or MIB/biomass (M/B) also occurred at 30 °C, and sporulating cultures contained more geosmin and/or MIB than nonsporulatig cultures.
Oxidation of geosmin and MIB in water using O3/H2O2: kinetic evaluation
Authors: Park G. , Yu M. , Koo J.-Y. , Joe W.H. , Kim H.
Published: August 2018

Tastes and odors (T&Os) of drinking water have been a major issue for water utilities in Korea, due to the ever-increasing consumers' demand on drinking water quality and complaints on T&Os. Among the T&Os causing chemicals in water, the most common and problematic ones are geosmin and 2-MIB, which are produced by blue–green algae and actinomycetes. The odors of the chemicals are characterized earthy and musty/camphorous. Since the reported odor thresholds of geosmin and 2-MIB are as low as 4.0 and 8.5 ng/L, respectively, they are not readily removed by conventional water treatment processes or by simple ozonation. Therefore, oxidation of the chemicals using hydrogen peroxide (H2O2) along with ozone (O3) has been tried as an alternative. In this study, kinetics of geosmin and 2-MIB ozonation at different initial O3 doses, H2O2/O3 ratios, and temperatures were evaluated. In short, a significant promotion of geosmin and 2-MIB ozonation rate was observed at higher H2O2/O3 ratios at lower temperature; therefore, geosmin and 2-MIB could be successfully removed from water. However, when an ozonation process is designed ozone residual should be considered for satisfactory disinfection; H2O2 addition may promote O3 decomposition and may have an adverse effect on disinfection. Therefore, determination of H2O2 and O3 doses should be carefully made for achieving both disinfection and T&Os removal.
Identification and prioritization of performancelimiting factors for water treatment plantoptimization in Korea
Authors: Park N.-S. , Kim J.-H. , Bae C.-H. , Moon Y.-T. , Ahn H.-W.
Published: August 2018

Performance limiting factors (PLFs) derived from 161 drinking water treatment plants (DWTPs), assessed by the International Technical Diagnosis and Assistance Center, were analyzed and evaluated in this study. In order to conduct research, 161 DWTPs were divided into five categories depending on their capacity, and into twelve groups according to processes and facilities. From the results of analysis, PLFs and their distribution ratio derived from each category were significantly different. Filtration was the most important performance limiting factor in all DWTPs of five categories, and PLFs in filtration were backwashing velocity, media configuration, bed depth, and formation of mud-ball. The PLFs in coagulation–flocculation process were found to be coagulant dose, mixing intensity, mechanical problems, and others in the order of frequency of occurrence. Also, insufficient disinfection ability, is resulting from insufficient hydraulic detention time, improper chlorine dose and injection point, is the most significant among PLFs in a clear well. In the case of sedimentation, inappropriate baffle structure and excessive upward velocity were PLFs. In addition, the results showed that high turbid water and low alkalinity in rainy season, ferric and manganese ions, and ammonia nitrogen have contributed significantly to the performance of DWTPs.
Advanced oxidation of methyl tert-butyl ether (MTBE) by UV/TiO2 and H2O2-UV/TiO2 processes
Authors: Hung C.-H.
Published: August 2018

This study investigated photocatalysis of MTBE via both UV/TiO2 and H2O2-UV/TiO2 processes. Several experimental parameters including pH level, H2O2 concentration, TiO2 dosage and light intensity were investigated. The experimental results demonstrated the degradation of MTBE following a pseudo first-order reaction in both reaction systems. Faster degradation rates were observed in alkaline solution for the UV/TiO2 system, but for the H2O2-UV/TiO2 system, faster degradation rates were detected in acidic solution. More dosage of TiO2 and irradiated light intensity were beneficial for the photocatalysis of MTBE. However, a peak reaction rate was observed at a TiO2 concentration of about 500 mg/L. The experimental results also indicated that the degradation rate of MTBE was enhanced by the addition of H2O2. H2O2 could be a more efficient electron acceptor than oxygen for retarding recombination of electron–hole pairs. The degradation rate in the H2O2-UV/TiO2 system was about 2.8 times faster than that in the UV/TiO2 system for solution pH below 5, and the rate increased 30% for solution pH above 6. In addition, it is observed that the reaction rate of MTBE increased quickly with H2O2 concentration at low H2O2 dosages, but the rate was independent of H2O2 dosage when adding too much H2O2.
Photocatalytic oxidation of aquatic humic substances using TiO2/UV in a rotating photoreactor
Authors: Han I. , Shin J.W. , Kim H.C.
Published: August 2018

