RESUMO
Existing disinfectants are oxidative agents which all present negative effects on subsequent treatment processes. None of them has decisive advantages over chlorine, although chlorine-dioxide and chloramines might at times be preferable. Optimum treatment practices will improve the removal of organic precursors before final disinfection which could then consist in a light chlorine addition. A philosophy of radical change in water treatment technology encompassing physical treatment without chemicals such as membrane filtration, solid disinfectants is presented.
Assuntos
Compostos Clorados , Cloro , Desinfecção/efeitos adversos , Esterilização/efeitos adversos , Poluição Química da Água/prevenção & controle , Animais , Cloraminas/efeitos adversos , Desinfetantes/efeitos adversos , Filtração , Camundongos , Óxidos , Ozônio , Peróxidos , Permanganato de Potássio , Fatores de Tempo , Poluentes Químicos da Água/efeitos adversos , Poluição da Água/prevenção & controleRESUMO
Ozone and chlorine dioxide present definite advantages and disadvantages over chlorination. Chlorination, particularly for the removal of ammonia and the maintenance of a disinfectant residual in the distribution system has decisive advantages and will be difficult to replace. Ozone and chlorine dioxide seem to produce fewer carcinogenic by-products but the risk for acute toxicity, especially from the chlorites which follow chlorine dioxide, is higher than with chlorine. Chlorine dioxide and more particularly ozone should be considered as useful complements to chlorination, but no strong oxidative treatment should be applied before most of the organic matter has been removed.