Estudo em escala real da disposição de resíduo de decantador de ETA em lagoa de estabilização de esgoto

• Autor(a) principal: Angelim, Susane Campos Mota
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/5007
• topic: Gestão de resíduos; Resíduo de ETA; Iodo; Tratamento de esgoto; Lagoa de estabilização; Residuals management; Alum sludge; Water treatment plant residuals; Wastewater treatment; Wastewater stabilization pond; ENGENHARIAS::ENGENHARIA SANITARIA

In Brazil water treatment plants (WTP) residuals are usually discharged into waterways, with negative impacts on water quality, aquatic biota and sediments, which may also pose risks to human health. This paper presents a study on real scale disposal of aluminum sludge from the settling of a WTP in a primary facultative pond, both located in Piracanjuba-GO, wishing to contribute as an alternative for residuals management. The study aimed to evaluate the effects of WTP residuals (WTPR) in the performance of the wastewater stabilization pond (WSP), in terms of quality of the effluent and volume of bottom sludge accumulated. Worked up in two identical parallel ponds, one in which WTPR was applied (test pond) and another without application (control pond) to serve as comparison of results. The study was carried out in two stages, with dosage of 37 mg TS/L in Phase 1 and 44 mg TS/L in Phase 2, totaling 125 days of application and 191 days of monitoring. It was evaluated several effluent parameters such as BOD, solids, nitrogen, total phosphorus, Escherichia coli, metals, among others. Sludge volumes in the ponds were obtained from bathymetric survey using a sludge depth meter (sludge gun) and modeling by Surfer 8.0 software. The addition of the WTPR did not impair the performance of the test pond, with minimal reduction of BOD and nitrogen. It was not possible to identify any influence of WTPR for the removal of total phosphorus of the sewage, which was attributed to high pH and low dosage. There was no statistical difference (95% confidence level) between the means of 15 parameters evaluated in two phases, except for nitrogen ammonia. There was no difference between the increases of sludge volume accumulated in the bottom of the ponds, although total solids content was higher in the test pond. This behavior was associated with particle size characteristics of the material. The study indicates technical feasibility of WTP residuals disposal in the WSP studied, revealing an alternative for its management that can also be applied in other same type systems if evaluated the specific conditions in each case.