bluuebunny/crossref_metadata_2025 huggingface dataset:
Linking integrated water resources management and integrated coastal zone management
Authors: Rasch P.S. , Ipsen N. , Malmgren-Hansen A. , Mogensen B.
Published: May 2018

Some of the world's most valuable aquatic ecosystems such as deltas, lagoons and estuaries are located in the coastal zone. However, the coastal zone and its aquatic ecosystems are in many places under environmental stress from human activities. About 50% of the human population lives within 200 km of the coastline, and the population density is increasing every day. In addition, the majority of urban centres are located in the coastal zone. It is commonly known that there are important linkages between the activities in the upstream river basins and the environment conditions in the downstream coastal zones. Changes in river flows, e.g. caused by irrigation, hydropower and water supply, have changed salinity in estuaries and lagoons. Land use changes, such as intensified agricultural activities and urban and industrial development, cause increasing loads of nutrients and a variety of chemicals resulting in considerable adverse impacts in the coastal zones. It is recognised that the solution to such problems calls for an integrated approach. Therefore, the terms Integrated Water Resources Management (IWRM) and Integrated Coastal Zone Management (ICZM) are increasingly in focus on the international agenda. Unfortunately, the concepts of IWRM and ICZM are mostly being developed independently from each other by separate management bodies using their own individual approaches and tools. The present paper describes how modelling tools can be used to link IWRM and ICZM. It draws a line from the traditional sectoral use of models for the Istanbul Master Planning and assessment of the water quality and ecological impact in the Bosphorus Strait and the Black Sea 10 years ago, to the most recent use of models in a Water Framework Directive (WFD) context for one of the selected Pilot River Basins in Denmark used for testing of the WFD Guidance Documents.
Escherichia coli removal in waste stabilization ponds: a comparison of modern and classical designs
Authors: Banda C.G. , Sleigh P.A. , Mara D.D.
Published: May 2018

Two PC-based waste stabilization pond design procedures, based on parameter uncertainty and 10,000-trial Monte Carlo simulations, were developed for a series of anaerobic, facultative and maturation ponds to produce ≤1000 E. coli per 100 ml for both 50% and 95% compliance. One procedure was based on the classical Marais equations and the other on the modern von Sperling equations. For the range of parameter variations selected the classical design procedure required less land area and had a shorter hydraulic retention time than the modern design procedure. For both procedures the design for 90% compliance required substantially more land and a longer retention time than the design for 50% compliance. Regulators and designers should seek a balance between system reliability (as set by the percentage compliance specified or adopted) and system costs, especially (but not only) in developing countries. It is recommended that new waste stabilization pond (WSP) systems be designed for compliance with a given E. coli effluent requirement by the classical procedure and that existing overloaded WSP systems be upgraded using the modern procedure.
Fuzzy control of nitrogen removal in predenitrification process using ORP
Authors: Peng Y. , Ma Y. , Wang S. , Wang X.
Published: May 2018

In order to meet increasingly stringent discharge standards, new applications and control strategies for the sustainable removal of nitrogen from wastewater have to be implemented. In the past years, numerous studies have been carried out dealing with the application of fuzzy logic to improve the control of the activated sludge process. In this paper, fuzzy control strategies of predenitrification systems are presented that could lead to better effluent quality and, in parallel, to a reduction of chemicals consumption. Extensive experimental investigations on lab scale plant studies have shown that there was excellent correlation between nitrate concentration and ORP value at the end of the anoxic zone. Results indicated that ORP could be used as an on-line fuzzy control parameter of nitrate recirculation and external carbon addition. The optimal value of ORP to control nitrate recirculation and external carbon addition was −86±2mV and −90±2mV, respectively. The results obtained with real wastewater also showed the good performance and stability of the fuzzy controllers independently from external disturbances. The integrated control structure of nitrate recirculation and external carbon addition in the predenitrification system is also presented.
Systems analysis of urban wastewater systems – two systematic approaches to analyse a complex system
Authors: Benedetti L. , Blumensaat F. , Bönisch G. , Dirckx G. , Jardin N. , Krebs P. , Vanrolleghem P.A.
Published: May 2018

This work was aimed at performing an analysis of the integrated urban wastewater system (catchment area, sewer, WWTP, receiving water). It focused on analysing the substance fluxes going through the system to identify critical pathways of pollution, as well as assessing the effectiveness of energy consumption and operational/capital costs. Two different approaches were adopted in the study to analyse urban wastewater systems of diverse characteristics. In the first approach a wide ranged analysis of a system at river basin scale is applied. The Nete river basin in Belgium, a tributary of the Schelde, was analysed through the 29 sewer catchments constituting the basin. In the second approach a more detailed methodology was developed to separately analyse two urban wastewater systems situated within the Ruhr basin (Germany) on a river stretch scale. The paper mainly focuses on the description of the method applied. Only the most important results are presented. The main outcomes of these studies are: the identification of stressors on the receiving water bodies, an extensive benchmarking of wastewater systems, and the evidence of the scale dependency of results in such studies.
Current state and development of the real-time control of the Berlin sewage system
Authors: Schroeder K. , Pawlowsky-Reusing E.
Published: May 2018

