Influence of Humic Substance Alteration during Soil Passage on their Treatment Behaviour

1999 ◽  
Vol 40 (9) ◽  
pp. 231-239 ◽  
Author(s):  
M. Gerlach ◽  
R. Gimbel
Keyword(s):  
Water Treatment ◽  
Humic Substances ◽  
Humic Substance ◽  
Transport Phenomena ◽  
Bank Filtration ◽  
Humic Matter ◽  
Colloidal Transport ◽  
Surface Water Treatment ◽  
Coated Surfaces ◽  
Underground Passage

Humic substances are not major objectives of water treatment in drinking water supply. But, as they often influence the treatment efficiency or participate in treatment reactions, their behaviour in the treatment process can significantly determine the process design. A very effective pretreatment step can be achieved by soil passage (e. g. bank filtration or slow sand filtration) which is usually involved in German surface water treatment processes. In this study transport phenomena of humic matter during underground passage are investigated with special attention to the alteration of their treatment behavior. In a fundamental work the deposition of humic substances was studied in a model system. Transport phenomena could mathematically be described by a filtration theory of colloidal transport. From the results of these calculations the collision efficiencies of humic substances on clean and coated surfaces can be derived. The humic substance deposition on subsurfaces is accompanied by a classification based on molecular weight. An additional alteration of dissolved humic matter due to microbiological degradation and partial resolvation of deposited humic matter was observed by passage of river water through columns containing actual soil. The alteration of dissolved organic matter during soil passage is finally characterized by its adsorption and chlorination precursor behaviour. All results confirm that bank filtration is an effective pretreatment step particulary due to the decrease in connection with improvement in treatability of humic matter.

Seasonal variations in humic substances and their reduction through water treatment processes

1994 ◽  
Vol 21 (2) ◽  
pp. 173-179 ◽  
Author(s):  
M. T. Alarcon-Herrera ◽  
J. K. Bewtra ◽  
N. Biswas
Keyword(s):  
Water Treatment ◽  
Molecular Mass ◽  
Humic Substances ◽  
Humic Substance ◽  
Seasonal Variations ◽  
Treatment Plant ◽  
Gel Permeation Chromatography ◽  
Treated Water ◽  
Gel Permeation ◽  
Chlorine Demand

The apparent molecular mass concentrations of dissolved humic substances from the Detroit River and treated water from the Windsor Water Treatment Plant were determined by gel permeation chromatography over a 1-year period. The results of this research show significant seasonal variations in humic substance concentrations and these values are influenced by the turnover of water bodies. The gel permeation chromatograms of the samples indicate that there is a gradual reduction in the concentration of humic substances during the treatment process, the greatest change occurring after coagulation-sedimentation process. In this process, 76%, 40%, and 30% of the high, intermediate, and low molecular mass compounds, respectively, were either transformed in chemical composition or removed. Other parameters such as turbidity, chlorine demand (during prechlorination), and trihalomethanes concentration in the treated water were also analyzed and there appears to be a relationship between them. When the humic substance concentrations are high, generally the turbidity, chlorine demand, and total trihalomethanes concentrations in the drinking water are also high. Key words: water treatment, humic substances, molecular mass distribution.

COMPARATIVE STUDY ON SURFACE WATER TREATMENT USING ALUMINIUM SULPHATE AND POLYALUMINIUM CHLORIDES AS COAGULANT REAGENTS

2009 ◽  
Vol 8 (4) ◽  
pp. 859-863 ◽  
Author(s):  
Daniela Simina Stefan ◽  
Cristina Costache ◽  
Viorica Ruxandu ◽  
Monica Balas ◽  
Mircea Stefan
Keyword(s):  
Water Treatment ◽  
Surface Water ◽  
Comparative Study ◽  
Aluminium Sulphate ◽  
Surface Water Treatment

A rapid small scale evaluation of ultrafiltration performance for surface water treatment at Alcantarilha's water treatment works (Algarve, Portugal)

2004 ◽  
Vol 4 (5-6) ◽  
pp. 199-206
Author(s):  
M. Ribau Teixeira ◽  
H. Lucas ◽  
M.J. Rosa
Keyword(s):  
Water Treatment ◽  
Membrane Fouling ◽  
Conventional Treatment ◽  
Apparent Molecular Weight ◽  
Small Scale ◽  
Hydraulic Permeability ◽  
Scale Evaluation ◽  
Surface Water Treatment ◽  
Drinking Water Production ◽  
Pre Treatment

