Solution and Condensed Phase Characterization

1997 ◽  
Author(s):  
Roger A. Minear ◽  
Mark A. Nanny
Keyword(s):  
Drinking Water ◽  
Natural Waters ◽  
Drinking Water Treatment ◽  
Water Disinfection ◽  
Water And Wastewater Treatment ◽  
Aquatic Chemistry ◽  
Aluminum Speciation ◽  
Drinking Waters ◽  
Geochemical Significance ◽  
Aqueous Aluminum

Improvements in nuclear magnetic resonance (NMR) instrumentation, magnetic field strength, pulse sequences, and computer technology and software have increased the range of applications and specific elements available for study by NMR. The five chapters in this Part clearly indicate the benefits of these advances, especially regarding studies of aquatic, environmental significance. Each of the studies focuses on environmentally significant issues. For example, chlorination is widely used to disinfect drinking waters, a method that can produce undesirable disinfection by-products. This was first recognized in 1974 with the discovery of trihalomethanes in most finished drinking waters where hypochlorite was used for disinfection. Chapter 7 examines the chlorination of alanine and relates it to the chlorination reactions of acetaldehyde and ammonia, a topic of importance with respect to drinking water disinfection. Aluminum is also widely used in drinking water treatment, and understanding its hydrolysis chemistry and complexation behavior is of great importance to aquatic chemistry. In addition, the aquatic chemistry of aluminum is important because acid rain can release soluble aluminum ions from clay into soil water, possibly damaging terrestrial plant life. Aluminum may eventually reach and accumulate in hydrological systems where it can be toxic to aquatic life. Chapters 8 and 9 focus on 27Al NMR in defining aqueous aluminum speciation in a mildly acidic solution or in the presence of complexing organic compounds. Furthermore, aluminum is of environmental and geochemical significance since it is an integral component of clays, another ubiquitous constituent of natural waters (surface and ground). Interaction between clays, cations, and internal water molecules can be significant in understanding the fate and transport of chemicals through the environment. Since colloidal suspensions of clay materials frequently represent challenges to water and wastewater treatment, understanding of physical and chemical processes are of tantamount importance to the environmental scientist and engineer. Chapter 10 explores cation behavior in clay matrices by using “uncommon” nuclei such as 7Li, 23Na, and 133Cs as probes. This is unique in that many NMR studies of complexation in clay have focused primarily upon the nuclei 27A1 and 29Si.

DISINFEKSI UNTUK PROSES PENGOLAHAN AIR MINUM

2018 ◽  
Vol 3 (1) ◽  
Author(s):  
Nusa Idaman Said
Keyword(s):  
Drinking Water ◽  
Water Purification ◽  
Distribution System ◽  
Residual Effect ◽  
Drinking Water Treatment ◽  
Disinfection Byproducts ◽  
Water Disinfection ◽  
Pathogenic Microorganisms ◽  
Microbiological Contamination ◽  
Disinfection Process

Water disinfection means the removal, deactivation or killing of pathogenic microorganisms. Microorganisms are destroyed or deactivated, resulting in termination of growth and reproduction. When microorganisms are not removed from drinking water, drinking water usage will cause people to fall ill. Chemical inactivation of microbiological contamination in natural or untreated water is usually one of the final steps to reduce pathogenic microorganisms in drinking water. Combinations of water purification steps (oxidation, coagulation, settling, disinfection, and filtration) cause (drinking) water to be safe after production. As an extra measure many countries apply a second disinfection step at the end of the water purification process, in order to protect the water from microbiological contamination in the water distribution system. Usually one uses a different kind of disinfectant from the one earlier in the process, during this disinfection process. The secondary disinfection makes sure that bacteria will not multiply in the water during distribution. This paper describes several technique of disinfection process for drinking water treatment. Disinfection can be attained by means of physical or chemical disinfectants. The agents also remove organic contaminants from water, which serve as nutrients or shelters for microorganisms. Disinfectants should not only kill microorganisms. Disinfectants must also have a residual effect, which means that they remain active in the water after disinfection. For chemical disinfection of water the following disinfectants can be used such as Chlorine (Cl2),  Hypo chlorite (OCl-), Chloramines, Chlorine dioxide (ClO2), Ozone (O3), Hydrogen peroxide etch. For physical disinfection of water the following disinfectants can be used is Ultraviolet light (UV). Every technique has its specific advantages and and disadvantages its own application area sucs as environmentally friendly, disinfection byproducts, effectivity, investment, operational costs etc. Kata Kunci : Disinfeksi, bakteria, virus, air minum, khlor, hip khlorit, khloramine, khlor dioksida, ozon, UV.

