Post-treatment of UASB reactors effluent using constructed wetlands.

Abstract

UASB reactors are widely used for the treatment of sanitary sewers due to their low operation costs and low sludge generation. However, this technology, merely, cannot reach the adequate levels of efficiency to effluent discharge in water bodies. Currently, the ecotechnological process for treatment of sanitary sewage called “constructed wetlands” is a consolidated technology that allows organic matter removal rates above 80%, has simple operation and low cost. This research consisted in design, constructing and monitoring a vertical flow constructed wetland pilot system with continuous feed and receiving treated sanitary sewers from UASB reactors. The results indicate high rates of organic matter removal (84.9%) and average nitrates addition of 3.54 mgNO3 -N.L-1 in the effluent, besides removal of Total Phosphorous (P-PO4) and Total Nitrogen of 37.2% e 27.3% respectively, but low efficiency related to bacteriological parameters (≈1 log unit for E. coli).

Keywords

• vertical flow constructed wetlands. constructed wetlands. typha domingensis pers. uasb. real-scale constructed wetlands. post-treatment.