Critical Analysis of Biomass Retention Strategies in Mainstream and Sidestream ANAMMOX-Mediated Nitrogen Removal Systems

2020 ◽  
Vol 55 (1) ◽  
pp. 9-24
Author(s):  
Kiprotich Kosgey ◽  
Kartik Chandran ◽  
Jashan Gokal ◽  
Sammy Lewis Kiambi ◽  
Faizal Bux ◽  
...  
Keyword(s):  
Nitrogen Removal ◽  
Critical Analysis ◽  
Retention Strategies ◽  
Biomass Retention

Research on Nitrogen Removal Performance of Leachate Treatment of WSIP Reactor

2011 ◽  
Vol 55-57 ◽  
pp. 789-795
Author(s):  
Xiu Ju Duan ◽  
Qiang He ◽  
Ya Li Liu
Keyword(s):  
Nitrogen Removal ◽  
Biological Treatment ◽  
Orthogonal Experiment ◽  
Ammonia Nitrogen ◽  
Ammonia Removal ◽  
Leachate Treatment ◽  
Treatment Performance ◽  
Biomass Retention ◽  
Nitrification And Denitrification

This thesis put forward the treatment concept of “without Biomass Retention Sequential Batch Intensified Pretreatment (WSIP)” in leachate treatment, for sake of improving performance of nitrogen removal, optimizing excess water’s nutritional ratio and benefitting the follow-up aerobic biological treatment. Based on orthogonal experiment of WSIP Reactor’s leachate treatment performance, Conclusions can be drew: the removal performance of ammonia nitrogen and TN is higher of WSIP, in which short-cut nitrification and denitrification can be realized; HRT, DO and sequential period are remarkable factors of ammonia removal performance, TN removal performance and realization of short-cut nitrification and denitrification; In normal temperature, the most perfect functional parameter of WSIP Reactor is: HRT=4d, DO=0.75mg/L and sequential period is 6h.

Evaluating fixed-film nitrification systems in autotrophic mode: Enhanced biomass retention does not improve bioreactor performance during alkalinity induced stress

2022 ◽  
Author(s):  
Evan Ronan ◽  
Otini Kroukamp ◽  
Steven N Liss ◽  
Gideon Wolfaardt
Keyword(s):  
Nitrogen Removal ◽  
Biofilm Formation ◽  
Environmental Stressors ◽  
Biological Nitrogen Removal ◽  
Process Stability ◽  
Induced Stress ◽  
Fixed Film ◽  
Biomass Retention ◽  
Biological Nitrogen ◽  
Bioreactor Performance

Use of fixed-film systems has shown promise towards improving the process stability of biological nitrogen removal (BNR). It allows for biofilm formation, which can offer enhanced resilience to environmental stressors...

Nitrogen removal from sludge reject water by a two-stage oxygen-limited autotrophic nitrification denitrification process

2004 ◽  
Vol 49 (5-6) ◽  
pp. 57-64 ◽  
Author(s):  
S. Wyffels ◽  
P. Boeckx ◽  
K. Pynaert ◽  
D. Zhang ◽  
O. Van Cleemput ◽  
...  
Keyword(s):  
Nitrogen Removal ◽  
Anaerobic Ammonium Oxidation ◽  
Nitrite Accumulation ◽  
Autotrophic Denitrification ◽  
Ammonium Oxidation ◽  
Partial Nitritation ◽  
Reject Water ◽  
Biomass Retention ◽  
Volumetric Loading ◽  
Denitrification Process

Nitrogen removal from sludge reject water was obtained by oxygen-limited partial nitritation resulting in nitrite accumulation in a first stage, followed by autotrophic denitrification of nitrite with ammonium as electron donor (similar to anaerobic ammonium oxidation) in a second stage. Two membrane-assisted bioreactors (MBRs) were used in series to operate with high sludge ages and subsequent high volumetric loading rates, achieving 1.45 kg N m-3 day-1 for the partial nitritation MBR and 1.1 kg N m-3 day-1 for the anaerobic ammonium oxidation MBR. Biomass retention in the nitritation stage ensured flexibility towards loading rate and operating temperature. Nitrite oxidisers were out-competed at low oxygen and high free ammonia concentration. Biomass retention in the second MBR prevented wash-out of the slowly growing bacteria. Nitrite and ammonium were converted to dinitrogen gas in a reaction ratio of 1.05, thereby maintaining nitrite limitation to assure process stability. The anoxic consortium catalysing the autotrophic denitrification process consisted of Nitrosomonas-like aerobic ammonium oxidizers and anaerobic ammonium oxidizing bacteria closely related to Kuenenia stuttgartiensis. The overall removal efficiency of the combined process was 82% of the incoming ammonium according to a total nitrogen removal rate of 0.55 kg N m-3 day-1, without adding extra carbon source.

379: A Critical Analysis of the Interpretation of Biochemical Recurrence in Surgically Treated Patients using the Revised ASTRO Criterion–"NADIR +2"

2007 ◽  
Vol 177 (4S) ◽  
pp. 126-126
Author(s):  
Matthew E. Nielsen ◽  
Danil V. Makarov ◽  
Elizabeth B. Humphreys ◽  
Leslie A. Mangold ◽  
Alan W. Partin ◽  
...  
Keyword(s):  
Biochemical Recurrence ◽  
Critical Analysis

Effectiveness of Programs for the Prevention of Child Sexual Abuse

2020 ◽  
Vol 25 (1) ◽  
pp. 1-15 ◽  
Author(s):  
Amaia Del Campo ◽  
Marisalva Fávero
Keyword(s):  
United States ◽  
Sexual Abuse ◽  
New Zealand ◽  
Critical Analysis ◽  
Prevention Programs ◽  
The United States ◽  
Sexual Abuse Prevention ◽  
Negative Effects ◽  
The United Kingdom ◽  
Methodological Considerations

Abstract. During the last decades, several studies have been conducted on the effectiveness of sexual abuse prevention programs implemented in different countries. In this article, we present a review of 70 studies (1981–2017) evaluating prevention programs, conducted mostly in the United States and Canada, although with a considerable presence also in other countries, such as New Zealand and the United Kingdom. The results of these studies, in general, are very promising and encourage us to continue this type of intervention, almost unanimously confirming its effectiveness. Prevention programs encourage children and adolescents to report the abuse experienced and they may help to reduce the trauma of sexual abuse if there are victims among the participants. We also found that some evaluations have not considered the possible negative effects of this type of programs in the event that they are applied inappropriately. Finally, we present some methodological considerations as critical analysis to this type of evaluations.

Sign in / Sign up

Export Citation Format

Share Document