scholarly journals Fluorine in natural waters of the Odesa region: Medicaland geographical analysis

2017 ◽  
pp. 346-357
Author(s):  
Valentina Trigub
Keyword(s):  
Drinking Water ◽  
Natural Waters ◽  
Chemical Elements ◽  
Dental Health ◽  
Fluorine Content ◽  
Drinking Waters ◽  
High Fluorine Content ◽  
Dental Diseases ◽  
Anthropogenic Loading ◽  
The City

The study of fluorine content in the natural waters of the Odesa region was carried out. The content of fluorine in the waters of the centralized and non-centralized drinking waters supply of the Odesa region and the city of Odesa is determined. Areas with low and high fluorine content are found. Very low fluorine content is determined in Kiliyskyi, Bilyaivskyi, Kodimskyi and Savranskyi districts of the Odessa region. High fluorine content (above MAC) is determined in the Tarutinskiy and Arzizkyi districts. Correlation dependence of fluorine content in drinking water of the Odesa region and indicators of the prevalence of dental diseases (caries and fluorosis of teeth) of the population of the region and the city are established. It is determined that for most districts of the region there is a relationship between the content of fluorine in drinking waters and dental health. In some areas, this dependence is not sufficiently expressed, which is due to the geochemical and ecological characteristics of the territory. It is revealed that for the population of Odesa, who use water with very low fluoride content, high indicators of the disease for caries and fluorosis of teeth are characteristic, which is connected with the allocation of industrial areas with significant anthropogenic loading, including fluorine compounds. One of the possible causes of dental disease, even with optimal fluorine content in drinking water, can be the combination of its action with other chemical elements. Key words: fluorine, drinking water, Odesa region, Odesa city, caries and fluorosis of teeth.

The Use of Aluminosilicate Sorbent for the Purification of Natural Waters from Heavy Metals

2020 ◽  
Vol 24 (3) ◽  
pp. 19-23 ◽  
Author(s):  
A.S. Kutergin ◽  
T.A. Nedobukh
Keyword(s):  
Heavy Metals ◽  
Drinking Water ◽  
Water Treatment ◽  
Mechanical Strength ◽  
Natural Waters ◽  
Drinking Water Treatment ◽  
Exchange Capacity ◽  
Filtration Process ◽  
Treated Water ◽  
Dynamic Exchange

The possibilities of using natural granular glauconite in standard water treatment schemes have been investigated. Resource tests of the studied material were carried out in dynamics, simulating possible conditions of use. As a result of the experiments, it was established: during the filtration process, alkalization of water occurs, but the result does not exceed pH = 6÷9, which are the norm for drinking water; the use of a sorbent based on natural glauconite does not impair the hardness indicator of the treated water. The dynamic exchange capacity was: for iron – 3.09 mg/g of absorbent, copper – 19.15 mg/g of absorbent, zinc – 4.82 mg/g of absorbent. The resource of the filter was determined with the loading of granulate with a volume of 1 dm3: for iron – 2918 dm3, for copper – 5425 dm3, for zinc – 273 dm3. The mechanical strength acquired by the sorbent as a result of granulation made it possible to wash the load by the countercurrent method, freeing intergranular pores from the sediment accumulated in them. The revealed capabilities of granular glauconite will allow its use in drinking water treatment schemes for purifying natural waters from heavy metals: iron, zinc, copper.