Applicability of a rotating reactor for photocatalytic oxidation of humic substances extracted from the Han River in Seoul, Korea (Han-HS) was investigated. Because air blowing for complete dispersion of TiO2 photocatalysts could inhibit ultraviolet (UV)-irradiation between UV lamps and photocatalysts by air bubbles, a rotating photocatalytic reactor with four baffles was used for better UV-irradiation in this study. Han-HS was extracted and treated with UV-irradiation. Because Han-HS is different from other commercial humic materials (e.g. Aldrich Humic acid and International Humic Substance Society NOM), structural spectroscopic analyses were conducted by FT-IR and 13C-NMR. Immobilized TiO2 coated on hollow beads was used to separate and recover the photocatalyst. During two hours of UV-irradiation, absorbance at 254 nm (UV254) and total organic carbon (TOC) content were monitored. Photocatalytic oxidation efficiencies of different wavelengths of UV lamps (254 nm and 352 nm) were also compared and raw and pre-chlorinated waters of the Han River were used to evaluate the applicability for water treatment.
Photocatalytic hybrid system in degradation of herbicide (metsulfuron–methyl)
Authors: Nathaporn A. , Shon H.K. , Vigneswaran S. , Ngo H.H.
Published: August 2018

Photocatalytic oxidation is becoming an emerging technology in water and wastewater treatment. Photocatalysis often leads to complete degradation of organic pollutants without any need for chemicals. In this study, the removal of the herbicide metsulfuron–methyl (MM) by photocatalysis was studied. Titanium dioxide (TiO2) was used as a catalyst in a UV reactor equipped with three lamps each with 8 watts of power. The total surface of UV lamps was 537 cm2. The capacity of the photocatalytic reactor was 1.5 L. The effects of parameters such as pH and TiO2 dose on the removal of MM were studied. The combined system of the photocatalytic reactor with powder activated carbon (PAC) adsorption was also investigated. The results indicate that the use of PAC reduced the TiO2 dose and led to very high removal efficiency. A very small dose of 0.05 g/L PAC reduced TiO2 requirement from 2 g/L to less than 0.5 g/L. A detailed molecular size distribution measurement made using high performance size exclusion chromatography (HPSEC) showed that TiO2 can degrade the MM to a small molecular weight compound of 50 daltons within a detention time of 40 minutes. This hybrid system was found to be technically and economically more efficient than the other processes used to remove herbicides and pesticides.
New systematic data utilization for monitoring surveys in Lake Biwa
Authors: Kitpati S. , Fujii S. , Tanaka S.
Published: August 2018

Lake monitoring surveys data are vital and have been being accumulated for every lake. However data itself, without effective data management and interpretation, cannot be used to tell the story or history of the lake. Therefore, this project aims to develop a new water quality database system for a lake with systematical functions to utilize such data effectively and to satisfy both general public users and specialists. Lake Biwa was chosen as the target lake, where long-term monitoring data were available for almost one hundred years. A relational database application, Access 2002, with the help of Macro functions and VBA (Visual Basic for Applications) was introduced to organize all of the data. With the systematical storing of data, valuable data could be easily accessed, filtered and powerfully utilized for researchers own interests. The filtered data can be written into basic documents (spreadsheet or text files), provided for outside requests, and again used for further basic and advanced analysis by a reading back process. The system supports multiple users, especially public users by providing user interface system and visualized result displays. The final outcomes from this systematic data utilization can be fruitfully used as the guideline for effective monitoring management program of lake water quality.
Optimal operations for groundwater denitrification of drinking water using heterotrophic biological denitrification process
Authors: Hung C.-H. , Tsai K.-H. , Su Y.-K. , Liang C.-M. , Su M.-H. , Horng S.-J.
Published: August 2018

