Groundwater denitrification with alternative carbon sources

1998 ◽  
Vol 38 (6) ◽  
pp. 237-243 ◽  
Author(s):  
A. Mohseni-Bandpi ◽  
D. J. Elliott
Keyword(s):  
Acetic Acid ◽  
Carbon Source ◽  
Nitrate Nitrogen ◽  
Nitrogen Concentration ◽  
Nitrate Removal ◽  
Carbon Sources ◽  
Pilot Scale ◽  
Rotating Biological Contactor ◽  
Nitrogen Ratio ◽  
Biological Nitrate Removal

A pilot scale rotating biological contactor (RBC) was used to investigate the removal of nitrate-nitrogen from groundwater using three different carbon sources, i.e., methanol, ethanol and acetic acid. Optimum carbon sources to influent nitrate-nitrogen ratio were established by varying the influent concentration of carbon sources. The optimum ratio of methanol, ethanol and acetic acid to nitrate-nitrogen ratios were found to be 2.9, 2.35 and 4.3 respectively. The nitrate-nitrogen removal efficiency averaged 93, 91 and 98 for methanol, ethanol and acetic acid respectively at a loading rate of 76 mg/m2.h. The results of this study show that the acetic acid is the most efficient carbon source for removal of nitrate-nitrogen. Effluent nitrite-nitrogen concentration was minimum for acetic acid as compared with ethanol and methanol. The effluent contained minimum suspended solids and turbidity for methanol as a carbon source. The results of this study indicate that biological nitrate removal using a RBC is a reliable and stable system under all the three carbon sources. The denitrified water in all cases requires some post treatment to oxidise the residual carbon source and remove biomass before distribution.

Denitrification of groundwater using acetic acid as a carbon source

1999 ◽  
Vol 40 (2) ◽  
pp. 53-59 ◽  
Author(s):  
A. Mohseni-Bandpi ◽  
D. J. Elliott ◽  
A. Momeny-Mazdeh
Keyword(s):  
Acetic Acid ◽  
Carbon Source ◽  
Nitrate Nitrogen ◽  
Removal Rate ◽  
Bacterial Species ◽  
Nitrate Removal ◽  
Pilot Scale ◽  
Operating Conditions ◽  
Acid Loading ◽  
Species Being

A pilot scale rotating biological contactor was used to investigate the ability to remove nitrate from groundwater using acetic acid as a carbon source under various operating conditions. The reactor achieved a nitrate removal efficiency of 99 to 83 percent at loading rates of 76 and 490 mg/m2.hr respectively with a flow rate of 2.5 l/min at 20±2°C. The nitrate removal rate was found to be dependent on the influent acetic acid loading rate. The optimum acetic acid to nitrate-nitrogen (A/N) ratio was found to be 4.3:1. Under optimum conditions the effluent nitrate, nitrite-nitrogen and residual acetic acid concentrations were 0.43, 0.03 and 4.4 mg/l. The process generally produced low nitrite intermediate production for up to 100 mg/l influent nitrate-nitrogen. The results of this study show that an anoxic RBC using acetic acid as a carbon source is a convenient and reliable process for the removal of nitrate from water supply. Pseudomonas were found to be the dominant bacterial species with species being Ps. stutzeri and Ps. fluorescence.

Nitrate removal using Brevundimonas diminuta MTCC 8486 from ground water

2009 ◽  
Vol 60 (2) ◽  
pp. 517-524 ◽  
Author(s):  
S. Kavitha ◽  
R. Selvakumar ◽  
M. Sathishkumar ◽  
K. Swaminathan ◽  
P. Lakshmanaperumalsamy ◽  
...  
Keyword(s):  
Carbon Source ◽  
Ground Water ◽  
Nitrate Removal ◽  
Carbon Sources ◽  
Treatment Plant ◽  
Growth Conditions ◽  
Pilot Scale ◽  
Biological Removal ◽  
Treatment Processes ◽  
Brevundimonas Diminuta

Brevundimonas diminuta MTCC 8486, isolated from marine soil of coastal area of Trivandrum, Kerala, was used for biological removal of nitrate from ground water collected from Kar village of Pali district, Rajasthan. The organism was found to be resistance for nitrate up to 10,000 mg L−1. The optimum growth conditions for biological removal of nitrate were established in batch culture. The effect of carbon sources on nitrate removal was investigated using mineral salt medium (MSM) containing 500 mg L−1 of nitrate to select the most effective carbon source. Among glucose and starch as carbon source, glucose at 1% concentration increased the growth (182±8.24 × 104 CFU mL−1) and induced maximum nitrate reduction (86.4%) at 72 h. The ground water collected from Kar village, Pali district of Rajasthan containing 460±5.92 mg L−1 of nitrate was subjected to three different treatment processes in pilot scale (T1 to T3). Higher removal of nitrate was observed in T2 process (88%) supplemented with 1% glucose. The system was scaled up to 10 L pilot scale treatment plant. At 72 h the nitrate removal was observed to be 95% in pilot scale plant. The residual nitrate level (23±0.41 mg L−1) in pilot scale treatment process was found to be below the permissible limit of WHO.

