Comparison between a moving bed membrane bioreactor and a conventional membrane bioreactor on organic carbon and nitrogen removal

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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Modeling dynamics of organic carbon and nitrogen removal during aeration interruption in aerated horizontal flow treatment wetlands

Water Science & Technology ◽

10.2166/wst.2019.304 ◽

2019 ◽

Vol 80 (3) ◽

pp. 597-606 ◽

Cited By ~ 1

Author(s):

Johannes Boog ◽

Thomas Kalbacher ◽

Jaime Nivala ◽

Manfred van Afferden ◽

Roland A. Müller

Keyword(s):

Steady State ◽

Organic Carbon ◽

Dynamic Response ◽

Nitrogen Removal ◽

Oxygen Demand ◽

Ammonia Nitrogen ◽

Treatment Wetlands ◽

Horizontal Flow ◽

Simulation Accuracy ◽

Carbon And Nitrogen

Abstract Despite recent developments in process-based modeling of treatment wetlands (TW), the dynamic response of horizontal flow (HF) aerated wetlands to interruptions of aeration has not yet been modeled. In this study, the dynamic response of organic carbon and nitrogen removal to interruptions of aeration in an HF aerated wetland was investigated using a recently-developed numerical process-based model. Model calibration and validation were achieved using previously obtained data from pilot-scale experiments. Setting initial concentrations for anaerobic bacteria to high values ( 35–70 mg L−1) and including ammonia sorption was important to simulate the treatment performance of the experimental wetland in transition phases when aeration was switched off and on again. Even though steady-state air flow rate impacted steady-state soluble chemical oxygen demand (CODs), ammonia nitrogen (NH4–N) and oxidized nitrogen (NOx–N) concentration length profiles, it did not substantially affect corresponding effluent concentrations during aeration interruption. When comparing simulated with experimental results, it is most likely that extending the model to include mass transfer through the biofilm will allow to better explain the underlying experiments and to increase simulation accuracy. This study provides insights into the dynamic behavior of HF aerated wetlands and discusses assumptions and limitations of the modeling approach.

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Phosphorus and Nitrogen Removal in Moving-Bed Sequencing Batch Biofilm Reactors

Water Science & Technology ◽

10.2166/wst.1999.0589 ◽

1999 ◽

Vol 40 (4-5) ◽

pp. 169-176 ◽

Cited By ~ 28

Author(s):

Giuseppe Pastorelli ◽

Roberto Canziani ◽

Luca Pedrazzi ◽

Alberto Rozzi

Keyword(s):

Organic Carbon ◽

Nitrogen Removal ◽

Municipal Wastewater ◽

Phosphorus Uptake ◽

Biofilm Reactor ◽

Municipal Wastewater Treatment ◽

Biological Phosphorus Removal ◽

Nitrogen And Phosphorus ◽

Limit Values ◽

Moving Bed

A pilot moving-bed sequencing batch biofilm reactor (MBSBBR) fed with primary settled wastewater, was used in order to study organic carbon, phosphorus and nitrogen removal with and without external carbon sources. Patented KMT® polyethylene biofilm carriers were used. Organic carbon uptake and phosphorus release has been achieved in the anaerobic phase of the cycle, while nitrification, simultaneous denitrification (i.e., anoxic respiration of sequestered COD in the inner layer of the biofilm) and phosphorus uptake was observed in the aerobic phase. A stable biological phosphorus removal could be achieved only with an external carbon source. Since the process proved flexible and reliable, it is suitable for full scale application to municipal wastewater treatment plants (WWTPs), in order to meet EU total nitrogen and phosphorus limit values for discharge into sensitive receiving waters.

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