Effect of influent COD/N ratio on performance and N2O emission of partial nitrification treating high-strength nitrogen wastewater

RSC Advances ◽  
2015 ◽  
Vol 5 (75) ◽  
pp. 61345-61353 ◽  
Author(s):  
Xinwen Zhang ◽  
Jian Zhang ◽  
Zhen Hu ◽  
Huijun Xie ◽  
Dong Wei ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Chemical Oxygen Demand ◽  
Nitrogen Removal ◽  
Oxygen Demand ◽  
High Strength ◽  
N2o Emission ◽  
Partial Nitrification

The effect of influent chemical oxygen demand/nitrogen (COD/N) ratio on nitrogen removal and nitrous oxide (N2O) emission during partial nitrification treating high-strength nitrogen wastewater was investigated.

scholarly journals Confirmation the optimal aeration parameters for nitrogen removal and nitrous oxide emission in wastewater ecological soil infiltration systems with brown earth

2019 ◽  
Vol 80 (1) ◽  
pp. 144-152 ◽  
Author(s):  
Yafei Sun ◽  
Junling Pang ◽  
Shiyao Wang ◽  
Tingting Tao ◽  
Xun Fu ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Nitrogen Removal ◽  
Emission Rate ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
N2o Emission ◽  
Aeration Rate ◽  
Soil Infiltration ◽  
Aeration Time ◽  
Domestic Wastewater Treatment

Abstract Nitrogen removal is an obstacle for the wide application of wastewater ecological soil infiltration (WESI) system in domestic wastewater treatment. In this study, matrix dissolved oxygen (DO), nitrogen removal and nitrous oxide (N2O) emission in aerated pilot WESI systems were investigated under different aeration times (1, 2, 3, 4 and 6 h/d) and aeration rates (1, 2, 3 and 4 L/min). The results showed that aerobic conditions in upper matrix and anoxic or anaerobic conditions in the subsequent matrix were developed in an aerated/non-aerated cycle at the optimal aeration condition of aeration time of 4 h/d and aeration rate of 3 L/min. Simultaneously, high removal efficiency of chemical oxygen demand (COD) (97.9%), NH4+-N (98.2%), total nitrogen (TN) (90.7%) and low N2O emission rate (13.2 mg/(m2 d)) were obtained. The results would provide optimal aeration parameters for application of intermittent aerated WESI systems.

Does intermittent aeration and/or an influent distributary affect nitrogen removal and nitrous oxide emission of an ecological soil wastewater infiltration system?

2019 ◽  
Vol 79 (7) ◽  
pp. 1417-1425 ◽  
Author(s):  
Yue Zhao ◽  
Zhiyu Zhang ◽  
Ziqi Li ◽  
Shiyao Wang ◽  
Chaoquan Tan ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Nitrogen Removal ◽  
Emission Rate ◽  
N2o Emission ◽  
Functional Genes ◽  
Intermittent Aeration ◽  
Anaerobic Conditions ◽  
N Removal ◽  
The Matrix ◽  
Removal Efficiencies

Abstract The effect of intermittent aeration and an influent distributary on NH4+-N removal, total nitrogen (TN) removal, nitrous oxide (N2O) emission and the abundances of nitrogen removal and N2O emission functional genes in four types of ecological soil wastewater infiltration systems (ESWISs) (which were conventional ESWIS 1 (operated without aeration and influent distributary), ESWIS 2 (operated with intermittent aeration), ESWIS 3 (operated with influent distributary) and ESWIS 4 (operated with intermittent aeration and influent distributary)) were studied. Intermittent aeration in ESWIS 2 and 4 created aerobic conditions above 50 cm depth of the matrix and anoxic or anaerobic conditions in the lower matrix (below 80 cm depth). ESWIS 4 improved NH4+-N (to 90.1%) and TN (to 87.8%) removal efficiencies and increased the abundances of eight nitrogen removal and N2O emission functional genes (amoA, nxrA, narG, napA, nirS, nirK, qnorB and nosZ) in contrast with other ESWISs. The combination of intermittent aeration and influent distributary achieved the lowest N2O emission rate of 34.7 mg/(m2 d) in ESWIS 4. Intermittent aeration combined with influent distributary was recommended for ESWISs to enhance nitrogen removal and reduce N2O emission.

