Drinking water filters

Ozone has many industrial applications. It is a sterilizing and deodorizing agent. It is used for disinfection of filtered drinking water and to purify waste-waters. It also is used in water treatment plants for removal of metal impurities by oxidizing them into insoluble compounds. This removes undesired taste, odor, and color from the water. Ozone also is used for odor control. 

BC Phoenicians use charcoal to store and preserve drinking water Hindus use charcoal to filter drinking water. 

Craik SA, Finch GR, Bolton JR, Belosevic M (2000) Inactivation of Giardia Muris Cysts Using Medium-Pressure Ultraviolet Radiation in Filtered Drinking Water, Wat. Res. 34, No. 18 4325-4332. 

Castro et al. [57] studied the influence of various ion-pair agents on the response of diquat and paraquat. The ion-pair LC separation is based on a 0.5-40% acetonitrile gradient in 15 mmol/1 aqueous HFBA. The compounds were analysed in tap water after a Sep-Pak sample pretreatment. The detection limits were 0.9 and 4.7 pg/1 in ESI and 0.1 and 1.8 pg/1 in APCI for diquat and paraquat, respectively. In a subsequent study [58], on-line SPE is performed on EN h-8 disks, after addition of 15 mmol/1 HFBA to the filtered drinking water sample. Detection limits were 50 and 60 ng/1 for diquat and paraquat, respectively. Further improvement of the detection limits to 30 ng/1 for both compounds was achieved by the use of on-line SPE-LC-MS-MS. The intra-day and inter-day precision for diquat were 9.4% and 12.8%, respectively [60]. In another study from the same group [95], an oa-TOF-MS, operated in full-spectram acquisition mode, and a triple-quadrapole instrament, operated in SRM mode, were compared. The detection limits with the triple-quadmpole instmment were at least tenfold better than those obtained with the oa-TOF instmment, i.e., 60 and 3 ng/1 in tap water for paraquat and diquat, respectively. 

S. A. Craik, G. R. Finch, J. R. Bolton, andM. Belosevic, Inactivation of Giardia muris cysts using medium-pressure ultraviolet radiation in filtered drinking water. Water Research 34, 4325-4332 (2000). 

Schwartz, Th., S.Eloffmann, U. Obst, Formation and Bacterial Composition of Young, Natural Biofilms Obtained from Public Bank-Filtered Drinking Water System, Wat.Res., 2000, Vol. 32, Ns 5, pp. 1495-1502. 

The limitations of ELISA methods include the specificity of antibodies, the concentrations of primary antibody and antigen, and the type of reaction solution. Nonspecific binding of either of the antibodies to related antigens, unrelated proteins of other bacteria, or even the microtiter plate may lead to false positive reactions.49,52 57 Use of a monoclonal antibody may decrease crossreactivity with other antigens. For detection of low numbers of bacteria, as in drinking water, the sample may be filtered to concentrate the cells or cultured in a selective broth until it reaches the minimum detection limit for ELISA.49,58 Commercial test kits using dipsticks, immunoblots, and sandwich ELISA methods have been developed for the identification of pathogenic bacteria.58,59... 

Berndt et al. [740] have shown that traces of bismuth, cadmium, copper, cobalt, indium, nickel, lead, thallium, and zinc could be separated from samples of seawater, mineral water, and drinking water by complexation with the ammonium salt of pyrrolidine- 1-dithiocarboxylic acid, followed by filtration through a filter covered with a layer of active carbon. Sample volumes could range from 100 ml to 10 litres. The elements were dissolved in nitric acid and then determined by atomic absorption or inductively coupled plasma optical emission spectrometry. 

The created technology of producing cationic and anionic exchange fibroid sorbents on the base of polyacrylonitrilic fibers is described in the paper. Chemical characteristics of the sorbent and filters were investigated. The static exchange capacity is 3-4 meq/g for cationic sorbents and 1-2 meq/g for anionic sorbents. The removal coefficient of listed radionuclides from drinking water by the filter is 102 - 103. 

After the Chernobyl accident the Academy of Sciences and KGB of Ukraine tested the household filters with fibroid sorbents and ten thousands filters were produced in the Institute of Nuclear Physics of Uzbekistan and given to Ukraine through "Isotope" Corp. (USSR). The experience of using the filters for purification of drinking water from radionuclides in Chernobyl region is described in the paper. 

These experiments have confirmed that the filters have removal coefficients of radionuclides for water from Chernobyl of 102 - 103 Thus, the water meets the requirements for drinking water after passing the filter. However, the high efficiency of the filter causes problems due to accumulation of radioactivity by filters, increasing the difficulty of controlling radioactivity at homes and the necessity of removal of... 

Water and Feed. Like all animals, pigs should be permitted free access to potable water, preferably from a municipal water supply intended for human consumption. Drinking water intended for pigs does not have to be filtered or deionized. Various diets have been described. Because of their size (i.e., high maintenance charges and test articles demand), pigs have seldom been used for chronic studies where the possibility of waterborne envinronmental contaminants could influence a study. 

Early work by Rivera et al. [27] indicated that GAC filters installed at the waterworks Llobregat were capable of retaining different polar pollutants including LAS, NPEO and PEG, but most of them reached (to an unknown portion as the applied fast atom bombardment (FAB)-MS method only yielded qualitative results) the drinking water. Hence, further examinations covering at least one GAC cycle should be performed to obtain more information on the efficacy of GAC filtration... 

Chemical-based products cover a broad spectrum of materials and forms, ranging from molecules to appliances. Table 16.1-1 shows the various product functional forms, along with examples in major application areas. Examples highlighted in italic are those discussed in this book. Most small molecules such as BTX (benzene-toluene-xyxlene) are sold to chemical and allied products industries while a limited number such as refrigerants and solvents are for sale in the consumer market. In contrast, multicomponent liquid mixtures such as liquid shampoo, semi-solids such as cream and paste, and structured solids such as controlled release herbicide are often sold directly to the consumers. Business-to-consumer sale is even more prevalent for ready-to-use devices and appliances such as diagnostic kits, drinking water filters and air cleaners. 

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