scholarly journals STUDY ON GRANULATION OF ACTIVATED SLUDGE USING SEQUENCING BATCH AIRLIFT REACTOR FOR COD AND AMMONIA REMOVAL

2009 ◽  
Vol 12 (2) ◽  
pp. 39-50
Author(s):  
Luc Trong Nguyen ◽  
Dan Phuoc Nguyen ◽  
Nam Tay Tran
Keyword(s):  
Carbon Source ◽  
Settling Velocity ◽  
Hydraulic Retention Time ◽  
Ammonia Removal ◽  
Airlift Reactor ◽  
Synthetic Wastewater ◽  
Aerobic Granules ◽  
Organic Loading ◽  
Loading Rates ◽  
Shell Powder

Synthetic wastewater with glucose as carbon source was used for cultivation of aerobic granules in sequencing batch airlift reactor (SBAR). Grinded shell powder with diatmeter of 150-200 um used as carrier. SBAR was run at hydraulic retention time (HRT) 5.1 hours, airflow of 4 liters/m and airlift velocity of 4.2 cm/s. The experiment was run at two organic loading rates (OLRs). They were 2.6 and 5.2 kg COD/m°.day, corresponding to influent COD and N-ammonia of 600; 1200 mg/l and 26; 60 mg/l, respectively. After 61 days of running, aerobic granules with size of 1,0-1,2 mm are formed. The size of granules increased to 5 mm at 80th day. Aerobic granules had settling velocity of 36-56 m/h, SVI of 11,4-44.2 ml/g. COD and N-ammonia removal of SBAR were greater than 96% and 75-90%, respectively. It was found that nitrification and denitrification occurred simultaneously in granules.' The COD and N-animonia of SBAR decreased to 70% and 51%, respectively when filamentous sludge bulking and viscous bulking appeared simultaneously.

scholarly journals Performance of Modified Anaerobic Hybrid Baffled (MAHB) bioreactor treating recycled paper mill effluent: Effects of organic loading rates

2021 ◽  
Vol 6 (1) ◽  
pp. 15-18
Author(s):  
Siti Roshayu Hassan ◽  
Irvan Dahlan
Keyword(s):  
Hydraulic Retention Time ◽  
Biogas Production ◽  
Oxygen Demand ◽  
Paper Mill ◽  
Organic Loading ◽  
Recycled Paper ◽  
Paper Mill Effluent ◽  
Loading Rates ◽  
Bioreactor System ◽  
Maximum Removal

The performance of modified anaerobic hybrid baffled (MAHB) bioreactor treating recycled paper mill effluent (RPME) was investigated at various organic loading rates (OLR) of 1, 2, 3 and 4 g COD/ L.day. The bioreactor was operated continuously at constant hydraulic retention time (HRT) of a day without effluent recycled and chemicals adjustment/addition. Throughout 70 days of operation, a maximum removal efficiency up to 97% of chemical oxygen demand (COD) and 98% of volatile fatty acid, biogas production of 12.51 L/day equivalent to methane (CH4) yield of 0.108L CH4/ g COD and a stable pH system between 6.6 to 7.2 were achieved. Additionally, alkalinity of the bioreactor system shows a stable profile that indicates the whole system was well buffered with a quit high degradation of volatile solid (VS) up to 18%. These results indicated that MAHB bioreactor has been successfully treated RPME at various OLR.

Assessment of classical surface organic loading design equations based on the actual performance of primary and secondary facultative ponds

2010 ◽  
Vol 61 (4) ◽  
pp. 971-977 ◽  
Author(s):  
Sílvia C. Oliveira ◽  
Marcos von Sperling
Keyword(s):  
Performance Evaluation ◽  
Hydraulic Retention Time ◽  
Operating Conditions ◽  
Empirical Equations ◽  
Organic Loading ◽  
Actual Performance ◽  
Loading Rates ◽  
Limit Value ◽  
Classical Design ◽  
Operational Aspects

This article presents results from a performance evaluation of 73 full-scale primary facultative ponds and 37 secondary facultative ponds in Brazil. The data were used to test the applicability of some classical design equations for recommended surface BOD loading rates. The empirical equations proposed by Mara in 1976 and 1987 and the equation developed by McGarry and Pescod in 1970 were evaluated. The loading and hydraulic operating conditions were also evaluated to support the analysis of the influence of the parameters surface BOD loading (Ls) and hydraulic retention time (HRT) on the performance of the ponds. The results showed that the design equations proposed by Mara showed good applicability for primary facultative ponds, representing good indicators of the limit value of loading rates to be applied on the units. But the secondary facultative ponds showed good and poor performances for all loading rates and the best ponds, in general, were not those which followed the design equations recommendation. Finally, the influence of the actual loading conditions on the ponds performance was very small and scattered, indicating that other unquantified design and operational aspects were playing an important role.

