Overview of Drinking Water Treatment Processes

Owing to the nature of the treatment processes, monitoring the processes based on individual online measurements is difficult or even impossible. However, the measurements (online and laboratory) can be combined with a priori process knowledge, using mathematical models, to objectively monitor the treatment processes and measurement devices. The pH measurement is a commonly used measurement at different stages in the drinking water treatment plant, although it is a unreliable instrument, requiring significant maintenance. It is shown that, using a grey-box model, it is possible to assess the measurement devices effectively, even if detailed information of the specific processes is unknown.

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Enhanced effectiveness of medium-pressure ultraviolet lamps on human adenovirus 2 and its possible mechanism

Water Science & Technology ◽

10.2166/wst.2009.414 ◽

2009 ◽

Vol 60 (4) ◽

pp. 851-857 ◽

Cited By ~ 17

Author(s):

Gwy-Am Shin ◽

Jung-Keun Lee ◽

Karl G. Linden

Keyword(s):

Drinking Water ◽

Water Treatment ◽

Human Exposure ◽

Drinking Water Treatment ◽

Human Adenovirus ◽

Repair Process ◽

Uv Disinfection ◽

Medium Pressure ◽

Treatment Processes ◽

Uv Technology

There has been growing concern over human exposure to adenoviruses through drinking water due to their apparent high resistance to UV irradiation and the anticipated widespread use of ultraviolet (UV) disinfection in drinking water treatment processes. However, most inactivation studies on adenoviruses were performed using only one type of UV technology—low-pressure (LP) UV, and little is known about the effectiveness of different UV technologies such as medium- pressure (MP) UV or other polychromatic UV technologies. In this work, the kinetics and extent of inactivation of a human adenovirus (adenovirus 2 (Ad2)) by both monochromatic LP and polychromatic MP UV were evaluated to determine the effectiveness of these UV technologies on human adenoviruses. Inactivation of Ad2 by LP UV was very slow and only 0.87 and 2.17 log10 inactivation was achieved with UV doses of 30 and 90 mJ/cm2, respectively. However, inactivation of Ad2 by MP UV was much faster and 2.19 and 5.36 log10 inactivation was observed with the same UV doses (30 and 90 mJ/cm2, respectively). It appears that MP UV is more effective against Ad2 than LP UV and the enhanced effectiveness of MP UV on Ad2 is likely due to its ability to inhibit the repair process in UV-irradiated Ad2.

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Ozone and UV – a tool for multi-barrier concepts in water treatment

Water Science & Technology Water Supply ◽

10.2166/ws.2006.913 ◽

2006 ◽

Vol 6 (4) ◽

pp. 17-25 ◽

Cited By ~ 1

Author(s):

A. Ried ◽

J. Mielcke

Keyword(s):

Drinking Water ◽

Wastewater Treatment ◽

Activated Carbon ◽

Water Treatment ◽

Biological Treatment ◽

Municipal Wastewater ◽

Drinking Water Treatment ◽

Additional Treatment ◽

Municipal Wastewater Treatment ◽

Treatment Processes

The use of ozone and/or UV for water treatment processes is often a combination of an ozone and/or UV-step with additional treatment steps, e.g. biological treatment, flocculation, filtration and activated carbon. Therefore, it is necessary to develop an optimized combination of these different steps. This article will demonstrate the advantages presenting two examples for drinking water treatment and two examples for municipal wastewater treatment.

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Removal of radio N-nitrosodimethylamine (NDMA) from drinking water by coagulation and Powdered Activated Carbon (PAC) adsorption

Drinking Water Engineering and Science Discussions ◽

10.5194/dwesd-2-79-2009 ◽

2009 ◽

Vol 2 (1) ◽

pp. 79-100 ◽

Cited By ~ 1

Author(s):

J. Chung ◽

Y. Yoon ◽

M. Kim ◽

S.-B. Lee ◽

H.-J. Kim ◽

...

Keyword(s):

Drinking Water ◽

Activated Carbon ◽

Water Treatment ◽

Background Electrolyte ◽

Treatment Plant ◽

Drinking Water Treatment ◽

Powdered Activated Carbon ◽

Individual Treatment ◽

Solution Ph ◽

Treatment Processes

Abstract. The presence of N-nitrosodimethylamine (NDMA) in drinking water supplies has raised concern over its removal by common drinking water treatment processes. A simple detection method based on scintillation spectroscopy has been used to quantify the concentration of 14C-labeled NDMA at various ratios of sample to scintillation liquid. Without sample pretreatment, the method detection limits are 0.91, 0.98, 1.23, and 1.45 ng/L of NDMA at scintillation intensity ratios of 10:10, 5:15, 15:5, and 2.5:17.5 (sample: scintillation liquid), respectively. The scintillation intensity in all cases is linear (R2>0.99) and is in the range of 0 to 100 ng/L of NDMA. In addition, because scintillation intensity is independent of solution pH, conductivity, and background electrolyte ion types, a separate calibration curve is unnecessary for NDMA samples at different solution conditions. Bench-scale experiments were performed to simulate individual treatment processes, which include coagulation and adsorption by powdered activated carbon (PAC), as used in a drinking water treatment plant, and biosorption, a technique used in biological treatment of waste water. The commonly used coagulation process for particulate control and biosorption is ineffective for removing NDMA (<10% by coagulation and <20% by biosorption). However, high doses of PAC may be applied to remove NDMA.

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