Treatment of trace organics in membrane concentrates I: pesticide elimination

The objective of this study was to eliminate organic micropollutants in the membrane system concentrates, which is produced by drinking water production plants, in order to protect existing water resources. This work is divided into two parts, pesticide elimination (I) and natural organic matter removal (II) in membrane system concentrates. Seven commonly detected pesticides in French surface waters, i.e. atrazine, sulcotrione, bentazone, isoproturon, diuron, glyphosate and acetochlore, were selected as the model micropollutants. Removal/degradation of these pesticides was studied by testing conventional processes employed for potable water production, i.e. adsorption, oxidation by ozone and clarification. Only partial removal of these pesticides was achieved with conventional processes. Removal of nonpolar pesticides was obtained by adsorption and rapid degradation of most of the pesticides was observed with low ozone dosages, except for atrazine and its metabolites. On the other hand, only the phosphonate-based pesticides were removed by clarification. By combining these processes, however, almost complete removal of the selected pesticides was achieved. Simultaneous ozonation and adsorption in the same reactor seems to be the most promising option for this study.

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The role of pH on the ultrafiltration for drinking water production in Algarve (Portugal)

Water Science & Technology Water Supply ◽

10.2166/ws.2002.0192 ◽

2002 ◽

Vol 2 (5-6) ◽

pp. 367-371 ◽

Cited By ~ 1

Author(s):

M. Ribau Teixeira ◽

H. Lucas ◽

M.J. Rosa

Keyword(s):

Drinking Water ◽

Organic Matter ◽

Natural Organic Matter ◽

Surface Waters ◽

Membrane Fouling ◽

Electrostatic Repulsion ◽

Water Production ◽

Ph Values ◽

Drinking Water Production

The effect of the pH on the ultrafiltration performance of natural surface waters with moderate NOM content was evaluated at a laboratory scale using a plate-and-frame polysulphone membrane of 47 kDa MWCO. The results at three different pH values (acid, neutral and basic) demonstrated the important role of the pH on the ultrafiltration (UF) performance controlling the membrane - fouling matter interactions. The higher fluxes and lower natural organic matter (NOM) rejections obtained, at basic pH when compared to acid pH, are explained in terms of the variation of membrane and NOM charge, due to electrostatic repulsion and adsorption effects.

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Coagulation/flocculation/ultrafiltration for natural organic matter removal in drinking water production

Water Science & Technology Water Supply ◽

10.2166/ws.2004.0111 ◽

2004 ◽

Vol 4 (5-6) ◽

pp. 215-222 ◽

Cited By ~ 2

Author(s):

A.R. Costa ◽

M.N. de Pinho

Keyword(s):

Drinking Water ◽

Organic Matter ◽

Natural Organic Matter ◽

Membrane Fouling ◽

Membrane Filtration ◽

Membrane Surface ◽

Water Production ◽

Cellulose Acetate Membranes ◽

Wide Range ◽

Drinking Water Production

Membrane fouling by natural organic matter (NOM), namely by humic substances (HS), is a major problem in water treatment for drinking water production using membrane processes. Membrane fouling is dependent on membrane morphology like pore size and on water characteristics namely NOM nature. This work addresses the evaluation of the efficiency of ultrafiltration (UF) and Coagulation/Flocculation/UF performance in terms of permeation fluxes and HS removal, of the water from Tagus River (Valada). The operation of coagulation with chitosan was evaluated as a pretreatment for minimization of membrane fouling. UF experiments were carried out in flat cells of 13.2×10−4 m2 of membrane surface area and at transmembrane pressures from 1 to 4 bar. Five cellulose acetate membranes were laboratory made to cover a wide range of molecular weight cut-off (MWCO): 2,300, 11,000, 28,000, 60,000 and 75,000 Da. Severe fouling is observed for the membranes with the highest cut-off. In the permeation experiments of raw water, coagulation prior to membrane filtration led to a significant improvement of the permeation performance of the membranes with the highest MWCO due to the particles and colloidal matter removal.

