bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of natural organic compounds on the removal of organic carbon in coagulation and flocculation processes
Authors: Jegatheesan V. , Lamsal P.R. , Visvanathan C. , Ngo H.H. , Shu L. 
Published: May 2018

Natural organic matter (NOM) in water contains organic compounds that are both hydrophobic and hydrophilic with a wide range of molecular weights. It is composed of non-homogeneous organic compounds such as humic substances, amino acids, sugars, aliphatic and aromatic acids, and other chemical synthetic organic matters. NOM in water is a major concern not only because of its contribution to the formation of disinfection by-products (DBPs) and taste and odor, but also its influence on the demand for coagulants and disinfectants, the removal efficiency of water treatment processes, etc. This research aims at identifying the influence of NOM in coagulation and flocculation processes in order to optimize the coagulation and flocculation conditions. In this study, pretreated pond water was used as the source water. It was observed from the experimental results that:The optimum pH for coagulation to remove NOM is around 7.The optimum alum dose at this pH can vary from 125-1,225 mgl-1 when the TOC is increased from 4 to 25 mgl-1.The presence of secondary compounds such as Ca2+, Mg2+ divalent cations had no significant effect on the removal of organic matter.The presence of clay increased the organic removal by 15%.The organic compound with higher molecular weight has higher removal affinity in coagulation process.Floc size and settling velocity of floc and sludge production all increased with the increase in NOM concentration. From the results of Capillary Suction Time (CST) tests, the floc formed with lower TOC readily released the water to make the dewatering process easier.The organic removal efficiency was significantly different for natural water containing non-homogeneous organic compounds compared to the synthetic water containing humic acid only (homogeneous organic matter).
For example, the NOM removal efficiency was 80% for the synthetic water containing humic acid with TOC of 7 mgl-1 at pH 7; but the NOM removal for the pretreated pond water was 60%.
Management of large water resource systems
Authors: Mckenzie R.S. , van Rooyen P.G. 
Published: May 2018

South Africa has one of the most complicated and integrated water resource systems in the world involving numerous interlinked river systems and major interbasin transfer schemes. The management of the various schemes has become a key issue over the past 15 years resulting in the development of sophisticated systems models which are now used to analyse and operate all of the country's major schemes. The models have been developed through a partnership between the Department of Water Affairs and Forestry in association with several of the country's consultants specialising in this area of expertise. The models have now reached a stage where they are considered to be both practical and sufficiently robust to use in other parts of the world.
Australia and South Africa are quite similar in many respects with regards to the water resources and climate. Both countries share the same problem of large arid or semi-arid areas together with areas where the local water resources are insufficient to meet the existing or predicted future demands. Environmental considerations are also of major importance in both countries which in turn necessitates the effective use of the available resources before any new resources can be developed.
In order to use the available water effectively much effort has been placed on various aspects of Water Demand Management in order to reduce leakage and excessive consumer use. It is also necessary, however, to ensure that the raw water resources are managed in an efficient and practical manner - something that is often easier said than done.
This paper provides general details of the system analysis techniques that have been pioneered in South Africa and discusses the most recent developments that can be used to assist water resource managers in the analysis and planning of their water resource systems.
Management strategies for optimum meter selection and replacement
Authors: Arregui F. , Cabrera E. , Cobacho R. , Palau V. 
Published: May 2018

There are two main decisions faced by utility managers regarding meters in an undertaking: which meter to instal and when to replace it. Traditionally the criteria used to make these decisions have been arbitrary and often imposed by third parties regardless of the situation of the individual undertakings. This paper presents “Comparative billing analysis”, a methodology to analyse meter performance within the undertaking, as a means to support decision making in water meter management.
The main difference between the comparative billing analysis and previous methodologies resides in the use of the commercial billing database that most undertakings have these days. By analysing existing data with a systematic approach, it is possible to determine which kind of domestic meter is most appropriate for the utility. This method turns out to be as reliable as previous ones, but much more efficient in the use of economic and human resources.
Investigation into the implementation of chloramination at Sedibeng Water
Authors: Basson N. , Traut D. , Titus G. , vd Walt C. , Haarhoff J. 
Published: May 2018

