scholarly journals Monitoring and control of a partially packed biological aerated filter (BAF) reactor for improving nitrogen removal efficiency

2011 ◽  
Vol 1 (3) ◽  
pp. 160-171 ◽  
Author(s):  
Pramanik Biplob ◽  
Suja Fatihah ◽  
Zain Shahrom ◽  
Elshafie Ahmed

This paper examines on-off systems and automatic monitoring and control of a biological aerated filter to identify the end point of nitrification and denitrification processes, and chemical oxygen demand (COD), ammonia-nitrogen removal (NH3-N) and aeration savings. Oxidation-reduction potential (ORP), pH and dissolved oxygen (DO) were measured on-line and chemical parameters were measured in the wastewater. The ‘nitrate knee’ in the ORP profile was characterised by a breakpoint at average 160 min, representing the complete removal of NO3-N, i.e. the end of the denitrification period, as well as the end of the nitrification period was clearly shown in the pH profile (ammonia valley) at average 210 min for all C/N ratios. The NH3-N removal efficiencies were 92.30, 97.57 and 98.02% whilst the COD removals of 95.06, 96.38 and 97.56% were achieved for the C/N ratios of 10, 4 and 1 respectively. Therefore, the on-off control was operated at average 230 min for aeration time and 130 min for the anoxic period. Thus significant improvements can be achieved with respect to the continuous aeration strategy, and average operational costs reduced by 36.11%. The study showed that an on-off controller can easily be implemented in wastewater process-control, and monitoring systems improve effluent quality and reduce energy consumption.

2016 ◽  
Vol 73 (8) ◽  
pp. 2031-2038 ◽  
Author(s):  
L. Y. Fu ◽  
C. Y. Wu ◽  
Y. X. Zhou ◽  
J. E. Zuo ◽  
Y. Ding

In this study, petrochemical secondary effluent was treated by a 55 cm diameter pilot-scale biological aerated filter (BAF) with a media depth of 220 cm. Volcanic rock grains were filled as the BAF media. Median removal efficiency of chemical oxygen demand (COD) and ammonia nitrogen (NH3-N) was 29.35 and 57.98%, respectively. Moreover, the removal profile of the COD, NH3-N, total nitrogen and total organic carbon demonstrated that the filter height of 140 cm made up to 90% of the total removal efficiency of the final effluent. By gas chromatography–mass spectrometry, removal efficiencies of 2-chloromethyl-1,3-dioxolane, and benzonitrile, indene and naphthalene were obtained, ranging from 30.12 to 63.01%. The biomass and microbial activity of the microorganisms on the filter media were in general reduced with increasing filter height, which is consistent with the removal profile of the contaminants. The detected genera Defluviicoccus, Betaproteobacteria_unclassified and the Blastocatella constituted 1.86–6.75% of the identified gene, enhancing the COD and nitrogen removal in BAF for treating petrochemical secondary effluent.


2011 ◽  
Vol 1 (1) ◽  
pp. 27-35 ◽  
Author(s):  
Pramanik Biplob ◽  
Suja Fatihah ◽  
Zain Shahrom ◽  
ElShafie Ahmed

An upflow, partially packed biological aerated filter (BAF) reactor was used to remove nitrogen in the form of ammonia ions by a nitrification process that involves physical, chemical and biological phenomena governed by a variety of parameters such as dissolved oxygen concentration, pH and alkalinity. Dissolved oxygen (DO) and pH were shown to have effects on the nitrification process in this study. Three C:N ratios i.e., 10, 4 and 1 were compared during this study by varying the nitrogen loading while the carbon loading was kept constant at 0.405 ± 0.015 kg chemical oxygen demand m−3 d−1. The removal efficiencies of ammonia linearly increase with a rise of the initial concentration of ammonia-nitrogen. The results of the 115 days' operation of the BAF system showed that its overall NH3-N performance was good, where a removal efficiency of 87.0 ± 2.9%, 89.2 ± 1.38% and 91.1 ± 0.7% and COD removal of 87.6 ± 2.9%, 86.4 ± 2.1% and 89.5 ± 2.6% were achieved for the C:N ratios of 10, 4 and 1, respectively on average, over 6 h hydraulic retention time (HRT). No clogging occurred throughout the period although backwashing was eliminated. It was concluded that the BAF system proposed in this study removed nitrogen by the nitrification process extremely well.


