Samples from the two main watersheds that provide Athens Water Supply and Sewerage Company (AWSSC) with raw water were examined for Dissolved Organic Carbon (DOC) and for their molecular weight distribution (MWD). In addition, water... more
Samples from the two main watersheds that provide Athens Water Supply and Sewerage Company (AWSSC) with raw water were examined for Dissolved Organic Carbon (DOC) and for their molecular weight distribution (MWD). In addition, water samples from water treatment plants (WTPs) and from the water supply network were examined for trihalomethane (THMs) levels. The main purpose of this study was to reveal the molecular composition of natural organic matter (NOM) and identify the individual differences between NOM from the two main Athens watersheds. High-performance size exclusion chromatography (HPSEC), a relatively simple technique, was applied to determine different NOM fractions' composition according to molecular weight. Various THM levels in the supply network of Athens are illustrated as a result of the different reservoirs' water qualities, and a suggestion for a limited application of chlorine dioxide is made in order to minimize THM formation.
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Zearalenone (ZEA) is a mycotoxin produced by some Fusarium species in food and feed. The toxicity of ZEA and its metabolites is related to the chemical structure of the mycotoxin, which is similar to naturally occurring oestrogens.... more
Zearalenone (ZEA) is a mycotoxin produced by some Fusarium species in food and feed. The toxicity of ZEA and its metabolites is related to the chemical structure of the mycotoxin, which is similar to naturally occurring oestrogens. Currently, there is increasing awareness of the presence of fungi and their toxic metabolites in the aquatic environment. One of the sources of these compounds are the effluents from wastewater treatment plants. The average annual efficiency of zearalenone reduction in the Łęczyca plant in our three-year study was in the range from 51.35 to 69.70 %. The threeway analysis of variance (year, month, and kind of wastewater) shows that the main effects of all factors and all interactions between them were significant for zearalenone and dissolved organic carbon content. Our findings suggest that wastewater is not the main source of surface water pollution with zearalenone. Future research should investigate the means to reduce ZEA and its migration from the fi...
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Zearalenone is a mycotoxin produced by some Fusarium species in food and feed. Toxicity of ZEA and its metabolites is related to the chemical structure of the mycotoxins, similar to naturally occurring estrogens. Currently, there is... more
Zearalenone is a mycotoxin produced by some Fusarium species in food and feed. Toxicity of ZEA and its metabolites is related to the chemical structure of the mycotoxins, similar to naturally occurring estrogens. Currently, there is increasing awareness of the significance of fungi and their toxic metabolites in water. Thus it was considered essential to determine the concentration of estrogenic toxin in surface waters, groundwater and wastewater in Poland. The application of ZearalaTest immunoaffinity columns for zearalenone determination by HPLC method in water samples characterized by different natural organic matter (NOM) content gave the recovery rate ranging from 74 to 86%. Obtained results showed that the natural organic micropollutants of water with low molecular masses have an effect on zearalenone recovery. Zearalenone was present in water samples in the range from 0 to 43.7 ngL(-1).
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Complex crystallographic composition of the corrosion products is studied by diffraction methods and results obtained after different pre-treatment of samples are compared. The green rusts are found to be much more abundant in corrosion... more
Complex crystallographic composition of the corrosion products is studied by diffraction methods and results obtained after different pre-treatment of samples are compared. The green rusts are found to be much more abundant in corrosion scales than it has been assumed so far. The characteristic and crystallographic composition of corrosion scales and deposits suspended in steady waters were analyzed by X-ray diffraction (XRD). The necessity of the examination of corrosion products in the wet conditions is indicated. The drying of the samples before analysis is shown to substantially change the crystallographic phases originally present in corrosion products. On sample drying the unstable green rusts is converted into more stable phases such as goethite and lepidocrocite, while the content of magnetite and siderite decreases. Three types of green rusts in wet materials sampled from tubercles are identified. Unexpectedly, in almost all corrosion scale samples significant amounts of the least stable green rust in chloride form was detected. Analysis of corrosion products suspended in steady water, which remained between tubercles and possibly in their interiors, revealed complex crystallographic composition of the sampled material. Goethite, lepidocrocite and magnetite as well as low amounts of siderite and quartz were present in all samples. Six different forms of green rusts were identified in the deposits separated from steady waters and the most abundant was carbonate green rust GR(CO(3)(2-))(I).
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Zearalenone is a non-steroidal, strongly oestrogenic substance, which can occur in food and feed. It causes functional changes in the reproductive system similar to those of oestrogens. Due to the occurrence of this toxin in agricultural... more
Zearalenone is a non-steroidal, strongly oestrogenic substance, which can occur in food and feed. It causes functional changes in the reproductive system similar to those of oestrogens. Due to the occurrence of this toxin in agricultural areas it has been assumed that it may penetrate to surface and ground waters and thus poses a health hazard both for humans and animals. We examined the occurrence of zearalenone in Polish surface and ground waters as well as in sewage during 2010 and investigated the relation between organic carbon found in samples and toxin concentration. The highest zearalenone concentration was found in samples collected from the river Bogdanka: 65.2 ng/l, in August. In addition, in all cases investigated the dissolved organic carbon concentration was found to decrease with an increase in zearalenone concentration.
