Biological conversion of nitrate in packed bed organic material reactors

• DOI: https://doi.org/10.22533/at.ed.3174262401112

• Palavras-chave: Effluent; Malt Bark; Wood Chip; Heterotrophic Bacteria; Nitrogen Removal.

• Keywords: Effluent; Malt Bark; Wood Chip; Heterotrophic Bacteria; Nitrogen Removal.

• Abstract:

  With the growth of the timber and brewing industries, the production of waste such as malt bark and wood chips has increased, as has the generation of their respective effluents, which can be harmful because they are rich in nitrate, an essential nutrient for algae, and can therefore generate eutrophication. In order to remove nitrate, conventional reactors have two compartments, one for nitrification and the other for denitrification. With the aim of converting nitrate into molecular nitrogen and advancing research into reactors that promote nitrification and denitrification in a single reactor, this study was carried out to evaluate the possibility of using malt bark and wood chips as a carbon source and support medium in the process of biological conversion of nitrate into gaseous nitrogen. This research consisted of two phases, the first to fix the microorganisms in the bioreactor and the second to treat the effluent. In phase 1, samples were taken every 24 hours in order to visualize the inoculation through nitrate and chemical oxygen demand analysis, while phase 2 consisted of samples taken every 12 hours and comparisons of nitrate removal were made. After phase 2, the reactors and carbon sources were compared, after which nitrate removals of over 58% were achieved for the chip and over 65% for the malt husk. With these results, it is concluded that the sources are viable as a carbon source for the biological conversion of nitrate in NDS reactors.