scholarly journals First Derivative UV Spectra of Surface Water as a Monitor of Chlorination in Drinking Water Treatment

2001 ◽  
Vol 1 ◽  
pp. 39-43 ◽  
Author(s):  
V. Zitko
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Surface Water ◽  
Distribution System ◽  
Drinking Water Treatment ◽  
Uv Spectra ◽  
Free Chlorine ◽  
Residual Chlorine ◽  
First Derivative ◽  
Derivative Spectra

Many countries require the presence of free chlorine at about 0.1 mg/l in their drinking water supplies. For various reasons, such as cast-iron pipes or long residence times in the distribution system, free chlorine may decrease below detection limits. In such cases it is important to know whether or not the water was chlorinated or if nonchlorinated water entered the system by accident. Changes in UV spectra of natural organic matter in lakewater were used to assess qualitatively the degree of chlorination in the treatment to produce drinking water. The changes were more obvious in the first derivative spectra. In lakewater, the derivative spectra have a maximum at about 280 nm. This maximum shifts to longer wavelengths by up to 10 nm, decreases, and eventually disappears with an increasing dose of chlorine. The water treatment system was monitored by this technique for over 1 year and changes in the UV spectra of water samples were compared with experimental samples treated with known amounts of chlorine. The changes of the UV spectra with the concentration of added chlorine are presented. On several occasions, water, which received very little or no chlorination, may have entered the drinking water system. The results show that first derivative spectra are potentially a tool to determine, in the absence of residual chlorine, whether or not surface water was chlorinated during the treatment to produce potable water.

Characterization of NOM in a drinking water treatment process train with no disinfectant residual

2009 ◽  
Vol 9 (4) ◽  
pp. 379-386 ◽  
Author(s):  
S. A. Baghoth ◽  
M. Dignum ◽  
A. Grefte ◽  
J. Kroesbergen ◽  
G. L. Amy
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Organic Carbon ◽  
Distribution System ◽  
Chemical Properties ◽  
Drinking Water Treatment ◽  
Building Blocks ◽  
Fluorescence Excitation ◽  
Water Treatment Process ◽  
Water Treatment Plants

For drinking water treatment plants that do not use disinfectant residual in the distribution system, it is important to limit availability of easily biodegradable natural organic matter (NOM) fractions which could enhance bacterial regrowth in the distribution system. This can be achieved by optimising the removal of those fractions of interest during treatment; however, this requires a better understanding of the physical and chemical properties of these NOM components. Fluorescence excitation-emission matrix (EEM) and liquid chromatography with online organic carbon detection (LC-OCD) were used to characterize NOM in water samples from one of the two water treatment plants serving Amsterdam, The Netherlands. No disinfectant residual is applied in the distribution system. Fluorescence EEM and LC-OCD were used to track NOM fractions. Whereas fluorescence EEM shows the reduction of humic-like as well as protein-like fluorescence signatures, LC-OCD was able to quantify the changes in dissolved organic carbon (DOC) concentrations of five NOM fractions: humic substances, building blocks (hydrolysates of humics), biopolymers, low molecular weight acids and neutrals.

scholarly journals Genotoxicity of source, treated and distributed water from four drinking water treatment plants supplied by surface water in Sardinia, Italy

2020 ◽  
Vol 185 ◽  
pp. 109385 ◽  
Author(s):  
Donatella Feretti ◽  
Mattia Acito ◽  
Marco Dettori ◽  
Elisabetta Ceretti ◽  
Cristina Fatigoni ◽  
...  
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Surface Water ◽  
Drinking Water Treatment ◽  
Water Treatment Plants

scholarly journals After the flood: an evaluation of in-home drinking water treatment with combined flocculent-disinfectant following Tropical Storm Jeanne — Gonaives, Haiti, 2004

