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Chlorination disinfection of water

In addition, brominated derivatives of alkylphenols (BrNPnEO and BrNPnEC) can be formed during chlorine disinfection of water if... [Pg.429]

Anderson AC, Reimers RS, DeKemion P. 1982. A brief review of the current status of alternatives to chlorine disinfection of water. Am J Public Health 72(11) 1290-1293. [Pg.128]

Chlorine disinfection of waters Cl is a powerful oxidizing agent which can have a dual biocide and coagulation action on OM by breaking it down. It acts in the form of hypochlorous add produced between pH 5 and 10 ... [Pg.40]

Emerson, D.W. Polymer-bound Active Chlorine Disinfection of Water in a Flow System. Polymer Supported Reagents. 5. Ind. Eng. Chem. Res. 1990, 29,448. [Pg.41]

The losses of chlorinated benzenes and nitrobenzene in the chemical industry are probably low - also because of the low vapour pressure - and will total less than 20,000 t. Losses from its use as a solvent could be higher, perhaps in the order of 50,000-100,000 t worldwide. The quantities of chlorinated aromatics formed during the chlorine disinfection of waters are difficult to assess, but are probably low. [Pg.124]

Pure Ti02 was recently reported to be active in the disinfection of water contaminated by spores of the type Fusarium solani [142], Bacillus anthracis [143], or Cryptosporidium parvum oocysts [144], or when supported as nanocomposites on zeolite H(i for E. coli deactivation [145], and it found applications in water treatment as a replacement for chlorine. Ag-Ti02 immobilized systems were used for inactivation of bacteria, coupling the visible light response of the system and the strong bactericidal effect of Ag [146]. Silver was deposited on hydroxyapatite to form nanocomposites with a high capacity for bacterial adsorption and inactivation [147], or used for airborne bacterial remediation in indoor air [148],... [Pg.107]

In more recent in-depth investigations on this issue [22], a series of chlorinated and brominated by-products of alkylphenolic surfactants and their degradation intermediates formed during chlorine disinfection of raw water were identified using mass spectrometry (Table 6.6.2). [Pg.798]

The fate of dissolved amines during disinfection of water by chlorination was determined by membrane injection MS. Aliphatic amines undergo TV-chlorination to exhaustion of the N-H atoms by one of the tentatively proposed paths shown in reaction 28. Aromatic amines undergo mainly ring substitution however, the possible intervention of N-C1 intermediates is not excluded. At pH 10.6 aniline chlorination is much slower than that of n-butylamine383. [Pg.1107]

One practical use of Fenton and photo-Fenton processes is the removal of natural organic matter (NOM) from organic rich waters before the chlorine disinfection of drinking water. It was observed that, under optimal conditions, both processes achieved more than 90% TOC removal, leading to the potential formation of trihalomethanes at concentrations below 10 ig IT1, well under UK and US standards [78]. [Pg.349]

The main uses of chlorine are the following (l)the production of chloro-organic compounds, snch as vinyl chloride and ethylene dichloride for the plastics indnstry, as solvents, refrigerants, insecticides, and dyes (abont 70%) (2) as a bleaching agent of paper, pnlp, and textiles, and the disinfection of water snpplies (abont 20%) and (3) for the production of a large variety of inorganic chemicals, particularly covalent compounds. [Pg.740]

Chlorine and chlorine-releasing compounds have been used in the disinfection of water supplies for more than a century. The di.scovery that hypochlorous acid (HCIO) is the active germicidal species that is formed when chlorine is dissolved in water led to the development and use of the first inorganic hypochlorite salts such as NaOCI and Ca(OCI) . Later, organic Af-chloro compounds were developed as disinfectants. These compounds release hypochlorous acid when dissidvcd in water, especially in the presence of acid. Two equally plausible mechanisms have been proposed for the germicidal action of hypochlorous acid the chlorination of amide nitrn-... [Pg.223]

In the chlorine disinfection, reducing agents like sulfur dioxide must be used to eliminate the discharged toxic chlorine. Besides, special considerations must be applied to control natural organic matter (NOM) in water source or to reduce the potential by-product precursors after the disinfection unit. These concerns however become less obvious when UV radiation is used for disinfection of water. [Pg.343]

