Application of activated sludge and biofilm sequencing batch reactor technology to treat reject water from sludge dewatering systems: a comparison

2000 ◽  
Vol 41 (1) ◽  
pp. 115-122 ◽  
Author(s):  
E. Arnold ◽  
B. Böhm ◽  
P.A. Wilderer

Side stream reactors to treat reject water from sludge dewatering facilities may be considered to be small treatment plants embedded in large ones. Combination of main stream and side stream treatment provides a number of advantages. Of major importance is that tailored processes can be employed for the two waste streams very different in composition and concentration. Pilot scale experiments were conducted to study the applicability, and to compare the performance of two types of Sequencing Batch Reactor (SBR) systems, an activated sludge and a biofilm SBR. The reactors were operated to achieve nitrification only. Subsequently, the effluent of the reactors is fed into the anoxic zone of the main stream activated sludge plant to achieve denitrification. In general it can be stated that both, activated sludge and biofilm SBR systems are applicable for treating reject water of high ammonia loading. Nitrogen removal efficiencies of more than 90% could be obtained with both systems. If complete nitrification without denitrification is to be achieved, pH control is necessary. However, the amount of sodium hydroxide required for adjusting the pH during nitrification is significant. Foam development and accumulation caused major problems, especially during the early stage of start up. But the time proceeding, and by changing the type of polyelectrolyte used in the sludge dewatering process foam problems could be kept under control.

2012 ◽  
Vol 518-523 ◽  
pp. 569-574
Author(s):  
Qiong Wan ◽  
Lei Li ◽  
Dang Cong Peng

Enhancing nitrification from municipal wastewater by bioaugmentation was investigated in a pilot plant operated in A2/O process. Reject water was used to cultivate nitrifier in O/A process (side stream), and the exceed sludge in side stream was used to bioaugmentation. The experimental results showed that bioaugmentation was very effective for enhancing nitrification. After nitrifier bioaugmentation, the NH4+-N removal rate was improved more than 30% in main stream. And AUR and NUR of the activated sludge increased from 2.61 mgNH4+-N /(gMLSS•h) and 2.38 mgNO2--N/(gMLSS•h) to 5.32 mgNH4+-N /(gMLSS•h) and 3.81 mgNO2--N/(gMLSS•h), which was as 2.04 times and 1.60 times as those of before bioaugmentation in main stream respectively.


2018 ◽  
Vol 4 (4) ◽  
pp. 569-581 ◽  
Author(s):  
Renzun Zhao ◽  
Hong Zhao ◽  
Rich Dimassimo ◽  
Guoren Xu

IFAS process was coupled with SBR operation in a pilot-scale reactor to verify the feasibility and to evaluate the performance of IFAS-SBR. Significant nitrification improvement in the IFAS-SBR system was observed, which is attributed to both the introduction of attached-growth biomass on media carriers and the “seeding effect” by biofilm sloughing.


2006 ◽  
Vol 6 (6) ◽  
pp. 71-79 ◽  
Author(s):  
B.L. Hu ◽  
P. Zheng ◽  
Q. Mahmood ◽  
H.F. Qian ◽  
D.L. Wu

Anaerobic sequencing batch reactor (SBR) was started-up by inoculating the nitrifying activated sludge. After an operation of 72 d, the bioreactor reached at steady state with ammonia and nitrite removal percentages higher than 95%. During operation, the sludge granulated in the reactor. The morphology and internal structure of sludge granules changed conspicuously, the density increased while the color changed from khaki to red. The average granular diameter grew from 1.2 to 3.69 mm, and its settling velocity accelerated from 107.68 to 118.49 m/h. Sludge granulation improved the tolerance to hydraulic shock loading, and reduced sludge washout (TSS < 0.028 g/L). The dominant bacterial communities (filamentous and cocci) in nitrifying activated sludge were replaced by irregular shaped ANAMMOX bacterial species gradually. An increase of ANAMMOX rate was achieved with the increasing granular diameter. SBR is a useful reactor to cultivate ANAMMOX granular sludge, while granular ANAMMOX sludge thus developed can be used as seeding sludge in a pilot-scale or full scale wastewater treatment plant.


2009 ◽  
Vol 43 (3) ◽  
pp. 751-761 ◽  
Author(s):  
Bing-Jie Ni ◽  
Wen-Ming Xie ◽  
Shao-Gen Liu ◽  
Han-Qing Yu ◽  
Ying-Zhe Wang ◽  
...  