2007 ◽  
Vol 5 (3) ◽  
pp. 367-374 ◽  
Author(s):  
Romulo E. Colindres ◽  
Seema Jain ◽  
Anna Bowen ◽  
Eric Mintz ◽  
Polyana Domond
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Drinking Water Treatment ◽  
Water Sources ◽  
Tropical Storm ◽  
Coliform Bacteria ◽  
Residual Chlorine ◽  
Household Water ◽  
Untreated Water ◽  
Local Leaders

Tropical Storm Jeanne struck Haiti in September 2004, causing widespread flooding which contaminated water sources, displaced thousands of families and killed approximately 2,800 people. Local leaders distributed PūR®, a flocculent-disinfectant product for household water treatment, to affected populations. We evaluated knowledge, attitudes, practices, and drinking water quality among a sample of PūR® recipients. We interviewed representatives of 100 households in three rural communities who received PūR® and PūR®-related education. Water sources were tested for fecal contamination and turbidity; stored household water was tested for residual chlorine. All households relied on untreated water sources (springs [66%], wells [15%], community taps [13%], and rivers [6%]). After distribution, PūR® was the most common in-home treatment method (58%) followed by chlorination (30%), plant-based flocculation (6%), boiling (5%), and filtration (1%). Seventy-eight percent of respondents correctly answered five questions about how to use PūR®; 81% reported PūR® easy to use; and 97% reported that PūR®-treated water appears, tastes, and smells better than untreated water. Although water sources tested appeared clear, fecal coliform bacteria were detected in all sources (range 1 – >200 cfu/100 ml). Chlorine was present in 10 (45%) of 22 stored drinking water samples in households using PūR®. PūR® was well-accepted and properly used in remote communities where local leaders helped with distribution and education. This highly effective water purification method can help protect disaster-affected communities from waterborne disease.

scholarly journals The Dutch secret: safe drinking water without chlorine in the Netherlands

2008 ◽  
Vol 1 (2) ◽  
pp. 173-212 ◽  
Author(s):  
P. W. M. H. Smeets ◽  
G. J. Medema ◽  
J. C. van Dijk
Keyword(s):  
Drinking Water ◽  
Surface Water ◽  
The Netherlands ◽  
Distribution System ◽  
Drinking Water Treatment ◽  
Quantitative Microbial Risk Assessment ◽  
Safe Drinking Water ◽  
Microbial Risk Assessment ◽  
Production And Distribution ◽  
Water Companies

Abstract. The Netherlands is one of the few countries where chlorine is not used at all, neither for primary disinfection nor to maintain a residual disinfectant in the distribution network. The Dutch approach that allows production and distribution of drinking water without the use of chlorine while not compromising microbial safety at the tap, can be summarized as follows: Use the best source available, in order of preference: – microbiologically safe groundwater, – surface water with soil passage such as artificial recharge or bank filtration, – direct treatment of surface water in a multiple barrier treatment; Use a preferred physical process treatment such as sedimentation, filtration and UV-disinfection. If absolutely necessary, also oxidation by means of ozone or peroxide can be used, but chlorine is avoided; Prevent ingress of contamination during distribution; Prevent microbial growth in the distribution system by production and distribution of biologically stable (biostable) water and the use of biostable materials; Monitor for timely detection of any failure of the system to prevent significant health consequences. New developments in safe drinking water in the Netherlands include the adaptation of the Dutch drinking water decree, implementation of quantitative microbial risk assessment (QMRA) by water companies and research into source water quality, drinking water treatment efficacy, safe distribution and biostability of drinking water during distribution and \\textit{Legionella}. This paper summarizes how the Dutch water companies warrant the safety of the drinking water without chlorine.

scholarly journals Oxidation of Selected Trace Organic Compounds through the Combination of Inline Electro-Chlorination with UV Radiation (UV/ECl2) as Alternative AOP for Decentralized Drinking Water Treatment