Since the 1970s, we have known about real-time control of urban drainage systems. However, global real-time control strategies still show a lack of implementation for large drainage systems of high complexity. In Berlin, Germany, a city of 3.5 million inhabitants covering an area of around 900km2, the demand for enhanced protection of the environment and growing economic pressure have led to an increasing application of control assets and concepts within the sewage system. In the framework of the project “Integrated Sewage Management”, the possibilities of a global and integrated control strategy for the Berlin system are examined. The paper is focused on the historical concept and design of the sewerage and the further improvement towards an environment-oriented system that builds the basis for today's considerations. The operational method and functionality of local regulators that have already been implemented are described. Further-more, the model-based methodology for the analysis of the system and the development of global control concepts, as well as the results of system analysis, are stated. On the basis of model simulations, it is shown that a global coordination of pump stations can lead to a reduction of sewer overflows, and consequently to an enhanced water protection.
Control of chironomid midge larvae in wastewater stabilisation ponds: comparison of five compounds
Authors: Craggs R. , Golding L. , Clearwater S. , Susarla L. , Donovan W.
Published: May 2018

Chironomid midge larvae are a valuable component of wastewater stabilisation pond (WSP) ecology. However, in high numbers, adult midge swarms can be a nuisance to near-by urban areas. Improving WSP treatment by incorporating aerobic or maturation ponds or by the addition of pre-treatment to reduce organic loading also increases the availability of aerobic sediment (midge larva habitat) in the pond system and the potential for midge nuisance problems. The efficacy of Maldison, an organophosphate traditionally used to control midge larvae in New Zealand WSPs, was compared to Bacillus thuringiensis var. israelensis (Bti), Methoprene, Pyriproxyfen and Diflubenzuron which are all more specific to insects and have fewer adverse environmental effects. Initial laboratory trials established the concentration of each compound required to achieve 95% control of the midge population. During 21-day small-scale trials within the WSP, Bti, Diflubenzuron and Maldison reduced live larvae numbers substantially (80–89%) compared to controls and adult midge emergence was markedly reduced by all compounds (72–96%). Large-scale trials with Bti (Vectobac® WG) powder (1000 μg/L) only caused a slight reduction in midge larvae numbers compared to controls and had little effect on adult emergence, however, Methoprene (Prolink XRG granules) (50 μgAI/L) reduced midge adult emergence by ∼80% over 25 days and has been used successfully to control several midge nuisance outbreaks.
Determination of the sedimentation constants for total suspended solids and the algal component in a full-scale primary facultative pond operating at high wind velocities under tropical conditions
Authors: Saraiva L.B. , Meneses C.G. Ribeiro , de Souza Melo H.N. , Araújo A.L. Calado , Pearson H.
Published: May 2018

This study evaluated the amount, distribution and sedimentation constant of solids in a full-scale primary facultative pond operating mostly under high wind conditions and the contribution made by the algal biomass. Solids deposition rates were measured using sedimentation traps placed in the inlet and outlet zones of the pond. Most sludge accumulation occurred, not surprisingly, in the inlet zone A1 with a sludge volume of 9072 m3 accumulating over an operating time of approximately 3 years. However, sludge deposition within this zone was uneven and affected by wind action. Mean proportionality constant (K) values for solids sedimentation were 3.02 and 5.70 for depths of 50 cm and 100 cm respectively for A1. In contrast in zone A3, (the outlet zone), reduced K values of 1.38 and 3.22 were obtained for depths of 50 cm and 100 cm respectively. The algal sedimentation constant varied from 0.8 d−1 in zone A1 to 0.02 d−1 in A3. These data suggest that in this large facultative pond the wind, blowing predominantly from the direction of the outlets towards the pond inlets, had a greater influence on solids deposition than the bulk hydraulic flow and also kept the pond completely mixed for most of the time.
Dissolved organic matter from agricultural fields in the irrigation period
Authors: Shim S. , Kim B. , Hosoi Y. , Masuda T.
Published: May 2018

The aim of this study was to quantify and characterize the dissolved organic carbon (DOC) of paddy fields and crop fields in Tottori, Japan. Dissolved organic carbon (DOC) and ultraviolet (UV) absorbance was measured for the filtrated water of each samples. DOC concentration and SUVA (specific UV absorbance) of biodegradation analysis samples were determined around 50 days after the incubation. In the Fukui paddy fields, DOC concentration varied seasonally from 1.1 to 10.1mg.Cl−1, showing higher concentration in heavy runoff of non-agriculture period in April. However, DOC concentration variation did not always correspond to rainfall. The Obadake paddy fields also showed a similar pattern with Fukui paddy fields. The daily DOC discharge per area in Fukui (up), Fukui (down), Obadake (south), Obadake (north) paddy fields influent from paddy fields were 0.02, 0.0161, 0.0135 and 0.0027kg.a−1.day−1, respectively. These differences resulted from differences in agricultural types and customs of farmers according to paddy fields and fields. Also, SUVA (an indirect means to evaluate humic substances (hydrophobic fraction)) of the studied influent waters from paddy fields were generally lower than the influent waters from crop fields. The non-biodegradable DOC accounted for 50.2–98%, 46.8–85.5% of the total DOC in the paddy fields and crop fields.
Development of a geographical information system for pesticide assessment on an Ecuadorian watershed
Authors: Matamoros D.E. , Griensven A. van , Biesen L. van , Vanrolleghem P.A.
Published: May 2018

