Ozone water disinfection with

Preservatives, pharmaceutical preparations, 623 PRESS technique, NIR spectrophotometry, 624 Primary amines, dioxirane oxidation, 1151 Primary ozonides (POZ), 716, 717 dialkyl peroxide formation, 706 IR spectroscopy, 718, 719-20 microwave spectroscopy, 721 molecular model, 750 NMR spectroscopy, 709, 723-4 octaUn ozonation, 165 ozone water disinfection, 606 7r-complexes with ozone, 732... 

Can ozone be used as the only means of water disinfection in a treatment facility If not, why not, and what other technologies do you think would work in combination with ozone treatment ... 

Kinman, R. N. Water and wastewater disinfection with ozone A critical review. CRC Crit. Rev. Environ. Control 5 141-152, 1975. 

Zoeteman BCJ, Hmbec J, de Greef E, et al. 1982. Mutagenic activity associated with by-products of drinking water disinfection by chlorine, chlorine dioxide, ozone and UV-irradiation. Environ Health Perspect 46 197-205. 

Several operations may be employed to treat water prior to use. Aeration is used to drive off odorous gases, such as H2S, and to oxidize soluble Fe2+ and Mn2+ ions to insoluble forms. Lime is added to remove dissolved calcium (water hardness). A12(S04)3 forms a sticky precipitate of Al(OH)3, which causes very tine particles to settle. Various filtration and settling processes are employed to treat water. Chlorine, Cl2, is added to kill bacteria. Formation of undesirable byproducts of water chlorination may be avoided by disinfection with chlorine dioxide, C102, or ozone, 03. 

Since the abandonment of complementary hypochlorite treatment, the ozonized water has never shown the presence of E. coli. Thus the safety of this method of disinfection seems excellent on the basis of classical criteria. In 1952, with hypochlorite, Clostridium perfringens was reduced from an average of 40 units to 31 units per liter. In 1956, with ozone, an average of 50 units per liter was reduced to 22. 

A comparison of conventional means of mixing ozone with water for disinfection with two recently developed methods shows that the newer methods permit more effective utilization of ozone. Operating experiences with pilot plants utilizing these systems are described. With the new methods ozone dosage requirements can be reduced by as much as one half, while maintaining full bactericidal efficiency. 

The results of disinfection with the Torricelli system were surprising because they easily exceeded the most optimistic expectations. A speedy disinfection was possible with a small ozone dosage. The ozone dissolved in the water at a high rate because of the recovery system adopted to avoid ozone losses. 

Ozonization for water disinfection is returning instead of chlorination however, it is not devoid of potential dangers when micropollutants react with ozone. Thus, an aqueous solution of 3-phenylenediamine (lk) led to formation of the strongly mutagenic 2-amino-5-[(3-aminophenyl)amino] -4- (3-ami nophenyl)imino] -2,5-cyclohexadien-1 -one (66)89. 

Drinking water has been disinfected with chlorine for approximately 100 years to protect against waterborne infectious diseases. In addition to chlorination, other methods of drinking water disinfection include the use of chlorine dioxide (either alone or in combination with chlorine), the addition of ammonia to chlorine to form chloramines, ozone treatment, oxidation with potassium permanganate, and ultraviolet radiation. Chlorination, however, is by far the most widely used method. Treatment with chlorine has virtually eliminated cholera, typhoid, dysentery, hepatitis A, and other waterborne diseases)54 ... 

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