2019 ◽  
Vol 25 (4) ◽  
pp. 554-560 ◽  
Author(s):  
Jin-Su Kim ◽  
Ji-Young Lee ◽  
Seung-Kyu Choi ◽  
Qian Zhu ◽  
Sang-Ill Lee

This study focuses on nitrification through a biological aerated filter (BAF) that is filled with a zeolite medium at low concentrations of ammonia. The zeolite medium consists of natural zeolite powder. The BAF is operated under two types of media, which are a ball-type zeolite medium and expanded poly propylene (EPP) medium. Nitrification occurred in the zeolite BAF (ZBAF) when the influent concentration of ammonia nitrogen was 3 mg L-1, but the BAF that was filled with an EPP medium did not experience nitrification. The ammonia nitrogen removal efficiency of ZBAF was 63.38% and the average nitrate nitrogen concentration was 1.746 mg/L. The ZBAF was tested again after a comparison experiment to treat pond water, and municipal wastewater mixed pond water. The ZBAF showed remarkable ammonia-nitrogen treatment at low concentration and low temperature. During this period, the average ammonia nitrogen removal efficiency was 64.56%. Especially, when water temperature decreased to 4.7℃, ammonia nitrogen removal efficiency remained 79%. On the other hand, the chemical-oxygen demand (COD) and phosphorus-removal trends were different. The COD and phosphorus did not show as efficient treatment as the ammonia-nitrogen treatment.


2011 ◽  
Vol 183-185 ◽  
pp. 720-724 ◽  
Author(s):  
Ping Li ◽  
Li Long Yan ◽  
Fang Ma

Biological Aerated Filter has the drawback of severe plug under low temperature, and frequent back-washing would cause the bad performance of ammonia removal. To solve these shortcomings, partial backwashing experiment was carried out to test its amelioration effect on Biological Aerated Filter. The result showed that performing backwashing at the 40 cm of filter had strong protective effect on nitrifying bacteria, the ammonia removal could be improved gradually with the highest removal rate of 71.71%. Partial backwashing affected less on ammonia removal and the removal efficiency could be restored to the previous level after the backwashing completed for 2.5 h.


2013 ◽  
Vol 361-363 ◽  
pp. 644-649
Author(s):  
Guo Min Tang ◽  
Peng Cao ◽  
Shuang Wang ◽  
Yun Chen

Wastewater from hair products was the industrial wastewater typically hard to treat with high concentration ammonia nitrogen (NH4+-N) and the low Carbon to Nitrogen (C/N) ratio. In this study ,a pilot-scale study was conducted on Biological Aerated Filter ( BAF) to deeply remove NH4+-N in wastewater from hair products, which aimed to provide technology support for hair products enterprises.The experiments showed that the optimal conditions of BAF was as following: the ratio of air to water was 19:1, the ammonia nitrogen volumetric load was 0.22 kgm3d-1, in this situation the removal efficiency of Chemical Oxygen Demand (CODcr) and NH4+-N were respectively from 25.0% to 32.5% and from 90.6% to 92.5%, the NH4+-N concentrations and CODcr in effluent were always under 12 mg/L and 100 mg/L respectively, which meet fully first class discharge standard requirement of Integrated wastewater discharge standard in china (GB8978-1996)(IWDSC). Moreover the experiment demonstrated that BAF returned to normal at the moment of 2.5 hours after the end of backwashing.