Banana production is very important for the Ecuadorian national income, but it is also a potential source of river pollution in the country. Current research is focusing on the use of GIS to perform pesticide assessment of a river basin that includes banana as its main agricultural activity. The Agricultural Non Point Source Model (AGNPS) is being used to perform pesticide assessment in the basin. The model structure and type of needed data was identified. By applying GIS methodology, a complete set of cartographical information was obtained to supply input data to the pesticide model. In addition, ready-to-print maps were useful by-products for farmers.
Microphyte and macrophyte-based lagooning in tropical regions
Authors: Noumsi I.M. K. , Nya J. , Akoa A. , Eteme R.A. , Ndikefor A. , Fonkou T. , Brissaud F.
Published: May 2018

A 720 m2 plant made of 8 ponds in series, set in Yaounde (Cameroon), was successively operated as a macrophyte-based system (type M) from November 1997 to October 98, a microphyte-based system (type m) from October 1999 to September 2000 and a combination of macrophyte and microphyte ponds (type M+m) from May to July 2001. Average applied loads varied over the years; from 420 kg. BOD5 ha−1 d−1 on the year 1997/98, the loads reached 510 kg BOD5 ha−1 d−1 in 1999/2000 and 500 in 2001. Though the system became more and more overloaded and sludge accumulated rapidly in the first ponds, it provided average removals of SS, BOD5 and COD that were always higher than 90% whatever the type of lagooning. Performances in the removal of SS, organic matter and the abatement of N-NH4+ and PO43− did not significantly differ according to the type of lagooning and the applied load. Macrophyte lagooning did not show any definitive superiority as to nutrient removal when compared to microphyte lagooning. Microphyte lagooning was the most effective process in faecal indicators removal.
Flood impact on water quality of small urban streams
Authors: Nábělková J. , Šťastná G. , Komínková D.
Published: May 2018

Flood situation (August 2002) in small urban streams radically changed status of water ecosystem, which had been created naturally and anthropogenically for a long time. The aim of the after-flood research has been to record development of a creek recovery in positive as well as negative sense: recovery of benthic colonisation and reloading of contaminants (heavy metals) in bottom sediment. The Botic creek (its one section) was chosen as an experimental stream. This section of the creak is influenced by combine sewer system (two overflows – CSOs) as well as storm sewer system (one outlet – SSO). Heavy metals concentrations in water, sediment and body tissue of benthic organisms of the Botic creek and quality of benthic communities were monitored long term before flood. Comparison of results before and after flood can better assess impact of extreme water stage on a small stream.
Sewage outfall plume dispersion observations with an Autonomous Underwater Vehicle
Authors: Ramos P. , Cunha S.R. , Neves M.V. , Pereira F.L. , Quintaneiro I.
Published: May 2018

This work represents one of the first successful applications of Autonomous Underwater Vehicles (AUVs) for interdisciplinary coastal research. A monitoring mission to study the shape and estimate the initial dilution of the S. Jacinto sewage outfall plume using an AUV was performed on July 2002. An efficient sampling strategy enabling greater improvements in spatial and temporal range of detection demonstrated that the sewage effluent plume can be clearly traced using naturally occurring tracers in the wastewater. The outfall plume was found at the surface highly influenced by the weak stratification and low currents. Dilution varying with distance downstream was estimated from the plume rise over the outfall diffuser until a nearly constant value of 130:1, 60m from the diffuser, indicating the near field end. Our results demonstrate that AUVs can provide high-quality measurements of physical properties of effluent plumes in a very effective manner and valuable considerations about the initial mixing processes under real oceanic conditions can be further investigated.
Anaerobic digestion: impact of future greenhouse gases mitigation policies on methane generation and usage
Authors: Greenfield P.F. , Batstone D.J.
Published: May 2018

The debate as to whether carbon dioxide, methane, nitrous oxide and other greenhouse gas emissions will become subject to increasing regulation, increased restrictions, and probably to some form of carbon tax, has moved from a simple “yes” or “no” to “when”. Wastewater treatment plants will be significantly impacted by increased energy costs and by specific regulations and/or penalties associated with emissions of methane and nitrous oxide. In this paper, the greenhouse gases emissions of different wastewater process options are estimated. The paper outlines the increasing need for wastewater treatment plants to factor greenhouse gas mitigation issues into their medium- as and long-term strategies, and identifies anaerobic enhouse as processes as being at the core of such strategies. Further, the paper identifies a number of key research challenges to be addressed if such strategies are to play a larger role in attenuating the likely impacts of GHG mitigation requirements on wastewater treatment plant design and operation.
Effect of pretreatment on acid fermentation of organic solid waste
Authors: Kim H.J. , Choi Y.G. , Kim D.Y. , Kim D.H. , Chung T.H.
Published: May 2018