Due to the extensive application of artificial nitrogen-based fertilizers on land, groundwater from the central part of Taiwan faces problems of increasing concentrations of nitrate, which were measured to be well above 30 mg/L all year round. For meeting the 10 mg/L nitrate standard, optimal operations for a heterotrophic denitrification pilot plant designed for drinking water treatment was investigated. Ethanol and phosphate were added for bacteria growing on anthracite to convert nitrate to nitrogen gas. Results showed that presence of high dissolved oxygen (around 4 mg/L) in the source water did not have a significantly negative effect on nitrogen removal. When operated under a C/N ratio of 1.88, which was recommended in the literature, nitrate removal efficiency was measured to be around 70%, sometimes up to 90%. However, the reactor often underwent severe clogging problems. When operated under C/N ratio of 1.0, denitrification efficiency decreased significantly to 30%. Finally, when operated under C/N ratio of 1.5, the nitrate content of the influent was almost completely reduced at the first one-third part of the bioreactor with an overall removal efficiency of 89–91%. Another advantage for operating with a C/N ratio of 1.5 is that only one-third of the biosolids was produced compared to a C/N value of 1.88.
Pilot study on the effect of removing anion-surfactant by general coagulation-settlement process
Authors: Cui F.-Y. , Ren G. , Zuo J.-L.
Published: August 2018

Due to the overseas application of anion-surfactant (LAS) in civil and industrial use, water pollution problem becomes more increasingly serious. It is necessary to study the effect of removing anion-surfactant by general water supply process. The coagulant Al2(SO4)3, PAC, FeCl3, PFS and non-ion PAM were adopted in the experiment. Results indicated that coagulation could remove about 20–40% of LAS in water, and there was a positive correlation between dosage and elimination effects before the maximum removal effect was reached. However, at different coagulations, the maximum elimination and the corresponding dosage were quite different. When the water quality condition was the same, iron-coagulation was much better in removing turbidity, organisms and LAS than aluminium-coagulation. A correlation between the amount of LAS and organism removed was found in our test, which was much closer than between LAS and turbidity. This indicated most LAS was combined with other organic matters in water. That was to say the removal of LAS and other organic matter was concordant, which was significant to the removal of LAS. Water temperature and pH has much effluence on the wiping off of LAS. Both lower pH and higher temperature are propitious to remove LAS.
Effect of tapering on the break-up and reformation of flocs formed using hydrolyzing coagulants
Authors: Yukselen M.A. , O'Halloran K.R. , Gregory J.
Published: August 2018

The effect of tapered-shear (diminishing velocity gradient) flocculation on the formation, breakage and reformation of flocs using aluminium sulphate and an anionic polymer were evaluated. An on-line continuous optical monitoring technique was used for this purpose. Two different mean shear rates, G=60s−1 and G=100s−1 were tried in the slow stirring stage of the experiments. For the mean G=60 sec−1, sample was stirred at 400 rpm (G=518 sec−1) for 10 seconds then the stirring speed was reduced to 100 rpm (G=60 s−1) and held at this value for the required time (9 minutes). In the other trial, slow stirring speeds of 130 rpm, 100 rpm and 70 rpm and 150 rpm, 100 rpm and 50 rpm for 3 minutes each were used. After slow stirring, the speed increased to 400 rpm (G=518 s−1) for 10 seconds and then reduced back to appropriate slow stirring speed as stated above. A similar approach was applied for mean G=100 s−1. For continuous tests, a laboratory scale set-up was constructed as a tapered flocculation system that consists of three chambers. Flocs formation in the first and third chambers were monitored and compared. Larger flocs that have higher reformation rate were produced with tapered flocculation.
Control of biofilm growth in drinking water distribution system by biodegradable carbon and disinfectant residuals
Authors: Zhang X.-J. , Lu W.
Published: August 2018

Biofilm growth in drinking water distribution systems was studied in an annular reactor system which was designed to model the hydraulic conditions in water mains. Experiments were performed with chlorine-free water as well as with different disinfectant (chlorine or chloramine) residuals and different AOC concentrations added to the reactor influent to examine the effect of disinfectant residuals and AOC concentrations on biofilm accumulation and planktonic cell numbers. The dynamic parameters of bacteria growth were calculated in water with different disinfectant (chlorine or chloramine) and the results indicated that monochloramine may be more effective than free chlorine for control of biofilm accumulation.
Biological filtration for the removal of algal metabolites from drinking water
Authors: Ho L. , Hoefel D. , Aunkofer W. , Meyn T. , Keegan A. , Brookes J. , Saint C. , Newcombe G.
Published: August 2018