Water ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3275
Author(s):  
Philipp Otter ◽  
Katharina Mette ◽  
Robert Wesch ◽  
Tobias Gerhardt ◽  
Frank-Marc Krüger ◽  
...  
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Organic Compounds ◽  
Energy Input ◽  
Drinking Water Treatment ◽  
Pilot Scale ◽  
Residual Chlorine ◽  
Trace Organic Compounds ◽  
Drinking Water Standard ◽  
Trace Organic

A large variety of Advanced Oxidation Processes (AOPs) to degrade trace organic compounds during water treatment have been studied on a lab scale in the past. This paper presents the combination of inline electrolytic chlorine generation (ECl2) with low pressure UV reactors (UV/ECl2) in order to allow the operation of a chlorine-based AOP without the need for any chlorine dosing. Lab studies showed that from a Free Available Chlorine (FAC) concentration range between 1 and 18 mg/L produced by ECl2 up to 84% can be photolyzed to form, among others, hydroxyl radicals (OH) with an UV energy input of 0.48 kWh/m3. This ratio could be increased to 97% by doubling the UV energy input to 0.96 kWh/m3 and was constant throughout the tested FAC range. Also the achieved radical yield of 64% did not change along the given FAC concentration range and no dependence between pH 6 and pH 8 could be found, largely simplifying the operation of a pilot scale system in drinking water treatment. Whereas with ECl2 alone only 5% of benzotriazoles could be degraded, the combination with UV improved the degradation to 89%. Similar results were achieved for 4-methylbenzotriazole, 5-methylbenzotriazole and iomeprol. Oxipurinol and gabapentin were readily degraded by ECl2 alone. The trihalomethanes values were maintained below the Germany drinking water standard of 50 µg/L, provided residual chlorine concentrations are kept within the permissible limits. The here presented treatment approach is promising for decentralized treatment application but requires further optimization in order to reduce its energy requirements.

Estradiol Uptake in a Combined Magnetic Ion Exchange - Ultrafiltration (MIEX-UF) Process During Water Treatment

2017 ◽  
Vol 23 (2) ◽  
pp. 328-337 ◽  
Author(s):  
Alessandra Imbrogno ◽  
Jennifer Biscarat ◽  
Andrea Iris Schafer
Keyword(s):  
Drinking Water ◽  
Humic Acid ◽  
Water Treatment ◽  
Surface Water ◽  
Ion Exchange ◽  
Acid Concentration ◽  
Drinking Water Treatment ◽  
Polymeric Materials ◽  
Aquatic Life ◽  
Magnetic Ion

Background: Estrogens and their synthetic analogues are widely used as pharmaceuticals. Upon oral administration these drugs are eventually excreted via urine. The persistence of these pharmaceuticals and inefficient removal by water treatment lead to accumulation in surface water and effluents with negative effects for aquatic life and human health. Methods: In this study, the uptake of estradiol by a combined magnetic ion exchange resin - ultrafiltration process (MIEX-UF) was investigated. This is a relatively common process used in drinking water treatment for the removal of natural organic matter. However, uptake of micropollutants, such as steroidal pharmaceuticals, may occur as a side effect of water treatment due to the high affinity for polymeric materials. To elucidate the mechanism governing estradiol partitioning between water, resin and membrane, the influence of different parameters, such as pH, humic acid concentration and membrane molecular-weight-cut-off (MWCO) was studied. Results: Humic acid concentration and pH affected estradiol uptake most. At pH 11 the most significant increase of estradiol uptake was observed for MIEX-UF process (30 ng/g corresponding to 80%) compared with individual UF (17 ng/g corresponding to 12%). The presence of humic acid slightly reduced estradiol uptake at pH 11 (about 55%) due to competition for the ion exchange binding sites. Conclusion: Results demonstrated that the uptake of estradiol, which is amongst the most potent EDCs detected in surface water, in the MIEX-UF process can reach significant quantities (30 ng/g of resin) leading to uncontrolled accumulation of this micropollutant during drinking water treatment. This study gives a novel contribution in the understanding the mechanism of the unanticipated accumulation of pharmaceuticals, such as estradiol, in the drinking water treatment process.

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