Análise da variação da taxa de aplicação superficial em um sistema francês de wetland construído

Abstract

Given the possibilities of treating different types of effluents by vertical flow constructed wetland systems (WCFV), this work sought to evaluate the influence of surface application rate on the efficiency of removing organic matter and nutrients, constituents of the sewage of a university restaurant. Seeking to evaluate the efficiencies of a WCFV system - French Model (WCFVF), the present work was carried out in a pilot scale system in an intermittent manner, operating with two stages in parallel, varying the application rate in 2, 6 and 8 pulses per day, lasting 1 minute each and flow rate of 0.025 m³ per minute. In order to favor denitrification nitrification processes, the system worked with a saturation level of the filter mass at 0.25m. The parameters analyzed in this work were pH and Alkalinity, Nitrogenated Series, Phosphate and chemical oxygen demand (COD). A reduction in the parameters was observed in the system, reaching 99% removal of organic matter (COD). It was observed, already in the first stage of the system, a reduction in the applied nitrogen load of up to 62%, followed by a reduction of up to 94% in the second stage. It was also observed a reduction of about 50% in the first stage and up to 91% in the second stage of the system for the total phosphate parameter, considering the conditions of the superficial application rate. Finally, he verified that, under the operational conditions adopted, the increase in the rate of surface application did not influence the overall efficiency of the system in the removal of organic matter and nutrients.