Science News

Improved membrane sequencing batch reactor: effect of carbon and nitrogen volumetric loading rate on dephosphatation.

A new interesting article has been published in Environ Technol. 2018 Oct 19:1-19. doi: 10.1080/09593330.2018.1537304. [Epub ahead of print] and titled:

Improved membrane sequencing batch reactor: effect of carbon and nitrogen volumetric loading rate on dephosphatation.

Authors of this article are:

Xu X, Zhong P, Zhang C, Yuan L, Sun G, Qian Y, Liang H.

A summary of the article is shown below:

A lab-scale anaerobic-anoxic-aerobic membrane bioreactor (A2NO-MBR) fed with synthetic wastewater was operated to investigate the impact of influent carbon and nitrogen volumetric loading rate (VLR) on dephosphatation, and the corresponding influent concentration was 100-300 mg·L-1 (COD), 24-50 mg·L-1 (NH4+-N) and 4.8-6.0 mg·L-1 (TP), respectively. The results demonstrated that carbon VLR had a negligible effect on the COD removal with effluent below 50 mg·L-1, and high and stable removal capacity for phosphorus were also obtained, regardless of carbon VLR change. Whereas, TN removal efficiency was positively correlated with carbon VLR reduction, and lower carbon VLR produced negative effect on TN removal. In addition, since nitrate served as electron acceptor for denitrifying phosphorus removal (DPR), a significant effect on nitrogen and phosphorus removal was observed with different nitrogen VLR. The TN and TP removal efficiency was 68.30 ± 1.36%, 70.70 ± 1.23%, 45.19 ± 1.72% and 41.63 ± 3.09%, 98.14 ± 0.53%, 53.34 ± 2.68% with influent nitrogen VLR of 0.024 ± 0.001, 0.034 ± 0.001 and 0.045 ± 0.001 Kg-N/(m3·d), respectively. Moreover, bacterial community structure of sludge samples in Run I and V from anaerobic-anoxic-aerobic-SBR (named A2OSBR_1 and A2OSBR_2) and membrane bioreactor (named N-MBR_1 and N-MBR_2) revealed that Candidatus_Accumulibacter was the most dominant genus in A2OSBR_1 (21.50%) and A2OSBR_2 (18.98%). The relative lower carbon VLR favoured the enrichment of Saprospiraceae, which was related with DPR, with the proportion of 9.31% and 14.61% in A2OSBR_1 and A2OSBR_2. Besides, Nitrospira and Nitrosomonas with proportions of 11.14%, 5.38% in N-MBR_1 and 10.72%, 6.77% in N-MBR_2 were observed, which were likely responsible for the nearly complete nitrification.

Check out the article’s website on Pubmed for more information:



This article is a good source of information and a good way to become familiar with topics such as:

Denitrifying phosphorus removal;carbon volumetric loading rate;community structure;membrane bioreactor;nitrogen volumetric loading rate

.

Categories: Science News