Influência da adição de micro-organismos eficientes no tratamento de esgoto sanitário utilizando reator aeróbio em bateladas sequenciais

Abstract

Throughout the years, has been standing out the importance of microorganisms in wastewater treatment. One of the alternatives being studied for the treatment is the use of Effective Micro-organisms. Therefore, this study aimed to compare the performance of two reactors in Sequential Batch Aerobic containing biomass suspended and adhered in wastewater treatment, one with addition of EMs (RBSAe1) and another without adding EMs (RBSAe2). For perform the experiment two reactors were built with the same dimensions, where the configuration was intended to increase the active biomass in the reactors, and for this purpose was performed the retention of sludge and biomass attached on the support medium at the end of each cycle. The reactors have operated on with the following steps of: filling (5 min), reaction (411 min), sedimentation (60 min), discard (2 min) and rest (2min). Physicochemical analyzes (COD, solids, pH, DO and temperature) and microbiological (quantification of Heterotrophic Bacteria, EMs - Yeasts, Actinomycetes and Bacteria Fermenting Lactose and Escherichia coli) were performed to evaluate the performance of the reactors. Both reactors have stabilized at removing organic material from the 25th cycle and the average efficiency of total COD removal was of 84% in RBSAe1 and of 83% in RBSAe2, and for the COD Filtered removal efficiency in both reactors was 80%. Regarding the number of solids removal TS, TVS, TSS and VSS, it was respectively of 54%, 87%, 70% and 86% in RBSAe1 and 56% 86% 73% and 84% in RBSAe2. The average removal efficiency E. coli in the second reactor was of 98%. Comparing the two reactors there was no difference between the average of removing parameters. The Heterotrophic Bacteria, Yeasts, Actinomycetes and Bacteria Fermenting Lactose were present in suspended and adhered biomass, in the cycle 76 was quantified in the sludge respectively 3,5x106, 4x105, 6x106 4x103 CFU/mL in RBSAe1 and 2,5x107, 6,3x105, 1,5x107, 1,7x104 CFU/mL in RBSAe2, and in the foam the value was 1x1010, 2,4x107, 3,1x108, 1,7x105 CFU/foam in RBSAe1 and 2,5x1010, 9x106, 1,1x109, e 1,4x105 in the RBSAe2, which may instigate that contributed to the performance of the system. The results showed that the system sequential batch reactor aerobic with suspended and adhered biomass showed good performance. The influent wastewater used had concentrations of EMs, causing the proportion used 1/1000 (EMs solution/Sewage Influent) was not enough to provide a significant difference in performance comparing RBSAe1 with RBSAe2.