Comparison of denitrification performances using PLA/starch with different mass ratios as carbon source

2015 ◽  
Vol 71 (7) ◽  
pp. 1019-1025 ◽  
Author(s):  
Chuanfu Wu ◽  
Danqi Tang ◽  
Qunhui Wang ◽  
Juan Wang ◽  
Jianguo Liu ◽  
...  
Keyword(s):  
Carbon Source ◽  
Groundwater Remediation ◽  
Nitrate Concentration ◽  
Starch Content ◽  
Nitrate Removal ◽  
Carbon Sources ◽  
National Standard ◽  
Biofilm Carrier ◽  
Carbon Release ◽  
Biological Nitrate Removal

A suitable carbon source is significant for biological nitrate removal from groundwater. In this study, slow-release carbon sources containing polylactic acid (PLA) and starch at 8:2, 7:3, 6:4, 5:5, 4:6, and 3:7 ratios were prepared using a blending and fusing technique. The PLA/starch blend was then used as a solid carbon source for biological nitrate removal. The carbon release rate of PLA/starch was found to increase with increased starch content in leaching experiments. PLA/starch at 5:5 mass ratio was found to have the highest denitrification performance and organic carbon consumption efficiency in semi-continuous denitrification experiments, and was also revealed to support complete denitrification at 50 mg-N/L influent nitrate concentration in continuous experiments. The effluent nitrate concentration was <2 mg NO3–-N/L, which met the national standard (GB 14848-93) for groundwater. Scanning electron microscopy results further showed that the surface roughness of PLA/starch increased with prolonged experimental time, which may be conducive to microorganism attachment. Therefore, PLA/starch was a suitable carbon source and biofilm carrier for groundwater remediation.

scholarly journals Surveying Denitrification Efficacy in Up-Flow Packed Bed Bioreactor Operated under Heterotrophic Condition Using Autotrophic Bacteria

2019 ◽  
Author(s):  
Ali Asghar Neshat ◽  
Abdomajid Gholizadeh ◽  
Babak Jahed ◽  
Pouria Nikvand
Keyword(s):  
Acetic Acid ◽  
Carbon Source ◽  
High Efficiency ◽  
Nitrate Removal ◽  
Packed Bed ◽  
Critical Issue ◽  
Pilot Scale ◽  
Aqueous Environment ◽  
Packed Bed Bioreactor ◽  
Autotrophic Bacteria

Introduction: The biological denitrification process is an interesting cost-effective technique to remove nitrate from water supplies. Acetic acid can be used as a carbon source in this process, but its consumption rate is a critical issue and, in some cases, it is quite different from stoichiometric constants. The current study aimed to investigate the nitrate removal in an up-flow packed bed bioreactor. Furthermore, various parameters affecting this process were investigated and optimized. In this study, the autotrophic bacteria were used for the heterotrophic process. Materials and Methods: Initially, the autotrophic bacteria were cultured and used for the following heterotrophic conditions in distinct reactors. A pilot-scale anoxic up flow bioreactor packed was constructed using the polyethylene media and applied to remove nitrate from the aqueous environment. Consequently, the effects of hydraulic retention times (HRT) and different acetic acid concentrations as carbon source were evaluated. During the study, the amounts of alkalinity, pH, temperature, and nitrate were checked. Results: The designed bioreactor removed an average of over 88% of nitrate, while the acetic acid consumption was 2 mg/mg NO3-N, which was lower than the stoichiometric constant for heterotrophic process. Moreover, in the three studied HRTs (1.5, 3, and 5 h), the Alkalinity increased from 14.2 to 19.8 %. Conclusion: The results of this study showed high efficiency in nitrate removal via heterotrophic denitrification using acetic acid as carbon source for autotrophic bacteria.

