A new method for in-situ treatment of waste gas scrubbing liquid containing both NH3 and H2S based on sulfur autotrophic denitrification and partial nitrification-Anammox coupling system.

Abstract In this study, an integrated device with scrubbing and biochemical treatment functions was used, and partial nitrification (PN)-Anammox and sulfur autotrophic denitrification (SADN) processes were coupled in a biochemical treatment pond to explore the feasibility of in-situ autotrophic removal of NH3 and H2S. The results showed that the removal efficiency of NH3 and H2S in waste gas are 95% and 87.5% respectively. The scrubbing liquid was efficiently treated in the biochemical treatment pond. Nitrogenous compounds weren’t accumulated in liquid and converted to N2 by SADN and PN-Anammox coupling system. S2− was mainly used by SADN process to reduce NO3−. The scrubbing liquid processed by the biochemical treatment pond was refluxed to the scrubber to achieve continuous absorption of NH3 and H2S. Microbial community and functional microbial analysis showed that the PN-Anammox and SADN processes were the main processes to achieve the conversion of pollutants in the scrubbing liquid.