These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: [Effect of the Influent C/P Ratio on the Nutrient Removal Characteristics of the SNEDPR System]. Author: Zhen JY, Yu DS, Wang XX, Chen GH, Du YQ, Yuan MF, Du SM. Journal: Huan Jing Ke Xue; 2019 Jan 08; 40(1):343-351. PubMed ID: 30628292. Abstract: This study focuses on the nitrogen (N) and phosphorus (P) removal characteristics in a simultaneous nitrification-endogenous denitrification and phosphorus removal (SNEDPR) system at different influent C/P ratios. An extended anaerobic/low aerobic (dissolved oxygen:0.5-1.0 mg·L-1) sequencing batch reactor (SBR) fed with municipal sewage was studied by adjusting different C/P ratios (10, 15, 20, 30, and 60). The experimental results show that the proper reduction of the influent C/P ratio (C/P ratio reduced from 60 to 30) enhances the competitive advantages of phosphorus-accumulating organisms (PAOs) in the SNEDPR system. The highest phosphorus removal efficiency was achieved at a C/P ratio of 30, with the anaerobic phosphorus release rate (PRR) and aerobic phosphorus uptake rate (PUR, used as P/MLSS) reaching 3.5 mg·(g·h)-1 and 4.2 mg·(g·h)-1 respectively, and an average effluent PO43--P concentration below 0.3 mg·L-1. The percentage of PAOs contributing to the storage of endogenesis carbon (PPAO, An) reached 88.1%. However, a poor phosphorus removal performance was observed with further reduction of the influent C/P ratios to 10; both the PO43--P removal efficiency and PPAO, An decreased from 38.1% and 82.4% to 3.1% and 5.3%, respectively. The PRR and PUR were 0.2 mg·(g·h)-1 and 0.24 mg·(g·h)-1, respectively. The COD removal performance was not affected by the decreasing influent C/P ratios; the average COD removal efficiency stabilized at 85%. In addition, the nitrification performance became worse with decreasing C/P ratios (from 60 to 20) because the effluent NH4+-N and NO2--N concentrations increased from 0 and 6.9 mg·L-1 to 5.1 mg·L-1 and 16.2 mg·L-1, respectively. The nitrificaton performance recovered when the C/P ratios further decreased to 10, but the nitrite accumulation was disturbed as both the effluent NH4+-N and NO2--N concentrations reduced to 0. The effluent NO3--N concentration increased from 0.08 mg·L-1 to 14.1 mg·L-1. The SNED efficiency first decreased from 62.1% to 36.4% and then increased to 56.4%. The advantageous competition of glycogen accumulating organisms (GAOs) improved when the influent C/P ratio was lower than 15. The enhancement of the endogenous denitrification ability of GAOs might explain the recovery denitrification performance of the system when the influent C/P ratios decreased from 20 to 10.[Abstract] [Full Text] [Related] [New Search]