A Study on Organic Carbon and Nitrogen Removal by Sulfate Reduction and Sulfur Denitrification Process.

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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Effects of C/N, C/S and S/N ratios on TOC and nitrogen removal in the sulfate reduction-sulfur denitrification process

Journal of Water and Environment Technology ◽

10.2965/jwet.2003.7 ◽

2003 ◽

Vol 1 (1) ◽

pp. 7-12 ◽

Cited By ~ 4

Author(s):

Ryoko YAMAMOTO-IKEMOTO ◽

Tomoaki KOMORI

Keyword(s):

Sulfate Reduction ◽

Nitrogen Removal ◽

Denitrification Process

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Effect of Hydraulic Retention Time on Pretreatment of Sulfate-Laden Wastewater for Desulfurization-Denitrification Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.113-116.536 ◽

2010 ◽

Vol 113-116 ◽

pp. 536-539

Author(s):

Wei Li ◽

Xiao Liang ◽

Jian Guo Lin

Keyword(s):

Organic Carbon ◽

Sulfate Reduction ◽

Retention Time ◽

Hydraulic Retention Time ◽

Removal Rate ◽

Reduction Stage ◽

Sulfate Removal ◽

Carbon Sulfide ◽

Set Up ◽

Denitrification Process

In order to treat wastewater rich in sulfate and organic carbon, an anaerobic attached-growth bioreactor was set up. It was the pretreatment of desulfurization-denitrification process. At hydraulic retention time of 128h-6.2h, sulfate removal rate and sulfide generating rate took on initial increasing and subsequent decreasing. At hydraulic retention time of 7.7h-10.2h, the removals of sulfate and organic carbon, sulfide generating rate reached 95.79%, 80% and 58.82%, respectively. The results showed that the suitable hydraulic retention time in sulfate reduction stage for the pretreatment of desulfurization-denitrification process was 7.7h-10.2h.

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