The effect of various pretreatment methods on acidogenesis of food waste from a cafeteria was investigated. Thermal, enzymatic, and combined thermal-enzymatic batch pretreatment were conducted. Solubilization of food waste in thermal or enzymatic pretreatment increased with either increasing thermal duration or enzyme dosage, respectively. An optimal condition in thermal or enzymatic pretreatment was 60 min of thermal processing or 0.1% (v/v) of enzyme dosage level, respectively, based on volatile suspended solids (VSS) reduction. In the combined pretreatment, increased thermal duration also increased VSS reduction and the solubilization efficiency was higher than that in only enzymatic or thermal pretreatment. The maximum volatile fatty acids (VFAs) production and the highest VFAs fraction in soluble COD in the acid fermentation were achieved with the food waste after 60 min of thermal processing followed by 0.1% (v/v) enzymatic treatment. Increase in VFAs production of the fermenter was over 380% compared to the control fermenter without any pretreatment.
Effect of co-substrate, biomass and sulfate concentration on the performance of a control strategy used to determine the anaerobic stage length of an anaerobic/aerobic SBR degrading p-nitrophenol
Authors: Buitrón G. , Moreno G. , García M.E. , Moreno J.
Published: May 2018

The effect of the p-nitrophenol to propionic acid ratio, the biomass concentration, and the presence of sulfates on the performance of a control strategy of an anaerobic/aerobic SBR degrading p-nitrophenol was studied. The duration of the anaerobic stage was controlled by an algorithm based on the on-line measurement of the oxidation-reduction potential, which indicates the end of the reduction of p-nitrophenol to p-aminophenol. It was observed that no significant influence on the performance of the algorithm was found when the co-substrate, the biomass concentration and the presence of sulfates were varied, indicating the robustness of the control strategy. Only for the case when a low concentration of co-substrate was used, was there no transformation of p-nitrophenol.
An integrated system to remote monitor and control anaerobic wastewater treatment plants through the internet
Authors: Bernard O. , Chachuat B. , Hélias A. , Le Dantec B. , Sialve B. , Steyer J.-P. , Lardon L. , Neveu P. , Lambert S. , Gallop J. , Dixon M. , Ratini P. , Quintabà A. , Frattesi S. , Lema J.M. , Roca E. , Ruiz G. , Rodriguez J. , Franco A. , Vanrolleghem P. , Zaher U. , De Pauw D.J.W. , De Neve K. , Lievens K. , Dochain D. , Schoefs O. , Fibrianto H. , Farina R. , Alcaraz Gonzalez V. , Gonzalez Alvarez V. , Lemaire P. , Martinez J.A. , Esandi F. , Duclaud O. , Lavigne J.F.
Published: May 2018

The TELEMAC project brings new methodologies from the Information and Science Technologies field to the world of water treatment. TELEMAC offers an advanced remote management system which adapts to most of the anaerobic wastewater treatment plants that do not benefit from a local expert in wastewater treatment. The TELEMAC system takes advantage of new sensors to better monitor the process dynamics and to run automatic controllers that stabilise the treatment plant, meet the depollution requirements and provide a biogas quality suitable for cogeneration. If the automatic system detects a failure which cannot be solved automatically or locally by a technician, then an expert from the TELEMAC Control Centre is contacted via the internet and manages the problem.
Application of the IWA Anaerobic Digestion Model (ADM1) for simulating full-scale anaerobic sewage sludge digestion
Authors: Shang Y. , Johnson B.R. , Sieger R.
Published: May 2018

A steady-state implementation of the IWA Anaerobic Digestion Model No. 1 (ADM1) has been applied to the anaerobic digesters in two wastewater treatment plants. The two plants have a wastewater treatment capacity of 76,000 and 820,000 m3/day, respectively, with approximately 12 and 205 dry metric tons sludge fed to digesters per day. The main purpose of this study is to compare the ADM1 model results with full-scale anaerobic digestion performance. For both plants, the prediction of the steady-state ADM1 implementation using the suggested physico-chemical and biochemical parameter values was able to reflect the results from the actual digester operations to a reasonable degree of accuracy on all parameters. The predicted total solids (TS) and volatile solids (VS) concentration in the digested biosolids, as well as the digester volatile solids destruction (VSD), biogas production and biogas yield are within 10% of the actual digester data. This study demonstrated that the ADM1 is a powerful tool for predicting the steady-state behaviour of anaerobic digesters treating sewage sludges. In addition, it showed that the use of a whole wastewater treatment plant simulator for fractionating the digester influent into the ADM1 input parameters was successful.
Cold-climate vegetative buffer zones as pesticide-filters for surface runoff
Authors: Syversen N.
Published: May 2018

