الفهرس 
Ozonation ProcessOnly 14 pages are availabe for public view
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Abstract
Public and environmental health requires safe drinking water which means that potable water must be completely free of disease-causing microorganisms. To accomplish this, disinfection is applied as a final treatment process in water treatment plant. The number of different types of pathogens that can be present in water as a result of contamination with human or animal feces is very large and it is not possible to test water samples for each specific pathogen. Therefore, scientists and public health officials typically choose to monitor non pathogenic bacteria that are usually associated with pathogens transmitted by fecal contamination; but are more easily sampled and measured. These associated bacteria are called indicator organisms.
Disinfection is a process whose objective is the destruction or inactivation of pathogenic organisms responsible for water borne disease. Disinfection can only be completely checked by bacteriological tests. The effectiveness of disinfection is judged by analyzing for an indicator organism, such as faecal coliforms. This organism is considered harmless, but its presence indicates that pathogens may also have survived.
Ozone is one of the strongest disinfectants technically applied. The ozone molecule (O3) consists of three oxygen atoms and is considerably unstable. So ozone can not be stored or transport alike other gases, since when filled into containers it continuously decays until only oxygen is left. Therefore, it can only be produced at the place and the time of consumption from oxygen or air. The production consists of applying energy to molecular oxygen (O2), as an electrical discharge, through which by splitting and recombination three oxygen molecules can be transformed into two ozone molecules. It should be generated at the point of application for use in water treatment.
Ozone is becoming a popular disinfectant due to its effectiveness for killing harmful microorganisms and also because it does not produce significant concentrations of trihalomethanes (THMs) or other chlorinated disinfection by-products (DBPs). The effectiveness of ozone as a disinfectant can be increased by creating a higher surface-area-to-volume ratio for the contact of ozone with the water through the generation of which arises from smaller bubbles.