Scrap Iron Filings assisted nitrate and phosphate removal in low C/N waters using mixed microbial culture

Highlights

• Microbes enhance denitrification under varying DO concentrations and SIF dosages.

• Abiotic nitrate reduction rates are proportional to SIF age and dosage.

• Over 80% of the simultaneously loaded NO₃⁻-N and PO₄³⁻ is removed biologically.

Abstract

This study focuses on identifying the factors under which mixed microbial seeds assist bio-chemical denitrification when Scrap Iron Filings (SIF) are used as electron donors and adsorbents in low C/N ratio waters. Batch studies were conducted in abiotic and biotic reactors containing fresh and aged SIF under different dissolved oxygen concentrations with NO₃⁻-N and/or PO₄^3- influent(s) and their nitrate/phosphate removal and by-product formations were studied. Batch reactors were seeded with a homogenized mixed microbial inoculum procured from natural sludges which were enriched over 6 months under denitrifying conditions in the presence of SIF. Results indicated that when influent containing 40 mg/L of NO₃⁻-N was treated with 5 g SIF, 79.9% nitrate reduction was observed in 8 days abiotically and 100% removal was accomplished in 20 days when the reactor was seeded. Both abiotic and seeded reactors removed more than 92% PO₄³⁻ under high DO conditions in 12 days. Abiotic and biochemical removal of NO₃⁻-N and abiotic removal of PO₄³⁻ were higher under independent NO₃⁻-N/PO₄³⁻ loading, while 99% PO₄^3- was removed biochemically under combined NO₃⁻-N and PO₄³⁻ loading. This study furthers the understandings of nitrate and phosphate removal in Zero Valent Iron (ZVI) assisted mixed microbial systems to encourage the application of SIF-supported bio-chemical processes in the simultaneous removals of these pollutants.

Graphical abstract

Keywords

Scrap iron filing / Nitrate removal / Phosphate removal / Mixed culture denitrification / Zero valent iron

References

[1] Aragno M, Schlegel H G (1981). The prokaryotes. In: Starr M P, Stolp H, Trüper H G, Balows A, Schlegel H G (eds). The Prokaryotes: A Handbook on Habitats, Isolation, and Identification of Bacteria. Berlin, Heidelberg: Springer Berlin Heidelberg, 865–893

[2] Bardos P, Bone B, Elliott D, Hartog N, Henstock J, Nathanail P(2011). A risk/benefit approach to the application of iron nanoparticles for the remediation of contaminated sites in the environment. London: Department for Food the Environment and Rural Affairs- Defra,1–111

[3] Brettar I, Christen R, Hofle M G (2002). Rheinheimera baltica gen. nov., sp. nov., a blue-coloured bacterium isolated from the central Baltic Sea. International Journal of Systematic and Evolutionary Microbiology, 52(Pt 5): 1851–1857

[4] Cheng I F, Muftikian R, Fernando Q, Korte N (1997). Reduction of nitrate to ammonia by zero-valent iron. Chemosphere, 35(11): 2689–2695

[5] Chinese N E P A (2002). Water and wastewater monitoring methods 4th ed. Beijing: Chinese Environmental Science Publishing House

[6] Du Q, Zhang S, Pan B, Lv L, Zhang W, Zhang Q (2014). Effect of spatial distribution and aging of ZVI on the reactivity of resin–ZVI composites for arsenite removal. Journal of Materials Science, 49(20): 7073–7079

[7] Fu F, Dionysiou D D, Liu H (2014). The use of zero-valent iron for groundwater remediation and wastewater treatment: A review. Journal of Hazardous Materials, 267: 194–205

[8] Giacomelli C, Spinelli A (2004). A potentiodynamic and SEM study of the behaviour of iron in pH 8.9–11.0 phosphate solutions. Anti-Corrosion Methods and Materials, 51(3): 189–199

[9] Guo C H, Stabnikov V, Ivanov V (2010). The removal of nitrogen and phosphorus from reject water of municipal wastewater treatment plant using ferric and nitrate bioreductions. Bioresource Technology, 101(11): 3992–3999

[10] Hao Z W, Xu X H, Wang D H(2005). Reductive denitrification of nitrate by scrap iron filings. Journal of Zhejiang University. Science. B, 6(3): 182–186

[11] Hu R, Gwenzi W, Sipowo-Tala V R, Noubactep C(2019). Water treatment using metallic iron: A tutorial review. Processes, 7(9): 622

[12] Ivanov V, Kuang S, Stabnikov V, Guo C (2009). The removal of phosphorus from reject water in a municipal wastewater treatment plant using iron ore. Journal of Chemical Technology and Biotechnology (Oxford, Oxfordshire), 84(1): 78–82

[13] Jeong J Y, Song Y H, Kim J H, Park J Y (2013). Simultaneous removal of nitrate, phosphate, and fluoride using a ZVI-packed bed electrolytic cell. Desalination and Water Treatment, 52(4–6): 737–743

[14] Ji B, Wang H, Yang K (2014). Tolerance of an aerobic denitrifier (Pseudomonas stutzeri) to high O₂ concentrations. Biotechnology Letters, 36(4): 719–722

