Nitrate-dependent degradation of 17α-ethinylestradiol by acclimated activated sludge under anaerobic conditions

2009 ◽  
Vol 84 (12) ◽  
pp. 1841-1847 ◽  
Author(s):  
Qingling Zeng ◽  
Yongmei Li ◽  
Guowei Gu
RSC Advances ◽  
2015 ◽  
Vol 5 (33) ◽  
pp. 25699-25707 ◽  
Author(s):  
Bin Qiu ◽  
Xinzhu Xu ◽  
Yan Dang ◽  
Qiang Wang ◽  
Dezhi Sun ◽  
...  

Azo dye was completely decolorized and degraded to methane and ammonia by bacteria and archaea under anaerobic conditions.


2008 ◽  
Vol 57 (6) ◽  
pp. 915-919 ◽  
Author(s):  
L. Zhang ◽  
L. Mendoza ◽  
M. Marzorati ◽  
W. Verstraete

Hydrogen sulfide emission in sewers is associated with toxicity, corrosion, odor nuisance and a lot of costs. The possibility to inhibit sulfide generation by formaldehyde and its derivatives (paraformaldehyde and urea formaldehyde) has been evaluated under anaerobic conditions. The impact of formaldehyde on an activated sludge system and an appraisal of the economic aspects are also presented. The optimum dosage to inhibit sulfide generation in sewage was 12–19 mg L−1 formaldehyde. The dosages of 32 mg L−1 paraformaldehyde or 100 mg L−1 urea formaldehyde were not capable of inhibiting sulfide generation in sewage. The impact of 19 mg L−1 formaldehyde on activated sludge system was negligible in terms of COD removal, nitrification rate and oxygen uptake rate.


1982 ◽  
Vol 14 (1-2) ◽  
pp. 31-45 ◽  
Author(s):  
J L Barnard

This paper discusses the need for anaerobiases as a pre-requisite for phosphorus removal in activated sludge plants and the effect of nitrates on the anaerobic conditions. If the plant could be operated to avoid nitrification, biological phosphorus removal presents no problems. When nitrification is required, the nitrates must be reduced to a low level through internal denitrification. If sufficient carbon is available to ensure complete removal of the nitrates and anaerobic conditions in a specific zone in the plant, good phosphate removal can be ensured. Below COD : TKN ratios of 10 : 1 it is becoming more difficult to control the plant and special care should be taken to determine not only the quantity of organic carbon available as electron donors for removal of the nitrates but also the form in which it arrives at the plant.


2020 ◽  
Vol 2 (4) ◽  
Author(s):  
Dhan Lord B. Fortela ◽  
Wayne Sharp ◽  
Emmanuel Revellame ◽  
Andrei Chistoserdov ◽  
William Holmes ◽  
...  

2019 ◽  
Vol 79 (6) ◽  
pp. 1081-1091 ◽  
Author(s):  
V. F. Velho ◽  
G. Andreottola ◽  
P. Foladori ◽  
R. H. R. Costa

Abstract A full-scale anaerobic side-stream reactor (ASSR) for sludge reduction was monitored in terms of sludge production and compared with the previous conventional activated sludge configuration (CAS). A detailed solid mass balance was calculated on the whole full-scale plant to estimate the sludge reduction associated with the ASSR. The activity of the biomass, which undergoes alternation of aerobic and anaerobic conditions, was investigated by the respirometric test. The ASSR promoted a reduction of heterotrophic biomass activity and the substrate consumption rate in the activated sludge implemented with ASSR (AS + ASSR) was 36% smaller than in the CAS period. The solid mass balance indicated a sludge reduction of 28%. During the 270-day operation, the observed sludge yield passed from 0.438 kgTSS/kgCOD in the CAS to 0.315 in the AS + ASSR configuration. The solubilization of chemical oxygen demand (COD), NH4+-N and orthophosphate were verified under anaerobic conditions. The results suggest that the possible mechanisms of sludge reduction were the increase of the system sludge retention time (SRT) by ASSR addition, and the reduction in heterotrophic biomass activity added to the organic compounds' hydrolysis.


Sign in / Sign up

Export Citation Format

Share Document