Effects of chemical oxygen demand (COD)/N ratios on pollutants removal in the subsurface wastewater infiltration systems with/without intermittent aeration

2016 ◽  
Vol 73 (11) ◽  
pp. 2662-2669 ◽  
Author(s):  
Siyu Song ◽  
Jing Pan ◽  
Shiwei Wu ◽  
Yijing Guo ◽  
Jingxiao Yu ◽  
...  
Keyword(s):  
Chemical Oxygen Demand ◽  
Nitrogen Removal ◽  
Removal Rate ◽  
Oxygen Deficiency ◽  
Oxygen Demand ◽  
Ammonia Nitrogen ◽  
Intermittent Aeration ◽  
Oxidation Reduction ◽  
The Matrix ◽  
Pollutants Removal

The matrix oxidation reduction potential level, organic pollutants and nitrogen removal performances of eight subsurface wastewater infiltration systems (SWISs) (four with intermittent aeration, four without intermittent aeration) fed with influent chemical oxygen demand (COD)/N ratio of 3, 6, 12 and 18 were investigated. Nitrification of non-aerated SWISs was poor due to oxygen deficiency while higher COD/N ratios further led to lower COD and nitrogen removal rate. Intermittent aeration achieved almost complete nitrification, which successfully created aerobic conditions in the depth of 50 cm and did not change anoxic or anaerobic conditions in the depth of 80 and 110 cm. The sufficient carbon source in high COD/N ratio influent greatly promoted denitrification in SWISs with intermittent aeration. High average removal rates of COD (95.68%), ammonia nitrogen (NH4+-N) (99.32%) and total nitrogen (TN) (89.65%) were obtained with influent COD/N ratio of 12 in aerated SWISs. The results suggest that intermittent aeration was a reliable option to achieve high nitrogen removal in SWISs, especially with high COD/N ratio wastewater.

Treatment of anaerobically digested dairy manure in a two-stage biofiltration system

2012 ◽  
Vol 65 (11) ◽  
pp. 1975-1981 ◽  
Author(s):  
Mengjing Xia ◽  
Wendong Tao ◽  
Ziyuan Wang ◽  
Yuansheng Pei
Keyword(s):  
Chemical Oxygen Demand ◽  
Nitrogen Removal ◽  
Biochemical Oxygen Demand ◽  
Oxygen Demand ◽  
Dairy Manure ◽  
Ammonium Oxidation ◽  
Two Stage ◽  
Sand Filters ◽  
Soluble Chemical Oxygen Demand ◽  
Anaerobically Digested Dairy Manure

High concentrations of ammonium and phosphate present a challenge to cost-effective treatment of anaerobically digested dairy manure. This study investigated the efficacy of a two-stage biofiltration system for passive treatment of digested dairy manure. The first stage pebble filters were batch loaded. When the slurry-like digested dairy manure was retained on pebble beds, soluble contaminants were removed before liquid infiltrated over 8–17 days. The pebble filters removed 70% of soluble chemical oxygen demand, 71% of soluble biochemical oxygen demand, 75% of ammonium, and 68% of orthophosphate. Nitrogen removal was attributed to the conventional nitrification – denitrification process and novel nitritation – anammox process. Aerobic ammonium oxidizing and anammox bacteria accounted for 25 and 23% of all bacteria, respectively, in the filtrate of the pebble filters. The longer it took for filtration, the greater the removal efficiency of soluble contaminants. The second stage sand filters had removal efficiencies of 17% for soluble chemical oxygen demand, 45% for soluble biochemical oxygen demand, 43% for ammonium, and 16% for orthophosphate during batch operations at a hydraulic retention time of 7 days. Aerobic ammonium oxidation and anammox were primarily responsible for nitrogen removal in the sand filters. Vegetation made an insignificant difference in treatment performance of the sand filters.

Nitrogen removal and N2O emission by shunt distributing wastewater in aerated or non-aerated subsurface wastewater infiltration systems under different shunt ratios

2018 ◽  
Vol 78 (2) ◽  
pp. 329-338 ◽  
Author(s):  
Fanping Zheng ◽  
Yue Zhao ◽  
Zhiqi Li ◽  
Chaoquan Tan ◽  
Jing Pan ◽  
...  
Keyword(s):  
Nitrogen Removal ◽  
Emission Rate ◽  
Oxygen Demand ◽  
N2o Emission ◽  
Functional Gene ◽  
Intermittent Aeration ◽  
Oxidation Reduction ◽  
Oxidation Reduction Potential ◽  
Functional Gene Abundance ◽  
Combined Strategy