Nitrate removal from groundwater using an anoxic-aerobic rotating biological contactor

1996 ◽  
Vol 34 (1-2) ◽  
pp. 323-330 ◽  
Author(s):  
A. Mohseni-Bandpi ◽  
D. J. Elliott
Keyword(s):  
Organic Carbon ◽  
Nitrate Nitrogen ◽  
Nitrate Removal ◽  
Carbon Sources ◽  
Optimum Conditions ◽  
Rotating Biological Contactor ◽  
Nitrite Nitrogen ◽  
In Series ◽  
Rotating Biological Contactors ◽  
Final Effluent

The removal of nitrate-nitrogen from groundwater was investigated using two rotating biological contactors (RBC) in series. The first pilot plant RBC reactor was operated under anoxic condition to remove nitrate-nitrogen. A fraction of effluent of the anoxic RBC was fed to a bench scale aerobic RBC to study the degradation of residual organic carbon and oxidation of nitrite-nitrogen. The first reactor achieved a nitrate removal efficiency of 90 percent for a loading rate of 76 mg/m2.h. The corresponding effluent nitrate, nitrite and residual carbon sources concentrations amounted to 3.3, 0.34 and 3.9 mg/l, respectively. The optimum ethanol to nitrate-nitrogen (E/N) ratio was found to be 2.35. No residual ethanol and nitrite-nitrogen were observed in the final effluent under optimum conditions. Dissolved oxygen in the final effluent was found to be greater than 7 mg/l. The results of the study suggest that using a continuous anoxic-aerobic RBC is a convenient and reliable process for removal of nitrate, residual organic carbon and nitrite.

Denitrification with isopropanol as a carbon source in a biofilm system

1994 ◽  
Vol 30 (11) ◽  
pp. 69-78 ◽  
Author(s):  
Yongwoo Hwang ◽  
Hiroshi Sakuma ◽  
Toshihiro Tanaka
Keyword(s):  
Carbon Source ◽  
Nitrate Removal ◽  
Growth Yield ◽  
Pilot Scale ◽  
Denitrification Rate ◽  
Hydrogen Donor ◽  
Microbial Oxidation ◽  
Biological Denitrification ◽  
Batch Tests

Several batch tests and pilot-scale investigations on biological denitrification with isopropanol were performed. Isopropanol was converted to acetone by microbial oxidation during denitrification. Isopropanol itself little contributed to denitrification in practice while the converted acetone played a role of a main hydrogen donor. A larger quantity of nitrite intermediate was formed by using methanol compared to the case of isopropanol. The measured requirement of isopropanol was 2.0 mg mg−1 NO3-N, and was 2/3 of methanol. The oxygen equivalent of isopropanol for nitrate removal was almost the same as that of methanol. The denitrifier net growth yield for isopropanol was greater than for methanol. In order to maximize the denitrification rate, it is essential to convert isopropanol to acetone rapidly by accurate dosing for nitrogen load because the denitrification rate was accelerated by using acetone only. Excessive dose of isopropanol can cause a decrease in the denitrification rate as well as an increase of BOD in the effluent.

Experimental effect of medium ratio on removal efficiency of nitrate nitrogen in groundwater by zero-valent iron, activated carbon and zeolite

2019 ◽  
Vol 19 (6) ◽  
pp. 1636-1642
Author(s):  
Sizhi Cao ◽  
Peigui Liu ◽  
Mingchao Liu ◽  
Gang Wang ◽  
Zaili Li ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Nitrate Nitrogen ◽  
Nitrogen Concentration ◽  
Nitrate Removal ◽  
Ammonia Nitrogen ◽  
Coarse Sand ◽  
Zero Valent Iron ◽  
Nitrite Nitrogen ◽  
Rich Solution ◽  
Set Up

Abstract In this study, column experiments in the laboratory were set up to examine how the concentrations of nitrate nitrogen, nitrite nitrogen, and ammonia nitrogen changed when a nitrate-rich solution was passed through a medium comprising zero-valent iron, activated carbon, zeolite, and coarse sand. We varied the proportions of the components of the medium to determine how it influenced the nitrate removal and nitrogen fractions. Three different scenarios were used, with: (1) iron, activated carbon, and coarse sand at a ratio of 3:1:6; (2) iron, activated carbon, and zeolite at a ratio of 3:1:6; and (3) iron, activated carbon, and zeolite at a ratio of 3:3:4. The nitrate nitrogen concentration decreased from 25 mg/L to 2 mg/L in the first scenario. Removal was better when zeolite was added to the medium as most of the nitrate nitrogen broke down to ammonia nitrogen, with nitrite nitrogen as an intermediate product. The results of the tests showed that nitrate removal was best when the medium was iron, activated carbon, and zeolite, mixed at a ratio of 3:1:6. This study provides a scientific reference for in situ remediation of nitrate pollution in groundwater.