Vegetative buffer zones adjacent to watercourses can be effective filters for diffuse pollution from agriculture. Several investigations, even during snowmelt season, have shown that retention of sediments and sediment-bound nutrients in runoff water has been high through buffer zones (BZ). It is likely that BZ also can be effective filters for sediment-bound pesticides. The retention of glyphosate, propiconazole, fenpropimorph and soil particles was studied in surface runoff experiments with 5 m wide buffer zones. Volume proportional samples were collected after each runoff episode (1999–2002). The distribution coefficient (Kd) shows moderate to high adsorption of the pesticides to the experimental soil. Results show average retention efficiency of about 51%, 48%, 85% and 34% for particles, glyphosate, propiconazole and fenpropimorph, respectively. The amount of AMPA (which is a degradation product of glyphosate), entering the BZ was high; approximately the same amount as for glyphosate. The retention efficiency through the BZ for AMPA was about 67%. There were no significant differences in removal efficiency (in %) between winter with snowmelt and summer. This is possibly due to detachment of coarser aggregates during winter, which trap more easily in the BZ. The conclusion based on this study suggests BZ to be contributors to reduced pesticide input to surface waters.
Developing an independent, generic, phosphorus modelling component for use with grid-oriented, physically based distributed catchment models
Authors: Nasr A. , Taskinen A. , Bruen M.
Published: May 2018

Grid-oriented, physically based catchment models calculate fields of various hydrological variables relevant to phosphorus detachment and transport. These include (i) for surface transport: overland flow depth and flow in the coordinate directions, sediment load, and sediment concentration and (ii) for subsurface transport: soil moisture and hydraulic head at various depths in the soil. These variables can be considered as decoupled from any chemical phosphorus model since phosphorus concentrations, either as dissolved or particulate, do not influence the model calculations of the hydrological fields. Thus the phosphorus concentration calculations can be carried out independently from and after the hydrological calculations. This makes it possible to produce a separate phosphorus modelling component which takes as input the hydrological fields produced by the catchment model and which calculates, at each simulation time step, the phosphorus concentrations in the flows. This paper summarises the equations and structure of such a Grid Oriented Phosphorus Component (GOPC) developed by the authors for simulating phosphorus concentrations and loads using the outputs of a fully distributed physical based hydrological model. The GOPC performance is illustrated by an example of a simplified hypothetical catchment subjected to some ideal conditions.
Urban diffuse sources of faecal indicators
Authors: O'Keefe B. , D'Arcy B.J. , Davidson J. , Barbarito B. , Clelland B.
Published: May 2018

Increasing concern about bathing water quality in Scotland has led to renewed interest in diffuse sources, as well as the already closely monitored municipal sewage effluents and combined sewer overflows (CSOs) that have been the subject of multi-million pound capital expenditure schemes for several years. Early investigations of diffuse sources focused on rural land uses. This paper is an initial effort to consider the possible significance of urban diffuse sources. A review of the potential for diffuse urban sources includes consideration of sewage pollution in surface water sewers, as well as non-human sources such as pigeon and other bird roosts, and faecal material from pets such as dogs and cats. Portobello beach in Edinburgh is the case study selected, because of earlier work done by Scottish Water and SEPA. The Figgate Burn crosses Edinburgh to discharge onto the beach at Portabello, and pollution sources in its catchment are described. Additional information is reported from Dunfermline, where the sewer network has provided examples of three ways in which sewage pollution can occur in urban streams, and also Scottish examples of measures to control some non-human sources (e.g. SUDS).
Persistent pollutants urban rivers sediment survey: implications for pollution control
Authors: Wilson C. , Clarke R. , D'Arcy B.J. , Heal K.V. , Wright P.W.
Published: May 2018

The impacts of diffuse urban sources of pollution on watercourses are quantified. A survey of nine urban streams in Scotland for persistent pollutants in stream sediments is described, together with sediments from SUDS ponds. Determinands reported are: PAHs, total hydrocarbons, and toxic metals (As, Zn, Ni, Pb, Cu, Cr, Cd). Results highlight hydrocarbons as a major urban pollutant, and show significant sediment contamination by toxic metals. The metals that occurred in the highest concentrations varied across the nine streams, but Pb, Cr, Ni, Zn and Cu most frequently present exceeded sediment quality standards. The pattern of contamination by PAHs suggested that pyrolytic sources were more ubiquitous and present in greater quantities than oil spill sources in these urban catchments. Exceptions were the sites below industrial estates. The findings indicate that four levels of activity will be needed to control urban diffuse sources of pollution: reductions in quantities of toxic pollutants used by manufacturers in the motor and construction industries; housekeeping measures to minimise storage and handling risks for oil and chemicals; public engagement to minimise polluting activities such as dumping oil and chemicals, and private car use; use of SUDS technology, including retro-fits in the worst affected urban areas.
An assessment of the impact of the proposed EU bathing water directive on Irish coastal bathing area compliance
Authors: Chawla R. , Real K. , Masterson B.
Published: May 2018

An assessment of the impact of the new microbial water quality standards of the proposed EU Bathing Water Directive on the classification of designated Irish coastal bathing areas is presented. The new standards are applied retrospectively to the microbial water quality results for the bathing seasons of 1999, 2000 and 2001, and the outcome is compared with that recorded under the present Bathing Water Directive. A Microsoft EXCEL application was developed to generate the retrospective bathing area classifications according to the proposed Directive (Excellent, Good, Poor). It was found that the number of Irish coastal bathing areas not attaining ‘Excellent’ classification (as would be required at present for the Blue Flag award) was trebled; the number attaining ‘Good’ classification was increased by about 50%, and the number attracting ‘Poor’ classification (equivalent to ‘Fail’ under the present Directive) was increased nine-fold. Some of the shortcomings of the proposed Directive and suggestions for its revision are discussed.
Diffuse inputs of nutrients to Dublin Bay
Authors: Wilson James G.
Published: May 2018

