Tratamento de água de chuva através de filtração lenta e desinfecção UV

• Autor(a) principal: Bastos, Fernanda Pereira
• Data de Publicação: 2007
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/1933
• topic: Engenharia Sanitária; Águas pluviais; Filtros e filtração; Água potável; Desinfecção ultravioleta; 628

In the face of water scarcity problems in the present time, the use of alternative supply sources is cited as solution for the water conservation. Among these sources, the main is the rainwater catchment system, characterized by a simple and cheap solution to preserve drinking waters. In this context, this research promoted a characterization of the rainwater, making it possible a system of treatment of this water making viable the smallest operational demand possible, and thus, contributes to improve the quality of life of populations that do not have access to drinking waters with low impact possible to the environment. The present work establish the guidelines for the conception and elaboration of a project of water supply, where the treatment will be through Slow Filters and ultraviolet disinfection – keeping in mind that the chlorination, conventional method, demand a operational high cost, and also is rejected by some communities, because of the taste of the chlorinated water. The roofs of the building located in the “Parque Experimental do Núcleo Água” were utilized for the rainwater capitation, were constructed with metallic tile and, approximately, 180m ² of total projection area. Annex to the building was constructed a system of storage and treatment of the rainwater, is formed by two vertical slow filters and ultraviolet light bulbs. The characterization occurred through by 12 weekly physical-chemical analyses: temperature, pH, turbidity, true color, suspended solids, dissolved solids and total solids, acidity, alkalinity, hardness, chloride -the first three were carried out every day; and microbiological analyses, like: thermo tolerant and total coliforms and Escherichia coli. The rainwater was analyzed without treatment after passage through the slow filters with different filtration rates (4, 6 e 8 m3/m2 day), and after passage through ultraviolet disinfection with average of the 0,57 mW/cm2 . The rainwater analyzed can be classified according to CONAMA 357/05 is class 1 and according to NBR 12.216/92 is type B, being necessary in both classifications a treatment for the consumption. The quality of rainwater, after slow filtration, regarding Brazilian Ministry of Health Directive # 518/04, was, in general satisfactory, but is necessary the disinfection to be considered drinking water. The rate of ultraviolet radiation applied showed good efficacy for removal of microbiological studied in this research, being suitable for drinking.