The Balkfontein and Virginia plants of Sedibeng Water, situated in the Free State Province of South Africa, treat water for potable purposes. Chlorine is used as disinfectant at both plants. Low levels of free chlorine measured in the water supplied from some reservoirs, logistics and costs, related to the application of chlorination at various points in the distribution system, were the main thrusts for an investigation into the use of chloramination as an alternative means of disinfection.
The so-called contact time (CT)-approach from the United States Environmental Protection Agency was applied for the evaluation of disinfection efficiency. The distribution system was modelled by using a hydraulic computer system. Decay rates for both chlorine and monochloramine - a vital parameter for eventual determination of the amount of chlorine and ammonia to be dosed - were determined. The levels of disinfectant in the water at a specific location could be predicted by using the decay values.
The main findings of this investigation are that chloramination is an attractive and cost-effective alternative for conventional chlorination for providing quality assurance to all. It is estimated that the capital layout will be recovered within one year of operation of the ammoniation system.
Canal de Isabel II solution for remote control over small and scattered facilities
Authors: Zubizarreta J.I. 
Published: May 2018

A description is given of the solution used by the Canal de Isabel II (CYII) in response to the need to monitor 500 small facilities scattered throughout a region covering a surface area of 8,000 km2.
The system design, and the hardware and software, have been developed entirely by the CYII using easy-maintenance criteria. As most of the facilities lack an electricity supply, alternative methods are used. Energy consumption is greatly reduced by intermittent operation. Communication is by radio, making use of the company’s own networks.
The theoretical bases of the intermittent operation, the overall characteristics and the experience obtained are all explained through an approach that focuses upon the part of the system that is installed in situ.
Marketing a technical business
Authors: Karbowiak P. 
Published: May 2018

Until recently most water utilities have operated as a public service. The market is still predominantly a natural monopoly. The significant infrastructure requirements militate against service duplication and competition. Generally customers do not have the option of changing service providers. With the arrival of competition policy, water utilities have initiated some customer service programmes. However, the driver for this change has been the reporting requirements of the regulator rather than customer focused imperatives.
However, there are benefits for water service companies to conduct professional market research focused on customer satisfaction. This paper reviews the concepts of market customer satisfaction analysis. It discusses the shortfalls of generic methodologies which focus on the performance of the service provider rather than the needs and expectations of the customer. The application of Benchmarking or Best Practice, is also reviewed within this context.
A conclusion of this paper is that the application of focused, professional customer satisfaction analysis is an effective quality management tool and leads to a better understanding of water services customers’ needs and expectations. The outcome is more effective application of customer service resources, enhanced community perceptions and the achievement of higher levels of customer satisfaction.
Management strategy of emergencies and events in the monitoring of water distribution in Paris
Authors: Montiel F. , Coutelan J. 
Published: May 2018

For water distributors, management of emergencies and the follow-up of events in real time represent an essential aspect of their work. Proper management of this information makes for optimization of its use and enables one to avoid a large number of problems regarding water supply thanks to improved reactivity and more precisely-focused action.
Since 1992, Sagep (Société Anonyme de Gestion de l’Eau de Paris) to whom the City of Paris has entrusted responsibility for its water supply, has equipped itself with a computerized real-time monitoring system. Initially, this system processed 5,000 pieces of real-time information, which permitted monitoring of the 1,600 km of drinking water pipes and made possible distribution of the 650,000 m3 of drinking water consumed daily by Parisians.
In 1996, given the enormous progress achieved with regard to information systems and measuring devices installed in the pipe networks, the Scada at Sagep was modernized. This made possible the integration of the fresh information necessitated by developments in the supply system of the City of Paris, plant renovation, new sensors, the traceability of events and water quality follow-up.
These developments led to the integration and management of 17,500 pieces of real-time information, over three-quarters of which are made up of emergencies or events. It seems clear that it is impossible to manage such a mass of real-time information in the absence of a rigorous processing strategy. To exploit this set of data in optimal fashion, Sagep has developed a system of management of emergencies based on three thrusts: identification, qualification and processing.
Efficiency in water planning and management (an implementation experience)
Authors: Vojdani F. 
Published: May 2018

