Biological Diversity in Aerated Facultative Lagoon Treating Kraft Cellulose Effluent Through Bioaugmentation

Background: This study analyzes the microbiological diversity in an aerated facultative lagoon system with volumetric organic loading rates of 0.2 and 0.6 kgCODm-3d-1 treating effluent from the kraft pulp industry through bioaugmentation. The samples for the study of biological diversity were taken from a laboratory-scale lagoon at steady state treating kraft pulp effluent and operated with 0.2 and 0.6 kgCODm-3d-1 for 120 days. This analysis was performed by identifying the 16s DNA sequencing, through DNA extraction, polymerase chain reaction and agarose gel electrophoresis at 1%. Next, the autochthonous bacteria were named through statistical similarity obtained from the National Center for Biotechnology Information database. The lagoon performance was assessed based on the removal efficiency of specifics compounds.Results: In the biomass samples collected at steady state, 9 and 12 species of bacteria were identified and the species Bacillus cereus, Bacillus thuringiensis and Paenibacillus glucanolyticus found in this matrix presented significant removal of the parameters in the kraft effluent. In the treatment, it was possible to observe that the removal of organic matter above 50% for chemical demand and above 95% for biochemical demand. The specific compounds were not significantly removed, but this is a characteristic of biological treatments. Conclusions: We found that the three referred species show great promise in the removal of specific parameters in a lagoon biological treatment system using bioaugmentation.