Dechlorination is an evolving practice in the water industry. Currently, there is no industry guidance or American Water Works Association (AWWA) standard for disposal of chlorinated water (5-7). The AWWA standard for disinfection of water mains (C651-92) provides some information on disposal of chlorinated waters. This information, presented as an appendix, is not a part of the standard. Regulations and permit programs for disposal of chlorinated waters vary widely among the states and provinces. [Pg.443]

In 1974 it was discovered that the use of chlorine in the disinfection of water leads to the formation of a group of compounds referred to as the trihalo-methanes. This group of compounds includes chloroform, bromodichloromethane, dibromochlo-romethane, and bromoform. The relative concentrations of the members of this class depend on the concentration of bromide in the water being disinfected. In recent studies, it has become clear that the trihalomethanes are only one class of by-products and that there are small concentrations of a wide variety of chemicals produced with chlorination. However, it should be recognized that all chemical disinfectants are reactive compounds and, as a consequence, all will produce unintended by-products as a result of their use. [Pg.2084]

It was discovered in the 1970s that chlorination of raw water high in organic content and/or infused with seawater results not only in the disinfection of water, but also in the formation of disinfection by-products (DBPs). These include trihalomethanes (THMs), haloacetic acids (HAAs), and haloacetonitriles (HANs) J55-56 These chemicals are individually toxic at high concentrations and can cause cancer, liver disease, kidney disease, birth defects, and reproductive failuresJ57 59 ... [Pg.95]

Calcium or sodium hypochlorite (e.g., household bleach) is also effective for disinfection of water supplies, and is a convenient choice for smaller volumes when required, such as for a single household, a hamlet, or for small campsites [7, 8]. Hypochlorite solutions are somewhat more expensive to buy than compressed chlorine gas, but the equipment required for metering it into the supply is simpler. With hypochlorite salts, similar equilibria operate to rapidly establish a concentration of hypochlorous acid, which corresponds to the amount of hypochlorite salt added (Eq. 5.7, Table 5.2). [Pg.143]

Waterborne pathogens were responsible for tens of thousands of deaths during the first 150 years of U.S. history, with more than 50,000 deaths from typhoid fever as late as 1900-1904 Worldwide, cholera outbreaks were eventually traced to contaminated water. Disinfection of water in the early 1900s with chlorine compounds and then with elemental chlorine nearly eliminated waterborne diseases such as cholera, typhoid, dysentery, and hepatitis in U.S. cities. Together with improvements in sewage treatment, this ranks among the most important contributions made by science and engineering to the improvement of human health.0... [Pg.38]

Cholera organism can be a potential bio-weapon. Contamination of public water systems can spread the disease rapidly. However, simple processes such as chlorination or disinfection of water or just boiling the water should serve as a preventive measure against cholera. There is no record of use of cholera organism in the war, although this agent was considered in the past as a biological weapon. Cholera bacteria can be a potential bio-weapon in terrorism. [Pg.93]

The disinfection of water by direct electrolysis is in effect a modification of chlorination and in principle offers the same properties and follows the same mechanisms. Disinfection is effective at residual chloride ion con-... [Pg.395]

Although the industrial production of chlorine and sodium and calcium hypochlorites already started in 1785, it was not before the first half of the 19th century that the deodorizing and disinfecting properties of chlorine and hypochlorites were detected and led to the use of chloride of lime in hospital wards. Before that time chlorine and hypochlorites were used in textile bleaching. In 1881 Robert Koch demonstrated scientifically the microbicidal effect of hypochlorites by exposing pure cultures of bacteria to chlorine compounds. Thirteen years later Traube proved that hypochlorites can be used successfully for the purification and disinfection of water. [Pg.434]

Disinfection of Water, Electrochemical, Fig. 5 Quasi-linear behavira- of chlorine (FAC) prxxluction versus chloride concentration (/ ) and FAC current efficiencies versus chloride concentration at different current densities (right)... [Pg.340]


See other pages where Chlorination disinfection of water is mentioned: [Pg.35]    [Pg.3238]    [Pg.35]    [Pg.3238]    [Pg.456]    [Pg.120]    [Pg.136]    [Pg.606]    [Pg.282]    [Pg.606]    [Pg.346]    [Pg.234]    [Pg.143]    [Pg.461]    [Pg.86]    [Pg.280]    [Pg.368]    [Pg.644]    [Pg.76]    [Pg.120]    [Pg.265]    [Pg.33]    [Pg.309]    [Pg.5008]    [Pg.387]   
See also in sourсe #XX -- [ Pg.279 ]

See also in sourсe #XX -- [ Pg.279 ]




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