2004 ◽  
Vol 50 (10) ◽  
pp. 27-33 ◽  
Author(s):  
E. Lai ◽  
S. Senkpiel ◽  
D. Solley ◽  
J. Keller

The sequencing batch reactor (SBR) process concept was applied to achieve efficient ammonium removal via nitrite under both laboratory and pilot-scale conditions. Both sets of experimental results show that without pH control or carbon addition the nitritation process consistently converted approximately 50% of the ammonium from biosolids dewatering liquids to nitrite with hydraulic retention times (HRT) as short as 10 h. The results from the pilot-scale study also indicate that the selective oxidation of ammonium to nitrite is a reliable process as the accumulation of nitrate was never an issue during a 330-day trial. The SBR process concept was extended to achieve complete nitrogen removal through nitritation and denitritation in the laboratory scale. The experimental results indicate that a total reduction of 96-98% of the ammonium nitrogen from biosolids dewatering liquids (influent concentration typically 1,200 g m-3 ) was achieved with a short HRT of 1.1 d and a removal rate of 1.05 kgNm-3d-1. This process concept was tested at pilot scale where the nitritation process could be started up without temperature control in a short period of time. Nitrogen removal rates up to 1.2 kgNm-3d-1 at an HRT of 0.88 d have been obtained. COD to nitrogen ratios required in the pilot plant were consistently in the range 1.6-1.9 kgCOD kg-1N removed.


1998 ◽  
Vol 37 (4-5) ◽  
pp. 95-98 ◽  
Author(s):  
Nancy G. Love ◽  
Mary E. Rust ◽  
Kathy C. Terlesky

An anaerobic enrichment culture was developed from an anoxic/anaerobic/aerobic activated sludge sequencing batch reactor using methyl ethyl ketoxime (MEKO), a potent nitrification inhibitor, as the sole carbon and energy source in the absence of molecular oxygen and nitrate. The enrichment culture was gradually fed decreasing amounts of biogenic organic compounds and increasing concentrations of MEKO over 23 days until the cultures metabolized the oxime as the sole carbon source; the cultures were maintained for an additional 41 days on MEKO alone. Turbidity stabilized at approximately 100 mg/l total suspended solids. Growth on selective media plates confirmed that the microorganisms were utilizing the MEKO as the sole carbon and energy source. The time frame required for growth indicated that the kinetics for MEKO degradation are slow. A batch test indicated that dissolved organic carbon decreased at a rate comparable to MEKO consumption, while sulfate was not consumed. The nature of the electron acceptor in anaerobic MEKO metabolism is unclear, but it is hypothesized that the MEKO is hydrolyzed intracellularly to form methyl ethyl ketone and hydroxylamine which serve as electron donor and electron acceptor, respectively.


2009 ◽  
Vol 59 (3) ◽  
pp. 573-582 ◽  
Author(s):  
Xiao-ming Li ◽  
Dong-bo Wang ◽  
Qi Yang ◽  
Wei Zheng ◽  
Jian-bin Cao ◽  
...  

It was occasionally found that a significant nitrogen loss in solution under neutral pH value in a sequencing batch reactor with a single-stage oxic process using synthetic wastewater, and then further studies were to verify the phenomenon of nitrogen loss and to investigate the pathway of nitrogen removal. The result showed that good performance of nitrogen removal was obtained in system. 0–7.28 mg L−1 ammonia, 0.08–0.38 mg L−1 nitrite and 0.94–2.12 mg L−1 nitrate were determined in effluent, respectively, when 29.85–35.65 mg L−1 ammonia was feeding as the sole nitrogen source in influent. Furthermore, a substantial nitrogen loss in solution (95% of nitrogen influent) coupled with a little gaseous nitrogen increase in off-gas (7% of nitrogen influent) was determined during a typical aerobic phase. In addition, about 322 mg nitrogen accumulation (84% of nitrogen influent) was detected in activated sludge. Based on nitrogen mass balance calculation, the unaccounted nitrogen fraction and the ratio of nitrogen accumulation in sludge/nitrogen loss in solution were 14.6 mg (3.7% of nitrogen influent) and 0.89, respectively. The facts indicated that the essential pathway of nitrogen loss in solution in this study was excess nitrogen accumulation in activated sludge.


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