Development of a Flow-through Biofilm Reactor for Anammox Startup and Operation: Nitrogen Removal and Metacommunity

Abstract

A well-designed flow-through biofilm reactor (FTBR) serving as both a biofilter and a biofilm carrier was developed to effectively retain anammox bacteria within threedimensional honeycomb-like textile structures in the anammox process. The bioreactor performance and microbiological properties were investigated under three different fluxes during a period of 160 days. Appreciable biomass aggregates were developed to enhance the nitrogen removal. Accordingly, proper turbidity (≤1 NTU) and nitrogen removal were consistently achieved, in which the FTBR achieved nitrogen removal rates (NRRs) of 0.450 and 0.706 g-N/(L•d) under the nitrogen loading rates (NLRs) of 0.503 and 0.751 g-N/(L•d), respectively. Nitrogen was removed after penetrating the biofilm, and a larger imposed flux on modules resulted in higher nitrogen removal due to the formation of different microenvironments. While the imposed flux increased, the relative abundances of the anammox group increased from 5.23% to 8.12%, whereas the ones of denitrifiers decreased and the ones of ammonium oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) did not change significantly. Of the two dominant anammox species, the abundance of Candidatus Kuenenia decreased, whereas the abundance of Candidatus Jettenia increased with increasing flux. Compared to the freely grown biofilm, bacterial communities of flow-through modules showed greater ecological niche differentiation and enhanced mass transport efficiency among species. The developed FTBR system is effective for anammox system startup and optimizing partial nitritation−anammox processes.

State-Space-Based Framework for Predicting Microbial Interaction Variability in Wastewater Treatment Plants

“…The global dataset has to a great extent provided us with all the possible states of the AS community, which confers an advantage for our prediction of possible community shifts. To further assess the predictive power of our approach, we have collected 599 samples of lab-scale anammox reactors to investigate the microbial interaction variability in the anammox community. − Raw sequences of the microbial communities are available from the NCBI Sequence Read Archive with accession numbers PRJNA509305, PRJNA324303, PRJNA419809, PRJNA516998, PRJNA593169, PRJNA640337, PRJNA593167, SUB4528727, and PRJNA397254.…”

Host–Endosymbiont Relationship Impacts the Retention of Bacteria-Containing Amoeba Spores in Porous Media

“…Detailed procedures are reported in the Supporting Information. 52,53 ■ RESULTS AND DISCUSSION Characterization of Spores. As demonstrated by the confocal microscopy images, the prepared amoeba spores were successfully infected by B. agricolaris (Figure 1).…”

“…The supernatant was directly transferred to the mass spectrometer (Thermo Scientific Q Exactive) for online detection over a mass range of 300–1800 m / z at a resolution of 70 000. Detailed procedures are reported in the Supporting Information. , …”

Development of Warp Knitted-Based Filtration Media

“…[32] published a paper comparing the efficiencies of a carrier made of warp knitted fabric (i.e., microcarrier), a textile carrier with functional nanocoating (i.e., nanocarrier), and a classical AnnoxKaldnes plastic carrier. [33] employed three-dimensional (3D) honeycomb-like textile structures fabricated through the warp knitting technology using a flow-through biofilm reactor for the anammox system startup and by optimizing partial nitritation. The design of the biomass carrier for the wastewater treatment from nitrogen compounds is based on the functional property requirements of a carrier and considers the size, thickness, shape, and possibilities of hole creation in a carrier.…”