Tratamento dos resíduos de fossas e tanques sépticos em um sistema de alagado construído

• Autor(a) principal: Siqueira, Elisa Rodrigues
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/001300000b299
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tde/2936
• topic: Zona de Raízes; tanque séptico; capim Vetiver; Root Zone System; septic tank; ENGENHARIA SANITARIA::RECURSOS HIDRICOS

Due to the lack of public sewer service in the country, Individual and Household Sewage Disposal Treatment Systems (SITDE) are still widely used in Brazil. The SITDE require cleaning maintenance and at the time of execution of this cleaning occurs the generation of the called Pit and Septic Tanks Waste (RFTS). This material has high load of pollutants and presence of pathogenic organisms and must be properly designed to ensure the quality of the environment and safeguard public health. In this context, low cost and potential for deployment in small settlements technologies emerge as an alternative of treatment. This study aimed to evaluate the efficiency of the Constructed Wetlands System (SAC) with the Vetiver plant species (Chrysopogon zizanioides) in the treatment of the liquid fraction of the RFTS. An experimental system was built with the deployment of two identical tanks. One tank received the vegetation and the other operated as a control treatment. The tanks were filled with a substrate consisting of gravel # 0, gravel # 1 and medium sand. The constructed wetland system (SAC) acted under a descending vertical subsurface flow and RFTS was applied on the system under batch, remaining in the tanks for a period of six (6) days. The RFTS influent to the treatment system was characterized according to the parameters of pH, total oil and grease, ammonia nitrogen, settleable solids, total coliforms, Escherichia coli, surface, solid fixed solids, volatile solids, Biochemical Oxygen Demand (BOD) and total phosphorus. The RFTS treated by SAC was analyzed according to the same parameters and the results were compared with the stipulations for disposition in water bodies of class 2, according to Resolution 430/2011 of Conama and Goiás State Decree 1.745/1979. The attributes removal efficiency was calculated considering the phenomenon of evapotranspiration, which showed an average rate of 38.11% in the SAC. The tributary RFTS system showed a great variability in the concentrations of the attributes. The results were subjected to F test (5% probability). Statistically, the only differed treatments between the tank vegetated and the tank control was removal of BOD which was more effective WS with the average removal of 86.80 %, while the tank control showed an average increase of 65.94 %. The average concentrations output WS met the requirements under federal and state law , except for E. coli showed an average outlet concentration can change the class of the receptor. Statistically, the treatments (vegetated tank and control tank) differed only for the BOD removal, which was more effective for the SAC, with the average removal of 86.80%, while the tank control showed an average increase of 65.94%. The average concentrations of SAC output attended the provided by the federal and state laws or release in Class 2 water.