Remoção de micro-organismos patógenos de resíduos sépticos em leitos com e sem vegetação

Abstract

Septic wastes (SW) have high organic load and levels of pathogenic organisms, which limit their agricultural use or disposal in water bodies. So they should be adequately treated before the final disposal, preferably by simple and low cost technologies. This study aimed to compare the efficiency of constructed wetlands beds in the SW sanitation. Two cells were built, dug in the ground and filled with overlapping layers of gravel and sand for application and treatment of SW. One of the cells was cultivated by the plant specie Vetiver Grass (Chrysopogon zizanioides) and the other remained without vegetation. SW was applied to the surface of beds and evaluated their efficacy in the removal of pathogenic load by analysis of total coliforms, Escherichia coli, Salmonella spp. and viable helminth eggs. SW of pathogen removal efficiency in the treated liquid fraction was slightly higher in the bed with plants. Pathogen reduction from the sludge accumulated on the surface of the beds was slightly faster in the tank without vegetation.