Water is a primary factor in sustainable development; it may also be considered the most important component of economic and political power in contemporary world. Countries like Iran, which are located in arid and semi-arid regions of the world, since they are in permanent water crisis condition, must react by concentrating on research, pure studies and striving as far as possible to utilize water as optimally and manage water consumption. Lack of precipitation, inadequate infrastructure for collection, storage and recycling of water and above all, lack of public awareness regarding such issues as standard consumption patterns, force all countries like Iran to adopt strategic management policies and techniques toward such issues as water resources, maintaining and upgrading water quality, recharging of water resources and also other concepts, such as, “defined consumption”.
Although Tehran province enjoys having various surface and underground water resources, and also so-called scattered and undirected water resources such as Qanats, springs, treated waste water, etc., adding all these resources together, it still cannot quench its thirst. Average annual temperature and rainfall, and also explosive rate of population migration to the province, are main reasons of existing and widening gap between supply and demand. It seems the only alternative left is to capitalize and utilize various techniques to reduce consumption, otherwise Tehran will face a continuous and uninterrupted water crisis. Proposed strategic management viewpoint should also cover other areas such as supply, transfer, treatment, storage and also distribution and consumption. For each of above topics, special operational management should be considered and executed. Although, there were many reasons behind the recent water crisis, one of the main reasons was uncoordination among various management divisions which ended up in rationing. Tehran's water crisis was handled successfully by utilizing various strategic management techniques, but in order to prevent such crisis repeating itself, we must adopt long-term strategic policies and demand management, also various techniques of efficient use of water.
Assessment of real losses in potable water distribution systems: some recent developments
Authors: McKenzie R. , Seago C. 
Published: May 2018

Considerable progress has been made over the past 10 years in the assessment and benchmarking of real losses in potable water distribution systems. Most of the advances have been based on the burst and background estimate (BABE) methodology, which was first developed in the mid-1990s by the UK water industry and has since been widely accepted and used in many parts of the world. Since the original BABE methodology was developed, several other key concepts have been added to the evergrowing list of water demand management tools. In particular, the infrastructure leakage index (ILI) and unavoidable annual real losses (UARL) introduced by A. Lambert, and the fixed area variable area discharge (FAVAD) theory by J. May, are now recognised as key “tools of the trade” in any water demand management assessment.
One of the first main developments where the above-mentioned concepts were applied in practice to benchmark leakage was in South Africa, where the local Water Research Commission supported the production of the BENCHLEAK Model. This was basically the first comprehensive model to assess real losses in potable water distribution systems using the UARL and ILI concepts. The model was developed by one of the authors together with A. Lambert, and was soon followed by similar developments in Australia (BENCHLOSS) and New Zealand (BENCHLOSSNZ). Both models incorporated additions and enhancements to the original South African model, and were tailored to suit the local conditions in line with the clients' requirements.
Similar developments took place in parallel by various leakage specialists, most notably in Brazil, Malaysia and Cyprus, to mention just a few of the similar initiatives. Each time a new model was developed, certain improvements were made and the “science” of leakage management and benchmarking was enhanced.
Through the use of the different models and from discussions with various researchers from around the world, it has become clear that there is a genuine need for such models, and they are being readily accepted by clients in most areas. The discussions have also raised many questions concerning the derivation of the terms used to calculate the UARL and the ILI, and, to address these concerns a specialist group was created through the IWA to investigate the various issues.
This paper will highlight the progress that has been made to date with regard to the key issues that have been raised by the task-team members, and recommendations based on the feedback that has been received from around the world. The paper will also present some of the results that have been obtained from different parts of the world to highlight both the progress and the problems associated with the assessment of real losses. The paper will conclude with a short description of several new models that have been developed and are in use, which demonstrate the latest improvements to an ongoing process to assess and benchmark real losses in water distribution systems.
Needs and barriers in technical regulations and standards for the efficient use of water: situation in Portugal and Brazil
Authors: Almeida M. do C. , Vieira P. , Ribeiro R. , Andrade M. 
Published: May 2018

Appropriate legislation, technical regulations and standards are essential to put into practice water-efficient technologies, procedures and products, both to promote the implementation and to avoid eventual barriers in the application of the adequate measures. In Portugal as in Brazil, efficient use of water and the reduction of water waste are important environmental goals. In the former, the National Program for the Efficient Use of Water for the urban, agricultural and industrial sectors is the base document for this purpose. In the latter, the National Program to Prevent the Waste of Water, for the urban sector, has been in action since 1997.
The purpose of the paper is to present a brief overview of the current situation in terms of regulations and standards, highlighting the needs and some barriers, having as reference the situation in Portugal and Brazil, and the measures intended to be applied in the respective programs.
Ocean Disposal Legislation in the United States†
Authors: Guarino C F , Townsend S 
Published: May 2018

A review of legislation and implementing regulations pertaining to disposal of sludge at sea in the United States was performed. The experiences under the law of two major municipalities that have employed diposal at sea were studied and compared.
Major changes are shown to have taken place in the Federal approach to regulating ocean disposal. Ocean dumping regulations are shown to have produced very different current situations for two major municipalities. The City of Philadelphia, operating under rigid federal policies, successfully ended ocean disposal over a year before the statutory deadline by implementing carefully managed, but costly, land-based sludge disposal alternatives. The City of New York, in contrast, still uses the ocean for sludge disposal and has recently won a ruling in Federal District Court which may allow continued ocean disposal for many years beyond the December 31, 1981 end-date proscribed by the law.
†This paper should be included in Theme 1A - Legislation.
Sludge Disposal to Sea in France†
Authors: Aubert M , Gauthier M J , Aubert J 
Published: May 2018