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Dissolved air flotation in drinking water production

Water Science & Technology ◽

10.2166/wst.2001.0453 ◽

2001 ◽

Vol 43 (8) ◽

pp. 9-18 ◽

Cited By ~ 19

Author(s):

T. Schofield

Keyword(s):

Drinking Water ◽

Water Treatment ◽

Potable Water ◽

Water Production ◽

Process Technology ◽

Dissolved Air Flotation ◽

Drinking Water Production ◽

Air Flotation ◽

Potable Water Treatment ◽

Dissolved Air

Dissolved Air Flotation (DAF) has become increasingly important in the field of potable water treatment, as a preferred option for treating upland and stored lowland waters. This paper outlines the development of dissolved air flotation (DAF) in potable water treatment, the benefits and disadvantages and the recent advances that has taken the process technology from an art to a science.

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Seasonal Dynamics in the Number and Composition of Coliform Bacteria in Drinking Water Reservoirs

10.1101/2021.02.16.428560 ◽

2021 ◽

Author(s):

Carolin Reitter ◽

Heike Petzoldt ◽

Andreas Korth ◽

Felix Schwab ◽

Claudia Stange ◽

...

Keyword(s):

Climate Change ◽

Drinking Water ◽

Microbial Community ◽

Water Temperature ◽

Surface Waters ◽

Coliform Bacteria ◽

List Type ◽

Water Production ◽

Water Reservoirs ◽

Drinking Water Production

AbstractWorldwide, surface waters like lakes and reservoirs are one of the major sources for drinking water production, especially in regions with water scarcity. In the last decades, they have undergone significant changes due to climate change. This includes not only an increase of the water temperature but also microbiological changes. In recent years, increased numbers of coliform bacteria have been observed in these surface waters. In our monitoring study we analyzed two drinking water reservoirs (Klingenberg and Kleine Kinzig Reservoir) over a two-year period in 2018 and 2019. We detected high numbers of coliform bacteria up to 2.4 x 104 bacteria per 100 ml during summer months, representing an increase of four orders of magnitude compared to winter. Diversity decreased to one or two species that dominated the entire water body, namely Enterobacter asburiae and Lelliottia spp., depending on the reservoir. Interestingly, the same, very closely related strains have been found in several reservoirs from different regions. Fecal indicator bacteria Escherichia coli and enterococci could only be detected in low concentrations. Furthermore, fecal marker genes were not detected in the reservoir, indicating that high concentrations of coliform bacteria were not due to fecal contamination. Microbial community revealed Frankiales and Burkholderiales as dominant orders. Enterobacterales, however, only had a frequency of 0.04% within the microbial community, which is not significantly affected by the extreme change in coliform bacteria number. Redundancy analysis revealed water temperature, oxygen as well as nutrients and metals (phosphate, manganese) as factors affecting the dominant species. We conclude that this sudden increase of coliform bacteria is an autochthonic process that can be considered as a mass proliferation or “coliform bloom” within the reservoir. It is correlated to higher water temperatures in summer and is therefore expected to occur more frequently in the near future, challenging drinking water production.HighlightsColiform bacteria proliferate in drinking water reservoirs to values above 104 per 100 mlThe genera Lelliottia and Enterobacter can form these “coliform blooms”Mass proliferation is an autochthonic process, not related to fecal contaminationsIt is related to water temperature and appears mainly in summerIt is expected to occur more often in future due to climate changeGraphical abstract

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Methodological Foundation and Assessment of Artesian Water Treatment Technology in the Republic of the Union Of Myanmar

Ecology and Industry of Russia ◽

10.18412/1816-0395-2021-8-34-39 ◽

2021 ◽

Vol 25 (8) ◽

pp. 34-39

Author(s):

Maung Lin Maung ◽

Htet Aung ◽

Saw Thurain ◽

D.V. Parusov ◽

G.G. Kagramanov ◽

...

