Avaliação da formação de trihalometanos em um sistema de abastecimento de água para consumo humano

• Ano de defesa: 2011
• Autor(a) principal: Nogueira, Adriano de Souza
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Saneamento; Engenharia hidráulica; Abastecimento de água
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/3679

This study aims to evaluate the formation of halogenated organic compounds, specifically trihalomethanes in a Water Supply System that uses direct descendant filtration technology, pre-oxidation with chlorine dioxide, coagulation with polyaluminium chloride aided by a cationic polymer. This paper considered the main parameters that influence the formation of trihalomethanes in aqueous medium, according to results of research in the specialized technical literature, namely: pH, contact time, temperature, concentration of bromide and residual chlorine. Additionally, it was evaluated a few items of operational processes that exert an influence on the potential for formation of by-products, such as reaction efficiency of the production process of dioxide by generators installed at the treatment station, plans to control the spread of the THM throughout the water supply network, the interference of the weather (rainy season and dry season), influence of the limiting agent in the reaction process to produce chlorine dioxide, the dosing points of the oxidants used and the definition of control points in the water supply network. These parameters are highlighted as a priority: the high THM concentrations observed in the water distributed, where only 36% of the samples had values below the limit determined by the existing laws of Ministry of Health. Among the trihalomethanes identified, Chloroform was most frequently detected, followed by bromodichloromethane, dibromochloromethane and bromoform, that indicates chlorine as the agent that more enables the formation of byproducts in the system. The current scenario of the treated water quality all along the supply system investigated, requires strategic actions to mitigate the factors that increase the formation of THM avoiding to compromise public health in the region studied.