scholarly journals Effect of carrier fill ratio on biofilm properties and performance of a hybrid fixed-film bioreactor treating coal gasification wastewater for the removal of COD, phenols and ammonia-nitrogen

2016 ◽  
Vol 73 (10) ◽  
pp. 2461-2467 ◽  
Author(s):  
E. Rava ◽  
E. Chirwa
Keyword(s):  
Coal Gasification ◽  
Heterotrophic Bacteria ◽  
Oxygen Demand ◽  
High Strength ◽  
Ammonia Nitrogen ◽  
Nitrifying Bacteria ◽  
Fixed Film ◽  
Coal Gasification Wastewater ◽  
And Performance ◽  
Fixed Film Bioreactor

The purpose of this study was to determine the effect different biofilm carrier filling ratios would have on biofilm morphology and activity and bacterial diversity in a hybrid fixed-film bioreactor treating high strength coal gasification wastewater (CGWW) for the removal of chemical oxygen demand (COD), phenols and ammonia-nitrogen. Results showed that a carrier fill of 70% formed a ‘compact’ biofilm, a 50% fill formed a ‘rippling’ biofilm and a 30% fill formed a ‘porous’ biofilm. The highest microbial activity was obtained with a 50% carrier fill supporting a relatively thin biofilm. The highest level of biofilm bound metals were aluminium, silicon, calcium and iron in the ‘compact’ biofilm; nitrogen, magnesium, chloride, sodium and potassium in the ‘rippling’ biofilm, and copper in the ‘porous’ biofilm. The bioreactor improved the quality of the CGWW by removing 49% and 78% of the COD and phenols, respectively. However, no significant amount of ammonia-nitrogen was removed since nitrification did not take place due to heterotrophic bacteria out-competing autotrophic nitrifying bacteria in the biofilm. The dominant heterotrophic genera identified for all three carrier filling ratios were Thauera, Pseudaminobacter, Pseudomonas and Diaphorobacter.

Removal of nitrogen from coal gasification wastewater by nitrosofication and denitrosofication

1998 ◽  
Vol 38 (1) ◽  
pp. 39-46 ◽  
Author(s):  
Junxin Liu ◽  
Weiguang Li ◽  
Xiuheng Wang ◽  
Hongyuan Liu ◽  
Baozhen Wang
Keyword(s):  
Nitrogen Removal ◽  
Coal Gasification ◽  
Oxygen Demand ◽  
Test Results ◽  
New Process ◽  
Scale Test ◽  
Coal Gasification Wastewater ◽  
Total Nitrogen Removal ◽  
Biological Nitrogen ◽  
Bench Scale Test

In this paper, a study of a new process with nitrosofication and denitrosofication for nitrogen removal from coal gasification wastewater is reported. In the process, fibrous carriers were packed in an anoxic tank and an aerobic tank for the attached growth of the denitrifying bacteria and Nitrobacter respectively, and the suspended growth activated sludge was used in an aerobic tank for the growth of Nitrosomonas. A bench scale test has been carried out on the process, and the test results showed that using the process, 25% of the oxygen demand and 40% of the carbon source demand can be saved, and the efficiency of total nitrogen removal can increase over 10% as compared with a traditional process for biological nitrogen removal.

High-strength nitrogen removal of opto-electronic industrial wastewater in membrane bioreactor - a pilot study

2003 ◽  
Vol 48 (1) ◽  
pp. 191-198 ◽  
Author(s):  
T.K. Chen ◽  
C.H. Ni ◽  
J.N. Chen ◽  
J. Lin
Keyword(s):  
Wastewater Treatment ◽  
Industrial Wastewater ◽  
Organic Nitrogen ◽  
Membrane Bioreactor ◽  
High Strength ◽  
Experimental Period ◽  
Ammonia Nitrogen ◽  
Nitrifying Bacteria ◽  
Biological Degradation ◽  
The Past

The membrane bioreactor (MBR) system has become more and more attractive in the field of wastewater treatment. It is particularly attractive in situations where long solids retention times are required, such as nitrifying bacteria, and physical retention critical to achieving more efficiency for biological degradation of pollutant. Although it is a new technology, the MBR process has been applied for industrial wastewater treatment for only the past decade. The opto-electronic industry, developed very fast over the past decade in the world, is high technology manufacturing. The treatment of the opto-electronic industrial wastewater containing a significant quantity of organic nitrogen compounds with a ratio over 95% in organic nitrogen (Org-N) to total nitrogen (T-N) is very difficult to meet the discharge limits. This research is mainly to discuss the treatment capacity of high-strength organic nitrogen wastewater, and to investigate the capabilities of the MBR process. A 5 m3/day capacity of MBR pilot plant consisted of anoxic, aerobic and membrane bioreactor was installed for evaluation. The operation was continued for 150 days. Over the whole experimental period, a satisfactory organic removal performance was achieved. The COD could be removed with an average of over 94.5%. For TOC and BOD5 items, the average removal efficiencies were 96.3 and 97.6%, respectively. The nitrification and denitrification was also successfully achieved. Furthermore, the effluent did not contain any suspended solids. Only a small concentration of ammonia nitrogen was found in the effluent. The stable effluent quality and satisfactory removal performance mentioned above were ensured by the efficient interception performance of the membrane device incorporated within the biological reactor. The MBR system shows promise as a means of treating very high organic nitrogen wastewater without dilution. The effluent of TKN, NOx-N and COD can fall below 20 mg/L, 30 mg/L and 50 mg/L.