Progress on Drinking Water Treatment with Chlorine Dioxide

2013 ◽  
Vol 848 ◽  
pp. 255-258 ◽  
Author(s):  
Yu Zhong Guo ◽  
Yan Zhen Yu ◽  
Ming Li ◽  
Guang Yong Yan
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Chlorine Dioxide ◽  
Drinking Water Treatment ◽  
Water Disinfection ◽  
Water Quality Standards ◽  
Water Pretreatment ◽  
Detection Technology ◽  
Filter Water ◽  
By Products

By the reason of strong responses activity and oxidation ability, Chlorine dioxide as oxidant and disinfectant has been applied to peroxidation and disinfection more and more widely.In this paper, it give an account of the preparation of chlorine dioxide, as oxidants to raw water pretreatment, used in filter water disinfection ,the detection technology of chlorine dioxide and disinfection by-products, the water quality standards formulated by domestic and overseas chlorine dioxide in using chlorine dioxide, and summarized progress on drinking water treatment with chlorine dioxide .

Adequacy analysis of drinking water treatment technologies in regard to the parameter turbidity, considering the quality of natural waters treated by large-scale WTPs in Brazil

2019 ◽  
Vol 191 (6) ◽  
Author(s):  
Lívia Duarte Ventura Melo ◽  
Elizângela Pinheiro da Costa ◽  
Carolina Cristiane Pinto ◽  
Gabriela Rodrigues Barroso ◽  
Sílvia Corrêa Oliveira
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Large Scale ◽  
Natural Waters ◽  
Drinking Water Treatment ◽  
Treatment Technologies

scholarly journals Investigations on Temperature Effects and Germ Recovery for Solar Water Disinfection (SODIS)

2017 ◽  
Vol 4 (4) ◽  
pp. 430-435
Author(s):  
Michael Sift ◽  
Sophia Wagner ◽  
Martin Hessling
Keyword(s):  
Drinking Water ◽  
Isotonic Saline ◽  
Drinking Water Treatment ◽  
Water Disinfection ◽  
Real Surface ◽  
Large Delay ◽  
Uva Irradiation ◽  
Solar Water Disinfection ◽  
Saline Solutions ◽  
Uva Radiation

In many developing countries no infrastructure for providing people with microbiological safe drinking water exists. This demands for decentralized water disinfection that is inexpensive and requires no consumables. The casualties are often recommended the application of SODIS for drinking water treatment. There are numerous scientific studies on this disinfection method, which however are still leaving questions on the mode of functioning which is often reduced to the effect caused by the UV part of the solar radiation and there is almost no discussion in the literature what happens to the disinfected water after the SODIS treatment.In this paper disinfection experiments with Escherichia coli in isotonic saline solutions and real surface water are performed for a set of realistic conditions for UVA irradiation and for heating but separated from each other. The results confirm that SODIS is based on the combined effect of UVA radiation and increased temperature. Further experiments lead to the recommendation that once disinfected water should be consumed without a large delay, otherwise the germ concentration rises again.Int J Appl Sci Biotechnol, Vol 4(4): 430-435

Log DOW: Key to Understanding and Regulating Wastewater-Derived Contaminants

2006 ◽  
Vol 3 (6) ◽  
pp. 439 ◽  
Author(s):  
Martha J. M. Wells
Keyword(s):  
Drinking Water ◽  
Wastewater Treatment ◽  
Water Treatment ◽  
Surface Water ◽  
Water Distribution ◽  
Drinking Water Treatment ◽  
The United States ◽  
Water Soluble ◽  
Water And Wastewater Treatment ◽  
Ph Dependent

Environmental Context. Worldwide, surface water is a source of drinking water and is a recipient of wastewater effluents and pollutants. Many surface water bodies undergo a natural, cyclical, diurnal variation in pH between 7 and 9. Most drinking water and wastewater treatment in the United States is conducted between pH 7 and 8. The pH of water undergoing treatment processes directly impacts the ratio of nonionized to ionized chemical form(s) present, which in turn impacts the success rate of contaminant removal. Many organic wastewater-derived contaminants are very water soluble at pH 7–8 and are inadequately treated. Abstract. Wastewater-derived contaminants (WWDCs) occur in surface water due to inadequate wastewater treatment and subsequently challenge the capabilities of drinking water treatment. Fundamental chemical properties must be understood to reduce the occurrence of known WWDCs and to better anticipate future chemical contaminants of concern to water supplies. To date, examination of the fundamental properties of WWDCs in surface water appears to be completely lacking or inappropriately applied. In this research, the hydrophobicity–ionogenicity profiles of WWDCs reported to occur in surface water were investigated, concentrating primarily on pharmaceuticals and personal care products (PPCPs), steroids, and hormones. Because most water treatment is conducted between pH 7 and 8 and because DOW, the pH-dependent n-octanol–water distribution ratio embodies simultaneously the concepts of hydrophobicity and ionogenicity, DOW at pH 7–8 is presented as an appropriate physicochemical parameter for understanding and regulating water treatment. Although the pH-dependent chemical character of hydrophobicity is not new science, this concept is insufficiently appreciated by scientists, engineers, and practitioners currently engaged in chemical assessment. The extremely hydrophilic character of many WWDCs at pH 7–8, indicated by DOW (the combination of KOW and pKa) not by KOW of the neutral chemical, is proposed as an indicator of occurrence in surface water.

