The fate and importance of organics in drinking water treatment: a review

Abstract

In the pioneer days, the main driving forces for research of organics in drinking water treatment (DWT) were human health risks and optimisation of technology. The focus was on natural organic matter (NOM) structure, disinfection by-products (DBPs) formation, NOM removal by means of coagulation, adsorption, and oxidation, and development of the most efficient water treatment trains. Surprisingly, after decades of research, rapid development of analytical techniques and progress in risk assessment, the same driving forces are still in the limelight - although the topics have changed slightly. The attention switched from trihalomethanes to a new generation of DBPs. The definition of hydrophilic/hydrophobic NOM depends on the technique used for characterisation. It has become evident that numerous organic compounds can threaten water supply sources. Some of them had been ignored or overlooked in the past, but have recently been detected by advanced analytical tools even in drinking water. Prioritisation becomes priority per se. As far as processes are concerned, mainstream research has been following three lines: fouling mechanisms, application of hybrid processes and interactions between synthetic organic chemicals, other water constituents and materials used in DWT. Significant development has been made in membrane technology. This paper presents a broad overview of the recent organics research. Although the state-of-the-art technologies seem to have an answer to each and every question raised, it is still necessary to deal with specific problems on a case-by-case basis mainly due to the unique nature of NOM and different xenobiotics that may appear in various types of waters. In the end, human health risk, which derives from the presence/absence of organics, is only the tip of the iceberg - underneath lies a whole new universe - the socio-economic aspect of water treatment and quality that deserves much more attention.

Predicting the reaction rate constants of micropollutants with hydroxyl radicals in water using QSPR modeling

“…Although their health effects are mostly unknown, the removal of these micropollutants from drinking water has been of concern to water utilities and environmental agencies due to the precautionary principle. Advanced treatment technologies such as advanced oxidation processes (AOPs), reverse osmosis, and nanofiltration have demonstrated effectiveness in removing micropollutants (Ivančev-Tumbas, 2014 q Note: The majority of the study was completed at the University of Waterloo.…”

Preparation of lignosulfonate–acrylamide–chitosan ternary graft copolymer and its flocculation performance

“…Hence, removal of toxic materials in the wastewater becomes a serious challenge [1][2][3][4]. Various traditional and advanced technologies have been employed to remove the particles, dissolved metal ions and other toxic materials from wastewater, such as ion exchange, membrane filtration, precipitation, solvent extraction, flocculation, biodegradation and catalytic oxidation [5][6][7][8][9][10][11].…”

A selection framework for NOM removal process for drinking water treatment

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