Full-Scale Application of Nitrogen Removal with Methanol as Carbon Source

1992 ◽  
Vol 26 (5-6) ◽  
pp. 1077-1086 ◽  
Author(s):  
U. Nyberg ◽  
H. Aspegren ◽  
B. Andersson ◽  
J. la C. Jansen ◽  
I.S. Villadsen
Keyword(s):  
Carbon Source ◽  
Nitrogen Removal ◽  
Nitrate Removal ◽  
Sewage Treatment ◽  
Carbon Sources ◽  
Treatment Plant ◽  
Cost Effective ◽  
High Level ◽  
Plant Configuration ◽  
Composite Samples

In Sweden many advanced sewage treatment plants for BOD and phosphorus removal have to be extended with nitrogen removal. Due to existing plant configuration and wastewater composition, denitrification with supply of an external carbon source can be a cost-effective solution in many cases. At the Klagshamn wastewater treatment plant in Malmo investigations for extensive nitrogen removal have been made in a single-sludge system with pre-precipitation and post-denitrification where methanol was added for denitrification. Results from the tests showed that a high level of nitrogen removal can be reached, and that the process was stable and easy to operate. The process application gave less supplementary cost for an extended nitrogen removal than for upgrading the plant with larger basin volumes. In order to examine the purification performance caused by the addition of methanol, the starting period was followed extensively with online nitrate sensors and daily composite samples. The development of the denitrif ication capacity of the sludge with methanol and acetate as carbon sources was followed and microbiological changes were examined microscopically. Complete denitrification was obtained after approximately one month at 10°C. The denitrification capacity of the sludge with methanol reached that of acetate after about the same time. The microscopic examination revealed a growing population of budding and/or appendaged bacteria, presumably Hyphomicrobium spp, reaching a stable maximum at the time when optimal nitrate removal occurred.

Biological nitrate removal using waste-derived extracts as sole carbon source

2014 ◽  
Vol 14 (3) ◽  
pp. 276
Author(s):  
Subhankar Basu ◽  
Sakshi Verma ◽  
Ravi Karan Singh ◽  
Vidya S. Batra ◽  
Malini Balakrishnan
Keyword(s):  
Carbon Source ◽  
Sole Carbon Source ◽  
Nitrate Removal ◽  
Biological Nitrate Removal

Comparative Analysis of Nitrate Removal in Sub-Surface Flow Constructed Wetlands by Different External Carbon Sources

2014 ◽  
Vol 1073-1076 ◽  
pp. 779-783
Author(s):  
Patience Awhavbera ◽  
Lian Fang Zhao
Keyword(s):  
Carbon Source ◽  
Wheat Straw ◽  
Constructed Wetlands ◽  
Nitrate Removal ◽  
Waste Product ◽  
Carbon Sources ◽  
Surface Flow ◽  
Synthetic Wastewater ◽  
External Carbon Source ◽  
N Removal

External carbon sources provide additional nutrients that improve the efficiency of nitrate removal in constructed wetlands. Typha angustifolia L. were planted in four vertical subsurface-flow constructed wetlands. Different external carbon sources were fed into the columns, to investigate and compare their treatment of nitrate in synthetic wastewater, with initial influent C/N ratio of 1:1. Wetland A (WA) with 50g wheat straw as external carbon source, wetland B (WB) with 50g woodchips, wetland C (WC) with additional 10mg/L glucose and wetland D (WD) without external carbon source to serve as the control, were used in the lab-scale experimental study. WA, WB, WC and WD within a period of 24 days, cumulatively removed 109.38mg/L, 93.75mg/L, 85.14mg/L, and 64.01mg/L nitrate, respectively, from the influent. The nitrate-nitrogen (NO3–N) removal efficiency as aided by the external carbon sources was in the order: wheat straw > woodchips > glucose > control. Wheat straw treated 93% NO3–N, woodchips 78%, glucose 72% and the control 53%. The results indicate that WA, WB and WC outperformed the control system, due to the additional carbon sources. In general, the wheat straw had a better performance than wood chips and glucose. Thus, wheat straw as low cost biological waste product is recommended for the treatment of nitrate in wetlands.

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