scholarly journals Simultaneous nitrification and denitrification (SND) bioaugmentation with Pseudomonas sp. HJ3 inoculated for enhancing phenol and nitrogen removal in coal gasification wastewater

2019 ◽  
Vol 80 (8) ◽  
pp. 1512-1523
Author(s):  
Weiwei Ma ◽  
Yuxing Han ◽  
Wencheng Ma ◽  
Hongjun Han ◽  
Chunyan Xu ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Nitrogen Removal ◽  
Coal Gasification ◽  
Oxygen Demand ◽  
Community Analysis ◽  
Microbial Community Analysis ◽  
Simultaneous Nitrification And Denitrification ◽  
Pseudomonas Sp ◽  
Coal Gasification Wastewater ◽  
Nitrification And Denitrification

Abstract A simultaneous nitrification and denitrification (SND) bioaugmention system with Pseudomonas sp. HJ3 inoculated was established to explore the potential of simultaneous phenol and nitrogen removal in coal gasification wastewater (CGW). When the concentration of influent chemical oxygen demand (COD) and total phenols (TPh) was 1,765.94 ± 27.43 mg/L and 289.55 ± 10.32 mg/L, the average removal efficiency of COD and TPh at the stable operating stage reached 64.07% ± 0.76% and 74.91% ± 0.33%, respectively. Meanwhile, the average removal efficiency of NH4+-N and total nitrogen (TN) reached 67.96% ± 0.17% and 57.95% ± 0.12%, respectively. The maximum SND efficiency reached 83.51%. Furthermore, SND bioaugmentation performed with good nitrification tolerance of phenol shock load and significantly reduced toxic inhibition of organisms. Additionally, the microbial community analysis indicated that Pseudomonas sp. HJ3 was the predominant bacterium in the SND bioaugmentation system. Moreover, the indigenous nitrogen removal bacteria such as Thauera, Acidovorax and Stenotrophomonas were enriched, which further enhanced the nitrogen removal in the SND bioaugmentation system. The results demonstrated the promising application of SND bioaugmentation for enhancing simultaneous phenol and nitrogen removal in CGW treatment.

scholarly journals Performance of up flow anaerobic sludge fixed film bioreactor for the treatment of high organic load and biogas production of cheese whey wastewater

2015 ◽  
Vol 21 (2) ◽  
pp. 229-237 ◽  
Author(s):  
Nazila Tehrani ◽  
Ghasem Najafpour ◽  
Mostafa Rahimnejad ◽  
Hossein Attar
Keyword(s):  
Wastewater Treatment ◽  
Biogas Production ◽  
Oxygen Demand ◽  
Pilot Scale ◽  
Cod Removal ◽  
Organic Load ◽  
Anaerobic Sludge ◽  
Operation Temperature ◽  
Fixed Film ◽  
Fixed Film Bioreactor

Among various wastewater treatment technologies, biological wastewater treatment appears to be the most promising method. A pilot scale of hybrid anaerobic bioreactor was fabricated and used for the whey wastewater treatment. The top and bottom of the hybrid bioreactor known as up flow anaerobic sludge fixed film (UASFF); was a combination of up flow anaerobic sludge blanket (UASB) and up flow anaerobic fixed film reactor (UAFF), respectively. The effects of operating parameters such as temperature and hydraulic retention time (HRT) on chemical oxygen demand (COD) removal and biogas production in the hybrid bioreactor were investigated. Treatability of the samples at various HRTs of 12, 24, 36 and 48 hours was evaluated in the fabricated bioreactor. The desired conditions for COD removal such as HRT of 48 hours and operation temperature of 40 ?C were obtained. The maximum COD removal and biogas production were 80% and 2.40 (L/d), respectively. Kinetic models of Riccati, Monod and Verhalst were also evaluated for the living microorganisms in the treatment process. Among the above models, Riccati model was the best growth model fitted with the experimental data with R2 of about 0.99.