After a general review on the nature of the polluting elements in domestic sewages and on the relationships between bacteria and particulates in sludges, a mathematical formulation of the dynamics of suspended matter in the sea is presented. On the basis of these data, the different types of treatment of wastewaters and sludges used in France are described and discussed.
†This paper should be included in Theme 3 - Case Histories.
Biological Nitrification in an Up Flow Fixed Bed Reactor (UFBR)
Authors: Faup G-M , Leprince A , Pannier M 
Published: May 2018

This paper describes a kinetic model for ammonification and nitrification in an upflow fixed bed reactor (UFBR) with direct injection of air into the support material. Modeling has been based on the computation of active biomass concentration along the reactor. The tests, which extended over a period of one year and have been applied to municipal sewage after conventional treatment using activated sludge, have shown that the filtration rate is the most important factor as regards both the overall quantity of biomass found in the system and the distribution of this biomass within the reactor. The optimum quantity of biomass is obtained with a filtration rate of around 5 m3.m2.hr. Under these conditions, it is then possible to reach active biomass concentrations 8 to 9 times higher than the ones found in conventional processes based on the use of nitrifying activated sludge.
It is also clearly evidenced that ammonification will, in most cases, be incomplete and this will limit the efficiency of the overall reaction Total N → NO3−.
Other parameters also greatly influence the process : among these parameters, the influence of the ratio air process rate/influent rate has been the subject of special examination.
Some Perspectives in the Modelling of Biological Treatment of Wastewaters
Authors: James A 
Published: May 2018

This paper reviews some recent developments in the modelling of the biological treatment of wastewaters with particular reference to the activated sludge process. The bacterial kinetics of completely-mixed reactors are discussed emphasising the need to have a variable yield. Modelling complications of variable yields are noted in particular those caused by de-coupling growth and substrate utilization. Other methods of solution are considered including relating the yield to the sludge age.
Modelling developments in fixed-film reactors are briefly examined, comparing the refinement in the chemical/physical description with the lack of refinement in the ecological representation.
The aims of modelling are reviewed and some fruitful areas in operational models and computer-aided-design are identified.
Studies on Oxygen Transfer Models
Authors: Matsuo T , Hirayama K 
Published: May 2018

The liquid film coefficient of the oxygen transfer at air-water surfaces is dependent on turbulence characteristics of the flow. There are two methods for evaluating the liquid film coefficient with relation to turbulence; One is based on the root mean square velocity fluctuation and the larger scale movement and the other is based on the energy dissipation rate and the smaller scale movement.
Conclusions obtained from some experimental and dimensional analyses imply that, for the mass transfer mechanism at the air-water surfaces, larger scale turbulent motion is dominated over smaller scale eddies represented by Kolmogoroff's micro-scale.
Land Extensive Processes for Wastewater Treatment and Disposal – A Perspective
Authors: Parker C D 
Published: May 2018

Land extensive processes for treatment of wastewater have been used for pollution control for over a hundred years.
Recently more sophisticated demands related to protection of the environment, energy considerations, and costs related to conventional biological and physico-chemical processes, have been responsible for great scientific endeavour in the understanding, assessment of purification mechanisms, behaviour and performance, and the costs, of land extensive systems of treatment by lagoons and by land irrigation.
Favourable characteristics of these land extensive processes have led to their widespread application in suitable sparsely populated areas particularly in developing countries.
The paper details the processes, the factors which should influence their proper design and performance, and assesses their favourable and unfavourable characteristics.
Guidelines for the determination of their feasibility in a particular situation are given.
Influence of Discharges from Storage Reservoirs on the Tastes and Odours Appearing in the Seine and Marne Rivers
Authors: Rizet M , Mouchet J 
Published: May 2018

This study was conducted in order to understand the taste and odour problems that occurred in the Seine and the Marne rivers during the severe drought of 1976.
Samples were taken every 15 days from several locations in the rivers themselves and from storage reservoirs upstream from Paris.
Algae and actinomycetes were identified and counted. Metabolite concentrations were measured. These data were correlated with threshold odor numbers and bacteriological water quality parameters.