Enhanced removal of chemical oxygen demand, nitrogen and phosphorus using the ameliorative anoxic/anaerobic/oxic process and micro-electrolysis

2012 ◽  
Vol 66 (4) ◽  
pp. 850-857 ◽  
Author(s):  
K. Q. Bao ◽  
J. Q. Gao ◽  
Z. B. Wang ◽  
R. Q. Zhang ◽  
Z. Y. Zhang ◽  
...  
Keyword(s):  
Chemical Oxygen Demand ◽  
Hydraulic Retention Time ◽  
Loading Rate ◽  
Oxygen Demand ◽  
Synthetic Wastewater ◽  
Organic Loading Rate ◽  
Organic Loading ◽  
Nitrogen And Phosphorus ◽  
Operational Conditions ◽  
Removal Efficiencies

Synthetic wastewater was treated using a novel system integrating the reversed anoxic/anaerobic/oxic (RAAO) process, a micro-electrolysis (ME) bed and complex biological media. The system showed superior chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) removal rates. Performance of the system was optimised by considering the influences of three major controlling factors, namely, hydraulic retention time (HRT), organic loading rate (OLR) and mixed liquor recirculation (MLR). TP removal efficiencies were 69, 87, 87 and 83% under the HRTs of 4, 8, 12 and 16 h. In contrast, HRT had negligible effects on the COD and TN removal efficiencies. COD, TN and TP removal efficiencies from synthetic wastewater were 95, 63 and 87%, respectively, at an OLR of 1.9 g/(L·d). The concentrations of COD, TN and TP in the effluent were less than 50, 15 and 1 mg/L, respectively, at the controlled MLR range of 75–100%. In this system, organics, TN and TP were primarily removed from anoxic tank regardless of the operational conditions.

Functional consortium from aerobic granules under high organic loading rates

2009 ◽  
Vol 100 (14) ◽  
pp. 3465-3470 ◽  
Author(s):  
Sunil S. Adav ◽  
Duu-Jong Lee ◽  
Juin-Yih Lai
Keyword(s):  
Aerobic Granules ◽  
Organic Loading ◽  
Loading Rates

Biological aerated filtration of municipal wastewater using a low-cost filtration media

2007 ◽  
Vol 55 (7) ◽  
pp. 255-262 ◽  
Author(s):  
S. González-Martínez ◽  
T. Millán ◽  
O. González-Barceló
Keyword(s):  
Municipal Wastewater ◽  
Low Cost ◽  
Ammonia Removal ◽  
Organic Load ◽  
Organic Loading ◽  
Removal Rates ◽  
Loading Rates ◽  
Different Depths ◽  
The Mean ◽  
Kjeldahl Nitrogen

The main objective of this research was to demonstrate that selected natural lava stones can be successfully used for low-cost aerobic biofiltration of municipal wastewater. To demonstrate the procedure a pilot filter was built using 6 mm lava stones as support material. The filter depth was 3.0 m. Provided with sampling ports at different depths analysis of the wastewater could be made for COD, TSS, ammonia and nitrates nitrogen, pH, temperature and Kjeldahl nitrogen. Backwashing was performed every 72 hours. Total and dissolved COD and TSS behaved similarly with the organic load: The highest removal rates were observed with the lowest organic load of 0.8 kgCOD/m3 d. These removal rates decreased to a minimum value at organic loading rates of 1.5 kgCOD/m3 d and then remained without noticeable changes to the highest value of 3.5 kgCOD/m3 d. The highest total and dissolved COD removal values were 81 and 84%, respectively. For TSS the best removal value was 95%. Up to 75% ammonia removal was achieved at the lowest organic load of 0.8 kgCOD/m3 d. Ammonia removal decreased to 36% with a higher organic load of 1.6 kgCOD/m3 d. The Mean Cellular Retention (MCRT) time varied from 1 to 6 days with an average of 3.2 days. This fact proves that the MCRT depends on the backwashing frequency more than of any other factor involved. The bed volume decreased in about 5% after 300 days of operation. Microscopic observations showed that the small stones were rounder after 300 days and that the volume losses were caused when the edges of the stones were cut by the abrasion caused by backwashing.

