Insight into short-cut of simultaneous nitrification and denitrification process in moving bed biofilm reactor: Effects of carbon to nitrogen ratio

The paper presents research of a prototype moving bed biofilm reactor (MBBR). The device was used for the post-denitrification process and was installed at the end of a technological system consisting of a septic tank and two trickling filters. The concentrations of suspended biomass and biomass attached on the EvU Perl moving bed surface were determined. The impact of the external organic carbon concentration on the denitrification rate and efficiency of total nitrogen removal was also examined. The study showed that the greater part of the biomass was in the suspended form and only 6% of the total biomass was attached to the surface of the moving bed. Abrasion forces between carriers of the moving bed caused the fast stripping of attached microorganisms and formation of flocs. Thanks to immobilization of a small amount of biomass, the MBBR was less prone to leaching of the biomass and the occurrence of scum and swelling sludge. It was revealed that the maximum rate of denitrification was an average of 0.73 gN-NO3/gDM·d (DM: dry matter), and was achieved when the reactor was maintained in external organic carbon concentration exceeding 300 mgO2/dm3 chemical oxygen demand. The reactor proved to be an effective device enabling the increase of total nitrogen removal from 53.5% to 86.0%.

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Enhanced simultaneous nitrification and denitrification in treating low carbon-to-nitrogen ratio wastewater: Treatment performance and nitrogen removal pathway

Bioresource Technology ◽

10.1016/j.biortech.2019.02.022 ◽

2019 ◽

Vol 280 ◽

pp. 51-58 ◽

Cited By ~ 23

Author(s):

Hongxiang Chai ◽

Yu Xiang ◽

Rong Chen ◽

Zhiyu Shao ◽

Li Gu ◽

...

Keyword(s):

Wastewater Treatment ◽

Nitrogen Removal ◽

Simultaneous Nitrification And Denitrification ◽

Low Carbon ◽

Carbon To Nitrogen Ratio ◽

Treatment Performance ◽

Nitrogen Ratio ◽

Nitrification And Denitrification

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Effect of Carbon Nitrogen Ratio on Simultaneous Nitrification and Denitrification via Nitrite Technology in Sequencing Batch Biofilm Reactor and the Process Control

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.777.232 ◽

2013 ◽

Vol 777 ◽

pp. 232-237 ◽

Cited By ~ 1

Author(s):

Hui Wei Zhao ◽

Ke Fang Zhang ◽

Hong Wei Rong ◽

Chao Sheng Zhang ◽

Zhi Wen Yang

Keyword(s):

Process Control ◽

Removal Efficiency ◽

Removal Rate ◽

Control Point ◽

Biofilm Reactor ◽

Nitrite Accumulation ◽

Simultaneous Nitrification And Denitrification ◽

Carbon Nitrogen Ratio ◽

Nitrogen Ratio ◽

Nitrification And Denitrification

This study aimed to evaluate the effect of carbon nitrogen ratio (COD/N) on simultaneous nitrification and denitrification (SND) via nitrite technology in SBBR and the process control. Under the condition of different C/N ratios respectively 1.8, 3.6, 7,5,11.1 and 13.7, the various indices of the removal efficiency in the system and DO, ORP, and pH in the process of reaction were investigated. The C/N ratio was found to be an important limiting factor for SBBR simultaneous nitrification and denitrification via nitrite process. After integrating the factor of energy consumption and removal efficiency, we obtained that the optimum C/N ratios control range from 7.5 to 11.1, reaction time was between 225 min and 315 min, nitrite accumulation rate was between 72.83 % and 78.7 %, COD removal rate was between 92.31 % and 93.08 %, the total nitrogen removal rate was between 81.0 % and 85.86 %. For steady-state simultaneous nitrification and denitrification via nitrite process in SBBR, the jump point (C) on the DO, pH and ORP curve at reaction later period can be used as a control point to indicate the end of the reaction.

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