Biological sand filters were assessed for their ability to remove geosmin, 2-methylisoborneol (MIB) and microcystin-LR. Microcystin-LR was the most readily degradable metabolite with a maximum lag period of only 5 days before it was undetected in the filter effluent. Geosmin and MIB were difficult to degrade, with a period in excess of 75 days before greater than 95% removal was achieved. A microcystin-degrading gene was detected in the biofilm from one of the filters, confirming that the biofilm possessed the ability to degrade microcystin. A Sphingomonas sp. was identified as a potential geosmin degrader based on denaturing gradient gel electrophoresis (DGGE) analysis. DGGE analysis revealed a more complex bacterial community during the degradation of MIB, suggesting that more than one bacterium may be responsible for its degradation.
Assimilable organic carbon (AOC) originating from picophytoplankton in drinking water
Authors: Okuda T. , Nishijima W. , Okada M.
Published: August 2018

The removal efficiency of conventional drinking water for picophytoplankton and the contribution of picophytoplankton to AOC were investigated in this research. The removal ratio during coagulation–sedimentation step was determined by jar test using PAC (poly-aluminium chloride). Lower coagulation pH showed better picophytoplankton removal in coagulation–sedimentation. The optimum coagulant dosage for picophytoplankton was twice or more than that for turbidity. The removal efficiency of picophytoplankton was 44–60% at lowest pH in water quality standard (5.8) and at an optimum coagulant dosage for turbidity. The removal ratio of picophytoplankton in rapid sand filtration was determined by pilot scale column experiments with sand and anthracite. The average removal percentage was 16.3% without PAC addition and chlorination before sand filtration; on the other hand it was 51.5% with PAC and chlorination. AOC increased by the chlorination of picoplankton including 6,800 cells/L of picophytoplankton was 21 μg-acetateC/L at 0.1 mg/L of residual free chlorine. The AOC was increased by the increase of residual chlorine concentration, and leveled off at 0.3 mg-Cl/L. From the result, the AOC originating from picoplankton (maximum AOC from picophytoplankton) could increase up to 155 μg-acetateC/L in this reservoir. It indicates that the removal of picoplankton (picophytoplankton) in drinking water treatment process is important from the viewpoint of AOC control.
Effect of chlorination on estrogenicity in chlorinated treated effluent
Authors: Hu J.Y. , Chen X. , Jin X. , Tan X.L.
Published: August 2018

Effluents from sewage treatment plants can be discharged into rivers with estrogenic contaminants at levels sufficient to induce adverse reproductive and fertility developments in humans and wildlife. Of great concern in recent years are the estrogenic activities of chlorinated by-products (CBPs) in effluents. Simplified cell proliferation tests using the human estrogen receptor-positive MCF-7 ATCC breast cancer cells (E-SCREEN) were performed to investigate the influence of chlorination on the estrogenicity in effluents. It was found that the increase of chlorine dosages from 0 mg/L to 4 mg/L led to the decrease of total content of estrogenic activity: the 17ß-estradiol equivalent concentration (EEQ) from 22.40 to 8.35 ng/L. However, the increase of contact time from 10–30 minutes increased EEQ from 14.04 to 29.97 ng/L. Furthermore, increasing TOC level using humic acid from 5 mg/L to 15 mg/L in effluents correspondingly resulted in an increase of EEQ from 19.69–27.20 ng/L; it was thus confirmed that chlorination of humic acid could produce estrogenic by-products.
Keeping residual chlorine and decreasing unpleasant odor caused by disinfection of tap water
Authors: Kitazawa H.
Published: August 2018

Keeping residual chlorine at a certain level in tap water is effective not only in improving sanitary conditions but also in suppressing the regrowth of microorganisms and preventing the formation of biofilms on the internal surface of distribution pipelines. However, in our recent survey about customer satisfaction, over 50% of the customers were not satisfied with tap water for drinking. One of the main reasons for the dissatisfaction was the odor or taste caused by the disinfection process. We therefore investigated the behavior of residual chlorine in the water distribution network by estimating the chlorine decay coefficients, and discussed measures to decrease the unpleasant odor while maintaining the effect of disinfection. The effective measures are shortening of retention time, replacement of aged pipes, corrosion control of distribution and service pipes, removal of organic substances in water, additional chlorination at water-supply stations, and improvement in water supply facilities with receiving tanks. By adopting these measures, and setting the target value of residual chlorine at representative water taps, we successfully controlled residual chlorine at the outlets of purification plants or water-supply stations by application of the decay coefficient of chlorine in each water distribution system.