Remoção de Microcystis aeruginosa e microcistina-LR de águas superficiais com uso de filtro doméstico seguido de processo oxidativo avançado (UV/H2O2)

Abstract

The presence of productive cyanobacteria and cyanotoxins has a negative effect on water in particular in food for the absorption of human and human energy. In general, cyanotoxins are not removed by water energy waves, alarming fact, as people are warmer, water currents are not treated. The present study aimed to evaluate the efficiency of the removal of Microcystis aeruginosa and Microcystin-LR (MC-LR) cells from a system consisting of two filtration systems of two different types of filter elements: F1- with candles composed of successive layers of Kaolin, phyllite, composite PVC, thermoplastic resins, microporous wall collection with 1.0 μm pores and F2- with candles composed of successions of Kaolin, Filito, Colloidal Silver, Activated Carbon, Stainless Steel, PVC, Hot Melt, microporous wall with 0.5 μm pores, followed by photocatalytic reactor (UV / H2O2). The research was carried out in three stages: I: raw water (AB) collection in the Saulo Maia reservoir; Calculation of M. aeruginosa II cells: study water preparation (AE) which consisted of the supplementation of lysed cells of M. aeruginosa in AB. In a following were then the AE filtrations by the F1 system and F2; III: application of advanced oxidative process (POA - UV / H2O2) to the effluents of F1 (AEF1) and F2 (AEF2) using a photocatalytic reactor. Six assays were carried out for each domestic filter effluent with different dosages of H2O2 (5, 25, 50, 100, 500, 1000 Mm) and AEF1 and AEF2 times of 1, 2,5, 5, 15, 30, 45 and 60 minutes. The results of the filtration in both filters (F1 and F2) were efficient in the removal of color (100%), turbidity (99%) and phosphate (40%). As the filtered molecules from F2 decreased from 68% of M. aeruginosa cells to 46% from those of F1. Residual values were 1.9 μg / L in AEF1 and 1.7 μg / L in AEF2. The use of POA (H2O2 / UV), a better dosage of H2O2 in AEF1 was 500 mM for the oxidation time of 60 minutes, allowing a lower concentration of MC-LR in this effluent (0.98 μg / L) after oxidative treatment. However, turbidity values are higher than 1.0%, while for AEF2 effluents and lower concentration of MC-LR (0.6 μg / L) was obtained with a dosage of 1000 mM H2O2 and oxidation of 60 minutes. The proposed treatment system for adhesive adsorption filtration is indicated for the application of PAM (UV / H2O2) and is effective in the elimination of M. aeruginosa and MC-LR toxin, regardless of the type of media used.