Document Type : Full article
1 chemical and Petroleum engineering department, Semnan University
2 Department of Petroleum and Chemical Engineering, Islamic Azad University, Science and Research Branch, Tehran, Iran
Many communities in the world use groundwater as a source of potable water. The high nitrate concentration is a serious problem in groundwater usage. This study utilizes a biological denitrification method to investigate a moving bed biofilm reactor (MBBR) for the case of Tehran's groundwater. One pilot-scale MBBR with a 3 liter volume was designed and used in this research. The denitrification reactor operates under anoxic conditions. Methanol was used as a carbon source in the reactor throughout the study, and fifty percent of the reactor volume was occupied with KMT packing (k1). To determine the optimum nitrate loading rate, the concentration of nitrate changed from 100 to 400 mg N/l. It was concluded that heterotrophic denitrifying bacteria converted nitrate to nitrogen. According to obtained results, the removal efficiency and optimum loading rate were estimated during the experiments in different concentrations and different HRTs for this type of reactor. Sodium nitrate was in the feed source in the anoxic reactor. The maximum removal rate of nitrate was measured to be 2.8 g of NO3-N m-2 carrier d-1. Therefore, it was shown that the optimum loading rate of nitrate and the optimum COD/N were equal to 3.2 g of NO3-N m-2 carrier d-1 and 6 g of COD/g N respectively.
- Xing, W., Li, D., Li, J., Hu, Q. and Deng, S., “Nitrate removal and microbial analysis by combined micro-electrolysis and autotrophic denitrification”, Bioresource Technology, 211, 240 (2016). (https://doi.org/10.1016/jbiortec.2016.03.044).
- Su, J. -F., Shi, J. -X., Huang, T. -L., Ma, F., Lu, J. -S. and Yang, S. -F., “Effect of nitrate concentration, pH, and hydraulic retention time on autotrophic denitrification efficiency with Fe(II) and Mn(II) as electron donors”, Water Science and Technology, A Journal of the International Association on Water Pollution Research, 74 (5), 1185 (2016). (https://doi.org/10.2166/wst.2016.231).
- Leyva-Díaz, J. C., González-Martínez, A., González-López, J., Muñío, M. M., and Poyatos, J. M., “Kinetic modeling and microbiological study of two-step nitrification in a membrane bioreactor and hybrid moving bed biofilm reactor-membrane bioreactor for wastewater treatment”, Chemical Engineering Journal, 259, 692 (2015). (https://doi.org/10.1016/j.cej.2014.07.136).
- Huang, T. L., Zhou, S. L., Zhang, H. H., Bai, S. Y., He, X. X. and Yang, X., “Nitrogen removal characteristics of a newly isolated indigenous aerobic denitrifier fromoligotrophic drinking water reservoir, Zoogloea N299”, International Journal of Molecular Sciences, 16 (5), 10038 (2015). (https://doi.org/10.3390/ijms160510038).
- Ødegaard, H., Rusten, B. and Westrum, T., “A new moving bed biofilm reactor-applications and results”, Water Science and Technology, 29 (10), 157 (1994). (https://doi.org/10.2166/wst.1994.0757).
- Angar, Y., Kebbouche-Gana, S., Djelali, N. E. and Khemili-Talbi, S., “Novel approach for the ammonium removal by simultaneous heterotrophic nitrification and denitrification using a novel bacterial species co-culture”, World Journal of Microbiology and Biotechnology, 32 (3), 1 (2016). (https://doi.org/1007/s11274-015-2007-y).
- Zhang, H., Wang, H., Yang, K., Sun, Y., Tian, J. and Lv, B., “Nitrate removal by a novel autotrophic denitrifier (Microbacterium) using Fe(II) as electron donor”, Annals of Microbiology, 65 (2), 1 (2015). (https://doi.org/10.1007/s13213-014-0952-6).
- Jessen, S., Postma, D., Thorling, L., Müller, S., Leskelä, J. and Engesgaard, P., “Decadal variations in groundwater quality: A legacy from Nitrate leaching and denitrification by pyrite in a sandy aquifer”, Water Resour., 27, 2027 (2017). (https://doi.org/10.1002/2016wr018995).
- Gao, H., Liu, M., Griffin, J. S., Xu, L., Xiang, D., Scherson, Y. D. and Wells, G. F., “Complete nutrient removal coupled to nitrous oxide production as a bioenergy source by denitrifying polyphosphate-accumulating organisms”, Sci. Technol., 51 (8), 4531(2017). (https://doi.org/10.1021/acs.est.6b04896)
- Chen, X., Yuan, Z. and Ni, B. J., “Nitrite accumulation inside sludge flocs significantly influencing nitrous oxide production by ammoniumoxidizing bacteria”, Water Res., 143, 99 (2018). (https://doi.org/10.1016/j.watres.2018.06.025).
- Hai, R., He, Y., Wang, X. and Li, Y., “Simultaneous removal of nitrogen and phosphorus from swine wastewater in a sequencing batch biofilm reactor”, J. Chem. Eng., 23, 303 (2015). (https://doi.org/10.1016/j.cjche.2014.09.036).
- Chen, J., Zheng, J., Li, Y., Hao, H. H. and Chen, J. M., “Characteristics of a novel thermophilic heterotrophic bacterium, Anoxybacillus contaminans HA, for nitrification–aerobic denitrification”, Applied Microbiology & Biotechnology, 99 (24), 10695 (2015). (https://doi.org/10.1007/s00253-015-6870-0).
- Kamble, S. J., Chakravarthy, Y., Singh, A., Chubilleau, C., Starkl, M. and Bawa, I., “A soil biotechnology system for wastewater treatment: Technical, hygiene, environmental LCA and economic aspects”, Sci. Pollut., 24, 13315 (2017). (https://doi.org/10.1007/s11356-017-8819-6).
- Jones, R. R., Weyer, P. J., DellaValle, C. T., Inoue-Choi, M., Anderson, K. E., Cantor, K. P. and Ward, M. H., “Nitrate from drinking water and diet and bladder cancer among postmenopausal women in Iowa”, Health Perspect., 124, 1751 (2016). (https://doi.org/10.1289-ehp191).
- Jasechko, S., Perrone, D., Befus, K. M., Cardenas, M. B., Ferguson, G., Gleeson, T. and Kirchner, J. W., “Global aquifers dominated by fossil groundwaters but wells vulnerable to modern contamination”, Geosci., 10, 425 (2017). (https://doi.org/10.1038/ngeo2943).
- Abzazou, T., Araujo, R. M., Auset, M. and Salvadó, H., “Tracking and quantification of nitrifying bacteria in biofilm and mixed liquor of a partial nitrification MBBR pilot plant using fluorescence in situ hybridization”, Total Environ., 541, 1115 (2016). (https://doi.org/10.1016/j.scitotenv.2015.10.007).
- Rongoei, P. J. K. and Outa, N. O., Standard methods for the examination of water and wastewater, 20th, American Public Health Association, Washington DC, USA, (1999).