Nitrogen and organics removal from industrial wastewater using natural zeolite media

2000 ◽  
Vol 42 (5-6) ◽  
pp. 127-134 ◽  
Author(s):  
Y.-C. Chung ◽  
D.-H. Son ◽  
D.-H. Ahn
Keyword(s):  
Natural Zeolite ◽  
Industrial Wastewater ◽  
High Strength ◽  
Ammonia Nitrogen ◽  
Ammonium Ion ◽  
Nitrifying Bacteria ◽  
Ion Removal ◽  
Biological Removal ◽  
Organics Removal ◽  
Raw Wastewater

Biological removal of nitrogen from industrial wastewater was investigated by a novel O/A (oxic/anoxic) type process with natural zeolite circulation. This process consists of ammonium ion removal by zeolites and subsequent biological regeneration of zeolites. Two types of raw wastewater with high strength ammonia nitrogen (300–400 mg/L) from a fertilizer industry and a tannery industry, separately, were prepared for laboratory scale experiments. After ammonia ion removal from the influent wastewater by zeolite in the anoxic reactor, nitrifying bacteria, either attached to the zeolite or suspended in solution, participated in the conversion of ammonia to nitrite and nitrate in the following oxic reactor. Zeolites saturated with ammonia nitrogen were continuously regenerated and circulated in the proposed process without the use of chemical regenerants such as NaCl. Experimental results showed an 88–92% removal of ammonia nitrogen and high settleability in the final clarifier for both examples of wastewater. The results support that the proposed biological reactors with zeolite powder circulation are very effective in treating high strength nitrogen bearing wastewater.

scholarly journals Energy consumption and performance of a rotating biological contactor treating high-strength wastewater

2021 ◽  
Author(s):  
Rakesh Desai
Keyword(s):  
Energy Consumption ◽  
Angular Velocity ◽  
Oxygen Demand ◽  
High Strength ◽  
Ammonia Nitrogen ◽  
Aeration Rate ◽  
Synthetic Wastewater ◽  
Rotating Biological Contactor ◽  
Unit Energy ◽  
Unit Energy Consumption

Clean water availability, energy costs and the environmental impact of energy usage are major concerns all over the world. At the same time, the Rotating Biological Contactor (RBC) has emerged as a low energy-consuming technology used in wastewater treatment which compares favorably with other treatment methods. RBC is a fixed-film bioreactor employing rotating discs to provide support medium for the microbial growth and to supply dissolved oxygen. RBCs, when applied in the treatment of high strength wastewater, demand some modifications such as the addition of aeration systems or change the flow configuration. Aeration systems certainly reduce the footprint but at the cost of energy consumption. Therefore, the optimization of energy consumption in a modified RBC is a very relevant research objective. This thesis is an investigation on energy optimization in a commercial scale RBC modified with an aeration system and treating high strength synthetic wastewater. The coarse bubble diffuser was replaced by fine bubble air diffusers. To study energy consumption a mono-block main drive system and the central compressed air supply were replaced by a three phase motor with variable frequency drive and an aeration blower respectively. Removal performance and unit energy consumption were studied at various combinations of rotating speed (2.5-5 RPM) and rate of aeration (0-15 SCFM). Constant hydraulic (0.017 m³/m²-day), organic (86.1 gCOD/m²-day) and ammonia (3.444 gNH₃-N/m²-day) loadings were maintained throughout the study. The modified RBC was able to remove 34 to 96% COD and 21 to 68% ammonia depending on the aeration rate and angular velocity. The suspended growth section of the modified RBC contributed 47 to 85% and 38 to 87% of the total removal of COD and ammonia respectively. Conversion of ammonia-nitrogen to nitrate-nitrogen was observed very negligible at 0.26 to 1.59%. The angular velocity, 3.66 RPM and the rate of aeration 8.13 SCFM, were found to be the optimum parameters to achieve minimum unit energy consumption of 1.31 KWH/kg CODr. A mathematical model correlating energy consumption per unit oxygen demand with the rate of aeration and the angular velocity was developed.

Anaerobic Treatment of Coal Gasification Wastewater

1987 ◽  
Vol 19 (1-2) ◽  
pp. 229-236 ◽  
Author(s):  
Makram T. Suidan ◽  
Peter Fox ◽  
John T. Pfeffer
Keyword(s):  
Activated Carbon ◽  
Coal Gasification ◽  
Physical Adsorption ◽  
Oxygen Demand ◽  
Granular Activated Carbon ◽  
Anaerobic Treatment ◽  
Partial Replacement ◽  
Anaerobic Culture ◽  
Second Stage ◽  
Coal Gasification Wastewater

A sequence of unit processes consisting of a berl-saddle-packed anaerobic filter, an expanded-bed, granular activated carbon anaerobic reactor and an activated sludge nitrification system was employed for the treatment of synthetically prepared coal gasification wastewater. After acclimation, the coal gasification wastewater was fed to the treatment process train at three different chemical oxygen demand levels; these were 1,513. 3,027, and 7,567 mg/ℓ, respectively. No biological activity was observed in the first-stage filter, while excellent removal of organic matter was achieved in the second and third stages of the treatment systems. However, toxicity to the anaerobic culture in the second-stage reactor was observed during the second and third loading levels. This toxicity was overcome by employing a partial replacement schedule of the granular activated carbon medium in the reactor. This study represents an example of how biodegradation and physical adsorption may be successfully combined during the treatment of wastewaters containing toxic or inhibitory substances.

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