References of "Water Science & Technology"
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See detailEstimating the costs of collective treatment of wastewater: the case of Walloon Region (Belgium)
Dogot, Thomas ULg; Xanthoulis, Yanni; Fonder, Nathalie et al

in Water Science & Technology (2010), 62(3), 640-648

This paper contributes to a better understanding of costs for collective wastewater treatment in the Walloon Region (Belgium). Based on a large set of data, unit costs to population equivalents are ... [more ▼]

This paper contributes to a better understanding of costs for collective wastewater treatment in the Walloon Region (Belgium). Based on a large set of data, unit costs to population equivalents are modelled. Considering investment as well as exploitation costs, the model includes not only wastewater treatment plants but also collector and sewage networks in an integrated approach at the technical basin level. Beyond this modelling, each type of process is analyzed independently in order to explore the structure of investment costs and their variation factors. Then, the model was used to forecast the upcoming expenses for 36 areas which are not yet equipped with collective wastewater treatment facilities. In light of these results, strategic choices for decision makers are discussed. [less ▲]

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See detailActivated sludge behaviour in a batch reactor in the presence of antibiotics: study of extracellular polymeric substances
Avella, Catalina; Essendoubi, M; Louvet, Jean-Noël ULg et al

in Water Science & Technology (2010)

The influence of Erythromycin, Roxithromycin, Amoxicillin, Tetracycline and Sulfamethoxazole on municipal sludge in batch reactors was investigated. The study was focused on extracellular polymeric ... [more ▼]

The influence of Erythromycin, Roxithromycin, Amoxicillin, Tetracycline and Sulfamethoxazole on municipal sludge in batch reactors was investigated. The study was focused on extracellular polymeric substances (EPS) as indicator of bacteria sensitivity to toxic agents. The EPS were analysed by UV-Vis and FT-IR spectroscopies and by size exclusion chromatography. It was found that Erythromycin and Roxithromycin induced a significant increase of bound EPS in flocs. This was attributed to a protection mechanism of the bacteria. Erythromycin was the only antibiotic which inhibited COD and nitrogen removal. [less ▲]

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See detailGrassed Buffer Strips as Nitrate Diffuse Pollution Remediation Tools: Management Impact on the Denitrification Enzyme Activity
Cors, Marie; Tychon, Bernard ULg

in Water Science & Technology (2007), 55(3), 25-30

The management of grassed buffer strips proved to be an efficient remediation technique in controlling nitrogen losses to surface water. In south Belgium, agri-environmental policies have encouraged ... [more ▼]

The management of grassed buffer strips proved to be an efficient remediation technique in controlling nitrogen losses to surface water. In south Belgium, agri-environmental policies have encouraged farmers to seed buffer strips along rivers, in zones where the soil was previously devoted to agricultural production. We wanted to assess how important denitrification is in a buffer strip in comparison with a cropped field. The study investigated the denitrifiying enzyme activity (DEA) of two contiguous buffer strips with different management stories. The eastern part of the buffer strip was seeded in 1999. The western part of the buffer strip is a piece of crop field abandoned by the farmer 20 years ago and not managed for the last 10 years. This experimental study demonstrates that the denitrification enzyme activity in a riparian buffer strip is significantly higher than in the adjacent cropped field (3.67 and 2.12 mgNkg(-1)d(-1) respectively). The DEA was significantly different between the two buffer strips under comparison, assessing that the management of the buffer strips has a dominant effect on DEA. The old unmown buffer strip is potentially more efficient in the nitrate removal process than the 6-year-old seeded buffer strip. [less ▲]

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See detailRiver contract in Wallonia (Belgium) and its application for water management in the Sourou valley (Burkina Faso)
Rosillon, Françis ULg; Vander Borght, Paul ULg; Bado Sama, H.

in Water Science & Technology (2005), 52(9), 85-93

Inspired by the experience of a river contract in Wallonia (Belgium) since 1990, the implementation of a first river contract has been initiated in a West African country, Burkina Faso. This application ... [more ▼]

Inspired by the experience of a river contract in Wallonia (Belgium) since 1990, the implementation of a first river contract has been initiated in a West African country, Burkina Faso. This application is not limited to a simple transposition of the Walloon model. The Burkina context calls for adaptation to the local environmental and socio-economical realities with an adequate partnership management. The importance of the mobilization around this project of institutional partners, as well as local collectivities, agricultural producers and water users in general reveals the great expectations of the actors concerning this new tool of water participative management. But will the latter be equal to the task? A first assessment has been drawn up one year after the launch. During the first year of the project, a participative diagnostic was implemented but the understanding of basic notions of water management such as 'river' (not translatable in the local language), 'watershed', 'contract' were not obvious. After the identification of functions and uses of water in the basin, an environmental survey was started. This approach allows study with the river committees of the priority actions to be developed as a first project of restoration of the gallery forest alongside the stream to fight against desertification. This project of integrated and participative management of water at sub-basin level is a concrete example of solidarity and exchange know-how between North and South in the context of a sustainable development. [less ▲]

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See detailSensor arrays : an inspired idea or an objective measurement of environmental odours ?
Stuetz, R. M.; Nicolas, Jacques ULg

in Water Science & Technology (2001), 44(9), 53-58

The measure of annoyance odours from sewage treatment, landfill and agricultural practise has become highly significant in the control and prevention of odorous emissions from existing facilities and is ... [more ▼]