Abstract This study investigated matrix oxidation–reduction potential (ORP), nitrogen removal, N2O emission and nitrogen removal functional gene abundance in three subsurface wastewater infiltration systems (SWISs), named SWIS A (without aeration or shunt distributing wastewater), SWIS B (with shunt distributing wastewater) and SWIS C (with intermittent aeration and shunt distributing wastewater) under different shunt ratios. Aerobic conditions were produced at a depth of 50 cm and anoxic or anaerobic conditions were not changed at depths of 80 and 110 cm by aeration in SWIS C. High average removal rates of chemical oxygen demand (COD) (83.1% for SWIS B, 90.9% for SWIS C), NH3-N (74.3% for SWIS B, 90.8% for SWIS C) and total nitrogen (TN) (61.1% for SWIS B, 87.9% for SWIS C) were obtained under shunt ratios of 1:3 and 1:2 for SWIS B and C, respectively. The lowest N2O emission rate (28.4 mg/(m2 d)) and highest nitrogen removal functional gene abundances were achieved in SWIS C under a 1:2 shunt ratio. The results suggested intermittent aeration and shunt distributing wastewater combined strategy would enhance nitrogen removal and reduce N2O emission for SWISs.

scholarly journals Biological treatment of leachate from stabilization of biodegradable municipal solid waste in a sequencing batch biofilm reactor

2020 ◽  
Author(s):  
K. Bernat ◽  
M. Zaborowska ◽  
M. Zielińska ◽  
I. Wojnowska-Baryła ◽  
W. Ignalewski
Keyword(s):  
Municipal Solid Waste ◽  
Chemical Oxygen Demand ◽  
Solid Waste ◽  
Oxygen Content ◽  
Total Nitrogen ◽  
Nitrogen Removal ◽  
Biochemical Oxygen Demand ◽  
Oxygen Demand ◽  
Synthetic Wastewater ◽  
Total Nitrogen Removal

Abstract The aim of this study was to determine the effectiveness of pollutant removal in sequencing batch biofilm reactors (with floating or submerged carriers) when treating nitrogen- and organic-rich real leachate generated during aerobic stabilization of the biodegradable municipal solid waste. A control reactor contained suspended activated sludge. The share of leachate in synthetic wastewater was 10%, which resulted in ratios of chemical oxygen demand and biochemical oxygen demand to total Kjeldahl nitrogen in the influent of ca. 11 and ca. 8.5, respectively. Regardless of whether the reactors contained carriers or not, the effectiveness of nitrification (84.2–84.3%) and of the removal of chemical oxygen demand (86.5–87.0%), biochemical oxygen demand (95.5–98.0%) and ammonium (88.9–89.3%) did not differ. However, the presence of carriers and their type determined in which phase of the cycle denitrification occurred. In the control reactor, denitrification took place during mixing phase with the effectiveness of ca. 43.2% (57.7% of the total nitrogen removal). During aeration, the oxygen content increased rapidly, thus reduced the possibility of simultaneous denitrification. In reactors with carriers, in the aeration phase, not only nitrification but also denitrification occurred. The increase in oxygen content in wastewater was slower, which could have caused dissolved oxygen gradients and anoxic zones in deeper layers of the biofilm and flocks. In the reactor with floating carriers, the effectiveness of denitrification and total nitrogen removal increased 1.23- and 1.10-times, respectively, as compared to the control reactor. The highest efficiencies (67.7% and 73.0%, respectively) were observed in the reactor with submerged carriers.

Enhanced simultaneous nitri-denitrification in aerobic moving bed biofilm reactor containing polyurethane foam-based carrier media

2019 ◽  
Vol 79 (3) ◽  
pp. 510-517 ◽  
Author(s):  
Magdum Sandip ◽  
V. Kalyanraman
Keyword(s):  
Chemical Oxygen Demand ◽  
Nitrogen Removal ◽  
Oxygen Demand ◽  
Biofilm Reactor ◽  
Moving Bed Biofilm Reactor ◽  
Moving Bed ◽  
Removal Capacity ◽  
Pu Foam ◽  
Removal Efficiencies ◽  
Biofilm Support

Abstract Fluidization of carrier media for biofilm support and growth defines the moving bed biofilm reactor (MBBR) process. Major MBBR facilities apply virgin polyethylene (PE)-based circular plastic carrier media. Various carriers were studied to replace these conventional carriers, but polyurethane (PU) foam-based carrier media has not been much explored. This study evaluates the potential of PU foam carrier media in aerobic MBBR process for simultaneous nitri-denitrification (SND). Two parallel reactors loaded with conventional PE plastic (circular) and PU foam (cubical) carriers compared for their removal efficiencies of chemical oxygen demand (COD) and nitrogen contaminants from wastewater. Results indicate that average COD removal in MBBR containing PE plastic carrier media was 81%, compared to 83% in MBBR containing PU foam. Average ammonical and total nitrogen reduction was 71% and 59% for PU foam-based MBBR, compared to 60% and 42% for PE plastic-based MBBR. SND-based nitrogen removal capacity was doubled in aerobic MBBR filled with PU foam carrier media (27%), than MBBR containing PE plastic carrier media (13%). Cost economics also governs the commercial advantage for the application of PU foam-based carrier media in the MBBR process.

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