scholarly journals Improved hydrogen production from pharmaceutical intermediate wastewater in an anaerobic maifanite-immobilized sludge reactor

RSC Advances ◽  
2021 ◽  
Vol 11 (53) ◽  
pp. 33714-33722
Author(s):  
Ruina Liu ◽  
Youwei Lin ◽  
Xiaodong Ye ◽  
Jinzhao Hu ◽  
Gongdi Xu ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Retention Time ◽  
Hydraulic Retention Time ◽  
Organic Loading ◽  
Loading Rates

An anaerobic maifanite-immobilized sludge reactor was used to investigate continuous hydrogen production for treatment of pharmaceutical intermediate wastewater at different organic loading rates according to changes in the hydraulic retention time.

Biological Phosphorus Removal Using a Biofilm Membrane Reactor: Operation at High Organic Loading Rates

1999 ◽  
Vol 40 (4-5) ◽  
pp. 321-329 ◽  
Author(s):  
Pedro A. Castillo ◽  
Simón González-Martínez ◽  
Iñaki Tejero
Keyword(s):  
Phosphorus Removal ◽  
Membrane Reactor ◽  
Synthetic Wastewater ◽  
Organic Load ◽  
Biological Phosphorus Removal ◽  
Organic Loading ◽  
Removal Rates ◽  
Loading Rates ◽  
Biological Phosphorus ◽  
P Removal

This research describes Biological Phosphorus Removal at Organic Loading Rates from 5 to 30 g COD/m2·d using a laboratory scale Sequencing Batch Biofilm Membrane Reactor. The reactor was fed with synthetic wastewater based on sodium acetate with a COD:N:P ratio of 20:5:1. An average PO4-P removal of 72% was observed when the organic load was kept under 15 gCOD/m2·d. Maximum PO4-P removal of 85% was associated with a consumption rate of 700 mgPO4-P/m2·d. Increasing with the organic load, the PO4-P released during the anaerobic phase averages 40% over the influent concentration, showing a maximum value of 107%. Throughout the experiments, overall COD removal rates were above 90%, and the COD uptake during the anaerobic phase ranged between 60 and 80% for organic loading rates under 15 gCOD/m2·d. Simultaneous nitrification and dentrification took place during the transition from aerobic to anaerobic conditions at the beginning of every cycle. Average transformation rates between 0.6 to 2.0 gNH4-N/m2·d and 0.3 to 1.2 gNO3-N/m2·d were observed for organic loading rates under 15 gCOD/m2·d, corresponding to average NH4-N removal rates between 50 and 70%. Average effluent NO3-N ranged between 1.5 and 10.6 mg/l. Phosphorus contents of the biofilm based on dry mass ranged between 4.2 and 5.2%.

Another carbon source for BNR system

1996 ◽  
Vol 34 (1-2) ◽  
pp. 363-369 ◽  
Author(s):  
E. Choi ◽  
H. S. Lee ◽  
J. W. Lee ◽  
S. W. Oa
Keyword(s):  
Carbon Source ◽  
Activated Sludge ◽  
Phosphorus Removal ◽  
Organic Loading ◽  
Nitrogen And Phosphorus ◽  
Nitrogen And Phosphorus Removal ◽  
Loading Rates ◽  
Study Results ◽  
Removal Efficiencies ◽  
Low Strength

It has been known wastewater with low COD/TKN ratio produces higher effluent NO3-N and adversely affects poly P microbes returning it to an anaerobic stage in BNR systems. Nightsoil applicability to return activated sludge line to minimize NO3-N effect to poly P microbes in anaerobic stage was examined with laboratory BNR systems operated at 20°C. The study results indicated nightsoil application could improve nitrogen and phosphorus removal efficiencies both with low strength settled municipal and piggery wastes presenting low COD/TKN ratios of 6 and 2.2, respectively. Even organic loading rates increased to 20 to 60% due to nightsoil application, the effluent COD increased only 10 to 20%. This would suggest nightsoil can be used as another carbon source and nightsoil application to return activated sludge line can be another alternative modification to improve BNR systems.

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