2013 ◽  
Vol 316-317 ◽  
pp. 241-244 ◽  
Author(s):  
Xu Jie Lu

A biologically aerated filter (BAF) is a novel, flexible and effective bioreactor that provides a small footprint process option at various stages of wastewater treatment. Double layers of activated carbon and ceramsite were applied in the biological aerated filter reactor. An experiment was conducted under laboratory conditions to investigate the treatment efficiencies at different air/liquid ratios. The experimental results obtained showed that air/liquid ratio had a greater effect on NH4+–N removal than COD removal. More than 80% ammonia nitrogen was removed at 2 of air/liquid ratio. However, less than 50% COD was removed at 2 of air/liquid ratio.


2013 ◽  
Vol 777 ◽  
pp. 117-121
Author(s):  
Dong Wang ◽  
Li Ping Qiu ◽  
Chun Hui Guo ◽  
Qiang Liu

The performance of three BAFs with zeolite, activated carbon and anthracite media for the treatment of polluted Huaihe raw water were investigated. All three BAFs performed promising permanganate index (CODMn) and ammonia nitrogen (NH4+-N) removal efficiency as well as the turbidity removal was over 60%. Moreover, the CODMn and NH4+-N removal in the three BAFs were affacted by the characteristics of filter media. Activated carbon and anthracite had better CODMn removal than zeolite. Zeolite had the best NH4+-N removal, followed by activated carbon, anthracite was the worst.


Water ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 21
Author(s):  
Ilaria Piccoli ◽  
Giuseppe Virga ◽  
Carmelo Maucieri ◽  
Maurizio Borin

Constructed wetlands (CWs) represent a green technology for digestate liquid fraction (DLF) treatment. However, previous research has warned about their performance when treating wastewater with high suspended solid and organic loads. In addition, the high NH4-N concentration typical of this wastewater can compromise vegetation establishment and activity. In view of this, a digestate pretreatment is needed. This study aimed to test the performance of filters filled with recovery materials, such as brick and refractory material, for DLF pretreatment. The effect on DLF physical (electrical conductivity, pH, dissolved oxygen, and temperature) and chemical (total nitrogen, ammonia–nitrogen, nitrate–nitrogen, total phosphorus, soluble phosphorus, and chemical oxygen demand) characteristics was monitored during eight weekly cycles. The effect of filtration on total nitrogen and ammonia–nitrogen removal began after about one month of loading, suggesting that an activation period is necessary for bacteria. For effective N removal, the presence of multiple digestate recirculations per day through the filters appears mandatory to guarantee the alternation of nitrification and denitrification conditions. For P removal, filling material particle size appeared to be more important than its composition. Unclear performances were observed considering chemical oxygen demand. Further studies on filling media and microbial community interactions, and the long-term efficiency of filters, are desirable.


2001 ◽  
Vol 43 (1) ◽  
pp. 269-276 ◽  
Author(s):  
N. Puznava ◽  
M. Payraudeau ◽  
D. Thornberg

The aim of this article is to present a new biological aerated filter (BAF) for nitrogen removal based on simultaneous nitrification and denitrification. Contrary to the systems which integrate both an aerated and a non-aerated zone to allow complete nitrogen removal in one compact or two different units (pre-denitrification and nitrification), this upflow BAF system is based on the principle of simultaneous nitrification and denitrification since the filter is completely aerated. The denitrification process is possible due to the diffusion effect which dominates biofilm processes. The real time aeration control allows us to maintain a low dissolved oxygen value (0.5 to 3 mg O2/l). In this case, the biofilm will not be fully (or less) penetrated with oxygen and denitrification will be carried out in a large part of the biofilm. Therefore, nitrification and denitrification is running simultaneously in different depths of the biofilm. By using 50% less air this BAF gave the same results (less than 20mg TN/l) on pilot plant as a classical nitrification and denitrification BAF (Toettrup et al., 1994). Less recirculation was necessary to achieve the same denitrification.


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