Keyword(s):

Potable Water ◽

Water Production ◽

Treatment Technology ◽

Underground Waters ◽

Methodological Foundation ◽

Technical And Economic Analysis ◽

Drinking Water Production ◽

The Republic ◽

High Degree ◽

Iron And Manganese

The analysis of the compositions of artesian waters from the Republic of the Union of Myanmar as a source of potable water production is carried out. The underground waters are characterized by high degree of hardness and content of iron and manganese. Total dissolved solids (TDS) concentration corresponding thus to the class of brackish water. Three potential approaches to the development of drinking water production technology are proposed. Technical and economic analysis of the specific operating costs for potable water from artesian resources of Republic of the Union of Myanmar was carried out and the optimal technological schemes of treatment plants were determined.

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Removal of natural organic matter for drinking water production by Al/Fe-PILC-catalyzed wet peroxide oxidation: Effect of the catalyst preparation from concentrated precursors

Applied Catalysis B Environmental ◽

10.1016/j.apcatb.2011.11.004 ◽

2012 ◽

Vol 111-112 ◽

pp. 527-535 ◽

Cited By ~ 19

Author(s):

Luis Alejandro Galeano ◽

Pedro Fernando Bravo ◽

Cristian Darío Luna ◽

Miguel Ángel Vicente ◽

Antonio Gil

Keyword(s):

Drinking Water ◽

Organic Matter ◽

Natural Organic Matter ◽

Catalyst Preparation ◽

Water Production ◽

Peroxide Oxidation ◽

Wet Peroxide Oxidation ◽

Drinking Water Production ◽

Oxidation Effect

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Methodology for Determining the Presence and Origin of Organic Micropollutants

Water Science & Technology ◽

10.2166/wst.1982.0038 ◽

1982 ◽

Vol 14 (12) ◽

pp. 127-142 ◽

Cited By ~ 2

Author(s):

Alain Guiraud ◽

Joseph Larnicol

Keyword(s):

Drinking Water ◽

Liquid Chromatography ◽

Mass Spectra ◽

Treatment Process ◽

Water Production ◽

Organic Micropollutants ◽

Pragmatic Approach ◽

Physico Chemical ◽

Drinking Water Production

The article describes the approach taken by the Water Authority for the Paris Suburbs, the Compagnie Générale des Eaux and the Seine-Normandie River Basin Agency for the determination of organic micropollutants in the Oise River. The objective of the very pragmatic approach outlined is to locate the origin of possible micropollutants in the Oise water which may cause problems during treatment, distribution or consumption of the drinking water produced at the Méry-sur-Oise plant, whose treatment combines in an original way the whole range of existing processes, both the physico-chemical and the biological. The conventional method of searching for organic micropollutants consists of carrying out a series of analyses in a medium to identify a certain number of undesirable substances and of following their development in the stream. The existence of a drinking water production process, that is, a line of treatment stages, distracts from the interest in testing for a number of micropollutants, since they are removed at various stages of the treatment process. Nevertheless, the protection of reactors and, in particular, of biological reactors, requires that certain micropollutants be eliminated even before the beginning of the treatment sequence. And, among the micropollutants which might possibly enter the plant, those which should be looked at are those which will entail baneful effects for consumption, it being understood that drinking water standards are respected in all circumstances. The analytical method used is gas or liquid chromatography; where identification is essential, as in the case of suspected products, a combination of mass spectrometry and liquid chromatography is used. The notion of a chromatogram or mass spectra bank is essential. The assumption underlying the method's validity is that the discharge(s) likely to contain in large part the substances creating problems is that which usually contains them in small part. Although available experience is still limited, there are good reasons to believe that this method can improve the identification and above all the elimination of the sources of “problematic” micropollutants for the modern treatment of surface water intended for the production of drinking water.

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