Drinking chemical oxidation

Physical disinfection of drinking water is mainly carried out through photodegradation by ultraviolet radiation (UV). Because many pharmaceuticals have chromophores that absorb UV wavelength, UV irradiation can lead to some transformation. Comparing to chemical oxidation, such as chlorination, UV disinfection has an advantage of minimizing the formation of DBPs [73]. However, at a... 

Discnss the source and problem of iron and manganese in drinking water. Introduce the application of chemical oxidation precipitation process for iron and manganese removal in a potable water treatment system. 

Chemical oxidation shows several potential benefits compared to other treatment options. The main advantage is the possible minerahzation of organic substances to carbon dioxide and water. The substance can be completely de-structed and is not only simply enriched or shifted into another phase [33]. Furthermore, there is also a disinfecting effect if ozone is used. Ozonation is the oxidative treatment process most widely spread in drinking water treatment—though it is mainly implemented for disinfection and the oxidation is only considered a beneficial side effect [28]. 

Because of their suitability for disinfection and oxidation (e.g., taste and odor control, micropollutant removal), chemical oxidants are commonly used in water treatment processes. In drinking water treatment systems, the oxidants coimnonly used are chlorine, chlorine dioxide, chloramines, and ozone. 

Gary Runyan (written discussion)—The paper addressed aging due to different times at different temperatures, basically an oxidative condition. There are also chemicals that will cause oxidative failures iaplastics that appear to be identical to those caused by heat alone. The application I am thinking about is plastic pipe with chlorinated drinking water. In hot water plumbing applications, the pipe is subjected to thermal oxidation from the heat and chemical oxidation from the chlorine in the water. In tests, the failures induced by thermal oxidation appear to be identical to failures induced by chemical oxidation. 

At present, chlorine dioxide is primarily used as a bleaching chemical in the pulp and paper industry. It is also used in large amounts by the textile industry, as well as for the aching of flour, fats, oils, and waxes. In treating drinking water, chlorine dioxide is used in this country for taste and odor control, decolorization, disinfection, provision of residual disinfectant in water distribution systems, and oxidation of iron, manganese, and organics. The principal use of chlorine dioxide in the United States is for the removal of taste and odor caused by phenolic compounds in raw water supplies. 

Potassium permanganate treatment methods are under development by the U.S. Department of Energy (DOE) and have been evaluated in field demonstrations. The technology is commercially available. CAIROX is a strong oxidant that has also been used commercially for many years in the chemical manufacturing, drinking water, and wastewater industries. 

Acetaldehyde is a natural product of combustion and photo-oxidation of hydrocarbons commonly found in the atmosphere. It is an important industrial chemical and may be released into the air or in wastewater during its production and use. It has been detected at low levels in drinking-water, surface water, rainwater, effluents, engine exhaust and ambient and indoor air samples. It is also photochemically produced in surface water. Acetaldehyde is an intermediate product in the metabolism of ethanol and sugars and therefore occurs in trace quantities in human blood. It is present in small amounts in all alcoholic beverages, such as beer, wine and spirits and in plant juices and essential oils, roasted coffee and tobacco smoke (lira et al., 1985 Hagemeyer, 1991 United States National Library of Medicine, 1998). 

The detection of new kinds of microorganisms, such as the cysts and oocysts of parasites (Giardia, Cryptosporidium), the identification of more and more chemical pollutants in waters and increasing quality levels required for drinking and waste waters has induced new interest in ozonation and ozone-based advanced oxidation processes. However, care has to be taken in the application of ozonation, since recent research has indicated that presumably hazardous by-products can be formed, e. g. bromate in the ozonation of waters containing bromide. 

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