The River Liffey is the main source of diffuse nutrients to Dublin Bay and accounts for some 85% of all riverine inputs. The total load from the various rivers has been calculated at some 6601 kg N d1 and 748 kg P d1, of which around 82% and 52% are in the form of DIN and phosphate respectively. Sewage discharge adds almost the same again to the load, with minor contributions from the sediments (which may simply be remineralising the particulates) and from nitrogen fixation. However, these inputs are very much less than those exchanged twice-daily by tidal action. These contributions are due to change very shortly with the advent of the new STW in Dublin, but the major change may be more in the speciation of the nutrients, and in particular the dissolved/particulate balance.
Nutrient emissions from diffuse and point sources into the River Danube and its main tributaries for the period of 1998–2000 – results and problems
Authors: Schreiber H. , Behrendt H. , Constantinescu L.T. , Cvitanic I. , Drumea D. , Jabucar D. , Juran S. , Pataki B. , Snishko S. , Zessner M.
Published: May 2018

Nutrient emissions by point and diffuse sources were estimated for 388 sub-catchments of the Danube river basin for the period 1998–2000 by means of the Model MONERIS. For nitrogen total emissions of 684 kt/a N were estimated for the Danube basin. 80% of these emissions were caused by diffuse sources (mainly groundwater, urban areas and tile drainage). For phosphorus the emission was 57 kt/a P, with a contribution of diffuse sources to this sum of 58%. The comparison of calculated and observed loads shows that the mean deviation for the investigated sub-catchments of the Danube river basin is 20% for dissolved inorganic nitrogen and 34% for phosphorus. The spatial resolution of the emission calculations allows the identification of regional hot spots and the derivation of specific regional measures to reduce the emissions into the Danube and consequently into the Western Black Sea.
Effect of uncertainties in agricultural working schedules and Monte-Carlo evaluation of the model input in basin-scale runoff model analysis of herbicides
Authors: Matsui Y. , Inoue T. , Matsushita T. , Yamada T. , Yamamoto M. , Sumigama Y.
Published: May 2018

In the prediction of time-series concentrations of herbicides in river water with diffuse-pollution hydrological models, farming schedules (the dates of herbicide application and drainage of irrigation water from rice paddies) greatly affect the runoff behavior of the herbicides. For large catchments, obtaining precise data on farming schedules is impractical, and so the model input inevitably includes substantial uncertainty. This paper evaluates the effectiveness of using the Monte-Carlo method to generate sets of estimated farming schedules to use as input to a GIS-based basin-scale runoff model to predict the concentrations of paddy-farming herbicides in river water. The effects of using the Monte-Carlo method to compensate for uncertainty in the evaluated parameters for herbicide decomposition and sorption were also evaluated.
GIS-based quantification of future nutrient loads into Lake Peipsi/Chudskoe using qualitative regional development scenarios
Authors: Mourad D.S.J. , Van der Perk M. , Gooch G.D. , Loigu E. , Piirimäe K. , Stålnacke P.
Published: May 2018

This study aims at the quantification of possible future nutrient loads into Lake Peipsi/Chudskoe under different economic development scenarios. This drainage basin is on the borders of Russia, Estonia and Latvia. The sudden disintegration of the Soviet Union in 1991 caused a collapse of agricultural economy, and consequently, a substantial decrease of diffuse and point-source nutrient emissions. For the future, uncertainties about economic development and the priorities that will be set for this region make it difficult to assess the consequences for river water quality and nutrient loads into the lake. We applied five integrated scenarios of future development of this transboundary region for the next twelve to fifteen years. Each scenario consists of a qualitative story line, which was translated into quantitative changes in the input variables for a geographical information system based nutrient transport model. This model calculates nutrient emissions, as well as transport and retention and the resulting nutrient loads into the lake. The model results show that the effects of the different development scenarios on nutrient loads are relatively limited over a time span of about 15 years. In general, a further reduction of nutrient loads is expected, except for a fast economic development scenario.
Effects of water protection measures on the profitability of farms
Authors: Schultheiβ U. , Jäger P. , Döhler H. , Eurich-Menden B.
Published: May 2018

The effect of different management measures on the nutrient losses from crop and animal husbandry systems, in particular nitrogen, and on the total income of model farming enterprises was investigated. Such measures are considered as powerful options for meeting the requirements of “cross compliance” within the Agenda 2000 midterm review of the CAP. Optimisation of the storage and handling of animal manure was shown to be the most important and cost effective measure to reduce nutrient losses on farms. Other measures such as protein and phosphorus adapted feeding, maintaining a year-round cover crop on arable land and conservation tillage were also effective and it is recommended that these are adopted into farming practices. In general, measures that have both a high potential to reduce nutrient losses and are cheap to apply, and therefore have little effect on the overall profitability of farms, should be given priority in water protection policies.
Continuous biological ferrous iron oxidation in a submerged membrane bioreactor
Authors: Park D. , Lee D.S. , Park J.M.
Published: May 2018