[15] Kielemoes J, De Boever P, Verstraete W (2000). Influence of denitrification on the corrosion of iron and stainless steel powder. Environmental Science & Technology, 34(4): 663–671

[16] Kim B C, Kim S, Shin T, Kim H, Sang B I (2013). Comparison of the bacterial communities in anaerobic, anoxic, and oxic chambers of a pilot A²O process using pyrosequencing analysis. Current Microbiology, 66(6): 555–565

[17] Lavania A, Bose P (2006). Effect of metallic iron concentration on end-product distribution during metallic iron-assisted autotrophic denitrification. Journal of Environmental Engineering Bioresource technology, 132(9): 994–1000

[18] Lee K C Y, Dunfield P F, Stott M B (2014). The Phylum Armatimonadetes. In: Rosenberg E, DeLong E F, Lory S, Stackebrandt E, Thompson F (eds). The Prokaryotes: Other Major Lineages of Bacteria and The Archaea. Berlin, Heidelberg: Springer Berlin Heidelberg, 447–458

[19] Lee S, Yun Y, Kim D G (2017). Nitrate reduction by micro-scale zero-valent iron particles under oxic condition. KSCE Journal of Civil Engineering, 21(6): 2119–2127

[20] Lefevre E, Bossa N, Wiesner M R, Gunsch C K (2016). A review of the environmental implications of in situ remediation by nanoscale zero valent iron (nZVI): Behavior, transport and impacts on microbial communities. Science of the Total Environment, 565: 889–901

[21] Liessens J, Vanbrabant J, De Vos P, Kersters K, Verstraete W (1992). Mixed culture hydrogenotrophic nitrate reduction in drinking water. Microbial Ecology, 24(3): 271–290

[22] Liu F, Zuo J, Chi T, Wang P, Yang B (2015). Removing phosphorus from aqueous solutions by using iron-modified corn straw biochar. Frontiers of Environmental Science & Engineering, 9(6): 1066–1075

[23] Liu Y, Li S, Chen Z, Megharaj M, Naidu R (2014). Influence of zero-valent iron nanoparticles on nitrate removal by Paracoccus sp. Chemosphere, 108: 426–432

[24] Mao Y, Xia Y, Zhang T (2013). Characterization of Thauera-dominated hydrogen-oxidizing autotrophic denitrifying microbial communities by using high-throughput sequencing. Bioresource Technology, 128: 703–710

[25] Metcalf Eddy Inc., Tchobanoglous G., Stensel H., Tsuchihashi R., Burton F (2014). Wastewater Engineering: Treatment and Resource Recovery-Vol. 2. BostanA: McGraw-Hill

[26] McCarty P L (1975). Stoichiometry of biological reactions. Progress in Water Technology, 7(1): 157–172

[27] Patureau D, Helloin E, Rustrian E, Bouchez T, Delgenes J P, Moletta R (2001). Combined phosphate and nitrogen removal in a sequencing batch reactor using the aerobic denitrifier, Microvirgula aerodenitrificans. Water Research, 35(1): 189–197

[28] Sleiman N, Deluchat V, Wazne M, Mallet M, Courtin-Nomade A, Kazpard V, Baudu M (2017). Phosphate removal from aqueous solutions using zero valent iron (ZVI): Influence of solution composition and ZVI aging. Colloids and Surfaces. A, Physicochemical and Engineering Aspects, 514: 1–10

[29] Stefaniuk M, Oleszczuk P, Ok Y S(2016). Review on nano zerovalent iron (nZVI): From synthesis to environmental applications. Chemical Engineering Journal, 287: 618–632

[30] Tilche A, Rambaldi A, Gemelli S, Bortone G (1992). Nitrification, denitrification and biological phosphate removal in sequencing batch reactors treating piggery wastewater. Water Science and Technology, 26(5–6): 977–985

[31] Till B A, Weathers L J, Alvarez P J J (1998). Fe⁰-supported autotrophic denitrification. Environmental Science & Technology, 32(5): 634–639

[32] Vavilin V A, Rytov S V (2015). Nitrate denitrification with nitrite or nitrous oxide as intermediate products: Stoichiometry, kinetics and dynamics of stable isotope signatures. Chemosphere, 134: 417–426

[33] Xu D, Li Y, Yin L, Ji Y, Niu J, Yu Y (2018). Electrochemical removal of nitrate in industrial wastewater. Frontiers of Environmental Science & Engineering, 12(1): 9

[34] Yang G C, Lee H L (2005). Chemical reduction of nitrate by nanosized iron: Kinetics and pathways. Water Research, 39(5): 884–894

[35] Zala S L, Ayyer J, Desai A J (2004). Nitrate removal from the effluent of a fertilizer industry using a bioreactor packed with immobilized cells of Pseudomonas stutzeri and Comamonas testosteroni. World Journal of Microbiology & Biotechnology, 20(7): 661–665

Acknowledgements

We are grateful for the project grants supported by the Major Science and Technology Programs for Water Pollution Control and Management of China (Nos. 2012ZX07205-001 and 2017ZX7103-007).

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