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PubMed · 16459819

Simultaneous nitrification and de-nitrification in MBR.

B Wang·S He·L Wang·L Shuo
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Abstract

Experiments have been carried out to get an understanding of the effect of DO, C/N ratio and pH on the performance of a bench scale membrane bioreactor (MBR) in simultaneous nitrification and denitrification. It was found that under the conditions of MLSS in the range of 8000-9000 mg/L and temperature of water in the MBR of 24 degrees C, influent COD and NH3-N in the range of 523-700 mg/L and 17.24-24 mg/L respectively, the removals of COD, NH3-N and TN were 98%, 99% and 60%; 96.5%, 0,98% and 75%; 96%, 95% and 92%; 90%,70% and 60% respectively at DO of 6, 3, 1 and 0.5 mg/L. It was also found that the changes in C/N ratio and pH in a certain range have a slight effect on COD removal but have significant influence on the removal of NH3-N and TN. The results showed that only under the conditions that each ecological factor was maintained relatively steadily, simultaneous nitrification and de-nitrification proceeded smoothly. It was found that when C/N ratio was 30, the influent pH 7.2, the temperature of water in MBR 24 degrees C and DO 1 mg/L, as optimum conditions, the removals of COD, NH3-N and TN were 96%, 95% and 92% respectively. In addition, mechanism research on simultaneous nitrification and de-nitrification in MBR has been conducted as well.

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AmmoniaBiodegradation, EnvironmentalBioreactorsCarbonHydrogen-Ion ConcentrationMembranes, ArtificialNitritesNitrogenOxygenSewageTemperatureTime FactorsWaste Disposal, FluidWater PurificationJournal Article

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B Wang, S He, L Wang, L Shuo. 2005. Simultaneous nitrification and de-nitrification in MBR.. https://pubmed.ncbi.nlm.nih.gov/16459819/

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