Microbial oxidation of ferrous iron may be available alternative method of producing ferric iron, which is a reagent used for removal of H2S from biogas. In this study, a submerged membrane bioreactor (MBR) system was employed to oxidize ferrous iron to ferric iron. In the submerged MBR system, we could keep high concentration of iron-oxidizing bacteria and high oxidation rate of ferrous iron. There was membrane fouling caused by chemical precipitates such as K-jarosite and ferric phosphate. However, a strong acidity (pH 1.75) of solution and low ferrous iron concentration (below 3000 mg/l) significantly reduced the fouling of membrane module during the bioreactor operation. A fouled membrane module could be easily regenerated with a 1 M of sulfuric acid solution. In conclusion, the submerged MBR could be used for high-density culture of iron-oxidizing bacteria and for continuous ferrous iron oxidation. As far as our knowledge concerns, this is the first study on the application of a submerged MBR to high acidic conditions (below pH 2).
Efficiency of membrane processes for taste and odor removal
Authors: Bruchet A. , Laîné J.M.
Published: May 2018

The occurrence of tastes and odors (T&O) in drinking water is considered as one of the main problems by the drinking water companies. Thus, several treatment processes were developed over the years to control T&O including air stripping, activated carbon and oxidation using ozone. However, little information is available in the literature on the use of membranes for T&O removal. Therefore, the objectives of this paper are to present potential of membrane processes for removal of taste and odor causing compounds. Several membranes were tested including ultrafiltration (UF), UF combined with powdered activated carbon (PAC), nanofiltration (NF) and low pressure reverse osmosis (LP RO) membranes. The results of this study indicate that the combination of UF with PAC is effective for T&O control whereas the benefit of NF and LP RO remains unclear for T&O control.
Feasibility study on the removal of nitrous compounds with a hollow-fiber membrane biofilm reactor
Authors: Shin J.-H. , Sang B.-I. , Chung Y.-C. , Choung Y.-K.
Published: May 2018

The objective of this study was to develop an integrated nitrogen treatment system using autotrophic organisms. A treatment system consists of an aerobic hollow-fiber membrane biofilm reactor (HfMBR) and anaerobic HfMBR. In the aerobic HfMBR, a mixture gas of air and O2 was supplied through the fibers for nitrification. Denitrification occurred in the anaerobic HfMBR using H2 as the electron donor. The treatment system was continuously operated for 190 days. NH4-N removal efficiencies ranging from 95% to 97% were achieved at NH4-N concentrations of influent ranging from 50 to 100 mg N/L. When glucose was added to the influent, the simultaneous nitrification and denitrification occurred in the aerobic HfMBR, and nitrogen removal rates were changed according to the COD/NH4-N ratio of influent. In the anaerobic HfMBR, autotrophic denitrification using H2 occurred and the removal rates achieved in this study were 23–58 mg N/m2 d. In this study, the achieved removal efficiency was lower than other study findings; however, the result suggested that this hybrid HfMBR system can be used effectively for nitrogen removal in oligotrophic water.
Application of membrane bioreactor system with full scale plant on livestock wastewater
Authors: Kim H. , Kim H.-S. , Yeom I.-T. , Chae Y.-B.
Published: May 2018

A full-scale plant of an MBR system treating livestock wastewater has shown impressive results. The Cheorwon County Environmental Authorities adopted the MBR process with UF membrane for retrofitting the old plant, which removes organic matter, nitrogen and phosphorus at a high level. According to 6 months operation data, BOD and SS removal were about 99.9% and CODMn, TN and TP removal were 92.0%, 98.3% and 82.7%, respectively. It is considered that the temperature at the bioreactor has to be controlled to be below 40 °C so as to ensure sufficient nitrification. It appeared that the MBR system is competitive with other conventional technologies for treatment of livestock wastewater such as piggery waste.
Prediction of sulfide formation in sewer pressure mains based on the IWA Anaerobic Digestion Model No. 1 (ADM1)
Authors: Freudenthal K. , Koglatis J. , Otterpohl R. , Behrendt J.
Published: May 2018

In this paper a new approach is presented to predict sulfide formation in sewers based on the IWA Anaerobic Digestion Model No. 1 (ADM1). Compared with existing models the ADM1 has two crucial advantages. Firstly, it simulates anaerobic digestion processes, of which sulfide formation is the final step. Secondly, it uses a more detailed description of the waste water composition. In order to obtain reliable data for calculation an experimental set-up for measuring the Oxygen Uptake Rate (OUR) is used. An implementation of sulfide formation processes into the model matrix is proposed.
Effect of enzymatic pretreatment on solubilization and volatile fatty acid production in fermentation of food waste
Authors: Kim H.J. , Choi Y.G. , Kim G.D. , Kim S.H. , Chung T.H.
Published: May 2018