A rapid small-scale evaluation of ultrafiltration (UF) performance with and without physical–chemical pre-treatment was performed to up-grade the conventional treatment used for drinking water production in Alcantarilha's water treatment works, Algarve, Portugal. Direct UF and pre-ozonation/coagulation/flocculation/sedimentation/UF (O/C/F/S/UF) were evaluated using polysulphone membranes of different apparent molecular weight cut-off (MWCO) (15–47 kDa). The results indicated that (i) UF is an effective barrier against microorganisms, including virus larger than 80 nm; (ii) for surface waters with low to moderate SUVA values, direct UF performance is equivalent or better than the conventional treatment in terms of residual turbidity, while UV254 nm and TOC residuals require the use of O/C/F/S/UF; (iii) the permeate quality improves with the membrane apparent MWCO decrease, especially for the direct UF, although the conventional treatment performance is never reached using UF; (iv) membrane fouling and adsorption phenomena are more severe in direct UF than in O/C/F/S/UF sequence (pre-ozonation decreases the membrane foulants by decreasing their hydrophobicity) and these phenomena increase with the membrane hydraulic permeability and, particularly, with the membrane apparent MWCO.

Water Treatment Considerations–Aquatic Humus

1983 ◽  
Vol 15 (S2) ◽  
pp. 95-101 ◽  
Author(s):  
E T Gjessing
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Humic Substances ◽  
Health Effects ◽  
Surface Waters ◽  
Cold Climate ◽  
Treatment Processes ◽  
Aquatic Humus ◽  
Treatment Considerations

For several reasons the surface waters in cold climate areas are coloured due to humic substances. There are two major objections against humus in drinking water, the first is concerned with aesthetical and practical problems and the second is due to indirect negative health effects. There are essentially three different methods in use today for the removal or reduction of humus colour in water: (1) Addition of chemicals with the intention of reducing the “solubility”, (2) Addition of chemicals in order to bleach or mineralize the humus, and (3) Filtration with the intention of removal of coloured particles and some of the “soluble” colour. The treatment processes are discussed.

scholarly journals The Role of Catalytic Ozonation Processes on the Elimination of DBPs and Their Precursors in Drinking Water Treatment

Catalysts ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 521
Author(s):  
Fernando J. Beltrán ◽  
Ana Rey ◽  
Olga Gimeno
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Humic Substances ◽  
Hypochlorous Acid ◽  
Drinking Water Treatment ◽  
Disinfection Byproducts ◽  
Catalytic Ozonation ◽  
Operating Conditions ◽  
Halogen Compounds ◽  
Radiation Sources

Formation of disinfection byproducts (DBPs) in drinking water treatment (DWT) as a result of pathogen removal has always been an issue of special attention in the preparation of safe water. DBPs are formed by the action of oxidant-disinfectant chemicals, mainly chlorine derivatives (chlorine, hypochlorous acid, chloramines, etc.), that react with natural organic matter (NOM), mainly humic substances. DBPs are usually refractory to oxidation, mainly due to the presence of halogen compounds so that advanced oxidation processes (AOPs) are a recommended option to deal with their removal. In this work, the application of catalytic ozonation processes (with and without the simultaneous presence of radiation), moderately recent AOPs, for the removal of humic substances (NOM), also called DBPs precursors, and DBPs themselves is reviewed. First, a short history about the use of disinfectants in DWT, DBPs formation discovery and alternative oxidants used is presented. Then, sections are dedicated to conventional AOPs applied to remove DBPs and their precursors to finalize with the description of principal research achievements found in the literature about application of catalytic ozonation processes. In this sense, aspects such as operating conditions, reactors used, radiation sources applied in their case, kinetics and mechanisms are reviewed.

RHEOLOGICAL PROPERTIES OF HUMIC SUBSTANCES OF PEAT AND BROWN COAL

2021 ◽  
pp. 169-174
Author(s):  
Ivan I. Lishtvan ◽  
Vera N. Aleinikova
Keyword(s):  
Rheological Properties ◽  
Humic Substances ◽  
Structure Formation ◽  
Humic Substance ◽  
Brown Coal ◽  
Oil Wells ◽  
Alkaline Media ◽  
Rheological Parameters ◽  
Acid Media ◽  
Brown Coals

Knowledge about structure and rheological peculiarities of drilling solutions and reagents applied for the proceeding of oil wells has significant value for the forecasting of oil wells drilling. The research results of the structure of the humic substances of peat and brown coals precipitated in different pH ranges from the standpoint of their ability to structure formation on the base of the rheological curves obtaining of the flow of their dispersions and determining of their rheological parameters in terms of their application in drilling practice are given in the article. It is established that during transition from fraction, beset into alkaline media (12.0–8.5) to fraction beset into acid media (5.0–2.0) the decrease of the rheological indicators of caustobiolate humic substance is occurred. Rheological curves of the flow of the disperse of caustobiolate humic substances of the fraction 1 and 2 are characterized for strong fossil structures, disperses of humic substances of the fraction 3 is for less strong coagulation structures. Less structured are humic substances of brown coal so that their use is preferable for the regulation of the structure and rheological peculiarities of drilling solutions.

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