Análise de desempenho e confiabilidade de reatores UASB em estações de tratamento de esgotos sanitários descentralizadas

Abstract

The present work aimed to perform a performance and reliability analysis of UASB reactors in 18 full-scale decentralized sewage treatment plants. Reliability was assessed using the methodology developed by Niku et al. (1979) for the parameters COD and SST. The verification of the form of the frequency distribution of these parameters consisted of tests of adherence to the Normal, Lognormal, Gamma and Exponential distributions, through the Chisquare and Kolmogorov-Smirnov tests. It was found that the COD and TSS effluent concentration data of UASB reactors followed a lognormal distribution. In general, the performance of the reactors in meeting the discharge standards for the COD and SST parameters was not satisfactory. In an integrated analysis of the reliability coefficients, project concentrations and expected compliance percentages, it was found the low reliability of most reactors in relation to the COD and SST constituents, being indicative of rganic and hydraulic overload, respectively.