Food waste can be a valuable carbon source in biological nutrient removal (BNR) systems because of the high C/N and C/P ratio. However, pretreatment is necessary to promote hydrolysis of food waste because of the high concentration of volatile solids associated with organic matter. The influence of the enzymatic pretreatment on acid fermentation of food waste was investigated in this study. Solubilization of particulate matter in food waste was carried out using commercial enzymes. The acidification efficiency and the volatile fatty acid (VFA) production potential of enzymatically pretreated food waste were examined. The highest volatile suspended solid (VSS) reduction was obtained with an enzyme mixture ratio of 1: 2: 1 for carbohydrase: protease: lipase. An optimum enzyme dosage for solubilization of food waste was 0.1% (V/V) with the enzyme mixture ratio of 1: 2: 1. In the acid fermen- tation of enzymatically pretreated food waste, the maximum VFA production and the highest VFA fraction in soluble COD (SCOD) were also achieved at 0.1% (V/V) of total enzyme dosage. Increase in VFA production at this level of enzyme dosage was over 300% compared with the control fermenter. The major form of VFA produced by fermentation was n-butyrate followed by acetate.
A new approach to improve sludge dewatering using a semi-continuous hydraulic press system
Authors: Kolisch G. , Boehler M. , Arancibia F.C. , Pinnow D. , Krauss W.
Published: May 2018

In future, it will be necessary to incinerate an increasing proportion of the sludge produced by public wastewater treatment. In this context, equipment for more effective dewatering of sewage sludge is required. A hydraulic press system (Bucher HP) which has been used to date in the food industry could represent an alternative to the sludge dewatering systems currently used. The basic suitability of this press system was demonstrated in comprehensive industrial-scale trials at the Glarnerland STP (Switzerland). Dry solids contents of up to 43% were measured in the pressed sludge. Currently, the optimization of individual process parameters is being investigated in a pilot plant at the Schwelm STP operated by Wupperverband (Germany).
The Ruhrverband sewage sludge disposal concept in the conflict between European and German standards and regulations
Authors: Evers P. , Schmitt F. , Albrecht D.R. , Jardin N.
Published: May 2018

The Ruhrverband, acting as a water association responsible for integrated water resources management within the entire natural river basin of the Ruhr, operates a network of 83 wastewater treatment plants (WWTPs) and connected sludge disposal facilities.

According to German regulations, the disposal of sewage sludge containing more than 5% of organic dry solids will be prohibited as of 1 June 2005. In Germany, the only future alternative to incineration will be the agricultural utilization of sludge. However, this way of sludge disposal is presently the subject of critical discussions in Germany because of the organic and inorganic toxic substances, which may be contained in sewage sludge, despite the fact that very stringent standards are to be met by agricultural uses. On the other hand, application of sewage sludge to agricultural land is explicitly supported by the European Sewage Sludge Directive 86/278/EEC.

In the face of this controversial situation the Ruhrverband has initiated, in 2000, the development of a comprehensive and sustainable sludge and waste disposal concept for all wastewater facilities it operates in the entire Ruhr River Basin. The concept includes de-central sludge digestion and dewatering and subsequent transport to two central sludge incineration plants. It is expected that in future not more than 5% of all sludges produced in Ruhrverband's WWTPs will be used in agriculture. That means, the major part of 95% will have to be incinerated.
Production integrated treatment of textile wastewater by closing raw material cycles
Authors: Krull R.
Published: May 2018

A method for the in-house treatment of partial wastewater flows and the recycling of treated process water into the textile finishing process was developed in order to recycle effluents from textile finishing industry and feed them back into the production process. The method is based on a two-stage biological anaerobic–aerobic process to split colouring wastewater agents and to degrade organic sub-stances contained in the water as well as a chemical stage to remove the remaining color of the water with the help of ozone. In the framework of a research and development project a demonstration plant for a treatment capacity of 1440m3 per working day was installed and started in a textile finishing company. At the plant, a wastewater flow and a recycling flow are treated separately in two different treatment lanes. Approximately 40% of the total wastewater flows, i.e. 576m3/d are treated in the wastewater lane, and a maximum of 60% of total wastewater, i.e. 864m3/d are treated in the recycling lane. Thanks to the preliminary treatment of wastewater flows, which are discharged into the municipal sewage works, a reduction of average COD levels in the sewage works effluents could be achieved.
Electron beam treatment of textile dyeing wastewater: operation of pilot plant and industrial plant construction
Authors: Han B. , Kim J. , Kim Y. , Choi J.S. , Makarov I.E. , Ponomarev A.V.
Published: May 2018

A pilot plant for treating 1000m3/day of dyeing wastewater with e-beam has been constructed and operated since 1998 in Daegu, Korea together with the biological treatment facility. The wastewater from various stages of the existing purification process has been treated with an electron beam in this plant, and it gave rise to elaborating the optimal technology of the electron beam treatment of wastewater with increased reliability for instant changes in the composition of wastewater. Installation of the e-beam pilot plant resulted in decolorizing and destructive oxidation of organic impurities in wastewater, appreciable reduction of chemical reagent consumption, in reduction of the treatment time, and in increase in the flow rate limit of existing facilities by 30–40%. Industrial plant for treating 10,000m3/day each, based upon the pilot experimental result, is under construction and will be finished by 2005. This project is supported by the International Atomic Energy Agency (IAEA) and Korean Government.