Tratamento de esgoto sanitário sintético por sistema combinado constituído pelo reator UASB e biofiltro aerado submerso

Abstract

The sewage treatment is directly related to environmental aspects, because once thrown into water bodies without adequate pre-treatment, this can cause major environmental impacts. Thus the implementation of treatment systems that meet environmental legislation about the parameters of release is required. The type of treatment is commonly used biological UASB reactor being widely used in the ETEs. The effluent obtained does not reach the limits allowed by statutory requirements, particularly with respect to nitrogen. Thus the implementation of a post-treatment is required. The BFAS has been used for this purpose. This work aimed at the construction of a combined UASB/BFAS, uniting the positive aspects of anaerobic treatment with aerobic to build a compact and meets the parameters established by legal requirements ETE. Furthermore, this study evaluated the effectiveness of a support material for the unconventional BFAS and the specific methanogenic activity of the sludge used as inoculum in UASB reactor. The monitoring of the experimental system was divided into three stages. 1st step: operation of the UASB reactor. 2nd step: start of operation of BFAS, introduction of material support and aeration system (beginning of operation of the combined reactor). 3rd step: start recirculation of aerobic sewage BFAS anaerobic compartment and functioning of the decanter. The third step in monitoring achieved the best results for the final drain, with an efficiency of 81.07% for the removal of ST and 89.08% removal of TSS with respect to organic matter, that removed 93% of the DQO and 92% of DQO filtered. The processes of nitrification and denitrification, with an efficiency of 66% total nitrogen removal were observed. The material proved to be an alternative as a means to support BFAS in wastewater treatment. With respect to AME, the anaerobic sludge showed high productivity, 1.6 gDQOCH4/gSSV.dia. Through this work, it was found that the combined reactor preceded by a secondary clarifier was effective in removal of both solid as well as in the removal of organic and nitrogenous matter. Where high productivity of anaerobic sludge contributed somewhat to system performance.