The measure of annoyance odours from sewage treatment, landfill and agricultural practise has become highly significant in the control and prevention of odorous emissions from existing facilities and is crucial for new planning applications. Current methods (such as GC-MS analysis, H2S and NH3 measurements) provide an accurate description of chemical compositions or act as surrogates for odour strength, but tell us very little about the perceived effect, whereas olfactometry gives the right human response but is very subjectivity and expensive. The use of non-specific sensor arrays may offer an objective and on-line instrument for assessing olfactive annoyance. Results have shown that sensor array systems can discriminate between different odour sources (wastewater, livestock and landfill). The response patterns from these sources can be significantly different and that the intensity of sensor responses is proportional to the concentration of the volatiles. The correlation of the sensors responses against odour strengths have also shown that reasonable fits can be obtained for a range of odour concentrations (100 - 800,000 ou/m3). However, the influence of environmental fluctuations (humidity and temperature) on sensor baselines still remains an obstacle, as well as the need for periodic calibration of the sensory system and the choice of a suitable gas for different environmental odours. [less ▲]

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See detailSome influences of sediments in aerated lagoons and waste stabilization ponds
Chabir, D.; El Ouarghi, H.; Brostaux, Yves ULg et al

in Water Science & Technology (2000), 42(10), 237-246

Respirometric tests have been undertaken on sediments in aerated lagoons and waste stabilization ponds to quantify their oxygen demand and to determine the main factors governing the process. Factors such ... [more ▼]

Respirometric tests have been undertaken on sediments in aerated lagoons and waste stabilization ponds to quantify their oxygen demand and to determine the main factors governing the process. Factors such as seasonal variations, temperature, substrate, sediment layer thickness, density of macro-invertebrates and suspended sediments were investigated. The results showed that temperature and substrate concentration are the main factors that influence sediment oxygen demand; followed by spatial heterogeneity and resuspension of sediments, whereas the density of macro-invertebrates could have an effect in summer (hot season). Sediment layer thickness had no effect. A model of sediment oxygen demand is developed for the two main factors (temperature and substrate) with an r2 of 0.98. [less ▲]

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See detailWater and nitrogen transfer study through soils of a small agricultural water catchment
Tychon, Bernard ULg; Vander Borght, Paul ULg; De Backer, Louis W.

in Water Science & Technology (1999), 39(12), 69-76

Water and nitrogen movements in a small watershed (32ha) located in the Belgian Lorraine (south-eastern Belgium) were monitored intensively between 1988 and 1991 to investigate at a daily time step the ... [more ▼]

Water and nitrogen movements in a small watershed (32ha) located in the Belgian Lorraine (south-eastern Belgium) were monitored intensively between 1988 and 1991 to investigate at a daily time step the possibility of predicting water discharge rates and nitrate concentrations in a spring if one knows the surface agricultural practices in the catchment area. The watershed was equipped with instruments to monitor the various meteorological, pedological, agronomic and geohydrological parameters assumed to explain most of the behaviour of water and nitrogen fluxes. They were recorded at various levels, i.e., the surface, vadose zone, saturated zone, and watershed outlet. Field observations were made to cross-check fluxes at each level. This information was then used in simulation models (SOIL and SOILN) to describe the movement of water and nitrogen solutes in the vadose zone and with original programming that describes their movements in the groundwater down to the outlet. These models present many parameters, the most sensitive of which were subjected to Monte Carlo Analysis which confirmed the robustness of the approach. The performance of the comprehensive model is quite satisfactory, with a 10% error in nitrogen fluxes over a three-year period. It shows the limits of such an approach despite the particularly intense degree of observation. [less ▲]

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See detailTreatment of gypsum waste in a two stage anaerobic reactor
Deswaef, Sophie; Salmon, Thierry ULg; Hiligsmann, Serge ULg et al

in Water Science & Technology (1996), 34(5-6), 367-374

The reduction of high concentrations of gypsum (up to 110 kg/m(3)) is investigated in a two stage immobilised cell bioreactor. The first stage is mainly colonised by a consortium of acidogenic bacteria ... [more ▼]

The reduction of high concentrations of gypsum (up to 110 kg/m(3)) is investigated in a two stage immobilised cell bioreactor. The first stage is mainly colonised by a consortium of acidogenic bacteria and sulphate reducing bacteria oxidising volatile fatty acids with more than 2 carbons (mainly, butyrate and propionate). The gypsum consumption rate is rather high (ii kg/m(3).day). Most of acetate remains unconverted in this first stage. It is partially converted in the second stage (residence time : 12 days) which is predominantly colonised by acetate oxidising bacteria The gypsum consumption rate is much lower than in the first stage : 3 kg/m(3).day. With both stages, it is possible to reach an almost complete conversion of gypsum with an overall capacity of 6.1 kg gypsum/m(3).day. We propose also a very simple model to describe the different transformation rates. It allows us to clearly identify the activity levels of the different types of sulphate reducing bacteria in both stages. Copyright (C) 1996 IAWQ. [less ▲]

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See detailInteractions between the biofilm growth and the hydrodynamics in an aerobic trickling filter
Lekhlif, B.; Toye, Dominique ULg; Marchot, Pierre ULg et al

in Water Science & Technology (1994), 29

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See detailEvaluation of the performances of random plastic media in aerobic trickling filters
Crine, Michel ULg; Schlitz, Marc; L'Homme, Guy ULg

in Water Science & Technology (1990), 22

Detailed reference viewed: 18 (3 ULg)