scholarly journals Insights into Solar Disinfection Enhancements for Drinking Water Treatment Applications

2021 ◽  
Vol 13 (19) ◽  
pp. 10570
Author(s):  
Abdassalam A. Azamzam ◽  
Mohd Rafatullah ◽  
Esam Bashir Yahya ◽  
Mardiana Idayu Ahmad ◽  
Japareng Lalung ◽  
...  
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Drinking Water Treatment ◽  
Water Disinfection ◽  
World Health ◽  
Solar Disinfection ◽  
Physical Chemical ◽  
Main Challenge ◽  
Pre Treatment ◽  
Health Organization

Poor access to drinking water, sanitation, and hygiene has always been a major concern and a main challenge facing humanity even in the current century. A third of the global population lacks access to microbiologically safe drinking water, especially in rural and poor areas that lack proper treatment facilities. Solar water disinfection (SODIS) is widely proven by the World Health Organization as an accepted method for inactivating waterborne pathogens. A significant number of studies have recently been conducted regarding its effectiveness and how to overcome its limitations, by using water pretreatment steps either by physical, chemical, and biological factors or the integration of photocatalysis in SODIS processes. This review covers the role of solar disinfection in water treatment applications, going through different water treatment approaches including physical, chemical, and biological, and discusses the inactivation mechanisms of water pathogens including bacteria, viruses, and even protozoa and fungi. The review also addresses the latest advances in different pre-treatment modifications to enhance the treatment performance of the SODIS process in addition to the main limitations and challenges.

Seasonal Variation in Drinking Water Disinfection By-products in Gharbia Governorate, Egypt

2021 ◽  
Vol 1 (2) ◽  
pp. 11-14
Author(s):  
Rafat Moustafa ◽  
Ali M. Hassan ◽  
Hamdi A. Hammad ◽  
Ali M. Abdullah
Keyword(s):  
Drinking Water ◽  
Continuous Monitoring ◽  
Drinking Water Treatment ◽  
International Standards ◽  
Water Disinfection ◽  
Dichloroacetic Acid ◽  
Mean Values ◽  
Drinking Water Disinfection ◽  
Congenital Disabilities ◽  
By Products

Chlorine is the most common disinfectant used in drinking water treatment because it is cheap and has an efficient germicidal ability. However, chlorine and organic matter reacting trihalomethanes (THMs) are suspected carcinogens. The major groups of disinfection by-products (DBPs) are THMs, haloacetic acids (HAAs), haloacetonitriles (HANs), and halogenated ketones (HKs). Exposure to these by-products increases the risk of cancers, abortion, low birth weight, and congenital disabilities. The wastewater contents of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), as the source of total organic carbon (TOC) compounds, are oxidized by chlorine to produce DBPs. This study aimed to monitor the seasonal levels of THMs in Egypt compared with international standards using capillary gas chromatography. Results revealed that THMs mean values vary between 9.26 to 35.86 μg/l, while dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) mean values vary between 3.82 to 17.74 μg/l and 4.41 to 13.25 μg/l, respectively. The maximum THM and TCAA values were observed during the summer, probably due to high temperatures. While the maximum DCAA values were observed during the autumn due to the high levels of raw water TOC. In conclusion, continuous monitoring of THM and its species is highly recommended, taking into consideration how climate can influence THMs formation.

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