Nutrient management via struvite precipitation and recovery from various agroindustrial wastewaters: Process feasibility and struvite quality

Raffaele Taddeo, Mari Honkanen, Kari Kolppo, Raghida Lepistö

    Research output: Contribution to journalArticleScientificpeer-review

    27 Citations (Scopus)

    Abstract

    Improving environmental protection and finding sustainable and renewable resources of nutrients are core issues in circular bioeconomy. Thus, this study evaluated the efficiency of recovering struvite, MgNH4PO4·6H2O, from different agro-industrial wastewaters (four highly loaded reject waters of anaerobically co-digested agro-industrial waste and a raw swine slurry) and assessed the quality of recovered struvite crystals and their reusability as fertilizer. The efficiency of crystallization (Ec 40–80%) and amount of struvite in the precipitate (Pp 55–94%) highly varied due to the characteristics of influent wastewaters, particularly to the content of competing elements, such as alkaline and heavy metals and total solids (TS). In particular, Ec (94, 75, 61%) and Pp (76, 66, 48%) decreased at increasing TS (0.57, 0.73, 0.99%), demonstrating the hindering effect of solid content on struvite recovery and quality. According to X-ray diffraction analysis, the structure of all isolated samples corresponded to crystalline, orthorhombic struvite, which exhibited high purity (32–48 g/kgd N, 114–132 g/kgd P, and 99–116 g/kgd Mg) containing only a few foreign elements, whose amount depended on the characteristics of the influent wastewater. All struvite contained other plant macronutrients (K, Ca) and many micronutrients (Fe, Na, Cu, Mn, Co, Zn) that further enhance its agronomic value. Therefore, this study showed that struvite can be successfully recovered from a wide range of highly loaded agroindustrial wastewaters, and that the quality of the recovered struvite could be suitable for reuse in agriculture.

    Original languageEnglish
    Pages (from-to)433-439
    Number of pages7
    JournalJournal of Environmental Management
    Volume212
    DOIs
    Publication statusPublished - 15 Apr 2018
    Publication typeA1 Journal article-refereed

    Keywords

    • Crystalline purity
    • Heavy metals
    • Nutrient recycling
    • Solid content
    • Sustainable fertilizer

    Publication forum classification

    • Publication forum level 1

    ASJC Scopus subject areas

    • Environmental Engineering
    • Waste Management and Disposal
    • Management, Monitoring, Policy and Law

    Fingerprint Dive into the research topics of 'Nutrient management via struvite precipitation and recovery from various agroindustrial wastewaters: Process feasibility and struvite quality'. Together they form a unique fingerprint.

    Cite this