Research Interests: Environmental Engineering, Chemical Engineering, Civil Engineering, Environmental Science, Water, and 12 moreWater quality, Water and wastewater treatment, Water Treatment, Wastewater Treatment, Activated carbon adsorption, Ozonation, Adsorption, Activated Carbon, Water and Wastewater, Adsorption and wastewater treatment, Ozone, and Water Quality
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The effective removal of soluble natural organic matter (NOM) during water treatment can significantly decrease the ClO(2) demand of processed water. This can be achieved through the oxidation and/or the removal of NOM. The purpose of the... more
The effective removal of soluble natural organic matter (NOM) during water treatment can significantly decrease the ClO(2) demand of processed water. This can be achieved through the oxidation and/or the removal of NOM. The purpose of the study was to examine the influence of ClO(2) oxidation and subsequent GAC filtration on the final ClO(2) demand of treated water. The study showed the ClO(2) demand to be strongly correlated with the abundance of high molecular fractions of NOM in treated water. As it was shown, this part of NOM was effectively removed during the GAC filtration. Moreover, the pre-treatment of water with ClO(2) considerably increased the total capacity of GAC filters for organic and inorganic (i.e. chlorites) oxidation by-products. Therefore, the oxidation of NOM molecules in conjunction with a very efficient GAC filtration can be successfully employed to control the abundance of high molecular NOM components, and thus the ClO(2) demand of finished water.
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Research Interests: High Pressure, Environmental Monitoring, Filtration, Ion Chromatography, Multidisciplinary, and 15 moreDrinking Water Treatment, Chlorine dioxide, Humic acid, Gas Chromatography, Ozone, Fractionation, Oxidation, Oxides, Oxidant, Chlorine Compounds, Organic Matter, Cation Exchange, Natural Organic Matter, Organic Chemicals, and Molecular Weight Distribution
Research Interests: Water, Carbon, Water Purification, Distributed System, Corrosion, and 15 moreMultidisciplinary, Water Supply, Nitrification, Diffusion, Denitrification, Bacteria, Drinking Water, Nitrates, Ammonia, Time Factors, Retention Time, Water Movements, Ferric Compounds, Nephelometry and Turbidimetry, and Sulphate Reducing Bacteria
Chemical stability of water should be high enough to ensure that the water reaching the consumers would have the same composition as at the treatment plant. The drinking water supplied by one of the water treatment plants for the city of... more
Chemical stability of water should be high enough to ensure that the water reaching the consumers would have the same composition as at the treatment plant. The drinking water supplied by one of the water treatment plants for the city of Poznań was observed to produce periodically white non-sedimenting precipitate on boiling, deteriorating its organoleptic properties. The phenomenon was found to be related to a high content of magnesium in the water taken for treatment and low content of other ions besides bicarbonates. XRD and SEM analyses have shown that a low ratio of calcium ions to magnesium ions leads to formation of calcite crystals on water boiling in which a fraction of cationic crystallographic sites are substituted with Mg(2+) ions giving (Ca(1-x)Mg(x))CO(3) crystallites. Such crystallites have smaller size than those of calcite formed on boiling water coming from other Poznań suppliers. The smaller size of the crystallites is responsible for their slower sedimentation and hence the observed increase in the water turbidity on its boiling. It has been proved that the appearance of precipitates in drinking water at the consumers can be achieved by reduction of the Mg/(Mg + Ca) ratio to below 3, which would inhibit peptisation of the precipitate and prevent water opacity and/or adjustment of pH of the raw water and removal of the carbon dioxide released to convert some carbonate hardness into non-carbonate one. These measures will limit the amount of the precipitate forming upon water boiling and change its microcrystalline type into an easier sedimenting one.
