Metabolic products comparison in autotrophic and heterotrophic nitrogen removal: Insights into membrane fouling.

Metabolic products play a significant role in membrane fouling during biological wastewater treatment. However, the differences in metabolic product composition and membrane fouling potentials between autotrophic (anammox, AN) and heterotrophic (denitrification, DN) nitrogen removal systems are not well understood. This study cultivated autotrophic and heterotrophic nitrogen removal systems and analyzed the compositions of their metabolic products.

Typical Heterotrophic and Autotrophic Nitrogen Removal Process Coupled with Membrane Bioreactor: Comparison of Fouling Behavior and Characterization.

There is limited research on the relationship between membrane fouling and microbial metabolites in the nitrogen removal process coupled with membrane bioreactors (MBRs). In this study, we compared anoxic-oxic (AO) and partial nitritation-anammox (PNA), which were selected as representative heterotrophic and autotrophic biological nitrogen removal-coupled MBR processes for their fouling behavior. At the same nitrogen loading rate of 100 mg/L and mixed liquor suspended solids (MLSS) concentration of 4000 mg/L, PNA-MBR exhibited more severe membrane fouling compared to AO-MBR, as evidenced by monitoring changes in transmembrane pressure (TMP).

Exploring transformation of dissolved organic matters and dissolved organic nitrogen in full-scale anammox wastewater treatment: Temperature and microbial roles.

Variation of dissolved organic matters (DOM) in mainstream anammox process has received limited attention. This study systematically characterized DOM and dissolved organic nitrogen (DON) in a full-scale mainstream anammox wastewater treatment plant (WWTP) using spectroscopy and Fourier transform-ion cyclotron resonance mass spectrometry. Roles of bacterial community structures related with temperatures on DOM and DON transformations were analyzed.