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ARS Home » Pacific West Area » Maricopa, Arizona » U.S. Arid Land Agricultural Research Center » Water Management and Conservation Research » Research » Publications at this Location » Publication #380733
Research Project: The Use of Treated Municipal Waste Water as a Source of New Water for Irrigation

Location: Water Management and Conservation Research

Title: Low concentrations of Cu2+ in synthetic nutrient containing wastewater inhibit MgCO3-to-struvite transformation

Author
item BARCAUSKAITE, KAROLINA - Lithuanian Research Centre For Agriculture And Forestry
item DRAPANAUSKAITE, DONATA - Lithuanian Research Centre For Agriculture And Forestry
item SILVA, MANOJ - Lehigh University
item MURZIN, VADIM - University Of Wuppertal
item DOYENI, MODUPE - Lithuanian Research Centre For Agriculture And Forestry
item URBONAVICIUS, MARIUS - Lithuanian Energy Institute
item Williams, Clinton
item SUPRONIENE, SKAIDRE - Lithuanian Research Centre For Agriculture And Forestry
item BALTRUSAITIS, JONAS - Lehigh University

Submitted to: Environmental Science: Water Research & Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/28/2020
Publication Date: 12/29/2020
Citation: Barcauskaite, K., Drapanauskaite, D., Silva, M., Murzin, V., Doyeni, M., Urbonavicius, M., Williams, C.F., Suproniene, S., Baltrusaitis, J. 2020. Low concentrations of Cu2+ in synthetic nutrient containing wastewater inhibit MgCO3-to-struvite transformation. Environmental Science: Water Research & Technology. 7(3):521-534. https://doi.org/10.1039/D0EW01035A.
DOI: https://doi.org/10.1039/D0EW01035A

Interpretive Summary: Struvite synthesis can simultaneously remove both nitrogen and phosphorous from wastewater streams for use as a fertilizer. The precipitation of struvite from wastewater occurs in the presence of many other contaminants that have the potential to limit crystal formation and prevent nutrient removal. Zinc and copper are common ions present in wastewater that may affect the production of struvite. Results show that concentrations of Zn up to 100 mg/L have no adverse affects on struvite production but copper concentrations as low as 5 mg/L can prevent struvite precipitation. In addition to interfering with struvite formation copper was also shown to reduce soil microbial activity consistent with copper toxicity. These results will help provide recommendations for potential pretreatment for wastewater containing coper prior to struvite production.

Technical Abstract: Simultaneous major nutrient nitrogen (N) and phosphorous (P) recovery from wastewater is key in achieving food-energy-water sustainable development. In this work, we elucidate the reaction kinetics, crystalline structure and chemical composition of the resulting solid precipitate obtained from simulated N and P containing wastewater solution using widely abundant low solubility magnesite (MgCO3) particles in the presence of the common transition metal ions, such as zinc (Zn2+) or copper (Cu2+). We show that up to 100 ppm Zn2+ from the simulated wastewater can be incorporated into the struvite lattice as isolated distorted Zn2+ while even at very low concentrations of ~5 ppm Cu2+ ions almost completely inhibit struvite crystal formation. The resulting solid precipitate distinctly affects soil microbial biomass carbon and soil dehydrogenase enzyme activity. These results show a cautionary case where abundant natural mineral MgCO3 exhibits very different chemistry in Cu2+ containing simulated wastewater and does not readily adsorb or retain NH4+ and PO43- ions, unlike less sustainable but more water-soluble magnesium source, such as MgCl2, at the equivalent molar [Mg2+]:[NH4+]:[PO43-] ratio of [1.4:1:1].