Response of wastewater treatment performance, microbial composition and functional genes to different C/N ratios and carrier types in MBBR inoculated with heterotrophic nitrification-aerobic denitrification bacteria

Pilot study on the filling rate of parallel AA‐MBBR fillers in plateau areas

“…At the genus level (Figure 6) the microbial composition of denitrifying bacteria genera were the most abundant and the highest relative abundance were all belonging to denitrifying bacteria Rhodanobacter (13.15%), norank_f__AKYH767 (11.20%) and Ottowia (5.52%), followed by for example, norank_f__Comamonadaceae (5.54%) of polyphosphate bacteria, which further enhanced the N and P removal. There were fewer species of denitrifying bacterial genera in this study, whereas in the study of Zhu Jiaxin et al a variety of denitrifying functional bacterial genera were found to exist in the MBBR reactor, 34 which was analyzed as the reason that the higher UV intensity of the plateau would have a damaging effect on the microbial nucleoproteins and DNA, and that some of the microorganisms would be inhibited or even eliminated under the selection of the strong UV conditions 35,36 . From this figure, it can also be seen that with the increase of filling rate, the relative abundance of denitrifying bacteria as a whole also gradually increased and showed a trend of first increase and then decrease and reached the highest at TCL40, which was consistent with the trend of the average TN removal rate, which was due to the appropriate increase in the filling rate to increase the filler's specific surface area and thus provide an excellent environment for the growth of denitrifying bacteria, which promoted the growth of denitrifying bacteria, which then improved the TN removal rate, and also provided an excellent growth environment for the denitrifying bacteria.…”

Solving the problem of high concentration aniline inhibiting nitrogen removal: starting the SBBR with the prolonged aeration mode

“…Another reason may be heterotrophic nitrification and aerobic denitrification in the activated sludge system. Chen et al 's 30 research has proved that heterotrophic nitrification–aerobic denitrification bacteria played an underlying role of nitrogen removal in the treatment system of aniline wastewater or azo dye acid wastewater.…”

Designing efficient floating bed options for the treatment of eutrophic water

“…PAST software was used to construct Shannon-Weiner, Simpson inverse Simpson, and Fisher alpha to show and compare the species richness and evenness of both water samples. The alpha diversity index is generally calculated using the Shannon index, but the Simpson index provides a sufficient number of genera to reflect environmental heterogeneity (Chen et al 2021). The PCA plot was developed to analyze the taxonomic diversity as well as the difference in abundance associated with both samples for a better understanding of the comparison between the best-performing reactor studies (Breda et al 2017).…”