Research Interests: Water, Water quality, Water Purification, Calcium, Scanning Electron Microscopy, and 13 morePoland, Multidisciplinary, Magnesium, Hardness, Chemical Precipitation, X ray diffraction, Particle Size, Water Wells, Water Quality, Calcium Carbonate, Alkalies, Water Treatment Plant, and Transition Temperature
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Research Interests: Water, Carbon, Water Purification, Water Treatment, Filtration, and 14 moreMultidisciplinary, Adsorption, Chlorine dioxide, Total Organic Carbon, Molecular weight, Oxides, Chlorine Compounds, Granular Activated Carbon, Oxidation-Reduction, Natural Organic Matter, Organic Chemicals, Size Exclusion Chromatography, Molecular Weight Distribution, and Low molecular weight
ABSTRACT This article presents the results obtained for humic acid (HA) degradation in drinking water by means of an ozonation process in the presence of a nonpolar bonded alumina phase. It was observed that (perflurooctylalumina) (PFOA)... more
ABSTRACT This article presents the results obtained for humic acid (HA) degradation in drinking water by means of an ozonation process in the presence of a nonpolar bonded alumina phase. It was observed that (perflurooctylalumina) (PFOA) is characterized by its high adsorption capacity toward HA. The adsorption properties of bare alumina and alumina modified with perfluorooctanoic acid appeared to differ significantly toward the various organic substances examined. The ozonation process carried out in the presence of PFOA was found to be more efficient for the removal of HA from water than the other two examined ozonation systems: ozonation alone and ozonation in the presence of bare alumina; however, a catalytic activity of bare alumina cannot be denied. The effect of by-products formation and changes in the molecular size distribution of HA were studied in the case of all three examined ozonation systems. The influence of catalyst dosage and ozonation time was also investigated.
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ABSTRACT The influence of ozonation conditions (i.e. ozone dose and contact time) on the aldehyde and carboxylic acids formation was studied on a pilot scale. The data derived from changes in the molecular weight distribution of natural... more
ABSTRACT The influence of ozonation conditions (i.e. ozone dose and contact time) on the aldehyde and carboxylic acids formation was studied on a pilot scale. The data derived from changes in the molecular weight distribution of natural organic matter (NOM) and the concentration of residual ozone can be applied to a selection of the optimum ozonation conditions. The results confirm the relative ease with which ozone reacts with the organic matter. The short contact time (4–6 min) appeared to be sufficient for the reaction. The higher molecular weight (1600 D) fraction of NOM seems to be slightly more reactive to ozone than the lower molecular weight fraction (500 D). It was also observed that carboxylic acids had been formed at much higher quantities than aldehydes. Two differently acting groups of aldehydes were identified. The concentration of the first one (i.e. formaldehyde, acetaldehyde) strongly depends on ozone dose, while the concentration of the second group of aldehydes (i.e. glyoxal, methylglyoxal) seems to be relatively independent of the ozone dose.
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... Pub-lished on the NRC Research Press Web site at http://jees.nrc.ca/ on 23 December 2003. B. Kasprzyk-Hordern, A. Dabrowska, J. Swietlik, and J. Nawrocki.1 Department of Water Treatment Technology, Fac-ulty of Chemistry, Adam... more
... Pub-lished on the NRC Research Press Web site at http://jees.nrc.ca/ on 23 December 2003. B. Kasprzyk-Hordern, A. Dabrowska, J. Swietlik, and J. Nawrocki.1 Department of Water Treatment Technology, Fac-ulty of Chemistry, Adam Mickiewicz University, ul. ...
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The paper reports results of the experiments carried out at Fortore (Foggia, South Italy) and Mosina (Poznan, Poland) drinking water treatment plants aimed at DBPs control. Pilot scale GAC filters were installed in both plants in order to... more
The paper reports results of the experiments carried out at Fortore (Foggia, South Italy) and Mosina (Poznan, Poland) drinking water treatment plants aimed at DBPs control. Pilot scale GAC filters were installed in both plants in order to assess the efficacy of different kind of GAC for chlorites, NOM and THMs removal. Both pilot plants operated with and without chlorine dioxide pre-disinfection. In Fortore plant, because of free chlorine was added in ClO2 pre‐disinfection solution, THMs formation was evaluated. Results showed an high efficacy of chlorites removal on GAC filters up to 5500 and 10000 bed volumes for mineral and vegetal GAC in Fortore and up to 11000 bed volumes in Mosina. A preliminary characterization of natural organic matter (NOM) dissolved in Fortore raw water was performed as well, in order to confirm its reactivity towards chlorine dioxide. The presence of small molecules (< 500 Da) in Fortore pre‐disinfected water, has resulted in THMs and carboxylic acids ...
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Oxidation is well-known process of transforming natural organic matter during the treatment of drinking water. Chlorine, ozone, and chlorine dioxide are common oxidants used in water treatment technologies for this purpose. We studied the... more
Oxidation is well-known process of transforming natural organic matter during the treatment of drinking water. Chlorine, ozone, and chlorine dioxide are common oxidants used in water treatment technologies for this purpose. We studied the influence of different doses of these oxidants on by-products formation and changes in biodegradable dissolved organic carbon (BDOC) and molecular weight distribution (MWD) of fulvic acids (FA) with different BDOC content. Chlorination did not significantly change the MWD of FA and disinfection by-products formation. However, higher molecular weight compounds, than those in the initial FA, were formed. It could be a result of chlorine substitution into the FA structure. Chlorine dioxide oxidized FA stronger than chlorine. During ozonation of FA, we found the highest increase of BDOD due to the formation of a high amount of organic acids and aldehydes. FA molecules were transformed into a more biodegradable form. Ozonation is the most preferable process among those observed for pre-treatment of FA before biofiltration.