ANAEROBIC DIGESTION AND THE DENITRIFICATION IN UASB REACTOR (doi: 10.4090/juee.2008.v2n2.063067)

Abstract

The environmental conditions in Brazil have been contributing to the development of anaerobic systems in the treatment of wastewaters, especially UASB reactors – Up flow Anaerobic Sludge Blanket. The classic biological process, for removal of nutrients, use three reactors - Bardenpho System, therefore, this work intends an alternative system, where the anaerobic digestion and the denitrification happen in the same reactor, in this system, is reduced for two, the number of reactors. The experimental system was constituted by two units: first was a nitrification reactor with 35L volume and 15 days of sludge age. This system was feed with raw sanitary waste. Second unit was an Up flow Anaerobic Sludge Blanket (UASB), with 7.8 L and 6 hours of hydraulic detention time, feed with ¾ of effluent nitrification reactor and ¼ of raw sanitary waste. This work had as objective evaluates the performance of the UASB reactor, in terms of removal efficiency, of bath COD and nitrogen. It was verified that the anaerobic digestion process was not affected, the removal efficiency of organic material expressed in COD, was 71%, removal already expected for a reactor of this type. It was also observed that the denitrification process happened; the removal nitrate efficiency was 90%. Therefore, the denitrification process in reactor UASB is viable